Risk Factors for Incident Fracture in Older Adults With Type 2 Diabetes: The Framingham Heart Study

Abstract

Objective: To identify risk factors for fracture in type 2 diabetes.

Research design and methods: This prospective study included members of the Framingham Original and Offspring Cohorts. Type 2 diabetes was defined as fasting plasma glucose >125 mg/dL or use of type 2 diabetes therapy. We used repeated-measures Cox proportional hazards regression to calculate hazard ratios (HRs) and 95% CIs for associations between potential predictors and incidence of fragility fracture.

Results: Participants included 793 individuals with type 2 diabetes. Mean ± SD age was 70 ± 10 years; 45% were women. A total of 106 incident fractures occurred over 1,437 observation follow-up intervals. Fracture incidence increased with age (adjusted HRs 1.00, 1.44 [95% CI 0.65, 3.16], and 2.40 [1.14, 5.04] for <60, 60-70, and >70 years, respectively; P _trend = 0.02), female sex (2.23 [1.26, 3.95]), HbA_1c (1.00, 2.10 [1.17, 3.75], and 1.29 [0.69, 2.41] for 4.45-6.46% [25-47 mmol/mol], 6.50-7.49% [48-58 mmol/mol], and 7.50-13.86% [58-128 mmol/mol]; P _trend =0.03), falls in past year (1.00, 1.87 [0.82, 4.28], and 3.29 [1.34, 8.09] for no falls, one fall, and two or more falls; P _trend =0.03), fracture history (2.05 [1.34, 3.12]), and lower grip strength (0.82 [0.69, 0.99] per 5-kg increase). Femoral neck bone mineral density, BMI, smoking, physical function, chronic diseases, medications, and physical function were not associated with fracture incidence.

Conclusions: Prior falls, fractures, low grip strength, and elevated HbA_1c are risk factors for fractures in older adults with type 2 diabetes. Evaluation of these factors may improve opportunities for early intervention and reduce fractures in this high-risk group.