Older adults — including those with the apolipoprotein E (APOE) ε4 allele — had slower rates of memory decline when they engaged in a healthy lifestyle, according to a Chinese study. Healthy lifestyle was defined as never or former smoking, never drinking, a healthy diet (at least 7 of 12 eligible food items, regular physical exercise (75 or 150 minutes of vigorous or moderate exercise, respectively, each week), and active cognitive activity and social contact.
In areas representative of the north, south, and west of China, individuals aged 60 years or older were recruited to participate in the population-based, prospective cohort study. At baseline in 2009, participants had normal cognition and underwent APOE genotyping. Followed until death, discontinuation, or Dec. 26, 2019, participants with favorable (4 or more of the healthy lifestyle elements) or unfavorable lifestyles had these outcomes: “29,072 participants were included (mean age of 72.23 years; 48.54% (n = 14,113) were women; and 20.43% (n = 5,939) were APOE ε4 carriers). Over the 10 year follow-up period (2009-19), participants in the favourable group had slower memory decline than those in the unfavourable group (by 0.028 points/year, 95% confidence interval 0.023 to 0.032, P <0.001). APOE ε4 carriers with favourable (0.027, 95% confidence interval 0.023 to 0.031) and average (0.014, 0.010 to 0.019) lifestyles exhibited a slower memory decline than those with unfavourable lifestyles. Among people who were not carriers of APOE ε4, similar results were observed among participants in the favourable (0.029 points/year, 95% confidence interval 0.019 to 0.039) and average (0.019, 0.011 to 0.027) groups compared with those in the unfavourable group. APOE ε4 status and lifestyle profiles did not show a significant interaction effect on memory decline (P = 0.52).”