Predicting Recovery from Smell Loss

This was a longitudinal study of predictors of recovery in 542 people who complained of smell loss due to various causes, including trauma, infection, surgery, and medical treatments. Testing was conducted at baseline (mean time since smell loss, 1.08 years) with the 40-odor University of Pennsylvania Smell Identification Test (UPSIT) and an average of 2.9 years later (range, 3 months to 24 years) with the 40-odor UPSIT or a 12-odor version. (One of the study authors is a shareholder in the company that manufactures the smell test used.)

From baseline to follow-up, 11.3% of anosmic and 23.3% of hyposmic patients regained their age-adjusted sense of smell (although significant improvement occurred in 56.7% and 42.7%, respectively). Age, initi…