The Quality of Life of Caregivers of People with Type 2 Diabetes Estimated Using the WHOQOL-BREF Questionnaire

: Type 2 diabetes (T2D) poses a growing global health challenge, impacting patients’ and their caregivers’ well-being. This study investigates the inﬂuence of T2D complications on caregivers’ quality of life (QoL) using the WHOQOL-BREF questionnaire, accounting for factors like age, disease duration, and control. The research involved 382 T2D patients and 300 caregivers from Vuk Vrho-vac University Clinic for Diabetes, Endocrinology, and Metabolic Diseases. The WHOQOL-BREF questionnaire assessed caregivers’ QoL across physical, psychological, social, and environmental domains. Complications, including retinopathy, neuropathy, and kidney disease, were examined for their effects on QoL. Patients’ age impact, gender differences, and disease duration were analyzed. T2D complications had varying impacts on different QoL domains. Caregivers of patients with multiple complications showed signiﬁcant social functioning impairment. Those without complications reported lower psychological health. Age correlated with poorer physical health scores. Female caregivers rated higher in psychological and environmental health. Disease duration and T2D control had no signiﬁcant impact on caregiver QoL. Caregivers’ concerns included medication adherence and worry about their partner’s health. This study illustrates the delicate interplay between T2D patients and caregivers, highlighting the multifaceted effects of chronic illness. Comprehensive healthcare techniques that address emotional and social components in addition to medical care are critical for improving the well-being of both patients and their caregivers. The ﬁndings contribute to a broader understanding of T2D care dynamics, advocating for empathetic and all-encompassing healthcare practices.


Introduction
Type 2 diabetes (T2D) is a complex metabolic condition characterized by an interplay of genetic and environmental factors.According to the International Diabetes Federation (IDF), 537 million individuals over the age of 18 have diabetes in 2021, with a predicted increase to 643 million by 2030.The number of patients with T2D is increasing in all parts of the world, and it is increasing the fastest in poorly or moderately developed countries with a lower national income.Diabetes is the main cause of blindness, end-stage renal disease, stroke, heart attack, and lower limb amputations [1].Quality of life (QoL) has emerged as a prominent concept and research focus in the domains of health and medicine [2].There is no universal definition of the term, however, the World Health Organization (WHO) defines QoL as: "An individual's perception of their position in life in the context of the culture in which they live and concerning their goals, expectations, standards, and concerns" [3,4].Furthermore, the WHO developed the WHOQOL-BREF questionnaire, which is a condensed version of the WHOQOL-100 questionnaire, and is a widely used method for assessing an individual's overall quality of life.The abbreviation "BREF" refers to "Brief Version", suggesting that it contains fewer questions than the lengthier version.The questionnaire is intended to provide a thorough picture of a person's wellbeing and general quality of life.It is divided into four major domains, each reflecting a critical part of life's happiness and functioning.The physical domain examines a person's perception of their physical health, which includes characteristics such as energy level, pain, discomfort, sleep, mobility, and daily activities.The psychological domain investigates psychological well-being, such as sentiments of optimism, self-esteem, body image, and overall life satisfaction.The social domain assesses an individual's social connections, such as friendship and family support, personal relationships, and ability to participate in social activities.In contrast, the environmental domain is concerned with a person's contentment with their living conditions, access to health care, financial security, safety, and the entire environment in which they live.The WHOQOL-BREF questionnaire normally has 26 items covering the four aforementioned domains.In addition to these questions, there are two general questions about a person's overall quality of life and health.Individuals rate their level of agreement, contentment, or frequency of experiences on a Likert scale while responding to inquiries.The questionnaire is intended to be flexible to various cultural and linguistic situations, making it appropriate for usage in various countries and populations.It has been widely used in clinical and research contexts to assess the impact of health issues, therapies, and other factors on a person's quality of life.Social support given by immediate family, partners, or spouses has shown positive effects in patients with cardiac disease or cancer [5].The psychological state of spouses has been shown to play a role in their ability to provide support and affect the physical HRQOL in patients with prostate cancer [6,7].Several prior studies have evaluated caregiver QoL in different contexts and are discussed later, however, none have evaluated the effects of specific T2D complications on caregiver QoL.Considering the role of social support in the QoL of patients with T2D, an investigation of factors affecting it may be necessary for creating new approaches in the overall treatment of T2D and improving the QoL of these patients.
In this study, we aimed to determine the effect of T2D complications on the different aspects of the caregiver's QoL as determined by the WHOQOL-BREF questionnaire.Additionally, we aimed to investigate other additional factors that may contribute to decreased QoL, primarily age and disease duration.

