Functional Status of Patients on Maintenance Haemodialysis and Burden of Their Caregivers: An Example from a Tertiary Referenz Hospital in Cameroon

Background: Patients on maintenance hemodialysis (MHD) often depend on caregivers due functional status impairment (FSI). We evaluated the functional status of patients on MHD and the burden on their caregivers in Douala


Introduction
Chronic kidney disease (CKD) is a major public health problem and progresses to kidney failure (KF) [1,2]. Patients with KF require kidney replacement therapy (KRT) of which maintenance hemodialysis (MHD) is the main modality used in the world [3]. Hemodialysis (HD) reduces significantly the death of patients with KF but results in significant lifestyle changes [4]: reduces the patient's energy level; affects their ability to work and perform everyday activities with the frequent need to be hospitalized; disrupts the normal lives of patients and their caregivers [5]. This is due to a decrease in the patient's functional status (ability of the patient to perform essential activities for independent living) [6][7][8][9]. Also, carrying for a patient on MHD is stressful and can affect the physical and psychological well-being of the caregiver [10]. Caregivers are the people most involved in the care of patients in helping them adapt and manage their disease [4,[11][12][13][14]. Therefore, it appeared that both, the patient and caregiver are affected by the effects of a disease's treatment.

Study setting
This was a cross-sectional study from February to May 2021 (3 months), carried out at the nephrology-HD unit of the Douala General Hospital (DGH), one of the main tertiary referral hospitals in Cameroon. The DGH haemodialysis unit is the unique public center founded by the government in the littoral region of the country and it serves the needs of the majority of patients with KF. An average of 220 chronic patients is registered. This study was approved by the Ethics Committee of the Faculty of Medicine of the Douala University Cameroon number 2534 CEI-UDo/06/2021/T and participants provided a written consent.

Study participants and data collection
All consenting adult patients 18 years or more who had been on HD for at least 3 months and their caregivers were included in the study. Socio-demographic data of participants were recorded (sex, age, occupation, marital status, educational level, monthly income and the caregiver's relationship with the patient). Clinical data on the patients that was collected were: comorbidities (hypertension, diabetes mellitus, history of stroke, HIV, viral hepatitis (B and C), baseline nephropathy and dialysis parameters (dry weight, height, body mass index and blood pressure).
For each patient, functional status was assessed by the Global Functional Status Scale combining the 5 activities of daily living (ADL) with each scored from 0 to 1 for a total of 13 points [9]. Functional status impairment was considered as moderate for a score between 1 to 5/13 and severe for a score >5/13 [9]. Caregiver (people most involved in the care of patients and helping them adapt and manage their disease) burden was assessed by the Zarit scale consisting of 22 questions with each scored from 0 to 4 for a total of 88 points [22]. A score between 0 and 20 points corresponded to little or no burden, a score between 21 and 40 corresponded to a mild to moderate burden and a score of above >40 was considered as severe [22].

Data analysis
Statistical analyses were performed using SPSS statistical software v.25 for Windows. Categorical variables were reported as frequency and percentages in which comparisons were performed using Chisquare test or Fisher's exact test when appropriated. Continuous variables were summarized using means (with standard deviations), and medians where necessary. Independent variables associated with functional status impairment and high caregiver burden were analysed by multiple logistic regression. A p-value less than 0.05 were considered statistically significant.

General characteristics of study population
A total of 184 patients were included, with males accounting for 65.22 % (120/184), and the mean age (SD) was 47. 29

Factors associated with FSI
In multivariate analysis, factors associated with FSI were: age ≥ 50 years, patient and caregiver monthly income <35.000 XAF (53.5 euro, 60.52 USD), presence of diabetes, dialysis duration ≥ 15 years and a child as the caregiver (Table 2).

