Association between playing cards/mahjong and risk of incident dementia among the Chinese older adults: a prospective cohort study

Objectives: Studies have shown that the frequent participation of the elderly in cognitive stimulation activities is associated with a reduced risk of dementia, but the prospective evidence of this association is limited. Methods: We used data from a prospective cohort study of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), and included 11,821 community-living Chinese individuals aged 65 years or older at 2008 baseline who were free of dementia, and were followed up every 2-3 years until 2018. Cox proportional hazards models were applied to generate the hazard ratios (HRs) and 95% confidence intervals (CIs) for analyzing the associations between the frequency of playing cards/mahjong and the incidence of dementia. Results: A total of 821 participants were diagnosed with dementia during the 10-year follow-up. The average age of patients with dementia and non dementia were 89 and 90 years old, respectively. Compared with participants who rarely or never played cards/mahjong, participants who played cards/mahjong almost every day had a significantly lower risk of dementia (HR = 0.63; 95%CI, 0.42-0.95) after the multivariable-adjusted model. Similar results were observed in subgroup analyses based on sex (male: HR = 0.52, 0.28-0.96; female: HR = 0.62, 0.36-0.98), age (<85years: HR = 0.55, 0.32-0.89), regularly exercise (yes: HR = 0.44, 0.28-0.87) and MMSE score [above median (25): HR = 0.66, 0.41-0.92]. Conclusions: Playing cards/mahjong in the elderly may contribute to reducing the risk of dementia.