The multiple faces of pain in motor neuron disease: a qualitative study to inform pain assessment and pain management

Abstract

Purpose: The aim was to explore personal experiences of pain in people with motor neuron disease.

Materials and methods: Sixteen participants were individually interviewed on one occasion concerning their experiences of presentation, consequences, and management of pain. Qualitative content analysis with researcher triangulation was used to synthesize and interpret data.

Results: Four themes emerged as the result of the analysis: (1) The multiple faces of pain, (2) The thin line between experience of pain and no pain, (3) The negative effects of pain on role functioning (4) Successful coping with pain requiring personal effort and competent engagement. The important findings were the experiences of unpredictability of pain breakthroughs, the efforts required to manage pain, consequences for activity and quality of life, and the suffering induced by diminishment and neglect of pain from both patients and staff.

Conclusions: Pain in motor neuron disease seems to have certain and multiple characteristics, which is why there is a need to develop and implement pain assessment methods adapted to this population. Such methods may help make pain more predictable, and increase the possibilities to provide effective and individually tailored pain treatment.

IMPLICATIONS FOR REHABILITATION

• Pain is a common, but often neglected, ailment in motor neuro disease, which deserves more attention from health care.

• Staff should provide information about the pain being possible to treat successfully with medication, by contrast to the possibility of curing the disease itself.

• Pain assessments should be implemented during the entire course of the disease, covering a time frame long enough to cover characteristic fluctuations of pain.

• Whenever possible, facilitate the performance of painful activities of daily living as much as possible to make room for engagement in other personally valued activities of importance for individual quality of life.

Keywords:

• Amyotrophic Lateral Sclerosis
• motor neuron disease
• pain assessment
• coping
• pain management
• qualitative content analysis

Introduction

Motor neuron diseases (MNDs) such as Amyotrophic Lateral Sclerosis (ALS) and primary lateral sclerosis (PLS) are degenerative, progressive diseases which primarily affect motor neurons [1]. Throughout the paper, MND is used when referring to the broader grouping of the diseases, whereas ALS and PLS when referring to either of the more specific diagnoses. The loss of motor neuron function can cause muscular weakness, muscular atrophy, spasticity, bulbar dysfunction, and respiratory impairment. The latter contributes to the short and progressive time course of ALS, with a survival of 3–5 years after the onset of symptoms [2,3]. For the MNDs, there is no curable therapy yet, which is why treatment mainly targets symptom control rather than control of disease progression [3].

Historically, there has been an emphasis on motor symptoms in MNDs [4]. However, persons with ALS also experience a series of non-motor symptoms, which have been acknowledged during the past decade in treatment and palliative care, e.g., cognitive impairment, anxiety and depression, sleep disorders, sensory abnormalities and pain [5,6]. Still, there is a need to improve characterization of non-motor symptoms, such as pain, to complement the understanding of the disease and the suffering it causes for those affected.

The reported prevalence of pain in ALS varies from 15% to 85% [7]. This large variability can be attributed to differences in definitions and measurements used to identify and quantify pain, and in study designs and settings [7]. The clinical manifestation of pain in ALS varies extensively, which has been interpreted as variation depending on whether the mechanisms behind pain represent primary mechanisms or secondary consequences of motor degeneration [7]. Pain can be acute or chronic, occurring in different stages of the disease [8–10]. There is no typical localization of pain related to ALS, and pain could be localized to the head, neck or lumbar region [11], proximally and distally in the upper and lower extremities, or widespread [7]. Reported pain intensity varies between studies from mild [8,10,12], to moderate [11], to severe [13], with indications of higher pain intensity in the last stage of the disease [14].

Stephen et al [12] found that pain intensity was not associated with pain interference in daily living, but this has been contradicted by others [8,10]. Further, pain in ALS is generally regarded to account for deterioration in quality of life [8,15], but studies show that this could be due to co-morbidity with depression [13], which calls for studies looking further into these associations. Worth heeding is also that perceptions of pain severity in persons with ALS vary between individuals, similar to other chronic pain conditions, which is why we assume that pain perceptions are associated with attention, emotion, expectations, and context [16].

Altogether, pain in ALS has gained increased attention in recent years, but there are still many facets to explore scientifically [7]. Further, there is an urgent need for improvements regarding clinical management. According to a US survey, physicians, nurses, physical and occupational therapists generally assess pain in patients with MND, but this is done more generally by use of open ended questions, and very few use standardized procedures including rating scales [12]. Guidelines for clinical pain assessment, including rating scales valid for the presentation of pain for this particular group of patients are called for [7].

