Effectiveness of a School Physician-Led Counseling Intervention on Cholesterol Levels and Lifestyle Behaviors in Children with Hypercholesterolemia: A Randomized Controlled Trial

Background: This randomized controlled trial aimed to evaluate the effects of a school physician-led counseling intervention on total cholesterol (TC) levels, adherence to the Mediterranean diet, physical activity, and sedentary behavior in children aged 6–7 years with elevated cholesterol levels in a Mediterranean setting. Methods: A one-year randomized controlled study was conducted among children aged 6–7 years with elevated TC levels, excluding those with familial hypercholesterolemia (FH). Participants were randomly assigned to either a control group (n = 38) or an intervention group (n = 39). All participants received standard care consisting of educational materials and baseline counseling, while the intervention group additionally participated in three structured follow-up counseling sessions conducted by school physicians during the one-year study period. Counseling focused on Mediterranean dietary habits, implementation of basic dietary principles in cases of elevated TC levels, promotion of physical activity, and reduction in sedentary behavior. TC levels were measured at baseline and at the end of the study. Dietary habits, physical activity, and sedentary behavior were assessed using validated questionnaires. For the primary outcome, a descriptive change-from-baseline analysis, unadjusted mean difference, the approximate 95% confidence interval, and Cohen’s d effect size were calculated. Results: At baseline, no significant differences in TC levels were observed between groups (p = 0.852). After the intervention, mean TC levels were lower in the intervention group than in the control group (4.977 ± 0.414 mmol/L vs. 5.137 ± 0.410 mmol/L); however, the between-group difference did not reach statistical significance (p = 0.089). The unadjusted mean difference at follow-up was −0.160 mmol/L, with an approximate 95% confidence interval from −0.35 to 0.03 and a small-to-moderate effect size in favor of the intervention group (Cohen’s d = −0.39). Descriptive change-from-baseline analysis showed a greater mean reduction in TC in the intervention group than in the control group (−0.364 mmol/L vs. −0.195 mmol/L). A statistically significant improvement in adherence to the Mediterranean diet was observed in the intervention group compared with the control group (p < 0.001). Favorable changes were also observed in several physical activity and sedentary behavior variables, including participation in organized physical activity, walking and running activities, and reduced television viewing and video gaming time. Given the exploratory nature of behavioral analyses and the number of physical activity and sedentary behavior outcomes examined, these findings should be interpreted cautiously. Conclusions: The school physician-led counseling intervention did not result in a statistically significant between-group difference in TC levels after one year, although the direction and magnitude of change favored the intervention group. The intervention was associated with improved adherence to the Mediterranean diet and favorable exploratory lifestyle-related behavioral changes. Nevertheless, the findings should be interpreted cautiously in light of the relatively small sample size, non-significant primary outcome, and exploratory nature of behavioral analyses.