Clinical Edge

Summaries of Must-Read Clinical Literature, Guidelines, and FDA Actions

Poor Cognition Linked to Incident Parkinsonism Risk

JAMA Neurol; ePub 2017 Sep 25; Darweesh, et al

Poor cognitive functioning is associated with an increased risk of incident parkinsonism, including probable Parkinson disease (PD), according to a recent study. Furthermore, cognition indicates the probability of parkinsonism over long intervals and extends beyond patients with onset of parkinsonism after dementia. The findings suggest that cognitive dysfunction can be considered a sign of prodromal PD. Baseline cognitive function was assessed in 7,386 participants (57.4% women, mean age 65.3 years) who were free of parkinsonism and dementia. 4 tests were administered (Stroop color word test, letter-digit substitution, verbal fluency, and word learning) and a global cognition score was derived from principal component analysis. Researchers found:

  • During follow-up (median, 8.3 years), 79 (1.1%) individuals received a diagnosis of incident parkinsonism; of these, 57 (72.2%) received a diagnosis of probable PD.
  • Among patients with incident parkinsonism, 24 (30.4%) also developed dementia (10 before and 14 after parkinsonism onset).
  • Poor global cognition at baseline was associated with a higher hazard of incident parkinsonism.
  • The association remained robust beyond the first 8 years and after removing individuals with dementia onset before parkinsonism.


Darweesh SKL, Wolters FJ, Postuma RB, et al. Association between poor cognitive functioning and risk of incident parkinsonism. The Rotterdam Study. [Published online ahead of print September 25, 2017]. JAMA Neurol. doi:10.1001/jamaneurol.2017.2248.

This Week's Must Reads

Possible Link: Hepatic Steatosis and Brain Aging, JAMA Neurol; ePub 2017 Nov 20; Weinstein, et al

Neurologic Drug Shortages May Compromise Care, Neurology; ePub 2017 Nov 15; Omorodion, et al

Sleep Fragmentation Linked with PD in Older Adults, Mov Disord; ePub 2017 Oct 30; Sohail, Yu, et al

Dietary Sodium to Potassium Ratio and Stroke Risk, Stroke; ePub 2017 Oct 10; Willey, Gardener, et al

Sleep Apnea Did Not Accelerate Kidney Decline, Sleep; ePub 2017 Nov 3; Canales, Hagen, et al

Must Reads in Movement Disorders

Cognitive Impairment in PSP Linked with Tau Burden, Mov Disord; ePub 2017 Oct 30; Koga, Parks, et al

Dystonia and Ataxia Progression Examined, Parkinson Relat Disord; ePub 2017 Oct 23; Kuo, et al

Poor Cognition Linked to Incident Parkinsonism Risk, JAMA Neurol; ePub 2017 Sep 25; Darweesh, et al

ET Caregiver Burden, Correlates Examined, Front Neurol; ePub 2017 Aug 14; Morgan, et al

Examining Stepping Capacity in People with PD, J Neurol Phys Ther; 2017 Oct; Duncan, et al