Abstract
Background. Two conceptually different morbidity outcomes unmet needs and health-related quality of life are used to identify cancer patients in need of clinical attention and to evaluate rehabilitation programmes. The knowledge on the interrelation between unmet needs and health-related quality of life is scarce. This paper studies the hypothesis that patient-perceived unmet needs of rehabilitation during the cancer trajectory are associated with decreased quality of life. Material and methods. Based on registers, a Danish population-based cohort of adult, incident, mixed-site cancer patients diagnosed between 1 October 2007 and 30 September 2008 was established. At 14 months following diagnosis participants completed a questionnaire including health-related quality of life (EORTC QLQ C-30), psychological distress (POMS-SF), and unmet needs with regard to physical, emotional, family-oriented, sexual, work-related, and financial problems. Unmet needs were assessed through six ad hoc questions. Results. Questionnaires were received from 3439 of 4947 patients, resulting in a response rate of 70%. The three most frequent cancer types were breast (28.4%), prostate (14.6%) and colorectal cancer (15.2%). Overall, 60.1% expressed an unmet need of rehabilitation in at least one area, physical and emotional problems being the most frequent (40.0% and 37.5%). For all scales of the EORTC QLQ C-30 and POMS, significant adjusted mean differences were observed between patients with unmet needs in at least one area and patients with no unmet needs (p-values < 0.001). These differences were well above levels usually considered clinically relevant. Further, impairment increased with increasing number of areas in which unmet needs were reported. Discussion. We confirmed the hypothesis that patient-perceived unmet needs of rehabilitation during the cancer trajectory are associated with decreased quality of life. This study supports the use of unmet needs questions to identify patients in need of clinical attention. Interventions reducing cancer patients’ perceived needs of rehabilitation may enhance quality of life.
Cancer patients face various symptoms related to their disease and treatment, such as fatigue, depressive symptoms, lymphedoema and other bodily changes [Citation1,Citation2]. Anxiety and fear of recurrence may be overwhelming. Physical, psychological and social problems may thus affect daily functioning in a way that reduces health-related quality of life [Citation3]. Cancer rehabilitation addresses these problems and aims to enhance daily functioning and quality of life through different professional interventions. Psychological counselling, physical training, information, assistive technologies, pain, fatigue and depression reductive strategies are examples of the wide variety of interventions that may be needed. Cancer patients expect the healthcare system to be aware of their cancer-related problems during treatment and follow-up [Citation4–6]. However, studies of different cancer groups have shown that often these problems are not appropriately addressed by professionals, which may give rise to the perception of unmet needs of rehabilitation [Citation2,Citation7]. Patients frequently report that they have not received the desired support during treatment and follow-up [Citation1,Citation2,Citation8].
Two conceptually different morbidity outcomes, unmet needs and health-related quality of life, are used to identify cancer patients in need of clinical attention and to evaluate interventions for cancer patients [Citation9,Citation10]. Unmet needs refer to patients’ experiences with individual help from professionals in the past and covers a range of issues, whether conceptualised as rehabilitation, supportive care, palliation or follow-up. The relation between unmet needs and health-related quality of life is an important issue in cancer research. However, knowledge on the interrelation between unmet needs and health-related quality of life is scarce. A better understanding may improve the design and evaluation of interventions, and the construction and interpretation of needs assessment instruments used in clinical research and routine practice.
The present large-scale study aimed at analysing the hypothesis that patient-perceived unmet needs of rehabilitation during the cancer trajectory are associated with decreased quality of life.
Methods
Based on registers, a population-based cohort of adult, incident, mixed-site cancer patients diagnosed between 1 October 2007 and 30 September 2008 in two of the five Danish Regions was established. A mailed questionnaire survey 14 months following date of diagnosis provided information on health-related quality of life, psychological distress, and unmet needs with regard to physical, emotional, family-oriented, sexual, work-related, and financial problems. The study was approved by the Danish Data Protection Agency (file number 2008-41-1887) and the Danish National Board of Health. According to the Regional Scientific Ethics Committee, the Biomedical Research Ethics Committee System Act does not apply to this project.
