Polypharmacy in T2D may increase susceptibility to bone fractures

Type 2 diabetes (T2D) patients who are taking multiple medications together are at heightened risk of bone fractures, a study has found.

Using data from the Fukuoka Diabetes Registry, the study included 4,706 Japanese T2D patients (mean age 66 years), among whom 2,755 were men and 1,951 were postmenopausal women. All participants were followed for a median of 5.3 years for the development of fractures at any anatomic site and fragility fractures (those that occur at the hip and spine).

Researchers used multivariable Cox proportional hazards analysis to estimate the risk of bone fractures in relation to the number of prescribed drugs.

Over the follow-up, 662 participants developed any fracture. The overall age- and sex-adjusted fracture incidence increased in proportion to the number of medications used. The corresponding incidence rates were 21.2 per 1,000 person-years among participants taking 0–2 drugs, 28.1 per 1,000 person-years among those taking 3–5 drugs, 37.7 per 1,000 person-years among those taking 6–8 drugs, and 44.0 per 1,000 person-years among those taking ≥9 drug (p_trend<0.001).

Polypharmacy conferred an increased risk of any fractures. Compared with 0–2 drugs, taking 3–5 drugs was associated with a 34-percent risk increase (adjusted hazard ratio [HR], 1.34, 95 percent confidence interval [CI], 1.07–1.68), 6–8 drugs with a 76-percent higher risk (HR, 1.76, 95 percent CI, 1.37–2.26), and ≥9 drugs with a 71-percent greater risk (HR, 1.71, 95 percent CI, 1.27–2.31).

Every increment in drugs used correlated with a 5-percent increase in the risk of any fractures (HR, 1.05, 95 percent CI, 1.02–1.08; p<0.001).

A similar pattern of results was observed for fragility fractures.