Diabetes Increases Risk for Fracture-Related Hospitalization

Miriam E. Tucker

December 26, 2012

Adults diagnosed with diabetes are at significantly increased risk for fracture-related hospitalization, according to results from an analysis of data from a large, community-based study.

The new findings, from the Atherosclerosis Risk in Communities (ARIC) Study, were published online December 17 in Diabetes Care by Andrea L.C. Schneider, PhD, from the Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, and colleagues.

"Our results support recommendations from the American Diabetes Association for assessment of fracture risk and implementation of primary and secondary prevention strategies in appropriate patient populations," the authors write.

Among 15,140 ARIC participants who were aged between 45 and 64 years when the large, 4-community study began in 1987-1989, there were a total of 1078 fracture-related hospitalizations during the 20-year follow-up period. (Only fractures that resulted in inpatient hospitalization were captured in ARIC.)

At baseline, 1195 participants had been diagnosed with diabetes based on self-report and 605 had undiagnosed diabetes according to their measured serum glucose values.

Compared with the 13,340 study participants without diabetes, the incidence of fracture-related hospitalization was significantly greater among the group with diagnosed diabetes (6.6 vs 3.9 per 1000 person-years of follow-up; 95% confidence interval [CI], 5.4 - 7.9 and 3.6 - 4.1, respectively).

The incidence of fracture hospitalization was higher among those with diagnosed diabetes compared with those without diabetes for all age groups. However, the fracture risk was not increased among those with undiagnosed diabetes compared with those without diabetes, the authors note.

After adjustment for the covariates of age, sex, race/study center, body mass index, alcohol consumption, cigarette smoking, sports activity tertile, and use of glucocorticoids, antidepressants, and thiazide diuretics, diagnosed diabetes was still associated with a significantly increased risk for fracture hospitalization, with a hazard ratio (HR) of 1.74 (95% CI, 1.42 - 2.14).

However, also in the fully adjusted analysis, the fracture risk among those with undiagnosed diabetes was similar to that for those participants without diabetes (HR, 1.12; 95% CI, 0.82 - 1.53).

Among just those with diagnosed diabetes, use of oral diabetes medications did not increase fracture risk compared with no diabetes medication use (HR, 0.97; 95% CI, 0.60 - 1.55). However, the use of insulin, with or without concomitant oral medication, was associated with an increased risk for facture (HR, 1.87; 95% CI, 1.15 - 3.05).

After the adjustments, the association of diagnosed diabetes and fracture risk did not differ by age, race, sex, or menopausal status among women.

There was, however, a significant relationship with glycemic control. Among 13,508 participants who had hemoglobin A1c measurements taken at the second ARIC visit (in 1990-1992), there were 976 fracture hospitalizations during the subsequent median of 17 years.

After adjustment, those with diagnosed diabetes who had hemoglobin A1c values of 8% or greater had a significantly greater risk for fracture hospitalization than did those with A1c values less than 8% (HR, 1.63; 95% CI, 1.09 - 2.44). After further adjustment for diabetes medication use, that risk was slightly attenuated (HR, 1.50; 95% CI, 0.97 - 2.32).

In addition to assessing fracture risk among all patients with diabetes, "Our study also suggests that persons with poor glycemic control (defined by [hemoglobin A1c levels] ≥ 8% or the use of insulin) may particularly benefit from aggressive prevention efforts, regardless of age," Dr. Schneider and colleagues write.

Some evidence suggests exercise programs might reduce fracture risk among patients with diabetes, the authors add. "Further studies are needed to understand if exercise interventions or strategies to improve glycemic control while minimizing hypoglycemic episodes may prevent fractures among persons with diabetes."

The ARIC Study was supported by the National Heart, Lung, and Blood Institute. The current research was supported by the National Institutes of Health/National Institutes of Diabetes and Digestive and Kidney Diseases. The authors have disclosed no relevant financial relationships.

Diabetes Care. Published online December 17, 2012. Abstract