Project Summary/Abstract The Parent R01 is examining the effects of a behavioral weight loss program as compared to a chronic disease self-management (CDSM) program on weight, physical function, pain, and physical activity among adults after total knee replacement (TKR). The proposed supplemental project aims to add an Alzheimer’s disease and its related dementias (AD/ADRD) focus to our project by examining whether a behavioral weight loss program and physical activity may have a protective effect against AD/ADRD among adults with TKR by sustaining cognition. An increasing number of individuals are undergoing TKR, and although the surgery helps to initially reduce mortality, the majority of deaths in the decades after surgery are from AD/ADRD and cardiovascular disease. Healthcare costs from AD/ADRD are among the highest in the US, placing substantial economic burden on society. Although the reasons for the excess mortality from AD/ADRD among adults with TKR are unknown, strategies are needed to help reduce this population’s high risk for the development of AD/ADRD as well as the corresponding economic burden that this surgery and conditions place on society. The first Aim of the supplement is to examine the preliminary effects of a multicomponent (diet and physical activity) weight loss program as compared to a CDSM control group on cognition at 6 months. The second Aim will examine how changes in diet, aerobic physical activity, and weight are associated with cognition at 6 months. The final Aim is to examine the acute effects of a brief bout of walking on cognition. To examine aims 1 and 2, participants (n=60) will be randomized to one of two 12-month programs: (1) PACE weight loss program or (2) CDSM. Assessments at baseline and 6 months will include measures of cognition, weight, objectively-measured physical activity, and dietary intake. To examine aim 3, a cross-over design will be used at the baseline assessment, in which participants (n=60) will be randomized to either Immediate or Delayed walking conditions. Participants randomized to Immediate will complete the Six-min walking test first, whereas participants randomized to delayed will complete the walking test after a 6-min rest period. A brief cognitive test assessing processing speed will be completed 3 times at the baseline assessment to examine the effect of an acute walking bout on cognition. The expected outcome from this supplemental project is to determine the preliminary effects of changes in weight, aerobic physical activity, and dietary intake on cognition in adults after TKR. If a behavioral weight loss program and/or briefs bouts of activity can sustain cognition among an aging population, the promotion of changes in these lifestyle behaviors could help to prevent or delay the onset of AD/ADRD.

Total knee replacement continues to increase and while the surgery helps to initially reduce mortality, the majority of deaths in the decades after surgery are from Alzheimer’s Disease and its related dementias (AD/ADRD). Strategies are needed to help reduce this populations high risk for the development of AD/ADRD and corresponding economic burden placed on society. The objective of this supplemental project is to expand the focus of the parent R01 to include a focus on AD/ADRD by examining if changes in weight, diet, and activity (acute and over 6 months) influences cognition in adults after knee replacement.