Setting and Study Protocol
The study was designed as a quantitative study using the WHOQOL-BREF questionnaire and available medical data.The research was conducted at the "Vuk Vrhovac" University Clinic for Diabetes, Endocrinology, and Metabolic Diseases at Merkur Clinical Hospital from June 2019 to March 2020.This study was part of a doctoral thesis that involved researching the quality of life of patients with T2D, their caregivers, and the opinions of medical staff involved in the care of T2D patients.Caregivers were defined as persons sharing the household with the patient, regardless of relationship or marital status, who take care of the patient and are responsible for helping the patient adhere to treatment.The first part of the study involved T2D patients completing the WHOQOL-BREF questionnaire, followed by mailed questionnaires to partners.For patients whose caregivers came to their scheduled hospital visit, the questionnaire was given during the visit.Patients with T2D treated at the Clinic were included in the study.The study protocol planned the inclusion of 77 participants in each group classified by the comorbidity present.The number was determined based on an earlier pilot study investigating patient QoL, with standard power (80%) and significance (5%).The caregivers were separated into groups based on the comorbidity of the patient, namely: diabetic retinopathy, symptomatic diabetic polyneuropathy, patients with diabetic kidney disease (DKD) stage 4 or 5, second-and third-degree diabetic foot ulcers according to the Texas classification or with amputated extremities.For some patients, several comorbidities were expected and those patients were classified in the multiple complications group, and one group involved patients with T2D without complications.After completion of their questionnaires, patients were given caregiver questionnaires with stamped envelopes containing a letter of invitation to the study, informed consent, and the questionnaire form.All questionnaires were coded to enable pairing of the patient and caregiver questionnaires.Patients without T2D complications and their caregivers were used as the control group.Single or widowed patients or those without caregivers were included in the patient analysis, however, they were not given caregiver questionnaires.

Tools and Data Acquisition
The questionnaire used was the WHOQOL-BREF designed by the World Health Organization (WHO), which was translated into Croatian and validated in earlier research by Pibernik Okanović [8].Written permission was obtained from the author for the use of the questionnaire.The questionnaire contains 26 original questions grouped into four domains: physical health (7 items), psychological health (6 items), social relationships (3 items), and environmental health.Each question in the WHOQOL-BREF is rated on a Likert scale, ranging from 1 (very dissatisfied/very poor) to 5 (very satisfied/very good).The scores for each domain are transformed into a linear scale from 0 to 100 [9].Higher scores in a domain indicate a better quality of life in that specific area.Several additional questions on T2D were added to the patient questionnaire, specifically our added questions about the time of T2D diagnosis, complications of the disease, complication onset, and whether the complication ever required hospital admission.At the end of the questionnaire, we added questions that evaluated the patient's adherence to the instructions they received from the nurses and why (we offered several answers) they did so.We also offered potential explanations for not following the instructions.In question 39, we also asked them to rate the information they received from doctors and nurses on a scale from 1 to 10, where a rating of 1 means that they did not receive any information, and a rating of 10 means that they received all the necessary information.In question 40, we asked them what they would carry out to prevent chronic complications if they had all the necessary information about them.In question 41, we wanted to obtain patients' recommendations on what they now consider important in the care of people with diabetes.In the end, we provided a space for additional text if patients would like to write something else about the care of people with diabetes.
In the first three questions of the caregiver questionnaire, we asked for information on gender, age, and education.Questions 4 to 29 were questions from the WHOQOL-BREF questionnaire.We supplemented the original questionnaire with questions regarding the perceived burdens to caregivers related to the illness of their partners.The last added question was meant to investigate the opinions of caregivers and their recommendations about taking care of people with T2D.
Additionally, medical record data regarding complications of the disease and disease management, including laboratory results, were collected for each patient on a predetermined form.

