Carbohydrate nutrition and inflammatory disease mortality in older adults

Background: Several studies suggest that carbohydrate nutrition is related to oxidative stress and inflammatory markers. Objective: We examined whether dietary glycemic index (GI), dietary fiber, and carbohydrate-containing food groups were associated with the mortality attributable to noncardiovascular, noncancer inflammatory disease in an older Australian cohort. Design: Analysis included 1490 postmenopausal women and 1245 men aged [greater than or equal to] 49 y at baseline (1992-1994) from a population-based cohort who completed a validated food-frequency questionnaire. Cox proportional hazards ratios were calculated both for death from diseases in which inflammation or oxidative stress was a predominant contributor and for cardiovascular mortality. Results: Over a 13-y period, 84 women and 86 men died of inflammatory diseases. Women in the highest GI tertile had a 2.9-fold increased risk of inflammatory death compared with women in the lowest GI tertile [multivariate hazard ratio in energy-adjusted tertile 3 (tertile 1 as reference): 2.89; 95% CI: 1.52, 5.51; P for trend: 0.0006, adjusted for age, smoking, diabetes, and alcohol and fiber consumption]. Increasing intakes of foods high in refined sugars or refined starches (P = 0.04) and decreasing intakes of bread and cereals (P = 0.008) or vegetables other than potatoes (P = 0.007) also independently predicted a greater risk, with subjects' GI partly explaining these associations. In men, only an increased consumption of fruit fiber (P = 0.005) and fruit (P = 0.04) conferred an independent decrease in risk of inflammatory death. No associations were observed with cardiovascular mortality. Conclusion: These data provide new epidemiologic evidence of a potentially important link between GI and inflammatory disease mortality among older women. doi: 10.3945/ajcn.2010.29390