To summarize, current knowledge regarding pain in MND stems from studies using a variety of pain definitions, measures, and study designs which have in common their origin in a positivistic paradigm. To the best of our knowledge, there are no naturalistic inquiries contributing with knowledge on how pain is experienced in an everyday life context by those afflicted. From scientific as well as clinical point of views, there is a need to develop pain assessment methods valid to this population to enable thorough and systematic characterizations of pain, and pain severity. To make this possible, we propose that personal experiences of pain need to be understood and synthesized in a scientific and credible way. Such data is currently missing, but would expand knowledge on the meaning behind quantitative results, and thereby inform the development of new pain assessment methods. In addition, such data would contribute to hypotheses about what constitute clinically relevant strategies for pain management. Therefore, the aim of this study was to explore personal experiences of pain in people with MND.

Materials and methods

Philosophical assumptions and research design

This study draws on a relativist ontology where multiple realities are accepted as valuable knowledge. Knowledge is seen as socially constructed, not independent of the knower but based on different value systems and experiences [17]. We postulate that it is essential to understand the phenomenon of interest, here pain and MND, from the perspectives of individuals having this particular experience.

The study had a qualitative, explorative design. Data were collected with personal, face-to-face interviews on one occasion per participant. Qualitative content analysis [18] was used to synthesize and interpret the data.

Setting and participants

The setting for the study was a university hospital in Sweden. The MND team includes a neurologist, a nurse, a medical social worker, a physiotherapist, an occupational therapist, a speech therapist and a dietician. Persons living in the region being diagnosed with an MND are offered consultations every 10th week during the course of the disease. Significant others and personal assistants are also invited to the consultations. Sixty-two patients were enrolled in the team during 2013.

Eligible patients for the study had an MND diagnosis [2] e.g. ALS, with both upper and lower motor neuron signs and symptoms, PLS with primarily upper motor neuron signs and symptoms or a motor neuron disease with primarily lower motor neuron signs and symptoms. The patients were not further classified into the specific El Escorial Categories [1]. Other inclusion criteria were ongoing pain, and sufficient communication skills for tape recording. Those with Kennedy's disease were excluded because of their symptoms of sensory impact and slow progress of the disease, which is distinctly different from the other MNDs [19]. Patients unable to understand and communicate in Swedish and patients cognitively affected and considered not to understand instructions and the purpose of the study were also excluded.

Procedures

A convenience sampling took place from September 2013 to October 2013. Physicians and nurses from the MND team helped identifying patients. Every patient who fulfilled the inclusion criteria were invited to participate in the study by the first author (YÅ) during an ordinary hospital visit to the MND team, or via a phone call. In total, 17 patients were eligible during this time period. Both oral and written information about the study were provided. The first author interviewed the participants individually, without presence from any relatives or other health care staff. The location was chosen by the participant, either in the hospital or at home. The interview took place in a separate room with minimal risk of being disturbed.

Demographic data were collected before the interview. A questionnaire covering family situation, occupational status and first symptoms were distributed alongside two measures, the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised version [20] and the Brief Pain Inventory Short Form [21].

The interviews lasted between 13 and 48 min and were all tape recorded. The differences in duration were mainly due to participants’ varying abilities to speak. The interview guide was developed by the research group in accordance with the aim of the study. An external colleague with experiences from qualitative research within physiotherapy and pedagogy reviewed the guide and came up with ideas for revision. The guide was then tested during the first scheduled interview. Since it worked satisfactory and did not result in any substantial changes, the interview was included in the final sample.

The interviews began with the following statement: “I know you have pain; can you tell me more about that?” Follow-up questions were related to the three pre-defined content areas covering experiences of a) presentation of pain e.g. “Can you describe the pain in your own words?” “How has the pain been during the course of the disease”? b) consequences of pain e.g. “What happens to you when you are in pain?” “How do you feel about it?” and c) management of pain e.g. “How can you reduce the pain?” “Which support do you get from health care”? Some participants spoke sparsely and needed prompts to bring out their answers. Confirmatory questions were also used to validate the understanding of participants’ pronouncements.

Ethics

The patients confirmed participation by signing an informed consent form and the study was approved by the Regional Ethics Committee in Uppsala, Sweden (approval No. 2013/288).

Data management and analysis

All interviews were transcribed verbatim by YÅ immediately after each interview. A portion of the transcribed texts were double-checked against the tape recordings by the third author (LZ). The interviews were read several times by YÅ and the second author (BJL) to get an overview of their content. The procedures described by Graneheim and Lundman [22] were followed during the analysis. First, data was sorted according to the three pre-defined content areas. The first and the second authors separately searched for meaning units and condensed them before checking the initial agreement. Second, YÅ and BJL separately labeled codes and grouped them into sub-categories and/or categories, which were subsequently discussed until an agreement could be reached. Third, YÅ and BJL agreed on the abstraction of categories into themes. Continuous researcher triangulation was used during all steps of the analytic procedure with all of the authors in a reciprocal process to ensure that no important information was missed and that the analytic steps were performed credibly. Table 1 offers an example of the process of condensation and gradual abstraction.

