The impact of race on olfaction: A systematic review and meta‐analysis

Abstract Background Many studies have identified a higher degree of Olfactory Dysfunction (OD) in Black patients compared to White patients. This study aims to analyze olfactory outcomes in different races. Methods The PubMed, Scopus, and CINAHL databases were searched from inception to September 5, 2022, for English‐language articles documenting self‐reported and psychophysical OD stratified by race. A meta‐analysis of proportions, comparison of weighted proportions, and comparison of means were performed in MedCalc 20.218. In the quantitative analysis, 79,297 patients were included, comprising 79.3% Whites, 16.1% Blacks, and 4.6% Hispanics. Results A total of 14 studies were meta‐analyzed. The prevalence of self‐reported OD in Hispanic, White, and Black patients was 19.5% (95% CI, 16.6% to 22.6%), 17.2% (95% CI, 10.5% to 25.0%), and 13.9% (95% CI, 9.3% to 19.2%), respectively ( p < 0.0007). The prevalence of psychophysical OD in Black, White, and Hispanic patients was 30.3% (95% CI, 24.2% to 36.9%), 24.2% (95% CI, 20.1% to 28.5%), and 18.4% (95% CI, 16.3% to 20.7%), respectively ( p < 0.0001). Blacks reported a greater extent of unrecognized OD compared to Whites, with a difference of 16.5% (95% CI, 15.0% to 17.9%) versus 5.8% (95% CI, 3.4% to 8.0%), respectively ( p < 0.0001). Hispanic rates of self‐reported OD and psychophysical OD were not statistically different. Conclusions Our findings suggest that Blacks have the highest rate of psychophysical OD and are more likely to underreport their awareness compared to Whites.