Social support, social strain and declines in verbal memory: 16-year follow-up of the English Longitudinal Study of Ageing cohort
Shaun Scholes1 and Jing Liao2,3
1 Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London, WC1E 6BT, United Kingdom.
2 Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, No.74 Zhongshan 2nd Road, Guangzhou, P.R. China.
3 Sun Yat-sen Global Health Institute, Institute of State Governance, Sun Yat-sen University, No.135 Xingang West Road, P.R. China.
Abstract
Objective: Estimate differences in the rate of decline in verbal memory by levels of perceived relationship quality among community dwelling adults. Participants: In the English Longitudinal Study of Ageing (ELSA), n = 10,109 participants aged 50-89 years were assessed at wave 1 (baseline: 2002-03) and followed-up over 16 years to wave 9 (2017-18).
Methods: Verbal memory was assessed bienially by tests of immediate and delayed word-recall. Positive and negative aspects of perceived relationship quality (social support and strain, respectively) were measured by relationship type (spouse/partner; children; extended family members; friends). Random effects within-between (REWB) modelling was used to estimate the associations between levels of social support/strain and (i) baseline levels of memory (main effects), and (ii) the decline in memory per 2-year interval (interaction with time).
Results: Longitudinal associations were most prominent for men, specific to relationship type, and showed between- rather than within-person effects. Faster decline in memory was observed among men with higher levels of spousal strain (-0.043; 95% CI: -0.084, -0.002; p = 0.039). Slower decline in memory was observed among men with greater support from children (0.020; 95% CI: 0.002, 0.039; p = 0.033). Men with higher levels of strain from friends had lower baseline memory (-0.382; 95% CI: -0.627, -0.137; p = 0.002) and showed faster decline (-0.047; 95% CI: -0.095, 0.000; p = 0.051).
Conclusions: Differences between persons in mean levels of social support and social strain were modestly associated with the rate of memory decline, especially among men. Our findings can inform future research studies and intervention strategies designed to maximise the potential role of the qualitative aspects of social relations in promoting healthy cognitive ageing.
Key words: Social support; social strain; memory; cognitive ageing; longitudinal; ELSA