The incidence of age-associated cognitive impairment is increasing rapidly and looms as a major clinical and public health issue. Drugs have been developed to treat dementia and compounds have been tested as preventive agents, and while some progress has been made, non-pharmacologic interventions also require study. Evidence from small or uncontrolled studies indicates that physical exercise and cognitive training have considerable promise as prevention strategies, to the extent that they are often recommended, however their efficacy has not been established by an adequately powered randomized clinical trial (RCT). Our goal is to develop and conduct such a well-designed trial to assess whether a multi-factorial intervention involving physical activity and cognitive training reduces the risk of significant cognitive decline in older individuals. We propose in this application to prepare ourselves for this by conducting a pilot study, which will provide the experience and data to assess whether physical activity and cognitive training separately improve executive function and episodic memory over 6 months, to determine whether a combination intervention holds promise beyond individual interventions without compromising adherence, and to design a well-organized and efficient full scale, multi-center RCT. A composite measure based on executive function and episodic memory is chosen as the primary outcome: these components are important markers of cognitive aging and may be most responsive to our interventions. Participants (N=120) will be aged 70-85 yrs. In an effort to identify an at-risk yet not cognitively impaired population we have will select a 'normal' population with mild deficits in Modified Mini-Mental State exam scores who may be appropriate candidates for the full scale RCT. We will screen out individuals with mild cognitive impairment, a pre-dementia transitional state. Participants will be randomly assigned to one of four conditions: an educational control condition, moderate-intensity physical activity training, repetition lag cognitive training, or both physical activity and repetitive lag training. Secondary outcomes will be measures of other cognitive domains, perceived cognitive functioning problems, quality of life, adherence, satisfaction, and fitness. This resubmission represents the collaboration of a team of investigators with extensive expertise in the underlying sciences and technology. To reduce costs, the pilot will be conducted at a single site. The results of a full-scale RCT will answer whether non-pharmacological approaches are effective in preventing significant cognitive decline, fill an important gap in knowledge for practicing evidence-based geriatric medicine, and provide critical context for evaluating future trials of pharmacologic agents.

R01AG029285

2007-09-30

2010-05-31