Designing clinical trials for assessing the effects of cognitive training and physical activity interventions on cognitive outcomes: The Seniors Health and Activity Research Program Pilot (SHARP-P) Study, a randomized controlled trial

Abstract

BackgroundThe efficacy of non-pharmacological intervention approaches such as physical activity, strength, and cognitive training for improving brain health has not been established. Before definitive trials are mounted, important design questions on participation/adherence, training and interventions effects must be answered to more fully inform a full-scale trial.MethodsSHARP-P was a single-blinded randomized controlled pilot trial of a 4-month physical activity training intervention (PA) and/or cognitive training intervention (CT) in a 2 × 2 factorial design with a health education control condition in 73 community-dwelling persons, aged 70-85 years, who were at risk for cognitive decline but did not have mild cognitive impairment.ResultsIntervention attendance rates were higher in the CT and PACT groups: CT: 96%, PA: 76%, PACT: 90% (p=0.004), the interventions produced marked changes in cognitive and physical performance measures (p≤0.05), and retention rates exceeded 90%. There were no statistically significant differences in 4-month changes in composite scores of cognitive, executive, and episodic memory function among arms. Four-month improvements in the composite measure increased with age among participants assigned to physical activity training but decreased with age for other participants (intervention*age interaction p = 0.01). Depending on the choice of outcome, two-armed full-scale trials may require fewer than 1,000 participants (continuous outcome) or 2,000 participants (categorical outcome).ConclusionsGood levels of participation, adherence, and retention appear to be achievable for participants through age 85 years. Care should be taken to ensure that an attention control condition does not attenuate intervention effects. Depending on the choice of outcome measures, the necessary sample sizes to conduct four-year trials appear to be feasible.Trial RegistrationClinicaltrials.gov Identifier: NCT00688155

Aerobic Exercise Intervention, Cognitive Performance, and Brain Structure: Results from the Physical Influences on Brain in Aging (PHIBRA) Study

“…The CFA displayed good fit indices despite the small sample size, disregarding TS. Previous studies have generally had fewer tasks and/or investigated fewer constructs (Burns et al, 2009; Erickson et al, 2011; Legault et al, 2011; Thomas et al, 2016). Thus, the present observation that aerobic exercise compared to stretching and toning control training was more effective in improving cognition in older adults is an important contribution to a field showing equivocal results, owing at least in part, to a lack of robust test batteries enabling use of latent constructs.…”

“…During the last two decades, numerous investigations have addressed the relationships between physical exercise and cognition (e.g., Khatri et al, 2001; Fabre et al, 2002; Legault et al, 2011; Langlois et al, 2013). Despite the wealth of literature showing how staying physically active may prevent cognitive decline (Yaffe et al, 2001; Sofi et al, 2011), dementia onset (Laurin et al, 2001; Yaffe et al, 2009), and improve brain-behavior relationship throughout the lifespan (Boraxbekk et al, 2016), there are also studies, e.g., a recent Cochrane review (Young et al, 2015), that have concluded that aerobic exercise, compared to active control training, had no added benefit on any cognitive function investigated.…”

Effect of a 24-Month Physical Activity Intervention vs Health Education on Cognitive Outcomes in Sedentary Older Adults

“…7 Two recent small RCTs of physical activity found no benefit of a structured physical activity program vs. no intervention or cognitive training in non-demented older adults with cognitive complaints or at risk of cognitive decline. 10;11 However, a 6-month RCT of a home-based physical activity program vs. usual care in participants with memory complaints or mild cognitive impairment found a modest cognitive benefit. 12 The LIFE Pilot study showed a correlation between changes in physical and cognitive performance in a 12 month exercise trial.…”

A Patient-Centered Analysis of Enrollment and Retention in a Randomized Behavioral Trial of Two Cognitive Rehabilitation Interventions for Mild Cognitive Impairment

“…For example, in a study involving comparison of cognitive training and physical activity or a combination of both, the researchers screened 343 potential subjects in order to enroll just 73 participants, a 21% enrollment rate [20]. Most were excluded as they were ineligible after further screening related to study exclusion criteria, but it appears a portion were also merely unwilling to participate in the research program.…”