Abstract
BACKGROUND: The COVID-19 pandemic increased social isolation in older adults, promoting mental and cognitive decline. The impact of social media on these effects remains unclear. AIM: To investigate the long-term association of social isolation with mental and cognitive health in older adults and whether social media use mitigated this association. METHOD: Data from the Norwegian Trøndelag Health Study before (2017-2019), during (January 2021), and after the pandemic (2021-2023) were analysed (N = 4844, 53% women, mean age 80 years). Multi-adjusted mixed-effects linear regression estimated differences in changes in mental (CONOR-MHI) and cognitive (MoCA) health related to self-reported social isolation and social media use. Beta (β) represents differences in change in z-score of CONOR-MHI or MoCA. RESULTS: Social isolation was associated with a steeper decline in mental health than no social isolation (β = 0.07, 95% CI 0.01, 0.13) but was not associated with change in cognitive health. Daily social media use was not related to change in mental health, whereas it was associated with a less steep cognitive decline than no social media use (< 1 h: β = 0.13, 95% CI 0.05, 0.20; ≥ 1 h: β = 0.10, 95% CI 0.01, 0.15). Stratified by social isolation, daily social media use < 1 h was related to a less steep cognitive decline than no social media use in both isolated (β = 0.15, 95% CI 0.02, 0.28) and non-isolated individuals (β = 0.13, 95% CI 0.03, 0.22). CONCLUSION: Individuals experiencing social isolation during the pandemic had a steeper decline in mental, but not cognitive health, compared to those not isolated. Social media use did not buffer the decline in mental health but was associated with less steep cognitive decline. The pandemic showed limits of relying solely on digital solutions for social contact. TRIAL REGISTRATION: The study is registered in ClinicalTrials.gov 18.02.2021, with the identification number NCT04792086.