Table 1. Example from the analytic process of condensation and gradual abstraction.

Quotation	Code	Subcategory	Category	Theme
”Sometimes I sit up and try to stretch a little and then I am able to go back to sleep” (14).	Straighten out muscles during the night	Physical activities and movements	Strategies to endure pain	Successful coping with pain requiring personal effort and competent engagement.

Authors complemented each other with their various experiences. The last author (PÅ) contributed with extensive experience of patients with chronic pain as well as in qualitative research that applied qualitative content analysis. Three of the authors had extensive experience of MNDs (YÅ, LZ, BJL) and one of the authors (BJL) had a professional background as a nurse, whereas the other authors were physiotherapists (YÅ, LZ, PÅ).

Results

A total of 17 patients enrolled in the MND team from September 2013 to October 2013 fulfilled the inclusion criteria and were asked to participate; 16 accepted and 1 declined due to lack of interest in the study. The characteristics of the participants are shown in Table 2.

Table 2. Participant characteristics.

Partici-pant	Gender	Age	Family situation	Occupational status	Diag-nose	Time since first symp-tom of disease, year	Physical function^dALSFS-R total score	Worst pain^eBPI-SF	Least pain^eBPI-SF	Ave-rage pain,^eBPI-SF	^fPSI	^gPII (“walk” and “work” excluded)
1	Female	66	Married/cohabitant	Retired	^cPLS	12	34	7	0	5	4.3 (moderate)	5.1 (4.6)
2	Male	66	Married/cohabitant	Retired	^bMND	1.3	26	10	0	5	5.7 (moderate)	5.6 (6.2)
3	Male	58	Married/cohabitant	Working part-time	^aALS	1	32	9	0	0	3 (mild)	6 (4)
4	Female	66	Married/cohabitant	Retired	^aALS	2	23	4	0	3	3 (mild)	0.7 (1)
5	Female	58	Married/cohabitant	Working part-time	^aALS	3	33	5	3	3	3.7 (moderate)	4.7 (5.8)
6	Male	55	Married/cohabitant	Working full-time	^bMND	4	34	9	1	1	3.7 (moderate)	5.4 (4)
7	Female	61	Single	Sickness benefit	^aALS	1	17	7	1	5	4.3 (moderate)	3.1 (4.4)
8	Male	72	Married/cohabitant	Retired	^cPLS	30.1	34	5	0	2	2.3 (mild)	2.7 (2)
9	Male	71	Single	Retired	^bMND	2	35	7	0	2	3 (mild)	1.9 (2.6)
10	Male	48	Married/cohabitant	Working full-time	^aALS	3.1	37	10	0	2	4 (moderate)	4 (4.6)
11	Female	50	Single parent	Sickness benefit	^aALS	1.6	27	8	2	6	6.7 (severe)	5.4 (5.6)
12	Male	60	Married/cohabitant	Sickness benefit	^bMND	6	37	8	5	5	6.3 (moderate)	5.7 (6.4)
13	Male	71	Married/cohabitant	Retired	^bMND	5	43	4	0	4	3.3 (mild)	2.1 (2.6)
14	Male	47	Married/cohabitant	Working part-time	^aALS	0.4	32	8	0	4	4 (moderate)	5 (6)
15	Male	60	Married/cohabitant	Working part-time	^bMND	5	37	9	0	4	7 (severe)	2.7 (2.4)
16	Male	47	Married/cohabitant	Sickness benefit	^bMND	5	39	4	1	2	2.3 (mild)	2.7 (3.4)

^a Amyotrophic Lateral Sclerosis with both upper and lower motor neuron signs and symptoms that were not further classified into the specific El Escorial categories.

^b Motor Neuron Disease with lower motor neuron signs and symptoms but were not further classified into the specific El Escorial Categories.

^c Primary Lateral Sclerosis with only upper motor neuron signs and symptoms.

^d Amyotrophic Lateral Sclerosis Functional Rating Scale Revised version, a 12-item scale, which assesses the level of function in the five domains of speech, swallowing, fine motor function, gross motor function and breathing. 0 = total loss , 4 = normal function. Total score of maximum 48.

^e Brief Pain Inventory Short Form. Worst, least and average perceived pain intensity in the last 24 h. 0 = no pain, 10 = pain as bad as you can imagine.

^f Pain Severity Index is the average of the three BPI-SF items worst, average and current pain at the time of the interview. ‘‘No/mild” (0–3), ‘‘moderate” (4–6) and ‘‘severe” (7–10).

