Dose-dependent effects of lifestyle interventions on blood lipid levels: Results from the PREMIER trial

Abstract

ObjectiveTo assess the effects of comprehensive lifestyle modification on low-density lipoprotein cholesterol (LDL-C) levels and whether greater participation in counseling sessions was associated with greater LDL-C reductions. MethodsMulticenter trial of Pre- or Stage 1 hypertensive adults randomized to: (1)Advice alone, (2)‘Established’ lifestyle intervention implementing physical activity, sodium reduction, and weight loss, if overweight, or (3)‘Established + DASH’ lifestyle intervention with DASH diet counseling. Both intervention groups received behavioral counseling. We used generalized estimating equations to model the intervention’s effects on lipid outcomes. Analyses of number of sessions and lipids were adjusted for demographics and medical history. ResultsAmong 756 participants (mean age 49.7, 63.2% women, 34.7% black), both lifestyle interventions reduced LDL-C, triglycerides, and total cholesterol (TC) at six months. Compared to the ‘Advice’ arm, net mean lipid changes in the Established group were: LDL-C of -5.6 mg/dL (p=0.001) and TC of -7.3 mg/dL (p<0.001). Similarly, changes in the ‘Established + DASH’ group were: LDL-C of -4.0 mg/dL (p=0.03) and TC of -5.7 mg/dL (p=0.006). In dose-response analyses, for every 10-session increase, LDL-C changed by -6.2 mg/dL (p=0.003). ConclusionsComprehensive lifestyle modification lowers LDL-C with greater benefit among persons who attend more counseling sessions. Practice ImplicationsPatient engagement is a critical aspect of effective lifestyle interventions.