Impaired attention predicts motor performance decline in older community-dwellers with normal baseline mobility: Results from the Italian Longitudinal Study on Aging (ILSA)

Abstract

Background. Cognitive decline, particularly when executive functions are compromised, may worsen motor performance (MP) decline in the elderly population. We investigated whether a global test, a memory test, and an attention test predicted MP decline in older community-dwellers with normal baseline MP participating in the Italian Longitudinal Study on Aging (ILSA). Methods. One thousand fifty-two ILSA participants (71.2 ± 4.8 years old, mean ± standard deviation [SD], 67% men), with normal baseline MP were reassessed after 3 years using the same MP battery. Participants whose MP score reduction from baseline to follow-up was > 75 percentile were considered to be MP decliners. Global cognition, memory, and attention were assessed using the Mini-Mental State Examination (MMSE), the Babcock Story Recall Test (BSRT), and the Digit Cancellation Test (DCT), respectively. The baseline score on each test was examined as a potential predictor of decline in global MP or in single motor tasks. Results. Baseline scores on the three cognitive tests were worse among the 166 MP decliners, compared with nondecliners. Participants in the lowest quartile of DCT had a > 2-fold higher adjusted risk of declining than did participants in the highest quartile (odds ratio = 2.47, 95% confidence interval, 1.29-4.74). Conversely, MMSE and BSRT scores no longer predicted MP decline after adjustment. Impaired attention strongly predicted the decline in attention-demanding tasks (tandem walking), but also affected routine tasks (walking). Conclusions. Impairment in a test measuring attention predicts MP decline among older community-dwellers with normal baseline MP. This finding is consistent with the hypothesis that attentional and executive dysfunction is a major determinant of mobility disability in elderly persons. Copyright 2007 by The Gerontological Society of America.