^g The Pain Interference Index is the average of the seven BPI-SF items on interference of pain with daily functions. 0: no interference; 10: interferes completely.

The results are presented below with respect to each content area, main themes and their underlying categories and subcategories. Key points are illustrated in the text by individual quotations. Table 3 provides a complementary overview of the themes, categories, and subcategories.

Table 3. Overview of themes, categories, subcategories and examples of quotations.

Theme	Category	Subcategory	Quotation
The multiple faces of pain	Multiplicity of pain perceptions	Multiplicity of pain characteristics and areas	“It itches a lot and especially in my eyes, and then it also hurt” (3).
		Pain is inconstant during days and nights	“…it happens every other night” (10).
		Pain alters over the course of disease	“It began two-and-a-half years ago and there was more pain then” (9).
The thin line between experience of pain and no pain	Exacerbation of pain	Physical strain	”I also have pain in my knee joint because I overstretch it” (8).
		Immobility	”I have felt pain when I lie very still at night” (13).
		Non-adapted equipment causes discomfort	“When I’m sitting and leaning against the backrest, just where the backrest meets my back…that is where it hurts” (15).
		Worrying has a negative impact	“Sometimes I’ve maybe felt a gastric ulcer because of my worries about the future. There must be a connection. That’s what I think” (2).
		Sense of bodily exhaustion	”My body is exhausted by the late afternoon/evening and I have screaming pain” (15).
		Physical touch is uncomfortable	“…massaging a little bit to make it better, but it gets even worse” (16).
The negative effects of pain on role functioning	Pain restricts physical function		“The pain itself makes you feel weaker. You lose your strength when it hurts” (16).
	Pain impacts activities of daily living		It is hard to move the head because it hurts in the neck in certain positions, especially when I eat. I need to think, because otherwise it gets even worse” (2).
	Pain restricts autonomy		“I can’t buy groceries by myself. I get pain when picking up groceries” (11).
	Pain impairs sleep quality		”When I sleep, I frequently wake up because of pain” (9).
	Pain creates powerlessness		”You know, I get fed up and give up; I can’t keep asking other people about things that I can’t do myself” (12).
	Pain produces a bad mood		“But now it’s getting to where it affects my mood. You get a little touchy when it hurts; you get in a bad mood” (8).
	Pain causes fear and anxiety		“It could press a little at the chest, here at the side, when I get dyspnea and it has developed. Then you get worried. Is it going to increase?” (4).
	Pain complicates fellowship and social life		“At five or six in the evening, or just after I’ve eaten or something, I’m not able to sit up anymore. My body is just screaming. That makes it hard to have a social life” (15).
Successful coping with pain requiring personal effort and competent engagement.	Strategies to endure pain	Physical activities and movements	”Sometimes I sit up and try to stretch a bit and then after that, I am able to go to sleep again” (14).
		Reduced exertion	”If that aching pain starts, then I have to rest; I have to lie down” (12).
		Modifying tasks to avoid pain	“…shave myself and go on for a while, then I get cramps here and there and have to change hands” (2).
		Adapted medication	”Now I take one pill three times a day but it’s not enough” (11).
		Sensory stimulation	“If I managed to prevent the cramp by pressing on it or lying in a certain position” (6).
		Individualised equipment	“I’ll also try the orthosis I got from the occupational therapist. Maybe it’ll provide relief” (3).
		Acceptance of pain	“I don’t know what to do, so I just have to accept it” (9).
		Competent and available support and advice	“I need to talk about some of them to find out what they are. It depends on whether you can do something about it, like this with the eyes. At home, if I have pain, I ask if I can take a tablet or whether it will disappear” (3).

The presentation of pain

Theme 1: The multiple faces of pain

Pain varied in many aspects, e.g., in character, perceived discomfort and location on the body. The pain came and went to various degrees and as the disease progressed. The presentation of pain varied from person to person, from time to time and within the same individual. Occasionally, pain was difficult for them to express. The participants described their individual perceptions of typical pain characteristics as follows:

“I get stabbing pains in my arms” (11).

“But I can tell you, it’s very intense, like cramp, it’s pretty bad” (6).

”…aching in my groins, mostly on the right, stiffness, heavy feeling…” (1)

”It’s like sharp needles of pain all the time” (2).

In addition to the sensory and bodily pain, pain was also expressed as being mental when symptoms appeared and brought attention back to the disease’s progression. Mental pain was also referred to in the perception of not being perfect and therefore becoming a burden to the relatives:

”On the other hand, I sometimes feel anxiety building up since I am constantly aware that something is going on all the time and that is pretty unpleasant. So that sort of pain is more like mental pain.” (5).

