The association of a priori and a posterior dietary patterns with the risk of incident stroke in Chinese older people in Hong Kong.

Background: Dietary patterns can be identified by a priori and a posterior approaches. Limited data have related dietary patterns with stroke risk in Chinese population. This study examined stroke risk associated with patterns identified by both approaches.

Methods: Data on 1,338 Chinese men and 1,397 Chinese women aged >= 65 years participating in a cohort study examining the risk factors for osteoporosis in Hong Kong were analyzed. Baseline dietary data were collected between 2001 and 2003 using a validated food frequency questionnaire. Adherence to a priori dietary patterns including the Mediterranean Diet Score (MDS) and the Dietary Approaches to Stop Hypertension (DASH) was assessed. Factor analysis (FA) identified three a posterior dietary patterns: "vegetables-fruits", "snacks-drinks-milk products", and "meat-fish". Data on incidence of stroke were retrieved from an official database in 2008. Cox regression was used to estimate hazard ratios (HRs) for stroke risk adjusted for potential confounders.

Results: There were 156 incident stroke events during a median follow up of 5.7 years. A posterior dietary patterns derived by FA were not associated with risk of incident stroke in either men or women. MDS was inversely associated with risk of incident stroke [Adjusted HR=0.55 (95% CI: 0.31-0.99) of the highest level of MDS compared with the lowest level, ptrend=0.008] in men but not in women. Similar non-significant inverse association was observed between DASH accordance and stroke risk in men [Multivariate HR (95% CI) of the DASH score of >=4.5 = 0.62 (0.38-1.04) compared with the DASH score of <=4, ptrend = 0.068] but not in women.

Conclusion: Our findings suggest that higher MDS and possibly higher DASH scores were associated with lower stroke risk in Chinese older people in Hong Kong.