Biosocial and disease conditions affecting the quality of life among older adults in Eastern Nepal

The ageing population in most low-and middle-income countries is accompanied by an increased risk of non-communicable diseases culminating in a poor quality of life. However, the factors accelerating this poor quality of life (QOL) have not been fully examined. Therefore, this study examined the factors influencing the quality of life of Nepali older adults. Data from a previous cross-sectional study, conducted between January and April 2018 in eastern Nepal, was used. The analytical sample included 794 older adults aged ≥60 years, selected by a multi-stage cluster sampling approach. QOL was measured using the Older People’s Quality of Life tool; dichotomized as poor and good QOL. Other measures used included age, gender, ethnicity, religion, marital status, physical activity and chronic diseases such as osteoarthritis, cardiovascular disease, diabetes, chronic obstructive pulmonary disease (COPD), and depression. The factors associated with quality of life were examined using mixed-effects logistic regression.

with a higher odds ratio of good quality of life.

Conclusion
The findings of this study echo the need to develop and implement policies aimed at improving the socio-cultural and disease conditions that catalyse poor quality of life in this population.

Background
Globally, the population of older adults aged above 60 years has seen an increase from 15% in 2015 to an estimated prevalence of 22% in 2015. The majority of these older populations currently live in low-and middle-income countries (LMICs) [1]. The demographic transition is evident in Nepal [2,3], a South Asian Country between India and China. In 2011, approximately 2.5 million of the Nepalese population were 60 years and older [2]. The growth rate of the older population, at 3.5%, has exceeded the growth rate of the general population at 1.35% [4].
Global aging has created a significant public health challenge for many countries, specifically LMICs, with scarce resources to address the social and health needs of its burgeoning population [1,5]. Generally, older adults are at a higher risk of developing non-communicable diseases, including cardiovascular diseases, diabetes, chronic kidney diseases, and mental health disorders [6,7]. This also has implications for the functional capacity of the individuals culminating in deleterious consequences for the general wellbeing and QOL of this population [8,9].According to the World Health Organization (WHO), QOL is the perceived position of an individual in the context of their value system and culture. It is also related to the goals, expectations, standards, and concerns of the individual's life [10]. Moreover, QOL is the result of the effect of physical, functional, social, and emotional factors that lead to individuals' wellness [11]. QOL has become an important outcome for many public health programs [12]. With an increase in the aging population, maintaining QOL of this elderly population has become an important challenge [13].
As a signatory of the sustainable development goals (SDG) for the 2030 agenda, the government of Nepal has formulated a national policy on ageing and recently "National Health Policy 2017" to address the needs of the Nepali older population. However, the implementations of the policy are limited to few programs such as "Old-Age-Allowance," "Jeshtha Nagarik Swashthopachar Kosh (Senior Citizens Health Facilities Fund)" and free "Health Care Service Program." However, the availability and quality of those services are questionable. Many older adults, especially in rural areas, are deprived of such benefits simply because they are not aware that such programs exist [14,15], which may worsen their QOL relative to those benefiting from those programs. Previous studies on QOL among Nepalese elderly have been limited to the outpatient clinics [16] and nursing homes [17] in Nepal's capital city of Kathmandu. To achieve the SDG, it is important to identify the key factors influencing the health and QOL of the older population and operationalise appropriate policy mechanisms to improve the QOL of the elderly. Therefore, this current study aimed to 1) identify the state of QOL among Nepali older adults and 2) highlight the factors associated with QOL.

Study designs and participants
Data from a previously conducted community-based cross-sectional study was used [18].
The study was conducted among older adults, aged ≥60 years, living in the rural region of Morang and Sunsari districts of Nepal. The data collection took place between January-April 2018. The sample size of 847 was calculated based on following assumptions: prevalence of frailty = 50%, sampling error = 5.0%, CI = 95.0%, design effect = 2 and nonresponse rate = 5.0%. A total of 794 eligible participants agreed to be interviewed using a survey method in the study resulting in a response rate of 93.7%. Study participants were recruited from the community setting using a multi-stage cluster sampling approach. The detail on the sampling method has been fully described in our previously published work [18].

Co-variates measurement
We used semi-structured questionnaire to collect information on socio-demographic profiles, life-style behaviours and multi-morbidity history. Independent variables included were age; gender; ethnicity; religion; marital status; living arrangement; literacy status; occupation; monthly personal income; smoking habit; alcohol drinking habit; tobacco chewing habit; physical activity and presence of any co-morbidities. These co-variates are described in the published paper authored by Yadav et al. [19].
The English version of the questionnaire was first translated to Nepali and then translated (forward-backward translation) back to English by two researchers to check the consistency of the instrument.

