Weight Change During Early Parkinson Disease May Cause Changes in Thinking Skills  

A clinical study published in Neurology found that people who gain or lose weight soon after being diagnosed with Parkinson disease (PD) may be more likely to have changes in their thinking skills than people who maintain a steady weight.

Those with PD who lost weight had a faster decline in their overall thinking scores compared to those with PD who maintained their weight. Both groups started with average scores of 27 on a thinking skills test. The scores of those who lost weight declined 0.19 points faster per year than those who maintained their weight. 

The thinking skills with the steepest declines were verbal fluency skills, which are a measure of executive function. 

In contrast, the people with PD who gained weight had a slower decline in their scores on a test of processing speed compared with those who maintained their weight. 

“These findings highlight the potential importance of weight management in the early stages of PD,” said Jin-Sun Jun, MD, Kangnam, Sacred Heart Hospital, Republic of Korea. “Further studies are needed to determine whether taking steps to prevent weight loss could slow cognitive decline in people with PD. Early weight loss is a common symptom in people with PD. It could serve as a sign that people are at risk of cognitive decline.”  

The study involved 358 participants who were recently diagnosed with PD and had not yet started taking PD medications. They were an average of 61 years of age and had been diagnosed an average of 2 years earlier. They were compared with 174 other participants who did not have PD.  

Participants took tests of thinking skills at the beginning of the study and then every year for up to 8 years. They also took tests for other nonmotor symptoms that can occur in people with PD, such as depression, anxiety, and sleep disorders. 

Weight gain or loss was defined as a change of more than 3% of body weight during the first year of the study. Weight maintenance was defined as no change or change of no more than 3%.