Supplementary Material for: Three-year effects of a multidomain lifestyle intervention on impulsivity: Results from a randomized clinical trial

Introduction: Research has consistently shown associations between elevated impulsivity and adverse physical and mental health outcomes. Specifically, impulsivity has been associated with higher body mass index and cardiometabolic issues. However, evidence from randomized clinical trials (RCTs) on whether impulsivity is responsive to a multidomain lifestyle intervention in older adults with overweight or obesity who are at high cardiovascular risk is limited. Methods: Participants from the PREDIMED-Plus-Cognition sub-study, followed for 3 years as part of the PREDIMED-Plus RCT, were included. Eligible participants had overweight or obesity and metabolic syndrome at baseline. Participants were randomly allocated to either an intensive intervention group (IIG), with an energy-restricted Mediterranean diet (MedDiet), physical activity, and behavioral support, or to a control group (CG), advised to follow an ad libitum MedDiet. The primary outcome of the current study was the evaluation of impulsivity, which was only assessed in participants from the PREDIMED-Plus-Cognition sub-study. Trait impulsivity was assessed using the UPPS-P Impulsive Behavior Scale and behavioral impulsivity through 4 neuropsychological evaluations at baseline, 1-year, and 3-year follow-ups. Z-score composites for Global, Trait, and Behavioral Impulsivity were estimated. Multivariate linear mixed models were used to assess the effect of the PREDIMED-Plus intervention on impulsivity among the participants who participated in the PREDIMED-Plus-Cognition sub-study. Results: A total of 306 participants (CG: n=156; IIG: n=150; mean age [SD]: 65.0 [4.7] years; 45.7% female) had impulsivity data at baseline. Compared to the CG, participants in the IIG exhibited decreases in Trait Impulsivity at 1 year (mean z-score change [95%CI]: -0.26 [-0.49, -0.03]), and in Global (-0.28 [-0.52, -0.03]) and Behavioral (-0.28 [-0.54, -0.02]) Impulsivity at 3-year follow-up. Conclusion: An intensive lifestyle intervention combining MedDiet, physical activity, and behavioral support resulted in a long-term reduction of impulsivity among older adults at high cardiometabolic risk. Public health guidelines may consider multidomain lifestyle intervention strategies to decrease impulsivity.