Mediation and moderated mediation in the relationships among income condition, depression, cognition and residence among older adults in China

Abstract

Aim: A better income condition has always been associated with better cognition; however, studies that have demonstrated the pathway of this relationship are limited. We aim to evaluate the mediation effect of depression in this association, and whether this mediation is moderated by the place of residence. Methods: We conducted a face-to-face study, including 3230 older adults aged >60 years in Xiamen, China, in 2016. The income condition of participants was categorized into three groups: income less than expenditure, income equals expenditure and income more than expenditure. Depression was measured using the Geriatric Depression Scale and cognition was evaluated using the Montreal Cognitive Assessment tool. We first examined a simple mediation model where depression was a mediator between income condition and cognition. Furthermore, residence was systematically integrated into the model as a moderator, and the model was adjusted for age, gender, number of year of education, hypertension and diabetes. All mediation and moderated mediation effects were estimated by the plug-in "PROCESS" in SPSS. Results: In total, 2852 participants were finally included. Depression partially mediated the relationship between income condition and cognition (indirect effect = 0.25, total effect = 0.72). Moderated mediation analyses indicated that a direct effect only existed among urban older adults (B = 0.92; 95% confidence interval [CI]: [0.47-1.38]), whereas an indirect effect was stronger for individuals in urban (B = 0.28; 95% CI: [0.18-0.41]) rather than rural environments (B = 0.17; 95% CI: [0.11-0.26]). Conclusions: A better income condition is a protective factor for cognition and it partially benefits work through milder depressive symptoms, particularly in older adults in urban residences.

Does Participation in Local Non-agricultural Employment Improve the Mental Health of Elderly Adults in Rural Areas? Evidence From China

“…The association between income status and mental health has been reported in the literature. Existing studies reveal that, income status obtained by individuals has a significant influence on their health outcomes, including their mental and physical health, particularly in the case of elderly adults (31)(32)(33)(34). Further, findings from (35) reveal that, the likelihood of depressions, mental disorders, and anxiety decrease when economic status or income level rise.…”

“…Findings from the hypothesized relationships demonstrate that satisfaction of belongingness and respect, the improvement of income, and the exertion of human capital also have positive direct influence on the mental health of the elderly who participate in the local non-agricultural employment. The plausible explanation is that, the elderly adults who are employed or participate in self-employment are able to improve their income levels, ease any financial burden, and improve their life satiation, well-being, and mental stress, which are all indicators of a sound mental health (31)(32)(33)(34). Again the continuous utilization of the physical strength, human capital and professional skills of the elderly contribute significantly to their mental health.…”

Examining the impact of socioeconomic status, demographic characteristics, lifestyle and other risk factors on adults' cognitive functioning in developing countries: an analysis of five selected WHO SAGE Wave 1 Countries

“…Furthermore, the type of residency (rural or urban) significantly predicted cognitive functioning in all the selected countries. A study by Yuan et al 2020 observed that individuals residing in an urban area have better cognition [ 36 ] due to perceived better income conditions than their counterparts in rural residences. This study observed that most respondents in China, Ghana, and India lived in rural areas.…”

“…Studies by Sundström et al 2016 and Feng et al 2014 revealed that unmarried adults have a high propensity of suffering from cognitive impairments leading to dementia than married adults [ 34 , 35 ]. Previous research has also observed that rural dwellers tend to have a significantly higher prevalence of cognitive limitations than their counterparts in urban residences [ 36 , 37 ]. Research on the association between sex and cognitive functioning has produced mixed results.…”

Risk factors for suicidal behavior in late‐life depression: A retrospective preliminary clinical study

“…Therefore, targeting extra risk factors related to SB among the elderly population with depression could significantly reduce suicides. Similar to the case in other age groups, the elderly commit suicide because of the combined effect of psychic, mental, physical, social, and cultural concerns, suggesting a high heterogeneity in late‐life suicide 6,7 . For example, impulsivity is considered to be the SB endophenotype, but many elderly people who attempt suicide have shown low impulsivity.…”