Many of the studies examining correlations between frailty and various factors have been cross-sectional in design. Few have examined the same question that is the focus of our study. The closest study to ours that we have been able to find was that by Mulasso et al. (46). They investigated the differences in psychosocial factors among healthy, pre-frail, and frail older people (N=210) and examined the presence of any interactions between frailty status and psychosocial factors. They reported a close relationship between frailty and psychosocial factors, and recommended that when studying human functioning, both the physical and psychological aspects of a person must be considered. We have made a similar observation but have identified the environment (WHOQOL-Environment domain) as also playing an important role in mental health.
The environmental domains of the WHOQOL include the concepts of financial resources, home environment, physical safety and security, accessibility and quality of health and social care, transportation, chances to participate in leisure activities, and the physical environment such as pollution and climate (47). Because physical functioning, comorbidities, and aspects of quality-of-life domains (WHOQOL-Psychological and Environment) were found in our sample to affect cognitive functioning, depressive symptoms, and the sense of loneliness, these three aspects will be discussed.
Despite the methodological differences in the reviewed studies, Miyamura et al. (48) observed that most studies reported that frailty syndrome is a trigger for cognitive decline. Another systematic review (49) revealed that all 19 eligible studies confirmed a link between cognition and frailty. However, we found that cognition would be affected even when the individual’s frailty status remained the same. One of the main findings in our study is the significant association between vision and functional health variables and deterioration in cognitive performance. Like Armstrong et al. (50), our results showed an association between cognitive change and functional performance and vision.
Lohman et al. (51) studied the correlation between frailty and depression and found significant correlations (correlation coefficients 0.61-0.70) between the two conditions in older age. Our study observed that depressive symptoms were predicted by comorbidity, IADL, and WHOQOL-Psychological and WHOQOL-Environment. Jafari et al. (52) examined the relationship between frailty state and mood, cognition, quality of life, and level of independence over a 1-year period in patients with chronic kidney disease. In their study, the trajectory for depression and cognitive impairment exhibited no change at the 12-month follow-up (N=97 at baseline and n=62 at the 1-year follow-up). The decline in the quality of life dimensions (mobility and self-care) in their study pointed to a need to provide more caregiving support over a 1-year period; whereas our study found that depressive symptoms increased in the presence of poor vision, a decline in the performance of IADL, and a deterioration in the WHOQOL psychological and environmental domains, even though there was no change in the baseline frailty status (frail or pre-frail) in the participants. Our findings are in line with those reported by Lohman et al. (51) that the strongest predictors of comorbid depression and frailty were variables related to personal and environmental resources, referring to variables such as less educational attainment, lower levels of income, and less health insurance coverage. Regardless of the direction of the relationships and interactions between frailty and depression, depression is treatable. Early identification and treatment of depressive symptoms in frail older adults would be useful in reducing morbidity and mortality (16).
Loneliness has been defined as an individual’s personal, subjective sense of lacking desired levels of affection, closeness, and social interaction with others (50). We found that increasing age was not associated with increasing levels of loneliness, which was different from the views in other studies, which generally report that the risk of loneliness increases with age (52, 53). A possible reason for this difference is that slightly more than 50% of the data in this measure were missing. Statistical references suggest that an analysis that is conducted when more than 40% of the data are missing should be considered only as hypothesis generating (54). The UCLA Loneliness Scale has several positively worded items that our participants found to be difficult to understand and rate, therefore, led to a higher percentage of incompletions.
Reportedly, groups experiencing loneliness and/or isolation are more likely to have both poorer physical and mental health (55). People with multi-morbidities such as people who are frail, are indeed more vulnerable to social isolation. Yet not all socially isolated people feel lonely, and not all who feel lonely are socially isolated (56).
In our study, loneliness was affected by a decrease in the level of WHOQOL-Environment. Previously, discussions in the health care field about the environment focused on how it impacted people’s functional performance. In recent decades, the influence of various facets of the environment upon psychosocial well-being has gained greater recognition. van Herwijnen (57) suggested that factors such as accessibility and green space influenced loneliness among her participants. van den Berg et al. (58) found that characteristics of the built environment explained a substantial part of the variance in levels of loneliness. The relationship between environmental factors and loneliness is likely complex and warrants further study.
Visual impairment is known to be associated with a pronounced loss that significantly affects the quality-of-life of individuals because of prolonged period of morbidity (59). Yet the global prevalence of preventable visual impairment and blindness in people aged 50 years and above is 9.58 cases per 1000 persons, a rate that has not changed since the last decade (60). Because effective interventions are available for the prevention, treatment, and rehabilitation of eye conditions (61), clinicians should actively promote eye health and engage their patients in self-management. Many interventions, such as self-management and disease management efforts, show promise for use among visually impaired older adults (62).
Depression is a major cause of disability worldwide (63). It is more common in late life, yet it is often underdiagnosed and undertreated (64). As the largest group of healthcare providers, nurses come into contact with older adults on many occasions and in different contexts. Evidence-based interventions are available for nurses to use in caring for affected older adults (65). The same can be said of physicians and other healthcare professionals.
Supportive environments are a key determinant of health, and frail older adults will require a broad range of support services to age in their own home. A systematic review of the evidence supports that a holistic response to frailty would optimize functional performance among older adults across care settings (66). Ageing and health has long been dichotomized into medical (or health) and social perspectives. In recent decades there have been calls for an integration of both perspectives so that a person-centred approach can be adopted (67). This certainly would be an appropriate direction for the healthcare sector to move forward.
The small sample size is a clear limitation. As such, caution is needed when interpreting the results. Future research with larger samples will be needed to examine pathways and possible interactions in the relationships between physical and mental health in older adults. Funding constraints affected our ability to closely follow up the participants. The large percentage of missing data on the UCLA Loneliness Scale generated hypotheses for testing, but unable to offer more insights to help clinicians better understand the phenomenon of interest. The use of a more culturally sensitive tool may facilitate researchers to capture data in future studies. Since little attention has been paid to factors associated with the psychological, cognitive, and social aspects of health and frailty, our findings add value to the literature in this regard.