The Impact of Socioeconomic Factors on Cognitive Ability in Community-Dwelling Older Adults: Mediating Effect of Social Participation and Social Support.

BACKGROUND AND PURPOSE

Previous studies have shown that socioeconomic status influences cognitive health in adults. Therefore, it is important for the development of healthy aging policies to further investigate the effect of specific socioeconomic factors on cognitive function in older people and the possible mechanism. In this study, three specific socioeconomic factors (i.e., income, occupation, and education) were used as independent variables, and social support and social participation were used as the parallel or serial mediating variables to investigate the effect on cognitive function in community-dwelling older adults and the specific pathway of influence.

METHODS

A cross-sectional study was conducted in the Pudong New District of Shanghai, China. A total of 970 community-dwelling older adults aged over 60 years old who had lived in their current location for more than 5 years were enrolled. Socioeconomic factors in older adults, including income, education level, and occupation before retirement, were investigated, and their cognitive function and social support and social participation levels were measured using the MoCA, MSPSS, and the quantity of participation in social activities, respectively. Covariates, including lifestyle, health status, sleep quality, and nutritional status, were assessed using a self-designed questionnaire, the PSQI, and the MNA-SF scale. Omnibus mediation effect analysis was adopted to examine the mediation effect, and the mediation analysis was performed using the SPSS PROCESS program.

RESULTS

Community-dwelling older adults with higher income, more complex occupation, or higher education level had a better cognitive function, with β = 1.949 and β = 3.799 compared to low-income level (all < 0.001), β = 1.262 and β = 1.574 compared to low occupational complexity level (all < 0.01), and β = 1.814 and β = 1.511 compared to low education level (all < 0.001). Social participation significantly mediated the above relationship (all < 0.001); the relative indirect effect of medium and high income through social participation was respectively β = 0.356 and β = 0.777 compared to low income, accounting for 18.36% and 20.45% of the total effect; the relative indirect effect (β) of medium and high occupational complexity compared to low level of occupational complexity was 0.358 and 0.561, accounting for 28.36% and 35.64% of the total effect; while the relative indirect effect (β) of medium and high education compared to low education level was 0.311 and 0.562, with 17.14% and 39.19% of the total effect. Social support significantly mediated the relationship of income and education with cognitive function (all < 0.001), with the indirect effect (β) of medium and high levels of income or education compared to their low levels being 0.132 and 0.160, or 0.096 and 0.156, respectively, accounting for 4.21% and 6.77%, or 5.29% and 10.32%, of their total effects. Serial mediation analysis showed that income and education significantly affected social participation through social support and subsequently cognitive function (all < 0.01), with the relative serial indirect effects (β) of medium and high levels of income or education compared to their low levels being 0.065 and 0.078, or 0.043 and 0.070, respectively, accounting for 3.3% and 2.0%, or and 2.4-4.6% of their total effects.

CONCLUSIONS

This study demonstrates that social support and social participation independently and cumulatively mediate the relationship between socioeconomic conditions and cognitive function in community-dwelling older adults. Therefore, improving the social support systems and encouraging older adults to actively participate in social activities may be beneficial in preventing or improving cognitive decline in community-dwelling older adults. The findings also provide new insights for the future improvement of cognitive function in community-dwelling older adults in the future.