Carbohydrate quality index and mortality risk in older adults at high cardiovascular risk

Abstract

Carbohydrate quality may influence long-term health, but its relationship with mortality in older adults remains unclear. We examined the association between carbohydrate quality and all-cause and cause-specific mortality in 7210 older adults at high cardiovascular disease risk from the PREDIMED trial. Carbohydrate quality was assessed using a cumulative average carbohydrate quality index (CQI), combining glycemic index, dietary fiber intake, whole-grain-to-total grain ratio, and solid carbohydrate-to-total carbohydrate ratio, derived from repeated validated food frequency questionnaires. During a median follow-up of 6 years, 425 deaths occurred, including 103 cardiovascular, 169 cancer, and 153 other-cause deaths. In multivariable-adjusted Cox regression models, higher CQI was associated with lower cancer mortality, while participants in the lowest CQI quintile had higher risks of all-cause and cancer mortality compared with those with higher CQI scores. Dietary fiber and whole-grain intake appeared to be the main CQI components driving these associations. These findings suggest that improving carbohydrate quality, particularly through higher intake of fiber-rich and whole-grain foods, may contribute to lower mortality risk in older adults at high cardiovascular risk.