Outcome variable
QOL of the older adults was assessed by the Older People's Quality of Life (OPQOL) questionnaire [20], which is a novel instrument specifically designed to measure the QOL of older adults [21]. The OPQOL questionnaire has 35 questions that asked the participant to indicate the extent to which he/she agrees with each item in the Likert scale response (i.e., "strongly disagree", "disagree", "neither agree nor disagree", "agree" and "strongly agree"). Each of the five possible answers is scored between one ("strongly disagree") and five ("strongly agree"). The 35 items of this instrument consider the following aspects of QOL: life overall, health, social relationships and participation, independence, control over life and freedom, home and neighbourhood, psychological and emotional well-being, financial circumstances, leisure, activities, and religion. The cumulative score of the 35 items, which ranged from35 to 175, provides the measure of overall QOL; with higher scores indicating a better QOL. In this study, Cronbach's alpha for the OPQOL instrument was 0.75, which indicates acceptable reliability of the tool.

Ethics
The study was approved by the Institutional Review Board of Nepal Health Research Council, Government of Nepal, Ministry of Health, Kathmandu. Prior to the interview, written informed consent was obtained from all literate participants, and thumb impressions were obtained from illiterate participants. Participants received an oral explanation about the study objectives, procedures and voluntary participation.

Statistical analysis
We employed descriptive, bivariate and multivariable regression models for this study.
First, descriptive analysis was carried out to present the distribution of background characteristics. Frequency, percentage, mean, standard deviation (SD) and range distributions are presented. For the bivariate analysis, the chi-square (χ2) test was performed to compare the percentage of participants with different QOL within different categories of variables at a 5% level of significance. Considering the nested nature of the survey data with possible variations among clusters (municipality), we performed a mixedeffect logistic regression model to assess the true association between the QOL and associated factors. Cluster variation was considered as a random effect and the rest of the variables were considered as fixed effects. The generalized estimating equation (GEE) was undertaken to estimate the parameters of the model while the exchangeable correlation structure within the clusters was employed. We retained in the final model only variables with a p-value of less than 0.25 in the bivariate model. Both unadjusted and adjusted odds ratios (ORs) are reported with 95% confidence intervals (95% CI). All analyses were performed using Stata v. 13.0 (Stata Corp, College Station, TX).

Descriptive statistics
A total of 794 older adults aged 60 years and above participated in the study. The mean age of the participants was 69.9 years; more than half (55.4%) were in their sixties ( Table 1). The male to female ratio was close to unity (50.4% and 49.6%, respectively). A greater proportion of the participants were Hindu (78.7%) and illiterate (80.1%). Nearly 38% of the participants were of indigenous origin, and 34% were from the Madhesi and other ethnic groups. About half of the participants (53.8%) were married at the time of the survey. Regarding occupational status, 54.2% of the participants were not involved in any income-generating activities. As such, around half of the participants had a family income of 5000 NRs or less. More than three-quarters of the participants had no physical activity at all (77.1%) and tobacco consumption history (76.8%), while only a quarter (25.1%) had alcohol drinking habits (Table 1). Depression (55.8%), osteoarthritis (41.7%), and chronic obstructive pulmonary disease (COPD) (15.4%) were the most prevalent health conditions among the participants ( Table 2).

Chronic condition and QOL
The Chi-square test for the relationship between chronic conditions and QOL showed that participants with prevalent osteoarthritis (p-value < 0.001), COPD (p-value < 0.001), and depression (p-value < 0.001) had significantly poor QOL ( Table 2).

Summary of QOL indices
The numeric indices of QOL scores by different domains are presented in

Association of risk factors with QOL
The multiple logistic regression model to assess the determinants of QOL is presented in

