Relationship between Distress Related to Caregiver Burden and Physical Activity in Informal Caregivers of Patients with COPD

Abstract

Chronic obstructive pulmonary disease (COPD) can lead to increased dependence on the informal caregiver and, consequently, to distress associated with caregiving burden. In the general population, higher levels of physical activity (PA) are related to lower distress levels; however, this relationship has been scarcely studied in COPD. This study aimed to explore the relationship between distress and PA in informal caregivers of patients with COPD, and the influence of caregivers’ (age, sex) and patients’ (age, sex, lung function) characteristics and caregiving duration on this relationship.

A cross-sectional study was conducted with 50 caregivers (62.7 ± 9.8 years, 88% female; 78% caring for a spouse/partner; 38% caring >40 h/week; patients’ FEV₁=45.2 ± 21.3% predicted). Data collection comprised questions related to the caregiving context, distress related to caregiving burden assessed with the Informal Caregiver Burden Assessment Questionnaire (QASCI; total score, 7 subscales), and self-reported PA with the Habitual Physical Activity Questionnaire (HPAQ). Spearman’s correlation coefficient and linear regressions were used.

Significant, negative and moderate correlations were found between the QASCI (28.5 ± 19.8) and the HPAQ (5.2 ± 1.3) (ρ=-0.46; p = 0.01); and between the HPAQ and some QASCI subscales (emotional burden ρ=-0.47; implications for personal life ρ=-0.52; financial burden ρ=-0.44; perception of efficacy and control mechanisms ρ=-0.42; p < 0.01). Two linear regression models were tested to predict QASCI total score including as predictors: 1) HPAQ alone (p = 0.001; r²=0.23); 2) HPAQ and caregiving h/week (p < 0.001; r²=0.34).

Higher self-reported PA levels are related to decreased levels of distress associated with caregiver burden in COPD caregivers. Duration of caregiving may negatively influence this relationship.

Keywords:

• Chronic lung disease
• chronic obstructive pulmonary disease
• daily activity
• disease burden
• family caregiving
• informal care

Introduction

Chronic Obstructive Pulmonary Disease (COPD) is characterized by persistent respiratory symptoms and airflow limitation [1]. Most common symptoms include dyspnea, cough and/or sputum production, associated with a progressive loss of independence and quality of life [1] which increase the patient's dependence on the caregiver [2,3]. An informal caregiver is someone who provides unpaid assistance to a family member or friend who is unable to manage their daily life independently and who may or may not be living with the person receiving care [4–6].

Caring for an individual with COPD may be related to significant physical, psychological, emotional, social and financial challenges which, over time, may lead to caregiver burden [3,7]. This burden results in the occurrence of pathological stress, also known as distress, which is common in caregivers of individuals with chronic diseases such as COPD [8].

Four domains have been suggested to explain the process of stress development in informal caregivers: the context of stress, primary and secondary stress-inducing agents, stress mediators, and stress effects [5]. According to this model, physical activity (PA) can be considered a stress mediator, as it can influence the stress levels [5]. Physical activity includes not only exercise (a planned and structured type of PA) but all everyday activities that require movement and energy expenditure [9]. PA and exercise lead to biological adaptations that contribute to a reduction in the physiological reaction to stress, which is induced by high cortisol levels [8]. However, the higher the distress levels, the less likely the individual is to be available for PA [10]. Thus, a decrease in distress levels may encourage regular practice of PA, and vice versa [10].

The relationship between PA and distress is known in the general caregiver population [10,11]. However, this relationship still needs to be explored in the specific population of informal caregivers of individuals with COPD. Therefore, this study aimed to explore the relationship between distress associated with caregiver burden and self-reported PA levels in informal caregivers of patients with COPD. Specifically, it was hypothesized that higher levels of distress were related to lower self-reported PA levels. A secondary aim was to explore the influence of caregivers’ (age, sex) and patients’ (age, sex, lung function) characteristics and caregiving duration on this relationship.

Methods

Study design

This was a cross-sectional study. Ethical approval was obtained from the Ethics Committee of the Polytechnic Institute of Leiria (CE/IPLEIRIA/14/2018) and the Leiria Hospital Center (07/11/2018). Approval to use the questionnaires about caregiver distress and PA was obtained from the authors of the Portuguese version of the questionnaires. This paper follows the guidelines for STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) [12].

