Intakes of dietary fiber, vegetables, and fruits and incidence of cardiovascular disease in Japanese patientswith type 2 diabetes

Abstract

Objective-Foods rich in fiber, such as vegetables and fruits, prevent cardiovascular disease (CVD) among healthy adults, but such data in patients with diabetes are sparse. We investigated this association in a cohort with type 2 diabetes aged 40-70 years whose HbA1c values were ≥ 6.5% in Japan Diabetes Society values. Research design and methods-In this cohort study, 1,414 patients were analyzed after exclusion of patients with history of CVDs and nonresponders to a dietary survey. Primary outcomes were times to stroke and coronary heart disease (CHD). Hazard ratios (HRs) of dietary intake were estimated by Cox regression adjusted for systolic blood pressure, lipids, energy intake, and other confounders. Results-Mean daily dietary fiber in quartiles ranged from 8.7 to 21.8 g, and mean energy intake ranged from 1,442.3 to 2,058.9 kcal. Mean daily intake of vegetables and fruits in quartiles ranged from 228.7 to 721.4 g. During the follow-up of a median of 8.1 years, 68 strokes and 96 CHDs were observed. HRs for stroke in the fourth quartile vs. the first quartile were 0.39 (95%CI 0.12-1.29, P = 0.12) for dietary fiber and 0.35 (0.13-0.96, P = 0.04) for vegetables and fruits. Therewere no significant associations with CHD. The HR per 1-g increase was smaller for soluble dietary fiber (0.48 [95% CI 0.30-0.79], P < 0.01) than for total (0.82 [0.73-0.93], P < 0.01) and insoluble (0.79 [0.68-0.93], P < 0.01) dietary fiber. Conclusions-Increased dietary fiber, particularly soluble fiber, and vegetables and fruits were associated with lower incident stroke but not CHD in patients with type 2 diabetes. © 2013 by the American Diabetes Association.