LAUSR

Objectives This study examined relationships among smell impairment and health in adults over the age of 60 years. We hypothesized that persons with impaired or altered olfaction would be weaker (as shown by hand grip strength tests) and have a lower body mass index (BMI) ratios because they ate less. Methods The 2013-2014 NHANES database was use examined for smell identification scores, general demographic data, handgrip strength, and other types of data. Only persons aged 60 or older who had completed the Mobile Exam Center interview, and the complete smell and grip tests were included (n = 1287). Data were weighted to represent the U.S. population. Smell impairment was defined as five or fewer correct answers in the Odor Identification Test. Data-dependent statistical analyses (t-test, Wilcoxon rank sum, χ2) were performed to find differences based on specific criteria. Odds ratios (OR) with 95% confidence intervals were generated by simple logistic regression, and then a multivariable predictive model was developed. Results The NHANES participants included for these analyses were mainly non-Hispanic white (52.7%), college-educated (54.5%), and lived with someone (60%). The prevalence of smell impairment was 21.7% among persons aged 60 or older, but the prevalence rose to 44.8% among persons aged 75-80. The prevalence of self-reported smell alteration was 16.2%. Smell impairment was significantly associated with age 75-80 years (OR: 3.51, CI: 2.51-3.11), and an educational level of high school or less (OR: 1.70, CI: 1.40-2.30). After adjustment for gender, age, education, and race, smell impairment was associated with poor health self-ratings (OR: 2.63, CI: 1.30-5.40), more sedentary hours each day (OR: 1.07, CI: 1.03-1.11), and presence of smell alteration (OR: 3.00, CI: 2.10-4.60). Persons with normal muscle and hand grip strength were less likely to have a smell impairment or alteration. Conclusions Men aged 75-80 years were more at risk for smell impairment. Further research is needed to determine whether preservation of olfaction can forestall age-related reductions in appetite, and subsequent loss in body mass, particularly muscle. The inclusion of persons older than 80 years in the NHANES sampling would provide useful data for researchers. Funding Sources USDA Hatch funds.