Participants

The target population were individuals with the role of informal caregivers of patients diagnosed with COPD living in the community. Recruitment was carried out at the Respiratory Research and Rehabilitation Laboratory of the School of Health Sciences of the University of Aveiro (Lab3R-ESSUA) and at the Leiria Hospital Center. Inclusion criteria consisted of: being 18 years old and over, providing assistance to a relative/friend with a clinical diagnosis of COPD (according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria [1]), being able to understand the objectives and procedures of the study, and to voluntarily accept to participate. Caregivers were excluded if they or their family member/friend with COPD had a significant cardiorespiratory (in addition to the diagnosis of COPD for patients), neurological, cognitive or musculoskeletal impairment, that could cause additional burden to the caregiver, or if caregivers needed care themselves.

Patients with COPD were identified by the healthcare professionals working in the institutions where recruitment was conducted, after ensuring the fulfillment of the eligibility criteria. Patients were asked to provide the contact of their caregiver, after being informed about the study. Caregivers were then contacted by the researchers to provide additional information about the study and ask their willingness to participate. An appointment was scheduled with those agreeing to participate. Each participant signed the informed consent prior to data collection.

Procedures

Data collection consisted of a structured questionnaire about caregivers’ demographics (age, sex, academic qualifications, marital status, work status, relationship with the person receiving care), caregiving context (type and duration of care provided in hours per week and number of years), distress associated with caregiving burden (Informal Caregiver Burden Assessment Questionnaire (QASCI)) [13] and self-reported PA levels (Habitual Physical Activity Questionnaire (HPAQ)) [14]. Patients’ age, sex and lung function data were obtained from the patient's clinical record with the collaboration of the healthcare professionals from the participating institutions. Values of Forced expiratory volume in 1 s (FEV₁) percentage predicted were used to classify COPD severity according to the GOLD criteria [1].

Instruments

Informal caregiver burden assessment questionnaire (QASCI)

The QASCI is a Portuguese tool developed to evaluate the distress levels associated with caregiving burden [13,15]. Other caregiver burden instruments have been previously used in caregivers of patients with COPD; however, their measurement properties have been scarcely investigated in this population and the results were mostly indeterminate [16]. The QASCI has already been validated in caregivers of people with various chronic diseases, including respiratory diseases [13,15], presenting good validity, test-retest reliability and internal consistency (Cronbach's alpha = 0.90) results [15]. It has 32 items scored from 1 to 5 and consists of the following 7 subscales: Emotional Burden (4 items), Implications for Personal Life (11 items), Financial Overload (2 items), Reactions to Demands (5 items), Perception of Efficacy and Control Mechanisms (3 items), Family Support (2 items) and Satisfaction with the Role (5 items). For the final scores of each subscale to present homogeneous and comparable values, the minimum score of each subscale has to be subtracted from the sum of that subscale, then divided by the difference between the maximum and minimum score, and lastly multiplied by 100 [13]. Results are inverted (by subtracting the score to 100) in the subscales Satisfaction with the Role, Family Support, and Perception of the Efficacy and Control Mechanisms, so that higher scores correspond to higher levels of distress. The total score of the questionnaire is obtained by calculating the mean between the scores of all subscales. The level of caregivers’ distress can be assorted from the total score, ranging from 0 to 100 (overall score and each subscale score), and interpreted as: low (0-25), moderate (26-50), high (51-75) and extreme (≥76). To the best of the authors’ knowledge, there is only a Portuguese version of the scale.

Habitual physical activity questionnaire (HPAQ)

The HPAQ is an easy-to-use instrument that assesses self-report PA levels [14]. It consists of 8 items scored on a 5-point scale, except for the question regarding the practice of sports, in which the individual is asked to identify up to two sports practiced (if the individual practices more than two different sports, the sports practiced more regularly should be considered), and the frequency and duration of practice. The intensity of the sports identified by the individual is then determined according to the compendium of physical activities [17], based on energy expenditure in metabolic equivalents (METs). The HPAQ evaluates PA in 2 domains: PA-sport (questions 1, 2, 4 and 5) and PA-leisure (questions 3, 6, 7 and 8). The score from each domain is obtained by averaging the scores of the questions. The score in question 6 must be inverted to be included in the PA-leisure and Total scores. Both domain scores are added together to determine the Total PA score, with higher scores representing higher PA levels. The Portuguese version of the HPAQ presented good internal consistency in a population of adults living in the community, with a Cronbach's alpha for the Total PA of 0.78 [14].

