Older Adults with Dementia Are Sedentary for Most of the Day

Abstract

Purpose: Self-reported data suggest that older adults with dementia are inactive. The purpose of the present study was to objectively assess the physical activity (PA) levels of community-dwelling and institutionalized ambulatory patients with dementia, and to compare with the PA levels of cognitive healthy older adults.

Methods: We used actigraphy to assess the PA levels in institutionalized (n = 83, age: 83.0 ± 7.6, Mini-Mental-State Examination (MMSE): 15.5 ± 6.5) and community-dwelling dementia patients (n = 37, age: 77.3 ± 5.6, MMSE-score: 20.8 ± 4.8), and healthy older adults (n = 26, age: 79.5 ± 5.6, MMSE-score: 28.2 ± 1.6). We characterized PA levels based on the raw data and classified <100 counts/min as sedentary behavior.

Results: Institutionalized dementia patients had the lowest daily PA levels (1.69 ± 1.33 counts/day), spent 72.1% of the day sedentary, and were most active between 8:00 and 9:00 am. Institutionalized vs. community-dwelling dementia patients had 23.5% lower daily PA levels (difference M = 0.52, p = .004) and spent 9.3% longer in sedentariness (difference M = 1.47, p = .032). Community-dwelling dementia patients spent 66.0% of the day sedentary and were most active between 9:00 to 10:00 am with a second peak between 14:00 to 15:00. Community-dwelling dementia patients vs healthy older adults' daily PA levels and sedentary time were 21.6% lower and 8.9% longer, respectively (difference M = 0.61, p = .007; difference M = 1.29, p = .078).

Conclusions: Institutionalized and community-dwelling dementia patients are sedentary for most of the day and the little PA they perform is of lower intensity compared to their healthy peers. Their highest PA peak is when they get out of bed in the morning. In addition, it seems that institutionalized living is associated with lower PA levels in dementia patients. These are the first results that objectively characterize institutionalized as well as community-dwelling dementia patients' PA levels and confirm that dementia patients are inactive.

Fig 1. Daily physical activity (PA) pattern in older adults with and without dementia.

The figure shows the hourly PA during the day based on minute-averaged data, starting at midnight (0). The first bars show the hourly mean counts/minute from 0:00 to 1:00 h. Filled bars: dementia patients living in an institution. Open bars: community-dwelling dementia patients. Gray bars: community-dwelling healthy older adults. Values are mean (and standard deviation). *, different to community-dwelling dementia patients (p < 0.05).

Fig 2. Quantity of physical activity (PA) as inferred from the time spent in specific activity count zones.

PA counts were binned in units of 100 counts. The first bars show the daily hours spent in sedentary time (0–99 counts). Note the axis interruption that highlights the large number of hours spent in sedentary time vs. other activity counts zones. Filled bars: dementia patients living in an institution. Open bars: community-dwelling dementia patients. Gray bars: community-dwelling healthy older adults. Values are mean (and standard deviation). *, different to community-dwelling dementia patients (p < 0.05).