Abstract
BACKGROUND: Although a number of studies showed a lower risk of hip fractures with high-quality diets, few of them were conducted in the United States. OBJECTIVE: This prospective analysis examined the association between several diet quality indexes and risk of hip fractures in US men and women. DESIGN: This is a prospective cohort study. PARTICIPANTS/SETTING: The participants were 74,446 postmenopausal women from the Nurses' Health Study and 36,602 men aged 50 years and older from the Health Professionals Follow-Up Study in the United States. MAIN OUTCOME MEASURE: Hip fractures were self-reported on biennial questionnaires between 1980-2012 in women, and between 1986-2012 in men. STATISTICAL ANALYSIS: Diet was assessed every 4 years with a validated food frequency questionnaire. Relative risks were computed for hip fracture by quintiles of the Alternate Mediterranean Diet score (aMed), the Alternate Healthy Eating Index-2010 (AHEI-2010), and the Dietary Approaches to Stop Hypertension score using Cox proportional hazards models, adjusting for potential confounders. RESULTS: Two thousand one hundred forty-three incident hip fractures in women and 603 in men were reported during follow-up. A significant inverse trend was observed with the cumulative AHEI-2010 score in women (relative risk comparing extreme quintiles 0.87, 95% CI 0.75 to 1.00; P for trend=0.02). There was also a suggestion of an inverse association with the Dietary Approaches to Stop Hypertension score (P for trend=0.03). In addition, significant inverse trends were observed between all three diet quality scores and hip fractures in women younger than age 75 years but not older women. There was no clear association between diet quality indexes and hip fracture in men. CONCLUSIONS: Higher AHEI-2010 scores were associated with a lower risk of hip fractures in US women. The inverse associations with diet quality may be more apparent among those younger than age 75 years.