”If we’re talking about mental pain, I also feel pain as regards my family. That can be hard… you know, regarding my family members, I feel a bit guilty. I have that sort of pain since because I have the disease, I am upsetting other people.” (6).

The discomfort from pain varied. Some participants described the pain as a slight ache with minimal discomfort, while others described it as very intense, bringing about a sense of shock. The pain could be so intense that the person would sweat and nearly faint.

” I think the word “pain” sounds so dramatic. I feel some aching when I walk but I don’t know if I would call it pain.”(8).

”It was terrible, the cramping muscles that I had here, it was awful. Sweat was pouring off me; I nearly fainted.” (9).

Some participants described how the discomfort of pain could be a major nuisance and very stressful, while others described it as sufferable and that it could have been worse. Some participants expressed that they almost didn’t feel pain, but as the conversation progressed, they realized the opposite.

“Actually, now when I think about it, what I had forgotten about, I haven’t even mentioned the worst pain I have and that is when I wake up at night with cramp.” (6).

The perception of pain and discomfort could reflect the participant’s total disease situation. This was expressed as:

“In relation to my language problem, I would rather speak better” (3).

Pain could affect more or less the whole body, sometimes even the eyes. It could hurt in one part of the body, but also in several parts. Pain could also gradually spread to different parts of the body.

Pain was experienced at different times over a twenty-four-hour period. Some experienced pain upon waking in the morning; others experienced pain during the day or night. Sometimes the pain was present during the entire night and day:

”What I have in my neck is more like a continuous dull pain that I have all the time” (11).

For others, pain could appear once and only for a couple of seconds and then disappear.

During the disease trajectory, the pain was often described as changing in character and/or location on the body. The experience of pain also became worse and harder to endure as the disease progressed. Nevertheless, for some, pain was harder to endure in the beginning. Some participants even described having pain as the first appearance of the disease, for example, pain in the neck or cramps in the legs.

“For many years. That was how it started. I could feel that something was wrong. I thought I must have a weak neck and that was why I felt pain.” (11).

Theme 2: The thin line between experience of pain and no pain

Several aspects exacerbated the experience of pain. Margins were small relative to the pain threshold and pain breakthroughs could be hard to predict.

” …and now it’s almost gone or it has gone. So then you try to stretch a bit and then, bang, it comes back.” (6).

Participants mentioned that excessive physical strain could cause pain. Physical activities and exercise, e.g., walking too far or performing exercises for too long, caused pain, and so could daily activities like carrying things, cooking, eating, putting on clothes or being in a standing position. Abnormal ways of moving were aggravating, and some participants said that even very small movements, a change in position or yawning could provoke pain.

“I can even experience pain when adjusting the bedspread over me” (2).

On the other hand, immobility caused by involuntary static postures, non-adjusted furniture or un-fitted special aids increased the sensation of pain.

”It’s gotten worse since I started sitting in a wheelchair. Before, when I was sitting in the car, I could just straighten myself up and it would disappear” (8).

Tiredness and exhaustion, for example, at the end of the work week, could also exacerbate pain:

”It’s more when my whole body is really exhausted, and that happens especially on Friday or Saturday nights” (10).

The same was true of physical touch like massage or a passive movement on stiff joints, which could induce pain and discomfort rather than provide pain relief.

The consequences of pain

Theme 3: The negative effects of pain on role functioning

Pain affected participants physically, psychologically and socially, which impaired participants’ role functioning.

Physical function was negatively affected by pain. When participants avoided painful movements, their joints became stiffer. This physical restriction and impact on the fluency of movement could sometimes make movement impossible.

”It can be so painful that I’m reluctant to do it. It becomes hard to walk. When I feel a knock, my legs give way” (16).

Pain was described as making muscles feel weak and thereby draining physical reserves.

“The pain itself makes you feel weaker. You lose your strength when it hurts” (16)

Pain during activities resulted in limitations in daily life and during their spare time, participants described themselves as inactive. Leisure activities that hurt were omitted.

”…so now I sometimes feel I don’t want to do certain things because I know that then I will get a stab of pain” (5).

Furthermore, pain contributed to lost autonomy when it forced the need for assistance with daily activities like putting on clothes and performing housework. Sleeplessness due to pain was difficult and had a major negative impact, however, some participants got used to it.

”It would be nice to be able to wake up in the morning and feel rested because there are so many other things I need energy to do” (14).

“Well, I wake up but I have plenty of time; I can just go back to sleep and sleep a little during the day” (9).

Participants reported that pain caused psychological suffering when it reinforced a sense of being imperfect and created a sense of powerlessness, for example when they found themselves unable to manage a task as expected or avoiding difficult situations due to the expectation of worsened pain.

“No, there is certain powerlessness. If I lean against the backrest, it can cause pain, so I have to suffer for a while. And then I have to sit without support for my back, which you can only have the strength to do for a little while” (15).

