Diet quality in midlife not linked to later risk for dementia

(HealthDay)—Diet quality in midlife is not associated with subsequent dementia risk, according to a study published in the March 12 issue of the Journal of the American Medical Association.

Tasnime N. Akbaraly, Ph.D., from the University Research and Hospital Center of Montpellier in France, and colleagues examined the correlation between midlife diet and subsequent dementia risk. Data were included for 8,225 participants without dementia in 1991 to 1993 (mean age, 50.2 years).

The researchers found that during 24.8 years of follow up, 344 cases of incident dementia were recorded. There was no significant difference in the incidence rate for dementia according to tertiles of the 11-component diet quality Alternate Healthy Eating Index (AHEI) exposure during 1991 to 1993, 1997 to 1999, and 2002 to 2004. In the lowest tertile of diet quality in 1991 to 1993, the incidence rate for dementia was 1.76 per 1,000 person-years; the absolute rate difference was 0.03 (95 percent confidence interval, −0.43 to 0.49) and 0.04 (95 percent confidence interval, −0.42 to 0.51) per 1,000 person-years for the intermediate and best quartiles, respectively. The adjusted hazard ratios for dementia for one-standard deviation AHEI increment were not significant as assessed in 1991 to 1993, 1997 to 1999, or 2002 to 2004 in the multivariable analysis.

"Whether a healthy diet plays a role in shaping cognitive outcomes in combination with other healthy behaviors or in subgroups at increased risk for dementia remains unclear," the authors write.