Statistical Analysis
Numerical values were presented with average and standard deviation or median and interquartile ranges (IQR), where appropriate.Categorical values were presented as absolute values and proportions (%).The normality of data distribution was analyzed using the Shapiro-Wilk test.For the comparison of numerical data, the Mann-Whitney test was used, for the analysis of several groups the Kruskal-Wallis test was applied, and, where appropriate, for multiple comparisons, Dunn's post hoc test with Bonferroni correction was performed.For categorical variables, we used the Chi-squared test, with Yates correction where appropriate.For the determination of the correlation of numerical variables, the Spearman rank correlation test was used.Data distribution was presented in graphical and tabular form.Data were presented in tables and text.
The primary goal of this study was to evaluate the QoL of caregivers of patients with T2D and its complications.The secondary goals were to evaluate the correlation of patient age, disease duration, T2D regulation, and the presence of comorbidities on the partner's QoL.

Patient Characteristics
For participation in the study, 434 people with T2D were invited, 382 (84.9%) of whom signed informed consent and submitted a completed questionnaire.Of the 52 respondents who were not included in the research, 8 of them refused to participate, and 44 did not return the completed questionnaire.Overall, 382 patients were included in the study.The majority of participants were female (67.3%) and younger than 60 years of age (57%).Demographic data are presented in Table 1.One-fifth (20.2%) of the included patients had no complications of the disease, a third (33.5%) had several complications, 9.9% had isolated DKD, 15.7% had isolated diabetic neuropathy, 10.2% had an isolated diabetic foot ulcer, and 10.5% had isolated diabetic retinopathy.
In patients with disease complications, 34 had the first occurrence in the past year, 82 within 1-5 years, 68 6-10 years ago, and 121 more than 10 years ago.T2D complications necessitated up to two hospital admissions in 82 patients, three-four in 68 patients, five-six in 62 patients, and more than seven in 59 patients.

Caregiver Characteristics
A total of 344 caregivers of people with T2D were invited to participate in the research, 44 of which did not return a completed questionnaire, and for the remaining 300 partners and/or close family members, the survey was conducted during the visit, delivered by mail or brought by patients to the next check-up (87.2%).Most caregivers were female (67%), aged 51-70 (56%), and had a high school level education (55%).More detailed data are presented in Table 2. Analyzing the answers of the caregivers in which they stated what burdens them in connection with the illness of their partner/family member, they were able to choose several answers.A total of 88 (29.3%) of them stated that they were burdened by the care of medication taking and 84 (28.0%) by the diet.A total of 56 (18.7%) of them worried about frequent check-ups and 94 (31.3%) about their partner not following the advice they received.Uncertainty regarding a family member falling seriously ill burdens 185 (61.7%) partners and financial problems 49 (16.3%) of them.A total of 136 (45.3%) of them worry about who will take care of the sick respondent if they become seriously ill and transportation burdens 31 (10.3%)caregivers.
The caregivers were asked to recommend or suggest what should be carried out regarding the care of people with diabetes, so 102 of them (34.0%)recommended more frequent check-ups, 108 (36%) advised hospital stay during the work-up and treatment of complications, 165 (55.0%) of them believe that all patients must attend educational classes, and 158 (52.7%) caregivers pointed out that chronic complications should be taught about at the beginning of the disease, while 215 (71.7%) believe that patients should have mandatory check-ups to detect complications as early as possible.A total of 76 (25.3%) caregivers believe that all patients should be educated in the day hospital, 101 (33.7%) suggest that there should be programs and tests on everything patients need to know regarding their illness, and 106 (35.3%) believe that a psychologist should be included in the treatment process.

Quality of Life of Caregivers of Individuals with Type 2 Diabetes
A further analysis of the correlation between T2D complications and their effects on the caregivers' quality of life was performed.
Table 3 presents a comprehensive comparison of caregiver groups based on the presence or absence of specific T2D complications and their corresponding dimensions of caregiving burden, including physical functioning, psychological functioning, social functioning, and environmental health.Our analysis revealed statistically significant differences among the caregiver groups.Specifically, we found a significant difference in social functioning (Kruskal-Wallis test, p = 0.017), indicating that this dimension varied significantly across caregiver groups based on the presence of complications.However, to provide a clearer understanding of these differences, we conducted post hoc multiple comparison tests.Upon closer examination, caregivers of patients with several complications reported significantly more impaired social functioning compared to caregivers of patients without T2D complications (post hoc multiple comparisons test, p = 0.022).This suggests that caregivers of patients facing multiple complications may experience a greater challenge in the social functioning dimension of caregiving compared to those without T2D complications.Additionally, it is worth noting that caregivers' perceptions of various dimensions varied across different complication types.For instance, caregivers of patients with diabetic retinopathy consistently rated social functioning as the lowest among all dimensions, while caregivers of patients without T2D complications gave the lowest rating to psychological health.Conversely, environmental health received the highest ratings from caregivers of patients with diabetic neuropathy and DKD and those without T2D complications.

