Benzodiazepine Treatment and Fracture Risk in Young Persons With Anxiety Disorders

Benzodiazepines are commonly prescribed to treat anxiety disorders and have been associated with falls and fractures in older adults. It is unknown whether benzodiazepines increase fracture risk in youth. We examined whether youth with anxiety disorders initiating benzodiazepine treatment have an increased risk of fractures compared with youth initiating selective serotonin reuptake inhibitors (SSRIs).

We used claims from commercially insured children (6-17 years) and young adults (18-24) with a recent anxiety disorder diagnosis, initiating benzodiazepines or SSRIs (2008-2016). Youth were followed until fracture, treatment discontinuation or switching, disenrollment, 3 months, or December 31, 2016. The primary end point was diagnostic codes for upper and lower limb fractures. Incident fracture rates, incident rate ratios (IRRs), and incident rate differences (IRDs) were estimated with propensity score inverse probability of treatment weighting.

The cohort included 120 715 children and 179 768 young adults. In children, crude fracture rates during treatment were 33.1 per 1000 person-years (PYs) for benzodiazepine initiators and 25.1 per 1000 PYs for SSRI initiators. Adjusted IRR and IRD were 1.53 (95% confidence interval [CI]: 0.94-2.50) and 13.4 per 1000 PYs. Risk was heightened in children initiating long-acting benzodiazepines versus SSRIs (adjusted IRR = 2.30 [95% CI: 1.08-4.91]). Fracture rates were lower in young adults, with minimal differences between treatments (adjusted IRR = 0.85 [95% CI: 0.57-1.27]; adjusted IRD = -1.3 per 1000 PYs).

An increased rate of fractures in children, but not young adults, with anxiety disorders initiating benzodiazepine treatment compared to SSRI treatment suggests a need for increased caution in the weeks after benzodiazepine initiation in children.