Imaging May Predict Parkinson Disease Progression in Older Adults

A study in Parkinsonism and Related Disorders suggests reduced gray matter integrity may be a key neuroimaging marker for the development of mild parkinsonian signs (MPS), reports Clinical Advisor . A total of 819 subjects who did not use walking assisted devices, could complete a six-minute walking test, and qualified to undergo brain magnetic resonance imaging (MRI) were enlisted between 2006 and 2008. Of these, 315 satisfied eligibility for a 3T MRI, and 205 had complete Unified Parkinson Disease Rating Scale (UPDRS) data at baseline and follow-up, were not on drugs that could induce or inhibit parkinsonism, and were not diagnosed with Parkinson Disease or other neurologic disorders. MPS were present in 62 of 205 participants at the beginning of the study, while the average age of participants was 82.7 years and the mean UPDRS-III score at baseline for was 1.5 plus or minus 2.8. Mean follow-up time was 3.8 plus or minus 0.8 years, and the average rate of UPDRS-III change was 0.6 plus or minus 1.0 points annually for a mean total of 2.29 points. Older age, male sex, and diabetes were associated with a faster rate of UPDRS-III change in those lacking MPS but not those with MPS. The only imaging marker associated with faster UPDRS-III progression among those without MPS was higher gray matter mean diffusivity, while no imaging factors were linked to UPDRS-III change among MPS positive subjects.