Discussion
Our study involved 300 caregivers of patients with T2D with or without complications of the disease.The results indicate a decreased QoL in different domains in caregivers of T2D patients, particularly in those with multiple complications.The QoL domain most affected is social health, which was rated the lowest by all patients with complications, while caregivers of patients without disease complications rated psychological health the lowest.The older age of patients was associated with worse scores in physical health.Interestingly, disease duration and current T2D control have shown no associations with the caregivers' QoL.The psychological and environmental health domains were rated higher in caregivers of female patients, probably indicating gender differences in coping.These results are consistent with the study by Hooker et al. focusing on spouse caregivers for patients with Alzheimer's disease (AD) and Parkinson's disease (PD), which found that wives caring for AD patients reported significantly worse mental health outcomes than husbands.This evidence suggests that gender differences can significantly impact the caregiving experience.Therefore, it is plausible that the gender-based disparities we observed in psychological and environmental health domains may be influenced by distinct coping strategies among caregivers of female patients.These findings highlight the importance of recognizing and addressing gender-related factors in caregiving support and interventions [10].
A Sudanese study carried out by Awadalla et al. examined the QoL of the caregivers of patients with type 1 and type 2 diabetes by using the WHOQOL BREF questionnaire [11].Overall, caregivers of patients with type 1 diabetes had lower scores than T2D caregivers and the general population, while the caregivers of patients with T2D had similar scores in all categories as the general population.Furthermore, in that study, the patient's age and duration of illness were positively associated with caregiver QoL domain scores.However, this study did not evaluate disease severity or the presence of complications of diabetes.In another similar Mexican study that used a different questionnaire, the domains of social and physical functioning were the highest rated [12].Additionally, the study demonstrated that increased caregiver overload was associated with decreased caregiver QoL.In a study of a large sample of US caregivers by Secinti et al., caregivers of patients of all chronic diseases reported worse mental health when compared to a population of non-caregivers.Studies investigating the effects of complications of T2D on the caregivers' QoL are few.A Turkish study evaluated the QoL of caregivers of patients with diabetic foot ulcers by comparing them to the QoL of caregivers of psychotic patients and patients with an inguinal hernia [13].Caregiver burden level was similar for both psychotic and diabetic foot ulcer patients and significantly higher than for hernia patients.The depression and anxiety scales of the diabetic foot ulcer group were significantly high and some points of the quality of life scales were determined to be significantly low.A correlation between the duration of caregiving and the burden was determined in the diabetic foot ulcer group.QoL was assessed using the SF-36 questionnaire, and caregivers of patients with diabetic foot ulcers scored lower than the other two groups for the domains of physical difficulties, vitality, emotional difficulties, and mental health.Notably, the number of participants in this study was low.Portuguese researchers investigated caregiver QoL over 10 months after amputation due to a diabetic foot ulcer and have found that the mean score of caregiving stress and mental and physical quality of life decreased over time [14].Providing support to caregivers, particularly during periods of increased burden and stress, may be important to improve the overall physical and mental health of the caregiver, which may indirectly improve the patient's QoL.Other factors that may influence QoL in the mental health domain of caregivers of diabetic foot amputees are the practice of physical activity, lower caregiver burden, better functionality in the family, and a lower number of reported traumatic symptoms.Better physical QoL was associated with a lack of other chronic diseases and fewer reported physical symptoms [15].The involvement of family and caregivers and its effect on the patient's QoL was indirectly shown in a study by Ebrahimi et al., where an educational program about diabetes resulted in larger increases in the patient's QoL when attended by family members and caregivers rather than by patients alone [16].
The study's main advantages are that it investigates the effects of T2D complications and provides a comprehensive understanding of how being a caregiver of someone with T2D affects various domains of QoL, such as physical health, psychological well-being, social relationships, and environmental factors.Understanding the partners' QoL could also help healthcare practitioners understand the stressors and obstacles that caregivers encounter.This can result in more customized interventions and better healthcare services.The study has the potential to raise awareness about the emotional and psychological toll that caring for someone with T2D may have on spouses.This could lead to more public awareness and support for caregivers.
On the other hand, the drawbacks of this study include the lack of examination of additional caregiver characteristics that may have influenced their QoL.Furthermore, the data acquired through the WHOQOL-BREF questionnaire are based on self-reported responses, which can be influenced by individual biases, emotions, and perceptions, potentially leading to mistakes in the results.Additionally, while the study may uncover connections between caregiving and quality of life, it may not establish causality.Other factors, such as pre-existing well-being or personal circumstances, may influence partners' quality of life.Additionally, the study did not include the financial and economic status of the patient and their caregiver, which may confound the results.Another limitation is possible selection bias.Partners who agreed to participate may have different features or experiences than those who declined, thus resulting in potential bias and affecting the generalizability of the findings.The study was limited by not reaching the planned number of participants.The study was abrupted in March 2020, at the onset of the COVID-19 pandemic, and was not continued as the pandemic has altered all aspects of everyday life and was considered a confounder to QoL measurement.
By addressing the specific issues of partners, healthcare practitioners can aim to improve the overall quality of life for this essential group within the diabetic ecosystem.Nonetheless, further research is needed to have a better knowledge of the individual aspects influencing partners' quality of life and to design tailored therapies that address their unique needs.Longitudinal studies could provide insights into the changing nature of partners' experiences over time, as well as the potential usefulness of various support interventions.