Data analysis

Descriptive statistics were used to characterize the sample and to present the scores obtained in the QASCI and the HPAQ. The relationship between caregiving distress (total QASCI score and subscales) and caregivers’ self-reported PA (total HPAQ score) was assessed with Spearman (ρ) correlation coefficients (first aim of the study), due to the non-normality of the data. Normal distribution of the data was assessed using the Kolmogorov-Smirnov test. Correlations were interpreted as follows: 0-0.09 negligible correlation; 0.1-0.39 weak correlation; 0.4-0.69 moderate correlation; 0.7-0.89 strong correlation; 0.9-1 very strong correlation [18].

To explore whether self-reported PA could potentially predict the distress associated with caregiving burden (dependent variable - total QASCI score), a simple linear regression was used. Multiple linear regressions were also performed to account for possible covariates (i.e. caregivers’ (age, sex) and patients’ (age, sex, lung function) characteristics; caregiving duration in hours per week and years) using the Stepwise method.

Data were analyzed using the Statistical Package for Social Sciences (SPSS)® software version 23 (IBM, Armonk, New York, USA). Statistical significance was considered at p < 0.05.

Results

Participants

Sixty-three (n = 63) caregivers were contacted; from these, 4 refused to participate and 9 were not available at the time of data collection. Therefore, the final sample consisted of 50 informal caregivers of patients with COPD. Table 1 presents caregivers’ sociodemographic and caregiving information. Caregivers had a mean (±standard deviation (SD)) age of 62.7 ± 9.8 years old, mostly women (n = 44, 88%). Most caregivers were married (n = 38, 76%), had low educational qualifications (n = 28, 56% had only 4 years of education), and were retired (n = 27, 54%) or had a full-time paid employment (n = 15, 30%). Caregivers were predominantly spouses of patients with COPD (n = 39, 78%), cared for more than 4 years (n = 27, 54%) and for more than 40 h per week (n = 19, 38%).

Table 1. Caregivers’ characteristics (n = 50).

Characteristics	Caregivers (n = 50)
Age (years), Mean ± SD	62.7 ± 9.8
Sex, n (%)
Female	44 (88%)
Male	6 (12%)
Academic qualifications, n (%)
1^st cycle	28 (56%)
2^nd cycle	4 (8%)
3^rd cycle	3 (6%)
Secondary/ High School	7 (14%)
Undergraduate Course	3 (6%)
Higher Education	5 (10%)
Marital Status, n (%)
Single	2 (4%)
Married	38 (76%)
Divorced	3 (6%)
Widowed	2 (4%)
Common-law marriage	5 (10%)
Work Status, n (%)
Full-time Employment	15 (30%)
Domestic	4 (8%)
Retirement	27 (54%)
Unemployment	3 (6%)
Other	1 (2%)
Relationship with person cared for, n (%)
Spouse/ Partner	39 (78%)
Daughter/ Son	10 (20%)
Daughter/ Son in law	1 (2%)
Caregiving hours per week, n (%)
0-8h	13 (26%)
8-20h	8 (16%)
20-40h	10 (20%)
>40h	19 (38%)
Caregiving period (years), n (%)
Less than 1	5 (10%)
1-2	4 (8%)
2-4	14 (28%)
More than 4	27 (54%)
QASCI levels, n (%)
Low (0-25)	24 (48%)
Moderate (26-50)	19 (38%)
High (51-75)	7 (14%)

QASCI, Informal Caregiver Burden Assessment Questionnaire; SD, standard deviation.

Patients with COPD were mostly men (n = 40, 80%), with a mean (±SD) age of 70.5 ± 8.0 years old and a mean (±SD) FEV₁ of 45.2 ± 21.3% predicted (Table 2 ). More than half of the patients were in the severe (GOLD 3, n = 19, 38%) and very severe (GOLD 4, n = 16, 32%) stages of COPD (Table 2 ).

Table 2. Characteristics of patients with COPD (n = 50).

Characteristics	Patients (n = 50)
Age (years), Mean ± SD	70.5 ± 8
Sex, n (%)
Female	10 (20%)
Male	40 (80%)
GOLD Classification, n (%)
GOLD 1 - Mild	3 (6%)
GOLD 2 - Moderate	12 (24%)
GOLD 3 - Severe	19 (38%)
GOLD 4 - Very Severe	16 (32%)

GOLD, Global Initiative for Chronic Obstructive Lung Disease; SD, standard deviation.

Caregiver distress and physical activity

Table 3 presents data from the QASCI and HPAQ total scale and subscales. The median QASCI score was 25.9 (Q1–Q3: 12.7–44.8). Implications for Personal Life (median: 27.3, Q1–Q3: 6.8–47.7), Emotional Burden (median: 25, Q1-Q3: 0–45.3), Family Support (median: 25, Q1–Q3: 0–62.5) and Perception of Efficacy and Control Mechanisms (median: 25, Q1–Q3: 8.3–60.4) were the QASCI subscales with the highest median values. Regarding the levels of distress, 24 (48%) caregivers were in the low level, 19 (38%) in the moderate level and 7 (14%) in the high level of distress (Table 1).

