Bortezomib is a common multiple myeloma therapy that can cause treatment-related peripheral neuropathy, a risk factor for falls. The relationship between bortezomib and falls in older patients with multiple myeloma is unknown.

We analyzed the SEER-Medicare database for patients aged 65 or older diagnosed with multiple myeloma between 2007 and 2013. Claims were analyzed for myeloma treatments, falls, and covariates of interest. We evaluated accidental falls occurring within 12 months after starting first-line multiple myeloma treatment with bortezomib.

Bortezomib was used in first-line therapy for 2052 older adults with new diagnoses of multiple myeloma. Claims for falls were reported in 157 (8%) patients within 12 months after starting bortezomib, compared to 102 (5%) patients not receiving bortezomib (p < 0.001). Bortezomib was associated with a 36% increased risk of falls after controlling for covariates (aHR 1.36; 95% CI 1.05-1.75; p = 0.018). In a landmark analysis of those who survived 12 months after starting treatment, the median overall survival of those with a fall was 35.7 months compared to 49.1 months for those without (p < 0.0001). A fall in the first year after diagnosis was associated with a 26% increased risk in hazard for death (aHR 1.26; 95% CI 1.02-1.56; p = 0.033).

In older adults with multiple myeloma, bortezomib was associated with an increased risk of having a diagnostic code for falls. Decreased overall survival was seen in those who fell within the year of starting therapy. Prospective trials involving fall assessments and fall-prevention interventions are needed in this population.