Conclusions
In conclusion, this study has shed light on the intricate relationship between T2D and the QoL of caregivers, primarily partners, who play a crucial role in supporting individuals with this condition.The research has unveiled several significant findings.Caregivers of individuals with T2D, particularly those with multiple complications, experience a notable decrease in their QoL.The domain most affected is social health, indicating the challenges faced by caregivers in maintaining their social connections and support networks.Furthermore, older caregivers tend to report lower physical health scores, suggesting that age may play a role in the physical strain experienced by caregivers.However, age does not significantly impact other domains of QoL.Next, female caregivers of T2D patients tend to rate their psychological and environmental health domains more positively.This may reflect gender-specific coping strategies and lifestyle changes adopted by female caregivers, which influence their perception of QoL.Surprisingly, neither the duration of the disease nor the current regulation of T2D in patients had significant associations with caregivers' QoL in this study.However, the burden on caregivers is influenced by factors such as medication management, diet, adherence to medical advice, financial concerns, and the fear of the patient's condition worsening.Providing support and resources for caregivers during these challenging times may contribute to improved overall QoL.Finally, caregivers emphasize the importance of regular check-ups, patient education programs, and early awareness of chronic complications as essential components of effective T2D management.The inclusion of psychologists in the treatment process is also suggested.
These findings underscore the critical role of caregivers in the lives of individuals with T2D and highlight the need for tailored support and interventions to enhance their QoL.Addressing the emotional and psychological aspects of caregiving, as well as providing practical resources and education, can significantly improve the well-being of caregivers.Furthermore, this research contributes to a broader understanding of the complexities of T2D management and its impact on the entire ecosystem surrounding the patient.While this study provides valuable insights, further research is warranted to explore the nuanced factors influencing caregivers' QoL comprehensively.Longitudinal studies and a more extensive exploration of additional caregiver characteristics could offer a deeper understanding of their unique experiences and needs.Ultimately, these efforts can lead to more effective support systems and improved healthcare services for individuals with T2D and their caregivers.

Table 1 .
Demographic characteristics of individuals with T2D.

Table 2 .
Demographic characteristics of caregivers of individuals with T2D.

Table 3 .
Quality of life of caregivers of individuals with T2D based on the presence or absence of specific chronic complications (n = 300).

Table 4 .
Association of functioning domains with the duration of T2D.

Table 5 .
Relationship between HbA1c and quality of life of partners, and correlation coefficients for individual components (n = 300).