Subclinical hyperthyroidism linked to increased fracture risk

Takeaway

• Subclinical hyperthyroidism is associated with increased risk for fracture, whereas subclinical hypothyroidism is not, according to a systematic review and meta-analysis.

Why this matters

• The relationship between thyroid dysfunction and fracture risk was uncertain.

Key results

• Subclinical hyperthyroidism was associated with increased risk for any fracture (relative risk [RR], 1.17; P<.001), hip fractures (RR, 1.27; P=.003), spine fractures (RR, 1.97; P=.001), and nonspine fractures (RR, 1.19; P=.014).
• Subclinical hypothyroidism was not significantly associated with risk for any fracture (RR, 1.14; P=.166), hip fracture (RR, 1.14; P=.068), spine fracture (RR, 0.95; P=.818), or nonspine fracture (RR, 1.09; P=.277).
• Subclinical hyperthyroidism was associated with reduced distal forearm bone mineral density (BMD) in women (P=.039) and lower ultradistal forearm BMD in men (P=.031) and women (P=.027).
• Subclinical hypothyroidism was associated with increased femur neck BMD in women (P=.026).

Study design

• 24 studies (313,557 participants) were included in the meta-analysis.
• Funding: Pudong New Area Health System of Shanghai.

Limitations

• Heterogeneity between included studies.