Table 3. Total score and subscale scores of the Informal Caregiver Burden Assessment Questionnaire (QASCI) and the Habitual Physical Activity Questionnaire (HPAQ) (n = 50).

	Median (Q1–Q3)
QASCI total score	25.9 (12.7–44.8)
Emotional Burden	25.0 (0–45.3)
Implications for Personal Life	27.3 (6.8–47.7)
Financial Overload	18.8 (0–40.6)
Reactions to Demands	20.0 (5.0–36.3)
Perception of Efficacy and Control Mechanisms	25.0 (8.3–60.4)
Family Support	25.0 (0–62.5)
Satisfaction with the Role	20.0 (5.0–41.3)
HPAQ total score	4.8 (4.3–6.3)
PA-Sport	2.3 (2.0–3.3)
PA-Leisure	2.6 (2.3–3.0)

HPAQ, Habitual Physical Activity Questionnaire; QASCI, Informal Caregiver Burden Assessment Questionnaire; SD, standard deviation. Note: The results from the QASCI subscales Satisfaction with the Role, Family Support, and Perception of the Efficacy and Control Mechanisms were inverted so that higher scores correspond to higher levels of distress, as in the remaining questionnaire. In the HPAQ questionnaire, the 6th item was also inverted to be coherent with the remaining questionnaire.

The median HPAQ score was 4.8 (Q1–Q3: 4.3–6.3).

Correlations between caregiver distress and physical activity

There was a significant, negative and moderate correlation between caregiver distress (QASCI total score) and self-reported PA (HPAQ total score) (ρ=-0.46; p = 0.01).

Significant, negative and moderate correlations were also found between total self-reported PA and four QASCI subscales (Emotional Burden ρ=-0.47, Implications for Personal Life ρ=-0.52, Financial Overload ρ=-0.44, Perception of Efficacy and Control Mechanisms ρ=-0.42, all p < 0.01). A weak but significant and negative correlation was found with total self-reported PA and the QASCI subscale Family Support (ρ=-0.29, p < 0.05) (Table 4).

Table 4. Correlations between caregiver distress (QASCI) and physical activity (HPAQ) (n = 50).

	HPAQ total score (ρ)
QASCI total score	−0.46**
Emotional Burden	−0.47**
Implications for Personal Life	−0.52**
Financial Overload	−0.44**
Reactions to Demands	−0.22
Perception of Efficacy and Control Mechanisms	−0.42**
Family Support	−0.29*
Satisfaction with the Role	−0.22

HPAQ, Habitual Physical Activity Questionnaire; QASCI, Informal Caregiver Burden Assessment Questionnaire. Since data were not normally distributed, the Spearman’s rank correlation coefficient (ρ) was used.

* p < 0.05.

** p < 0.01.

Potential predictors of caregiver distress

The HPAQ total score alone predicted 23% of the QASCI total score (B1=-7.561, β=-0.477) (p = 0.001; r²=0.23). When accounting for possible covariables, the variables included in the equation were the HPAQ total score (B1=-6.838; β=-0.417) and caregiving hours per week (B2 = 5.642, β = 0.345) (p < 0.001; r²=0.34), predicting 34% of the QASCI total score.

Discussion

This study aimed to assess the relationship between the distress associated with caregiving burden and PA in informal caregivers of patients with COPD. A moderate negative correlation was found between distress and self-reported PA, suggesting that caregivers with higher levels of distress present lower levels of PA. This finding is in line with the hypothesis proposed in this study. Self-reported PA seems to be a significant predictor of caregiver distress, explaining 23% of its variance alone and 34% when combined with the number of caregiving hours per week.

Half of the informal caregivers participating in the study (n = 26, 52%) were in the moderate or high levels of distress. The Implications for Personal Life, Emotional Burden, Family Support and Perception of Efficacy and Control Mechanisms were the dimensions which mostly contributed to caregivers’ distress. These subscales are related to the level of support received by the family in the care provided to the patient, the caregiver’s perception of their ability and knowledge to provide care to the patient, and the impact of the caregiving role on their lives. Studies conducted in COPD have highlighted the importance of caregivers relying on their knowledge to provide care to their family member [6,7], and the value of family support in this complex task [2,6,7]. A study conducted on caregivers of patients with advanced COPD reinforced the need to provide caregivers with knowledge and strategies to support the patient, and to manage their caregiving role and the associated feelings of helplessness and powerlessness [19]. Furthermore, previous research has shown that caring for an individual with COPD affects several dimensions of caregivers’ lives, including physical health, emotional, social, relational and financial/employment life dimensions [20]. The present findings, along with previous literature, suggest that caregiving distress should be routinely assessed in clinical practice to identify caregivers who may benefit from interventions targeted at reducing distress.