Sometimes, participants felt there was no option other than to resign themselves to it.

“Well, of course, the best thing would be if it disappeared. I don’t know what else I can do during the night. It’s difficult” (14).

Pain could also contribute to bad mood and emotions like fear, anxiety and a sense of not being able to control or even understand the pain.

“…can’t open my eyes, because it hurts. It wouldn’t be good if that happened while driving a car if I were the one driving, but that hasn’t happened yet…but…” (3).

“… I felt something in my fingers and I thought, oh God, am I going to start feeling pain there as well.” (4).

In some situations, pain could affect fellowship and social life. This was exemplified by one participant who described how the pain became an obstacle to being able to continue walking with friends. This participant struggled with leg pain when walking and trying to keep up with a group, which finally became impossible.

”Well, you have to walk and walk and this group goes at such a fast pace, but I had been walking for two days and then the pain came straight away” (6).

The management of pain

Theme 4: Successful coping with pain requiring personal effort and competent engagement. Participants put a lot of effort into finding strategies for pain relief. The strategies changed from time to time and as the disease progressed.

“Then I just have to change position and that’s not so damned easy. I have to change the position of my legs and then it’s better for a while but then it comes back” (9).

”The worst thing I have experienced was when I had to get up for ten or fifteen minutes before I felt I was able to go back to bed again” (10).

If participants lacked sufficient knowledge about strategies or how to adapt them, they searched for, or got information and support from professionals and significant others.

Different kinds of movements were used for pain relief, either in physical activities or by separately moving joints. Being in water could be described as fantastic, even if only for a moment.

“I go to aqua-therapy. It’s only momentary relief but it’s so wonderful because then I have almost no pain at all” (11).

In addition to such active strategies, participants also rested in a reclined or seated position to reduce exertion and minimize pain caused by movement,

“The only time I don’t feel pain is when I am lying down” (11).

but sometimes the participants needed to change how they performed an activity to avoid pain.

Different kinds of medications were used with different continuity in intake, combinations and results. Changes in doses could reduce pain enough to be able to sleep, but the side effects were sometimes a reason to limit or eliminate the medicine.

“I am supposed to take between half a pill and a whole pill, but then if I take 10 milligrams as prescribed, then I get a slight hangover the next day, sort of fatigue syndrome. If I have an important work task I need to do straight away the next morning, then I won’t take one of those the evening before; I might put up with cramp during the night instead” (6).

Various types of sensory stimulation, such as transcutaneous electrical nerve stimulation and massage, could reduce pain in some phases of the disease, but were never described as stand-alone methods. Equipment to minimize pain included different orthosis, walking aids or the backrest of an armchair. To achieve an offloading effect, the equipment needed to be adjusted to fit the individual.

”I sort of half sit up, I’m not fully lying down and then I can feel that my back is properly supported and then I don’t get the pain, then the tenseness in my back stops” (4).

Participants described having to accept the presence of pain, especially when they had no alternative coping strategy. For some of those expressing acceptance, pain was perceived as a difficult and unpredictable obstacle that was impossible to affect, whereas others, after reaching a point of acceptance, perceived pain as a minor problem.

”I have pain. Well, what can I do? There’s nothing I can do” (12).

”I don’t feel the pain is so bad that I can’t put up with it” (5).

When the pain changed or became worse, participants sought information and support from significant others or medical staff, which helped them to choose the right pain relief strategy. However, advice from healthcare was sometimes insufficient or unavailable,

“I don’t really know what else I can do. But nobody has really asked me about the question of pain; I have had to bring it up myself” (11).

and the participants did not always raise the question of how to handle the pain.

“Initially, I didn’t really know what was available and I’m the sort of person who can put up with quite a lot and I don’t like to be a nuisance” (11).

Some participants expressed that, in hindsight, they needed more support.

Discussion

To our knowledge, this is the first study exploring personal experiences of pain as perceived by people with MND. The study provides new knowledge on individual variation in the presentation of pain and stressful experiences of pain, which could be used to inform development of disease-specific pain assessment methods and pain treatments. At first glance, the experiences of study participants confirm previous findings regarding variation in pain characteristics, pain location, pain intensity, and prevalence of pain over the course of the disease [9,10,23]. They also point out that pain is associated with deterioration of quality of life manifested by impaired role functioning, loss of autonomy and grief, the latter expressed as “mental pain”. Associations between quality of life and pain have been identified earlier [8,15], but also questioned due to its co-morbidity with depression [7,13].

