Metabolic Syndrome Correlates with Increased Risk of Parkinson's Disease
Metabolic syndrome is a consequence of excess fat tissue, being overweight. It is the precursor to type 2 diabetes, and produces the same sort of harmful contributions to age-related conditions via increased chronic inflammation and a range of other mechanisms relating to the disruption of normal metabolism. It should not be surprising to see that metabolic syndrome increases the risk of a neurodegenerative condition like Parkinson's disease, as this class of age-related conditions are well known to involve inflammation in brain tissue.
Metabolic syndrome is defined as having three or more of the following risk factors: excess belly fat, high blood pressure, high blood sugar, higher than normal triglycerides, which are a type of fat found in the blood, and low high-density lipoprotein (HDL) cholesterol, or "good" cholesterol. The study involved 467,200 people with an average age of 57; of those 38% had metabolic syndrome. The participants were followed for a median of 15 years. During that time, 3,222 people developed Parkinson's disease. For people without metabolic syndrome, the incidence rate for Parkinson's was 4.87 cases per 10,000 person-years, compared to 5.21 cases per 10,000 person-years for people who had metabolic syndrome. Person-years represent both the number of people in the study and the amount of time each person spends in the study.
After adjusting for age, smoking status, physical activity, and genes that increase the risk of Parkinson's disease, researchers found that people with metabolic syndrome were about 40% more likely to develop Parkinson's disease than people without the syndrome. The researchers also conducted a meta-analysis of all studies on this topic and confirmed the finding that people with metabolic syndrome have an increased risk of Parkinson's disease. Combining the current study with eight previous studies, the researchers found that people with metabolic syndrome were 29% more likely to develop Parkinson's disease than people without the syndrome.