Sedentary Behavior Linked to Poorer Attention Skills in Parkinson’s
Sedentary behavior during waking hours is linked to poorer attention spans in people with mild to moderate Parkinson’s disease, a small pilot study in patients reports.
The study, “Sedentary Time is Associated with Worse Attention in Parkinson’s Disease: A Pilot Study,” was published in the Journal of Movement Disorders.
Cognitive problems, such as deficits in memory, impulse control and attention, are known symptoms of Parkinson’s.
Various studies have shown that moderate to vigorous activity can ease these disease symptoms, much as they aid cognitive health in people without Parkinson’s. But prior studies have not characterized how sedentary behavior associates with cognitive difficulties.
Researchers at the University of Pittsburgh used armband accelerometers and neuropsychological tests to obtain objective and subjective measures of physical activity in 17 people with mild-to-moderate Parkinson’s, all on stable medication and between the ages of 50 and 80 (average age, 65).
Participants’ physical activity was measured for seven to 10 days using the Sensewear Pro armband, which uses an algorithm to collect information on the number of calories burned, as well as sleep quality and states of activity (such as walking, driving, or sitting).
Cognitive skills were measured using the Parkinson’s Disease-Cognitive Rating Scale (PD-CRS), which assesses memory, working memory, verbal fluency, and attention.
Participants also completed a computerized task-switching program to measure cognitive flexibility. This consisted of being shown a single number — one to nine, excluding five — surrounded by either a circle or a square. When surrounded by a circle, they were asked to indicate whether the number was odd or even. When a square, they had to tell whether the number was greater or lesser than five.
Tests using this task were given repeatedly, with each being either identical to or different from a previous test. The difference in reaction time between identical and differing tests (task-switching) provided a measure of a person’s cognitive flexibility.
Of all the cognitive skills measured, sedentary behavior associated only with poorer attention scores.
Physical activity has shown benefits in overall cognition, including the areas of task-switching, memory, and attention. If sedentary behavior was simply the opposite of physical activity, the investigators wrote, all those cognitive areas should be expected to decline.
The fact that sedentary behavior appeared to affect attention alone suggests this relationship is different.
“These results suggest that, relative to other aspects of cognition, sedentary behavior may be independently related to attention over and above MVPA [moderate-to-vigorous activity] in individuals” with Parkinson’s, the team wrote.
Possible reasons for this finding include the study’s small size, and the fact that the 17 people taking part were “very inactive,” although without motor symptoms or comorbidities that “precluded their ability to exercise,” the team added.
Still, sedentary behavior was seen to predict attention deficits independent of mild-to-moderate exercise in this study, and merits future studies that focus not only on increasing physical activity but also on the potential contribution of reducing sedentary time.
“In short,” the researchers concluded, “this pilot study points to the need to further study the consequences of sedentary behavior in individuals with [Parkinson’s].”