Setting
The Danish healthcare system is primarily publicly funded [Citation11]. More than 98% of the population is listed with a general practice. General practitioners act as gatekeepers to most parts of the healthcare system. The municipalities are responsible for cancer rehabilitation at the general level, while hospitals are responsible for highly specialised cancer rehabilitation. Rehabilitation provided by the public healthcare system and the municipalities is free of charge. Furthermore, private patient organisations offer free support, and private physiotherapists, psychologists, and alternative practitioners etc. offer their services for a fee.
Study population
The study population has been described in detail in a previous paper [Citation12]. Briefly, the Regions of Southern and Central Denmark have 2.4 million residents. By use of the regional hospitals’ Patient Administrative System all 18+-year-olds with a cancer diagnosis (ICD-10 codes DC00-96, DD37-48) registered within the one year inclusion period were identified. By linkage with the National Patient Registry, patients with non-incident cancer and patients not registered with a general practice were excluded. For each patient, the general practitioner was asked to confirm the cancer diagnosis.
Patient questionnaire
A 171-item patient questionnaire was developed to feed several studies on rehabilitation among adults with different cancers [Citation12,Citation13]. Included in this study were questions on health-related quality of life, psychological distress, and unmet needs with regard to physical, emotional, family-oriented, sexual, work-related, and financial problems. Further, the questionnaire included questions on need for professional help in the different areas of unmet needs, participation in rehabilitation activities, perceived continuity of the cancer care, satisfaction with the general practitioner and the health care system during the cancer trajectory, health locus of control, and religious and spiritual beliefs [Citation13]. The process of questionnaire development and pilot testing has previously been described [Citation12,Citation13]. The pilot test followed a three-step procedure where each step gave rise to additional revision. Firstly, health researchers were asked to comment on content, layout, volume and intelligibility of the draft. Secondly, 10 cancer patients at the oncological ward at Odense University Hospital were asked to fill in the questionnaire under observation of a researcher and comment on content, layout, volume and intelligibility. Thirdly, a group of 100 cancer patients were asked to fill in a mailed version, enabling the examination of discrimination and acceptability. The overall participation rate of this last phase of the pilot test was 75%. At 14 months following date of diagnosis patients were invited for this survey and had the questionnaire sent by mail [Citation12]. Questionnaires were mailed monthly which ensured that patients were invited close to 14 months following date of diagnosis. Reminders were sent after two to four weeks following the invitation.
Data on unmet needs of rehabilitation
Ad hoc questions were developed to assess unmet rehabilitation needs in six different areas, i.e. the physical, emotional, family-oriented, sexual, work-related and financial [Citation12]. The six questions covering these areas were asked in connection with questions on need for professional help and were formulated similarly in all areas. For example, patients were first asked whether they had needed professional help with physical problems, and secondly they were asked the question used in this study: “Until now, to what extent have you had your needs fulfilled in terms of help with physical problems?” Response categories were ‘not at all’, ‘to a small extent’, ‘to some extent’, ‘to a great extent’ and ‘not relevant’. Until now referred to the period of being a cancer patient, i.e. the previous 14 months.
Data on quality of life
Quality of life was measured as health-related quality of life by use of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C-30 (EORTC QLQ C-30), and psychological distress by use of the Profile of Mood States-Short Form (POMS-SF). The questions on health-related quality of life and psychological distress referred to the previous week.
The EORTC QLQ C-30 consists of 30 items, measuring 15 aspects of health-related quality of life in patients with various types of cancer. It includes the global health status, five functional scales (physical, emotional, role, cognitive and social functioning), three symptom scales (fatigue, nausea/vomiting and pain) and six single symptom items (dyspnoea, insomnia, appetite loss, constipation, diarrhoea and financial difficulties) [Citation14]. Each item is scored 1 to 4 according to the categories ‘not at all’ (1) to ‘very much’ (4), with the exception of the global health status which is scored 1 to 7. Mean scores are linearly transformed to 0–100 scores. High scores represent healthy functioning in the functioning scales and global health status, but a high level of problems for symptom scales and single symptom items.
