Adherence-related factors associated with weight reduction: clinical outcomes of telerehabilitation in patients with metabolic syndrome

Background Metabolic syndrome (MetS) is a major contributor to cardiovascular morbidity, yet our healthcare system is underdeveloped in terms of effective lifestyle interventions. Telemedicine-based programs may offer a scalable option, but evidence on their effectiveness in MetS populations is limited. Objective To evaluate a combined telemedicine-supported lifestyle program compared to non-randomized controls in adults with MetS and identify adherence-related factors associated with weight loss. Methods In this prospective, non-randomized controlled intervention study (2021–2023, Hungary), 133 adults with MetS were enrolled and 111 completed a 90-day lifestyle program. All participants received an initial dietetic consultation; the intervention group additionally used smartphone-based dietary logging, remote exercise monitoring, and biweekly teleconsultations with dietitians and physiotherapists. Primary outcome was waist circumference at the standardized day-90 follow-up; secondary outcomes included body weight, body composition, exercise capacity, metabolic parameters, and adherence indicators. Outcomes were analyzed by baseline-, age-, and sex-adjusted ANCOVA with HC3-robust standard errors; the primary model included a group-by-baseline waist circumference interaction, and exploratory adherence analyses assessed linear trends across ordered weight-loss subgroups. Results A significant group-by-baseline waist circumference interaction was observed ( p = 0.029), with a greater adjusted intervention–control difference at higher baseline waist circumference. The intervention group also showed descriptive reductions in body weight (–5.23 ± 5.16 kg), BMI, skinfold thicknesses, body fat mass, and visceral fat. HbA1c declined by 0.41 ± 0.60 percentage points ( p < 0.001), and HDL-cholesterol increased significantly, while other laboratory parameters changed modestly. After Benjamini–Hochberg adjustment within the respective outcome families, the adjusted between-group differences in abdominal circumference, HbA1c, and skeletal muscle mass remained statistically significant. Exploratory adherence analyses showed significant trends toward more frequent body-weight logging and lower relative energy intake with greater weight loss, but not for the other adherence measures. Conclusions A telemedical lifestyle program was associated with favorable short-term changes in abdominal obesity, body composition, and metabolic control in adults with MetS, although skeletal muscle mass loss was also observed. Regular self-weighing and maintaining a lower relative energy intake were associated with greater weight loss. Telemedicine-supported lifestyle management may represent a promising approach for MetS care.