Individuals with type 2 diabetes mellitus show an increased rate of subsequent Parkinson disease, particularly younger individuals and those with diabetes complications; this association may be related to disrupted shared pathogenic pathways and/or genetic predisposition, according to a study published in Neurology.
This retrospective cohort study utilized mortality data from January 1999 to December 2011 and data from Hospital Episode Statistics (HES), which incorporates all episodes of day-case or inpatient care in England’s National Health Service hospitals.
Using the HES data, 2,017,115 individuals were included in the type 2 diabetes cohort, and 6,173,208 individuals without a coded diagnosis of type 2 diabetes were included in the reference cohort.
Individuals were excluded from both cohorts if they had a record of Parkinson disease dated before or at the same time as their initial admission for type 2 diabetes or their reference condition. To estimate the risk for Parkinson disease diagnosis subsequent to type 2 diabetes, multivariable Cox hazard regression models were used.
Data analysis found a higher rate of subsequent Parkinson disease for subjects with type 2 diabetes, with subgroup analysis showing a substantial increase in rates of Parkinson disease for younger individuals. Among individuals aged 25 to 44, 58 of 130,728 subsequently developed Parkinson disease compared with 280 of 2,559,693 subjects in the reference cohort. Individuals with complicated type 2 diabetes also showed a greater relative increase in risk of Parkinson disease (HR 1.49; 95% CI, 1.42–1.56).
The study investigators conclude, “[this] national record-linkage cohort study suggests an increased risk of [Parkinson disease] in patients with [type 2 diabetes]. Our results support the link between these 2 conditions, which may be the result of genetic predisposition and/or disrupted shared pathogenic pathways with potential clinical and therapeutic implications.”
De Pablo-Fernandez E, Goldacre R, Pakpoor J, Noyce AJ, Warner TT. Association between diabetes and subsequent Parkinson disease: a record-linkage cohort study [published online June 13, 2018]. Neurology. doi:10.1212/WNL.0000000000005771