Factors associated with caregiver burden and the relationship between FSI and caregiver burden on multivariate analysis
Factors associated with caregiver burden and the relationship between FSI and caregiver burden were: male patient, patient's age ≥ 70 years, patient's monthly income <35000, inability to do shopping and laundry, caregiver's age ≥ 50 years, and the caregiver being a student (Table 3). There was a relationship between patient's FSI and caregiver burden (p-value <0.001), in fact the patient's FSI increased the risk to caregivers to develop a burden by 3.87 times (Table 4).

Discussion
The aim of this study was to evaluate the FSI of patients on MHD and the burden to their caregivers at the DGH. The prevalence of FSI in this study was 69.02 % (127/184) and the caregiver burden was 87.5 % (161/184). Age, diabetes, dialysis vintage, monthly outcome and the relationship with caregiver were factors affecting either FSI or caregivers burden.
FSI is highly prevalent in the dialysis population, with a range of 32 to 95% [8,9,15,[23][24][25][26][27][28] [8,24,28]. This high prevalence could be explained by the chronic nature of KF, multiple comorbidities, physical inactivity, anaemia, persistent uraemia, and the repeated need for hospitalization [25]. Our prevalence is lower than the 95% of Cook et al. in Canada [28] probably due to the aging Canadian population (75 vs 47.29 years). Our results were high from those of Akash N, et al. in Jordan and Ifudu O, et al. in the United States, who found a prevalence of 32% and 38.8%, respectively [23,25]. This difference could be explained by the fact that compared to our study population their patients had a longer duration on dialysis and also had 3 dialysis sessions per week, which is known to improve the quality of life in patients.
The prevalence of caregiver burden was 87.5%, which is close to the results of Adejumo OA, et al. in Nigeria who reported a prevalence of 82.7% [13]. This prevalence could be explained by the combination of physical labour, emotional pressure, social restrictions and economic demands by the caregivers. Our prevalence was however higher than the 23% found by Goto NA, et al in the caregivers of patients initiating dialysis in the Netherlands [9]. The difference in care organization with the use of social workers in developed countries did not compare to our setting where the care depends more on family members [9].
Factors associated with FSI were: patient's age ≥ 50 years, patient and caregiver monthly income <35000, presence of diabetes, longer duration on dialysis ≥ 15 years and being accompanied by a child. Older age and diabetes were also reported by Carlson [23,25,26]. The dialysis population is increasingly aging and has an increased risk of physical deterioration that affects their mobility and ability to care for themselves [25]. Diabetes is responsible of many micro and macrovascular complications that can lead to an alteration of the functional status of affected patients [29]. Monthly incomes <35000 of patients and their caregivers were also associated to FSI. This could be explained by the fact that in our context, despite the state subsidy for dialysis sessions, the out of pocket payment for dialysis care in   Cameroon is very high and commonly out of reach for most patients [30], increasing the burden on patients and family.
Factors associated with caregiver burden were: male patient, patient's age ≥ 70 years, patient's monthly income <35000, inability to do shopping and laundry, caregiver's age ≥ 50 years, and the caregiver being a student. Caregiver's age ≥ 50 years and male gender was also reported by Zhang et al. in China [31]. Middle-aged caregivers and men are generally more concerned about missed work days, work interruptions, and decreased productivity due to care giving. Low monthly income was also associated with caregiver burden in this study and implies that the high cost of care is difficult to access [31]. Mashayekhi F, et al. in Iran and Zhang R, et al. in China also reported similar results [11,31].
Caregivers of patients who require greater assistance with daily living experience greater a greater burden [32]. In our study, we found that functional dependence increases the caregiver burden by 3.87 times. Providing long-term daily care to patients on MHD leads to physical and psychological exhaustion which increases with the level of dependency of these patients [32]. Caregivers feel less responsible and burdened if monthly income is high and if patients are independent in their daily activities and complain less about their dialysis treatment.

Conclusion
In this study two out of three patients had a FSI and seven out of eight caregivers had a burden. A patient with FSI increased the odds of the caregiver's burden. It is therefore necessary to identified patient with FSI systemically and to provide psychosocial support to their caregivers with the aim to reduce the burden associated with the disease.