Type 2 diabetes and Parkinson's disease

Copyright © 2019 John Wiley & Sons PRACTICAL DIABETES Vol. 36 No. 4 115 B definition, common conditions commonly occur, and so the occurrence together of two relatively prevalent conditions, type 2 diabetes (T2DM) and Parkinson’s disease (PD), might be considered simply by chance. Although the prevalence of T2DM (5% of UK population) is greater than that of PD (0.2% overall), both conditions increase with age, particularly PD (1% over 60 years; 5% over 85 years). Moreover, each shares some similarity in generally being as of later, slow onset and progressive in nature. As to causation, these two conditions, again, share similar concepts of genetic predisposition interacting with environmental factors in line with current understanding. So, by the laws of probability, it would be expected that these two conditions are likely to arise together in a proportion of either diabetes or Parkinson’s disease clinics. But, when the two occur together, is it indeed a chance observation or is there a more significant association? With this in mind, it should be remembered that an association does not necessarily indicate a causal link in either direction, but it does raise interesting issues to consider in terms of respective relationships between the two conditions.