An important new finding was the experiences of unpredictability of pain breakthroughs. Very intense pain could appear suddenly, as if from nowhere, lasting for a short while, and then fade away just as quickly. This could happen several times over the course of 24 h. Fluctuating pain, often characterized as a cramp or spasm, has previously been reported in ALS [8,10,24], but the high frequency of sudden breakthrough pain episodes over the course of one day and night is a new insight. The participants described these events as strenuous and tough, especially at night, indicating that pain flare-ups are salient stressors that need further attention. Overall, there was a seemingly thin line between experiences of no pain and breakthrough pain. Similar to our findings, previous studies have reported movement as well as immobility as being aggravating [8]. In addition, our participants referred to that sense of bodily exhaustion, use of badly adapted equipment, and worries could provoke pain flare ups. Interestingly, also minor physical strains such as small movements and changes in loads, and even physical touch could provoke pain, which contributed to its unpredictability. Taken together, these experiences indicate different causes of pain, which may require individually tailored pharmacological as well as non-pharmacological treatments, that is, evidence suggesting that pain in MND should not be treated according to the patient-uniformity myth assuming that all persons with pain and MND are a homogenous group [25].

Some of the participants identified pain as the first symptom of their disease, a phenomenon that was been documented three decades ago [26,27], although no studies on causality have yet been identified. In the hitherto largest survey on ALS and pain, 50% reported that pain started before ALS onset, 82% that the pain experienced was due to ALS and 34% that pain was a presenting symptom of ALS [12]. Our results validate that pain may be either (1) a representation of the disease, (2) a consequence of disease-related factors, e.g., cramps, spasticity, and immobility, or (3) both.

Some participants almost denied pain despite discomfort. The reasons behind this neglect differed between persons. It seemed to be driven by the overall situation, where discomfort from pain in some cases was a minor nuisance compared to other worse aspects of the disease. This corresponds well to the results presented by Hecht and colleagues [28] who found that pain seldom was reported as the worst and most important aspect of the disease. Other participants had bad experiences of not having received any help for their pain, and some had even decided not to mention their pain due to the belief that it was no use since there was no cure for the disease or for the pain. To the best of our knowledge studies on under-reporting of pain is missing in MND. Drawing a parallel to cancer care, where it is well-known that pain is bot underreported, underdiagnosed, and undertreated, the reason for diminishment and under-reporting of pain might be found in patients’ and care givers’ attitudes and behaviors rather than in a lack of treatment options [29]. This makes a case in support of measures from caregivers regarding pain assessment and adequate pain management. If patients and informal care-givers are routinely informed about possible treatment options, they may be more inclined to tell about the pain. Further, guidelines for systematic pain assessment in MND are warranted [12]. Such guidelines could be used to avoid physicians’ and care-givers’ bias when identifying candidates for pain treatment. However, available pain assessment methods must be reviewed in terms of validity for the presentation and subjective perception of pain in persons with MND. This study provides some information that could be used in the development of future condition-specific or patient-specific pain measures.

Participants described in detail how pain interfered with essential activities of daily living, for example, when pain in the neck made it impossible to eat. Wallace et al. [8] showed that the level of pain interference in activities of daily living is correlated with severity of pain in ALS, whereas Stephens et al. [12] showed that pain intensity did not correlate with pain interference, suggesting that pain itself but not its severity necessarily determines one’s activity level. The experiences of the participants were that pain per se had a negative impact on social role functioning, autonomy, physical function, psychological well-being and life-supporting activities. The extensive variation in these experiences may explain why the relationships are difficult to quantify and refine.

A new insight is that coping strategies were taxing and demanded personal engagement for the pain not to exceed its threshold or to achieve pain relief. This leads to further questions about possible associations between the price for and personal effort to find adaptive coping strategies and in which situations the effort is aggravated. Emotions are highly integrated with the experience of pain and negative emotions and feelings often worsen pain [30]. Participants described the acceptance of pain, or emotion-based coping focused on regulating feelings about pain rather than tackling the pain per se. With an increased understanding of emotions associated with painful situations come options for possible treatment [30], which highlights the importance of non-pharmacological treatment such as psychological interventions. Some participants in our study seemed resigned to their pain, and did not have the fortitude to ask for help from health professionals. Consequently, this is an area for improvement in the care for people with MND.

Methodological considerations

The results of this study need to be interpreted while considering the strengths and limitations of the qualitative study design. The methods enabled participants´ free, verbal pronouncements and allowed personal experiences to be explored in a way that have not been possible in previous studies on pain in MND using established pain measurements. The participants were able to describe situations and experiences that were personally relevant and because of this, it was possible to further explore the nature and consequences of pain. The method made comparisons between earlier quantitative results and personal experiences of pain possible, in addition to making essential knowledge for the development of new pain assessment and pain management strategies possible. Nevertheless, there were some limitations that need to be considered. The sample size was determined in accordance with what the research group regarded as a reasonable amount of data to handle in this study context given the available resources, which could be criticized with respect to saturation. We cannot with certainty claim that data saturation was reached due to the lack of strict criteria. Nevertheless, as a result of researcher triangulation, we concluded that data was rich and adequate and that a larger (thicker) amount of data would not necessary result in new codes and different answers to the research question. Further, we have provided information making it possible to replicate the study [31].