The general psychological distress questionnaire POMS-SF consists of a list of 37 adjectives. Respondents indicate the degree to which each adjective describes their mood during the previous week using a five-point Likert scale from ‘not at all’ (0) to ‘extremely’ (4). The POMS-SF consists of six subscales (depression/dejection, anger/hostility, tension/anxiety, vigour/activity, fatigue/inertia and confusion/bewilderment), which can be used to calculate the total mood disturbance score [Citation15]. Mean values of the subscales depend on the number of items in the respective subscale which varies from 5 to 8. Total mood disturbance is calculated as the sum of the scores of the five negative subscales subtracting the score of the one positive subscale (vigour/activity). A high score of the total mood disturbance score and five of the six subscales indicates a high degree of distress. A high score of the vigour/activity subscale indicates a low degree of distress.
Statistical analysis
For each area of unmet needs, responses to the question “Until now, to what extent have you had your needs fulfilled ….” were dichotomised into ‘unmet needs’ (not at all/to a small extent/to some extent) and ‘no unmet needs’ (to a great extent/not relevant). Two additional variables ‘unmet needs in at least one area’ (dichotomous) and ‘number of areas in which an individual reported unmet needs’ were constructed. Missing data of the EORTC QLQ C-30 and POMS-SF were regarded as missing at random. No imputations were made for missing values. Completion rates were calculated for each of the EORTC and POMS outcomes and for each of the six single items covering unmet needs. Cronbach's α was used to assess the internal consistency of the composite scales and subscales of the EORTC and POMS.
Associations between unmet needs and health-related quality of life/psychological distress were analysed using linear regression. In order to take confounding into consideration the analyses were adjusted for sex, age (three age groups), and cancer diagnosis. The number of areas with unmet needs was treated as a categorical variable due to a non-linear relationship with health-related quality of life/psychological distress. Mean scores and mean differences of EORTC QLQ C-30 and POMS measures are shown with 95% confidence intervals (CI) in brackets.
Results
Of the 4947 subjects eligible after 14 months, 3439 returned the questionnaire (70%). The three most frequent cancer types were breast (28.4%), colorectal (15.2%), and prostate cancer (14.6%) (). In total 57.4% were female, and 52.7% were younger than 65 years. Overall, 60.1% expressed an unmet need of rehabilitation in at least one area, unresolved physical and emotional problems being the most frequent (40.0% and 37.5%) ().
Table I. Characteristics of participants in a Danish cohort study of cancer rehabilitation, 14 months following the diagnosis of cancer. The frequencies of the different unmet needs include distribution by sex, age and cancer diagnosis.
The mean score of the EORTC QLQ C-30 Global Health Status was 71.8 (95% CI 71.1–72.6%). Linear regression analyses showed that unmet needs in at least one area were associated with low quality of life according to EORTC QLQ C-30 (). Adjusted mean differences between patients with unmet needs in at least one area and patients with no unmet needs were statistically significant for each of the 15 health-related quality of life scores (p-values < 0.001) (). The adjusted mean differences for the functional subscales varied from role functioning −15.0 (−17.0, −12.9) to physical functioning −10.0 (−11.4, −8.6).
Table II. Associations between health-related quality of life (EORTC QLQ C-301) and perceived unmet needs in at least one area, 14 months following a diagnosis of cancer.
The mean score of the POMS-SF total mood disturbance score was 5.7 (4.9–6.4). Linear regression analyses showed that unmet needs in at least one area were statistically associated with more psychological distress on each of the six subscales and the total mood disturbance score (p-values < 0.001) ().
Table III. Associations between psychological distress (POMS-SF1) and perceived unmet needs in at least one area, 14 months following a diagnosis of cancer.
Unmet needs in one area frequently meant unmet needs in other areas (). Unmet needs in three or more areas were reported by almost one third of the study participants (31.8%, 95% CI 30.2–33.3%), and by the majority of the patients with unmet need in at least one area (52.9%, 95% CI 50.7–55.0%). Impairment according to global health status (EORTC) and total mood disturbance (POMS-SF) increased with increasing number up to five areas in which unmet needs were reported [the adjusted differences decreased to -18.7 (-21.6, -15.8) and increased to 19.2 (16.2, 22.1), respectively] ().
