Sense of Smell and Parkinson’s Disease: A Decreased Sense of Smell Indicates Potentially Developing PD
Recent studies proved that a decreased ability to identify strong smells. Such as cinnamon, lemon, gasoline, and onion may indicate getting Parkinson’s disease in the future 10 years before any other symptoms appear. Wherein The Brief Smell Identification Test (BSIT) revealed that people who got low scores in this test have a higher chance of developing PD. For this test, people smell 12 different odors, including lemon, onion, cinnamon, and gasoline. Then divide into 4 groups according to their olfactory function, whether weak, average, or excellent.
Studies That Link the Sense of Smell with Parkinson’s Disease
The study was conducted on approximately 1510 Caucasians and 952 Americans with an average age of 75 years old, and they were monitored for 10 years. Researchers discovered that people with a weak sense of smell are susceptible to PD 5 times more than people with higher ability. The group with a weak sense of smell had 26 cases, and the group with an average sense of smell had 9 cases. While the group with an excellent sense of smell had 7. And researchers indicated that discovering the weak sense of smell eventually helps to identify the population groups that are at risk of developing PD. In addition to the progression of the disease.
Factors That Impact the Sense of Smell
The study also indicated other factors that increase the risk of Parkinson’s disease (Shaking Palsy). Black patients would more probably have a weak sense of smell compared to white patients. However, they had a lower chance of developing PD. The link between a decreased sense of smell and PD was more prominent in men than in women. And although researchers affirmed the necessity of more studies regarding olfactory test use in diagnosing people with PD, this is still a significant step forward. The olfactory test predicted PD only within 4 -5 years.
Time is a critical factor in diagnosing Parkinson’s disease before the symptoms appear, for it may take decades. And by the time of the clinical diagnosis, it would be too late to halt or slow down PD. It is worth mentioning that there are no lab tests for PD. However, in Australia, a new tool was described to be 93% accurate in predicting the disease before the symptoms appear. The test includes the speed and pressure on the pen while people draw spiral shapes.