BACKGROUND: There is a high prevalence of metabolic syndrome in Western societies, and it is therefore an example of chronic disease whose follow-up could be enhanced by telemedicine. OBJECTIVE: The objective of this study was to assess the effectiveness of a telemedicine programme for the follow-up and control of patients with metabolic syndrome in a primary-care setting. METHODS: Semi-experimental study in which 82 patients with metabolic syndrome were included in a telemedicine programme and compared to 82 patients routinely followed up at health-care facilities. The programme consisted of the teletransmission of analytical parameters via the PITES technological platform for chronic and dependent patients. Other study variables were lifestyle, treatment compliance, perceived health status and satisfaction with the programme. RESULTS: Follow-up showed that 68 patients (82.9%) continued in the programme after 6 months and 45 (54.9%) after one year, with a mean stay of 39.7 weeks. Comparison of the parameters obtained for the telemedicine and control-group patients indicated that the former registered significantly lower mean values for systolic blood pressure (125.5 ± 10.6 SD vs. 136.7 ± 12.0 SD), diastolic blood pressure (81.0 ± 6.3 SD vs. 84.0 ± 6.8 SD), total cholesterol (177.4 ± 34.5 SD vs. 202.4 ± 31.7 SD) and cLDL (106.0 ± 28.1 SD vs. 121.3 ± 30.6 SD). By the end of follow-up, the health status scores of the patients monitored by telemedicine had risen significantly (69.2 vs. 64.2; p = 0.04), and 86.6% stated that they were satisfied. CONCLUSIONS: Telemedicine allows for better control of some of the defining parameters of metabolic syndrome than is achieved by routine clinical practice. Teletransmission is viable and satisfactory, and constitutes a novel contribution to the clinical management of these patients.