Table IV. Associations between health-related quality of life and psychological distress and number of areas with unmet needs among cancer patients, 14 months following diagnosis.
Of the 3439 study participants who returned the questionnaire after filling it in, the completion rate of the unmet needs items was around 93% [from 92.5% (sexual area) to 93.5% (emotional area)]. The proportion of complete cases of the EORTC scales and items was around 94% [from 92.7% (role functioning and emotional functioning) to 94.7% (diarrhoea and insomnia)]. The proportion of complete cases in the POMS subscales varied from 88.5% (vigour/activity) to 91.0% (tension/anxiety), and the proportion of complete cases in the total mood disturbance score was 79.7%. The Cronbach's α of the composite subscales of the two quality of life scales varied from 0.70 to 0.91 (EORTC) and from 0.86 to 0.93 (POMS).
Discussion
This cohort study of 3439 adult mixed-site cancer patients confirmed the study hypothesis that unmet needs of rehabilitation during the cancer trajectory are strongly associated with reduced quality of life 14 months following a diagnosis of cancer. Unmet needs were significantly associated with all aspects of health-related quality of life and psychological distress. The results indicated clinically relevant differences between patients reporting unmet needs compared to patients with no unmet needs. A total of 60% expressed unmet needs in at least one area, and unmet needs in several areas were frequent.
The size and diversity of the study population with regard to age, cancer type, cancer stage and treatment, and the high response rate strengthen the generalisability of the study results. The slight overrepresentation of women, the 60–69-year-olds and patients with breast cancer among responders is not expected to bias study results [Citation12].
Both the EORTC QLQ C-30 and POMS-SF scales are valid and reliable instruments widely used to assess health-related quality of life and psychological distress in cancer patients [Citation10,Citation16]. The internal consistencies in this study were high. Missing rates of the EORTC are generally expected to be less than 2% [Citation14]. They were a little lower in this survey (completion rates around 94%), which may be due to the overall length of the questionnaire. Existing supportive care needs questionnaires such as the Short-form Supportive Care Needs Survey (SCNS), a 34-item questionnaire, were not considered appropriate for the overall goals of the survey [Citation9,Citation12]. Questions were designed to cover types of needs relevant for a broad cancer population during the first years of cancer. Health information to cancer patients has been shown to be inadequate [Citation1,Citation17]. In this survey health information needs were not asked for specifically, but indirectly in the six areas: physical, emotional, family oriented, sexual, work-related and financial. Based on the development phase of the questionnaire, pilot testing and response rates of single items, the questions were assumed to be acceptable and interpretable in all areas, although specific information needs may have been underestimated. However, a 14-month time frame is a long period and recall bias could have affected the results. For example, with increasing functioning and quality of life at the time of the survey patients might overlook previous experiences of unmet needs. Unlike the questions on unmet needs, the questions on health-related quality of life and psychological distress referred to the week prior to the questionnaire being filled in. The different recall periods are not regarded a weakness of the study. The results underline the fact that not being met by the help considered to be needed affects quality of life in the long run.
The category ‘no unmet needs’ most likely included some patients with symptoms and impaired functioning. Some of these patients may have felt satisfied with their care, not perceived the symptoms or limitations as bothersome, or they did not want help from professionals [Citation17,Citation18]. This could have weakened the results of our study. However, we found large mean differences in the EORTC QLQ C-30 and POMS-SF scores between patients with one or more unmet needs and patients with no unmet needs. These differences are well above levels usually considered clinically relevant in clinical trials [Citation15,Citation19]. The different health- related quality of life indicators of the EORTC QLQ C-30 are known to be interrelated [Citation16], but the concordant direction of the associations and the sizes of the differences observed strengthen the study results.
To study the association between health-related quality of life and increasing number of areas with unmet needs, we simply counted the areas in which the patient perceived unmet needs. This approach assumes that all areas are equally important, which may not be true. Up to a number of five unmet needs, functioning decreased steadily. This suggests that an increasing number of unmet needs have an effect on health-related quality of life, even though they may not be equally important. Further research may answer how the different unmet needs affect the different dimensions of quality of life.
