Hyposmia in Parkinson's Disease: Demographic and Cognitive Associations

Abstract

Background: As is known, hyposmia is one of the most common prodromal nonmotor features of Parkinson's disease (PD). Objectives: This study investigates the relationship between hyposmia and cognitive status in patients with Parkinson's disease. Methods: Data from 54 Parkinson's disease patients were analyzed, focusing on 20 individuals reporting impaired olfactory function. Patients with conditions such as nasal polyps, allergies, and colds, as well as those with hormonal imbalances, were excluded from the study. The sense of smell was assessed using everyday odor items from the Sniffin' Sticks Test (SST-12). Cognition was evaluated by the Mini-Mental State Examination (MMSE). Demographic parameters, including age, sex, ethnicity, and cognitive data, were investigated in all patients. Statistical comparisons and correlation analyses were conducted using SPSS-21 (IBM SPSS Statistics, Armonk, NY). Results: Patients with hyposmia had a mean age of 64.8 (4.4 SD) years, significantly higher than the mean age of 58.2 (3.2 SD) years in patients without hyposmia (p < 0.05). MMSE scores were lower in the hyposmic group (mean: 21.1 (2.2 SD)) compared to non-hyposmic patients (mean: 26.6 (1.4 SD), p < 0.05). A significant negative correlation (r = -0.47) was found between age and MMSE scores in the hyposmic cohort. Males comprised 55.0% of the hyposmic group. Conclusions: According to the above research in Parkinson's disease patients, hyposmia correlates with older age and lower MMSE scores, emphasizing its potential role as an indicator of expected cognitive dysfunction. Further investigations in this direction are required.