Kummer BR, Diaz I, Wu X, et al. - Using claims information from a 5% random sample of Medicare beneficiaries from 2008 to 2015, researchers conducted a retrospective cohort study to ascertain if cerebrovascular risk factors are correlated with subsequent diagnoses of Parkinson disease, and whether these connections are comparable in magnitude to those with subsequent Alzheimer disease diagnoses. Of 1,035,536 Medicare beneficiaries, 15,531 were diagnosed with Parkinson disease and 81,974 were diagnosed with Alzheimer's disease for an average of 5.2 years. Most assessed risk factors for cerebrovascular disease, including previous stroke, were linked to the subsequent diagnosis of Parkinson disease. These associations' magnitudes were comparable to the connections between cerebrovascular risk factors and Alzheimer disease but attenuated. Confirming the analytical model's validity, most cerebrovascular risk factors were not linked to the subsequent renal colic diagnosis. The authors concluded that Parkinson disease is associated with cerebrovascular risk factors, an effect similar to their association with Alzheimer disease.