[Odor perception in relation to age, general health, nutritional status, and dental status]

Many studies have shown that odour perception declines with age. Considering the possible role of age-related phenomena such as general health, dental health and nutrition in such a decline, their joint effect on variability in odour perception was evaluated in the present study. 73 apparently healthy adults aged from 53 to 86 years (median age = 66), living in the community, took part in this study. The SENIEUR protocol was used to assess the general health status and anthropometric measures were obtained to assess the nutritional status. The sensory detection threshold for isoamylacetate (banana odour) was determined as the lowest detectable odour concentration. Dental status was assessed by a questionnaire on the presence of natural teeth and wearing of dentures. Those in poor general health had significantly higher mean odour thresholds (2.35, SD = 1.34), where threshold concentration was expressed as -log(mol/l), than those in good (3.47, SD = 1.46) or reasonably general health (3.75, SD = 1.02). Partial denture wearers had significantly higher odour thresholds (2.99, SD = 1.12) than those having only natural teeth (4.24, SD = 1.43). Significant correlations between age and anthropometrical values were found, indicating that with age, muscle mass particularly in women decreases (r = -0.50). Odour perception of women correlated significantly inversely with triceps skinfold thickness (r = -0.42), indicating that poor sense of small is associated with high body content of fat. Our results indicate that general health and dental state are important age-associated factors in odour perception. Since age does not show a significant independent effect, neither in an analysis of variance, nor in a multiple regression analysis, such factors tend to become more important than chronological age per se.