The settings for the selection of participants were limited to one specialist team in a university hospital in Sweden, which may reduce the variation in experiences and thus the transferability to patients from other settings. Another limitation was the exclusion of individuals incapable of verbally expressing themselves, which often represents a more advanced disease progression in motor neuron diseases [2]. This may further reduce the transferability of results. Further, patients that were cognitively affected were excluded, although these are of particular interest since cognitively affected individuals with Alzheimer’s disease seem to have an increased tolerance for pain [32,33].

The fact that the interviewer (YÅ) used to work as a physiotherapist in the MND team may have influenced the participants’ sharing. However, the content areas for interview were not explicitly associated with the physiotherapist´s role in the specialist team. On the contrary, the interviewer’s experiences concerning the participants´ disease may have contributed to the participants being able to trust that the interviewer was experienced and well-acquainted with the disease and to the interviewer being able to understand them in spite of their speech problems. Hence, participants did not need to explain the disease itself and instead could focus on personal experiences of pain. Only one individual declined to participate, and even participants who were clearly affected by their illness agreed to be interviewed. Finally, as triangulation was performed with a member without extensive knowledge about the disease, preconceptions were constantly discussed and challenged. To enhance the credibility of the analysis, the analytic track is presented for each theme, category and subcategory in Table 3 and quotations are presented in the text.

Ethical considerations

A possible risk associated with participation in this study was that the patients could have felt compelled to participate, as in the case of YÅ, who was responsible for recruitment to the study and was previously employed as a physiotherapist in the specialist team. Another estimated risk was that the participants could be upset during the interviews as the conversations encouraged them to reflect upon his/her disease and current life situation. However, the benefits of being listened to and the wish for contribution to research about an aspect of motor neuron diseases that is seldom cared for was believed to exceed these risks.

Implications for pain assessment and pain management

Based on patients’ experiences of pain in MND, we propose that pain measurements in MND should include a time frame long enough to cover fluctuations of pain. Hence, questions about current pain should be omitted or complemented with questions about pain in a longer time frame, e.g., the last week. Further, pain assessment methods ought to capture pain variation over the entire night and day. The number of pain flare-ups, their length and intensity and context should be quantified, and pain-free hours and situations should be registered. Such pain monitoring requires modern pain assessment methods which could be developed by use of digital solutions and artificial intelligence. The latter has the potential to make pain assessment methods patient-specific rather than generic, which seems to be crucial considering the individual experiences, and the multiple faces of pain.

There is a need for health care professionals involved in the care of patients with MND to support patients’ opening up about their pain, and making sure that proper pain management strategies are provided. This should be done during the entire course of the disease, i.e., from diagnosis to the terminal stages. Since some participants in our study shared about their diminishment of pain symptoms, we propose that health care professionals should consciously validate the experience of pain and refer to their experiences of pain being a nuisance related to the disease. They should also offer information about the pain being possible to treat successfully with medication, by contrast to the possibility of curing the disease itself.

Non-pharmacological pain management strategies should also be considered, e.g., the adaptation of auxiliary means and orthotic devices with the explicit goal of obtaining pain relief. Today these means are often adequate in support of physical function, whereas adaptation for pain relief could be improved. Strategies for activity planning are also proposed to find means that facilitate the performance of necessary yet painful activities as much as possible, and thereby enhance possibilities for persons with MND to engage in personally prioritized activities of importance for individual quality of life.

Conclusion

In conclusion, this qualitative study showed that pain in MND has multiple faces and that its occurrence is hard to predict over the course of the disease, as well as during such a short period as one night and day, according to persons afflicted. Since pain in MND seems to have certain characteristics, there is a need to develop and implement pain assessment methods adapted to the MND population. Such methods may help make pain more predictable, and increase the possibilities for effective pain management.

There are reasons to believe that patients opt out of sharing about their suffering from pain, and why the initiative must come from health care staff responsible for care. This requires knowledge of pain medicine and multidisciplinary pain rehabilitation strategies, which should be stressed in clinical guidelines covering the entire course of disease, i.e., from diagnosis to the palliative phase.

Disclosure statement

The authors report no conflicts of interest.

Additional information

Funding

This work was supported by the County Council of Uppsala; the funding of agreements on medical education and research Uppsala University Hospital, the Uppsala University medical faculty’s funding for caring sciences, and the Neuro Federation of Sweden.