The association of frailty with olfactory and gustatory dysfunction in older adults: a nationally representative sample

BACKGROUND: Olfaction and gustation are associated with age-related decline. Deficits in these chemosenses have been associated with significant comorbidities. Meanwhile, frailty, defined as a reduced physiological reserve, is well correlated with mortality and worse health outcomes. We sought to analyze a nationally representative patient population to determine the association between chemosensory dysfunction and frailty. METHODS: Cross-sectional analysis of U.S. National Health and Nutrition Examination Survey (NHANES) 2013-2014 was performed, using multivariate logistic regression to examine the association between chemosensory dysfunction and frailty in adults aged ≥40 years (n = 3547). Self-reported olfactory dysfunction (sOD) and gustatory dysfunction (sGD), and measured olfactory dysfunction (mOD) and gustatory dysfunction (mGD) were assessed for all participants. Frailty was operationalized using a 39-item frailty index (FI) and stratified into 4 groups using validated cutoffs. RESULTS: Participants with sOD and mOD had significantly higher mean FI scores (sOD: 0.18 vs 0.13, p < 0.001; mOD: 0.20 vs 0.14, p < 0.001), whereas subjects with sGD, but not mGD, had higher mean FI scores (sGD: 0.21 vs 0.13, p < 0.001; mGD: 0.14 vs 0.14, p = 0.953). Multivariate logistic regression demonstrated frail participants had significantly greater odds of sGD (odds ratio [OR] 4.11; 95% confidence interval [CI], 3.46 to 4.88), sOD (OR 2.35; 95% CI, 1.98 to 2.78), and mOD (OR 1.58; 95% CI, 1.22 to 2.05), but not mGD (OR 1.21; 95% CI, 0.91 to 1.61). This association was strongest in the frailest group. CONCLUSION: Self-reported chemosensory dysfunction and mOD are independently associated with measures of frailty, suggesting a novel method to assess or predict frailty.