LONGITUDINAL CHANGES IN SMELL IDENTIFICATION

Background. Cross-sectional studies have demonstrated that olfactory f unction diminishes with increasing age, which may impact on the safety and quality of life of older persons. To date, however, there have be en no published longitudinal studies on olfaction. The purpose of this study was to examine the influence of age and gender on smell identif ication over a 3-year period in a group of generally healthy men and w omen. Methods. Males (n = 85) and females (n = 76) between the ages of 19 and 95 years were administered the University of Pennsylvania Smel l identification Test (SIT) over a 3-year span as part of the oral phy siology component of the Baltimore Longitudinal Study of Aging. A line ar mixed-effects regression model was used to determine how longitudin al changes in SIT scores differ with respect to gender, history of med ical problems, and use of prescription medications. Results. Over the 3-year period, SIT scores diminished progressively with increased age. Women and men in the eighth decade of life experienced a decline of g reater than one SIT point per year. Females consistently performed bet ter than males in smell identification. Similar results were obtained regardless of medical problems or medication usage. Conclusions. These results extend the conclusions of previous cross-sectional olfactory studies and indicate that smell identification deteriorates progressiv ely with greater age. Furthermore, age-related declines in olfaction o ccur even in the absence of overt medical problems.