Physical Inactivity Caused by Anxiety Linked to Cognitive Impairment

The more anxiety a person feels early in the course of Parkinson’s disease, the less likely that person will stay physically active, which correlates with cognitive impairment.

The study with that finding, “Physical activity as a mediator of anxiety and cognitive functioning in Parkinson’s disease,” was published in Mental Health and Physical Activity.

People with Parkinson’s often report feeling anxiety. Their symptoms, such as dizziness, tremors, and difficulty concentrating, overlap with those of Parkinson’s itself, complicating an accurate diagnosis of anxiety.

At the same time, individuals with Parkinson’s experience a higher risk of cognitive decline than the general population.

Although some studies have related more severe anxiety to a greater risk of cognitive decline, not all studies corroborate that finding, leaving it unclear exactly how one condition might influence the other.

Physical activity has emerged as one factor that might link the two; its anti-anxiety effects have been associated with cognitive activity and dopamine availability.

The possibility that physical activity might connect anxiety to cognitive decline led researchers from California State University at San Bernardino to investigate this possible relationship by tracking anxiety, physical activity, and cognitive performance among 487 individuals newly diagnosed with Parkinson’s over a five-year period.

They found that patients who grew more anxious over the study period experienced cognitive decline and performed worse on cognitive tests, such as the Letter-Number Sequencing task and the Symbol-Digit Modalities Test.

People who reported increasing anxiety also grew less active at home, as measured by the Physical Activity Scale for the Elderly, which was administered routinely during years two through five.

More severe anxiety was associated with worse cognitive decline, and with less leisure and household activity. Cognitive performance, by itself, did not correlate with either leisure or household activity.

Based on these findings, the researchers determined that physical inactivity might underly the connection between anxiety and cognitive impairment. In particular, reductions in physical activity within the first five years from Parkinson’s onset appear detrimental to mental health.

Although physical inactivity is likely not the only consequence of anxiety that contributes to cognitive decline, the study’s results suggest it could be an important factor.

“Decreased participation in physical activities, particularly inactivity within the household,” they concluded, “may play a role in anxiety and cognitive impairment. Future studies are needed to determine the clinical utility of interventions promoting routine physical activity.”