Caregiver distress was significantly related to caregivers’ self-reported PA levels, and HPAQ was able to explain the variance of the QASCI total score in 23%. This means that self-report PA alone may have a significant impact on the distress levels associated with caregiving burden. Findings on the relationship between caregiver distress and self-reported PA were similar to those observed in other caregiver populations [21]. Physiologically, PA activates the hypophysis-pituitary-adrenal axis which, when continuously activated, reduces the response of the neuroendocrine system reducing cortisol levels according to the intensity of PA [22]. This happens even with short bouts of PA [22].

When considering the QASCI subscales, it was found that reduced self-reported PA levels were mostly related to higher emotional burden and financial overload, lack of family support, negative implications for personal life, and a lower perception of efficacy and control mechanisms. Family support has been mentioned as a PA enabler in patients with COPD [23]. Considering that PA levels of patient-caregiver dyads seem to be correlated [24], interventions aimed at enhancing both caregivers’ and patients’ PA levels may be promising to help them adopt healthy lifestyles together and improve their health status. However, it is important to highlight that this type of interventions may not be enough to counteract the physical inactivity observed in both populations, as PA is a complex behavior influenced by an interplay of individual, social and environmental factors [25]. For example, some of the barriers for the adoption of PA behaviors observed in the general population are the lack of free time for PA and the feeling that it disrupts their daily routine [26]. Caregivers, with the added tasks inherent to their role, may also experience this difficulty. Thus, a comprehensive assessment of the barriers and enablers of PA behavior in caregivers of patients with COPD may be necessary to define the best strategies for PA promotion in this population.

When caregiving duration in hours per week was added to the HPAQ in the linear regression model, the equation predicted 34% of the variance in caregiver distress. This finding suggests that the duration of caregiving may also have an important role on the distress levels of informal caregivers, with more hours of caregiving per week potentially leading to bigger distress levels. This is in line with previous research which has shown that the duration and amount of care provided have an impact on the physical and mental health of the caregiver [3,8]. The levels of PA presented an inverse relationship with distress levels, with higher levels of self-reported PA being related to lower levels of distress in this specific population of informal caregivers of patients with COPD. Although it is not yet possible to establish a causal relationship between these variables, the present findings suggest that interventions aimed at reducing caregivers’ distress levels may not only include a reduction in the number of hours of care (e.g. respite care [6]), or psychoeducational interventions to help caregivers dealing with their role, but also PA-enhancing interventions especially targeted to those who present low levels of PA [7,27].

Limitations

Some limitations need to be acknowledged. Most caregivers were female, more than half of them were providing care for more than 4 years, and patients were mostly in the severe and very severe COPD grades, which may reduce the external validity and generalization of the findings. Studies with a larger and more balanced sample should be conducted to analyze the extent of these findings. The HPAQ was used to assess caregivers’ PA. As a self-report questionnaire, this tool relies on individuals’ memory and may be influenced by several variables such as the design of the questionnaire, cultural factors or social desirability [28]. Therefore, future research should consider using objective measures to assess PA. The limited nature of cross-sectional studies precludes definitive inferences about the causal relationship between caregivers’ PA and distress levels. Longitudinal studies assessing changes in these variables could be useful to better understand their relationship in this population. It was not possible to assess the potential influence of patients’ health status (e.g. COPD Assessment Test [29]), symptoms and exacerbation history (e.g. ABCD assessment tool [1]) on the relationship between caregiver distress and PA, although they may impact on the caregiving experience [2,30]. Future research should also explore this association.

Conclusions

This study showed that higher levels of self-reported PA may be related to decreased levels of distress associated with caregiving burden in caregivers of patients with COPD. Further research is needed to understand this causal relationship.

Declaration of interest

The authors report no conflict of interest.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI-01-0145-FEDER-028446), and by national funds (OE) through Fundação para a Ciência e Tecnologia (FCT/MCTES) (PTDC/SAU-SER/28446/2017), within the project “OnTRACK – On Time to Rethink Activity Knowledge: a personalized mHealth coaching platform to tackle physical inactivity in COPD”, and by Portuguese national funds provided by FCT (UIDB/05704/2020).