Clinical Interventions in Aging (Aug 2014)
The LIFE Cognition Study: design and baseline characteristics
Abstract
Kaycee M Sink,1 Mark A Espeland,2 Julia Rushing,2 Cynthia M Castro,3 Timothy S Church,4 Ronald Cohen,5 Thomas M Gill,6 Leora Henkin,2 Janine M Jennings,7 Diana R Kerwin,8 Todd M Manini,5 Valerie Myers,9 Marco Pahor,5 Kieran F Reid,10 Nancy Woolard,1 Stephen R Rapp,11 Jeff D Williamson1 On behalf of LIFE Investigators 1Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Sticht Center on Aging, Wake Forest School of Medicine, Winston-Salem, NC, USA; 2Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC, USA; 3Stanford Prevention Research Center, Stanford University School of Medicine, Stanford, CA, USA; 4Pennington Biomedical, Louisiana State University, Baton Rouge, LA, USA; 5Institute on Aging and Department of Aging and Geriatric Research, University of Florida, Gainesville, FL, USA; 6Yale School of Medicine, Department of Internal Medicine, New Haven, CT, USA; 7Department of Psychology, Wake Forest University, Winston-Salem, NC, USA; 8Texas Alzheimer’s and Memory Disorders, Texas Health Presbyterian Hospital Dallas, TX, USA; 9Klein Buendel, Inc., Golden, CO, USA; 10Nutrition, Exercise Physiology and Sarcopenia Laboratory, Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA; 11Department of Psychiatry and Behavioral Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA Abstract: Observational studies have shown beneficial relationships between exercise and cognitive function. Some clinical trials have also demonstrated improvements in cognitive function in response to moderate–high intensity aerobic exercise; however, these have been limited by relatively small sample sizes and short durations. The Lifestyle Interventions and Independence for Elders (LIFE) Study is the largest and longest randomized controlled clinical trial of physical activity with cognitive outcomes, in older sedentary adults at increased risk for incident mobility disability. One LIFE Study objective is to evaluate the effects of a structured physical activity program on changes in cognitive function and incident all-cause mild cognitive impairment or dementia. Here, we present the design and baseline cognitive data. At baseline, participants completed the modified Mini Mental Status Examination, Hopkins Verbal Learning Test, Digit Symbol Coding, Modified Rey–Osterrieth Complex Figure, and a computerized battery, selected to be sensitive to changes in speed of processing and executive functioning. During follow up, participants completed the same battery, along with the Category Fluency for Animals, Boston Naming, and Trail Making tests. The description of the mild cognitive impairment/dementia adjudication process is presented here. Participants with worse baseline Short Physical Performance Battery scores (prespecified at ≤7) had significantly lower median cognitive test scores compared with those having scores of 8 or 9 with modified Mini Mental Status Examination score of 91 versus (vs) 93, Hopkins Verbal Learning Test delayed recall score of 7.4 vs 7.9, and Digit Symbol Coding score of 45 vs 48, respectively (all P<0.001). The LIFE Study will contribute important information on the effects of a structured physical activity program on cognitive outcomes in sedentary older adults at particular risk for mobility impairment. In addition to its importance in the area of prevention of cognitive decline, the LIFE Study will also likely serve as a model for exercise and other behavioral intervention trials in older adults. Keywords: exercise, physical activity, older adults, dementia