Patients with prodromal Parkinson’s may have motor impairment 3 years before diagnosis

Individuals with prodromal or unrecognized Parkinson’s disease may have greater impairment involving mobility and strength up to 3 years prior to diagnosis, researchers reported in JAMA Neurology.

While many studies have assessed risk markers for PD, few have characterized functional status of prodromal PD, Cameron Miller-Patterson, MD, MS, of the University of Pennsylvania Perelman School of Medicine, and colleagues wrote.

Miller-Patterson and colleagues sought to evaluate whether functional limitations exist in those with PD prior to a diagnosis, compared with the general population.

The authors conducted a case-control study that used Medicare-linked data from the National Health and Aging Trends Study for a random subsample of individuals aged 65 years and older. Patients with incident PD were defined as having two or more Medicare diagnoses. Controls were defined as those with Medicare eligibility at baseline and 2 or more years prior, with no diagnosis.

Researchers analyzed participant responses to survey questions about dexterity, eating, mobility, mood, pain, sleep, speech, strength and vision.

A total of 6,674 participants were included in the two cohorts. The median age groups were 75 to 79 years and 80 to 84 years, and the percentage of women varied from 48.21% in the Parkinson’s group to 59.98% in the control group.

Individuals with prodromal PD were less likely to report being able to walk six blocks (OR = 0.34; 95% CI, 0.15-0.82), stand independently from a kneeling position (OR = 0.3; 95% CI, 0.11-0.85) or lift a heavy object above their head (OR = 0.36; 95% CI, 0.15-0.87) 3 years prior to diagnosis. In addition, they were more likely to report imbalance (OR = 2.77; 95% CI, 1.24-6.2).

“Individuals with [prodromal PD] may have greater motor dysfunction at least 3 years before diagnosis compared with the general population,” Miller-Patterson and colleagues wrote. “Earlier identification of disease may be important not only for initiating symptomatic intervention but also for identifying populations for neuroprotective studies.”

In a related editorial, Ian O. Bledsoe, MD, MS, of the Weill Institute for Neuroscience at the University of California, San Francisco, and colleagues wrote that there is a potential opportunity to better serve individuals with signs of functional decline before they are diagnosed with PD.

“In some cases, this may mean earlier intervention and in others having a lower threshold for neurological referral,” Bledsoe and colleagues wrote. “It may also mean a lower threshold for specific recommendations, including physical therapy or exercise, given their clear symptomatic benefit to those with PD.”

In addition, Bledsoe and colleagues wrote that the study underscores the value of increased research and understanding of prodromal PD.

Reference:

Bledsoe IO, et al. JAMA Neurol. 2022;doi:10.1001/jamaneurol.2022.4157.