Lower prevalence of metabolic syndrome and its components in the prediagnostic phase of Parkinson's disease.

Investigating the association between metabolic syndrome (MetS) and all its components with prediagnostic Parkinson's disease (PD) may clarify PD pathogenesis and identify candidates for prevention strategies and neuroprotective trials. We conducted a retrospective study of 890 PD patients diagnosed during 2000-2020 and 8,100 matched controls, analyzing electronic health records up to 15 years before PD diagnosis. Prevalence was assessed annually to track changes in association strength over time. PD patients consistently showed lower MetS prevalence (OR = 0.57-0.8). Compared to controls, PD patients had lower triglycerides (OR = 0.44-0.75), BMI (OR = 0.54-0.65), and hyperglycemia (OR = 0.81-0.86) rates, and females showed higher high-density lipoprotein (HDL) (OR = 1.48-1.82), lower low-density lipoprotein/HDL ratio (OR = 0.46-0.64), and reduced hypertension (OR = 0.79-0.85). These findings suggest an inverse association between MetS and PD years before diagnosis. We propose a lipid-blood pressure index incorporating triglycerides, HDL, and hypertension as a potential clinical tool for PD risk stratification.