Patients were asked 14 months following the diagnosis of cancer, i.e. at a time when the majority had completed the primary cancer treatment and had entered into a new trajectory of self-care and readjustment. Future studies may show if the strong associations between unmet needs and quality of life persist during late survivorship and palliation.
One study limitation is the cross-sectional design. The self-assessment and the measurement at one point in time might have biased the answers, since impairments in health-related quality of life may impact the experience of unmet needs in a negative way and vice versa, e.g. patients with low health- related quality of life may feel more dissatisfied with prior supportive healthcare. Thus, considerations on causal inferences between unmet needs and quality of life and psychological distress require great caution. It should be underlined that the study was not designed to answer if interventions aiming to reduce the number of perceived unmet needs increase health-related quality of life.
The observed association between unmet needs during the early cancer trajectory and low health-related quality of life is in line with two cross-sectional studies from oncology settings [Citation20–22]. A Japanese study of 408 ambulatory female patients with breast cancer found a significant association between the global health status of the EORTC QLQ-C30 and each need score of the SCNS (the global score, psychological, health system and information, physical and daily living, patient care and support, and sexuality) [Citation20]. Quality of life subscales were not analysed. Psychologically distressed patients reported more unmet needs (distress was measured using the Hospital Anxiety and Depression Scale, HADS). Studies from the US of a relatively small convenience sample of 117 breast, prostate, and lung cancer patients concluded that needs assessment can be used to identify patients with critical health-related quality of life, requiring attention from clinicians [Citation21,Citation22]. Our large-sized study of a mixed cancer population from a European setting thus supports the limited evidence that unmet needs are an important indicator of quality of life in the early survivorship phase for a broad group of cancer patients.
Asking patients if they, so far, had received the support from healthcare providers they needed, can be used to identify target groups for interventions, i.e. patients with low quality of life. Further, this type of questions may be useful as screening questions for guidance in clinical decision-making, e.g. on further diagnosis, inclusion in trials, or referrals to hospital- or community-based rehabilitation. It may seem tempting that patient questionnaires filled in before the consultation inform clinicians and thereby facilitate the discussion of the most needed items. However, the evidence of this type of feedback is inconsistent, in general as well as in cancer settings [Citation23–26]. Effects of screening on clinical decisions, processes or outcomes of patient care require a series of mechanisms that link the intervention with its expected outcomes [Citation23–25]. It should therefore be noted that isolated recommendation of specific patient questionnaires for routine screening is insufficient to facilitate a change of important outcomes.
Although the causal relationship between patient-perceived unmet needs and quality of life is not known, this study supports the view that interventions to reduce patients’ perceived needs may be a promising strategy for enhancing quality of life of cancer patients. Future studies may investigate whether addressing unmet needs through interventions increases quality of life. The observations that additional unmet needs increase the burden experienced by patient, and that unmet needs in different areas frequently coincide are important when designing or evaluating cancer rehabilitation and supportive care. Although symptoms are multiple, trials often selectively focus on one specific problem or functional perspective. This study underlines the fact that interventions should target both the multidimensional impact of cancer on daily living and the multiplicity of unmet needs that burden the majority of patients in need. Trials often fail to show clinically relevant differences in the primary outcome health-related quality of life [Citation10]. This study suggests that interventions may disappoint with regard to quality of life outcomes, since patients still perceive unmet needs in areas not targeted by an otherwise effective intervention. Informing patients about the complexity of problems and needs may be helpful to increase the benefit of participation in rehabilitation offers.
Conclusion
Unmet needs of cancer rehabilitation are strongly associated with quality of life. This study adds evidence to the use of unmet needs questions to identify cancer patients in need of clinical attention. Needs in one area often coincide with needs in other areas. Taking into account the complexity of needs perceived by cancer patients should be an important issue for clinicians and for those designing interventions.
Acknowledgements
The research groups wish to thank all patients for participating in the study. The authors wish to thank Lise Keller Stark, Research Unit of General Practice, University of Southern Denmark, for proofreading the manuscript.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
This study was funded by the Danish Cancer Society and the Novo Nordic Foundation. The National Research Centre for Cancer Rehabilitation is funded by the Danish Cancer Society. The authors report no conflicts of interest.
Related Research Data
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