Excess Risk for Hip Fracture with Subclinical Hyperthyroidism

The effect of subclinical thyroid dysfunction on bone is unclear. In this meta-analysis, researchers identified 13 prospective cohort studies (>70,000 patients; median age, 64) in which baseline thyroid-stimulating hormone (TSH) and free thyroxine (T₄) levels were measured and follow-up fracture rates were reported. About 6% of participants had subclinical hypothyroidism (TSH levels, 4.50–19.99 mIU/L; normal T₄), and 3% had subclinical hyperthyroidism (TSH levels, <0.45 mIU/L; normal T₄). Median follow-up was 12 years.

In adjusted analyses, patients with subclinical hyperthyroidism were significantly more likely to sustain hip fractures than were euthyroid patients (6.0 vs. 4.9 per 1000 person-years) and had significantly higher risk for any…