Discussion
This study aimed to assess the QOL and its correlates among older adults in Eastern Nepal and found that seven in ten participants had poor QOL, which was significantly associated with age, socioeconomic status, religion, ethnicity, physical activity, osteoarthritis, and depression.
The overall poor QOL observed in this study is consistent with previous studies from Nepal's capital city of Kathmandu, where older patients in an outpatient clinic [16] and nursing homes [17] settings, had a lower overall QOL score. Previous studies, from international settings, are in line with our findings [22,23]. Further, a gradient decline in the odds of poor QOL was noted by increasing age group which is in line with a previous study from Nepal where age was inversely associated with QOL [24]. The declining QOL with age is plausible, given that older adults are at increased risk of chronic diseases and infection [6,25]. Furthermore, age is associated with a progressive decline in muscle mass, strength, power, and physical performance [8,9]. As a result, they have reduced mobility and functional capacity which ultimately influences the overall wellbeing and lowers the QOL at later life [8,9].
A significant finding of this study is the role of socioeconomic status and its implications for QoL. Better socioeconomic status, as indicated by literacy and higher income in this study, was associated with higher QOL among older adults in our study as well as others [26][27][28]. Socioeconomic status is considered as one of the driving forces for the existing health disparities globally [29]. Given the well-established relationship between socioeconomic status and well-being, in terms of perceived health [30], mortality, and morbidity [31,32], the observed association with QOL was anticipated. Education increases health literacy and influences one's ability to make informed decisions about their health and healthy behaviours [33]. Likewise, income increases purchasing capacity, access to health care, and affordability of everyday need [34]. Together, education and income may determine one's social status and the psychosocial advantages gained through social networks [34]. Specifically, among the older adults from the life-course approach to aging, the better SES may reflect the relative advantages, in terms of better economic and social positions, accumulated over the life course that may lead to better QOL in later life [35].
Similar to prior studies [36,37], physical activity among the elderly was associated with QOL. The role of physical activity in the reduction of risk of chronic diseases and premature mortality, as well as the promotion of physical functionality and health in the general population, is well established [38][39][40]. However, within the confines of this population, it provides evidence for the continual effect of physical activity over the life course. The pathways linking physical activity with QOL may be through the prevention of chronic diseases and the promotion of physical functioning and overall well-being.
Previously, among older adults, several mediators such as better physical and mental health status increased exercise self-efficacy, increased physical self-worth, and reduced disability limitations, has been identified in the pathways between increased physical activity and QOL [36,37].
In the context of Nepal, an individual's ethnicity has similar effects as their socioeconomic status. Hence, it is not surprising to find that ethnicity was associated with QOL.
Thus, compared to Brahmin/Chettri/Thakur, which is considered as the upper caste, participant's from Indigenous, Dalit, and Madhesi/other ethnic groups had 75%, 77%, and 71% lower odds of having good QOL respectively. This is consistent with previous studies from Nepal, which have also suggested lower QOL scores among Dalits than the upper castes, although the findings were statistically non-significant [16,24]. Likewise, our finding aligns with the established notion that the Madhesi, Dalits, and Indigenous, being one of the marginalised groups, have poor outcomes in health and wellbeing, and socioeconomic status [41,42]. Historically, these ethnic groups were considered disadvantaged in the society, in terms of their access to education and employment, and were discriminated against by the upper caste groups. Although, in recent years, such discrimination against them is criminalised by the law and many organisations are in place to uplift their social mobility, the quest for equality is still a long journey, especially in rural parts where illiteracy is high and traditions are deep-rooted [4]. This finding may suggest that the ethnic group you are born into may determine your QOL.
Another significant finding made from this study is the significant association between religiosity and QOL. Here, compared to a Hindu participant, QOL was higher among Buddhist participants and lower among Christian participants. Although the underlying explanations for the observed differences in QOL by religion are unknown, the literature does suggest that spirituality and religiosity are important components of QOL at any age [43]. Religious involvement may buffer stress and increase happiness, meaning, purpose, hope in life, which ultimately leads to better QOL [44]. Future studies have the opportunity to delve more on the observed association between religion and QOL; specifically, qualitative studies may be helpful to explore minority participant's perceptions.
Physical and mental ailments were associated with lower QOL. Absence of osteoarthritis and depression was associated with higher odds of better QOL. Previously, low perceived QOL among patients with osteoarthritis is reported [45,46]. The pain and limitations of daily living activities resulting from osteoarthritis may explain the observed reduced QOL [46,47].
Our findings of an inverse association between QOL and depression are consistent with previous studies from Nepal and globally [23,48,49]. A meta-analysis of 24 studies reported moderate improvements in QOL following treatments for depression [50].
Depression may lower the QOL by impairing physical and social functioning, and overall health [51].

Strengths and limitations
As with most studies, this study has some limitations. The participants were from eight rural municipalities of Morang and Sunsari district, Nepal; thus, the results can be only generalized to the studied setting. Secondly, social-desirability bias may have occurred as our findings relied on self-reported data. Further, the study adopted a cross-sectional design, which precludes any inferences of the cause-effect relationships. The most important strength of this study includes a large sample size with more than 90% response rate, strong methodology, and adoption of Older People's Quality of Life (OPQOL) questionnaire for the first time in Nepalese settings.

Conclusion
This study has provided statistical evidence of the factors influencing the good QOL among the elderly in Nepal. The current study shows that one in three respondents have a good QOL. In delineating the mechanism by which this happens, the results demonstrate

Funding
The UNY received funding from Nepal Health Research Council, Ministry of Health, Government of Nepal (Provincial grant). The funders had no role in the study design, data collection and analysis of the data.

Availability of data and materials
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics approval and consent to participate
The study was approved by the Institutional Review Board of Nepal Health Research Council, Government of Nepal, Ministry of Health, Kathmandu. After detailed information, all study participants gave their written informed consent.

Consent for publication
Not applicable.