Comparison of orlistat and sibutramine in an obesity management program: Efficacy, compliance, and weight regain after noncompliance

Abstract

To describe the comparative efficacy of orlistat and sibutramine in an obesity management program, with specific attention to compliance and weight regains after noncompliance. We prospectively evaluated 182 obese patients who were randomized to treatment with orlistat (n=98) or sibutramine (n=84) along with the diet and exercise prescriptions. Compliance (or compliant patient) was defined as adherence to scheduled visit times (at 3-month intervals) and following the prescribed drug regimen. A telephone survey was conducted in case of noncompliance. Significant body weights improvements were seen in both treatment groups. Patients lost a mean of 7.6±2.8% and 10.5±2.9% of initial body weights after a mean drug use of 8.8±5.7 and 8.3±3.7 months in the orlistat and sibutramine groups, respectively (p<0.05 vs. initial body weight). Patients in the sibutramine group lost more weight than the orlistat group (p<0.05). A total of 102 patients (56%) were compliant (53.1% in the orlistat group and 59.5% in the sibutramine group). Factors associated with compliance included weight reduction of more than 5% in the first 3 months and adherence to physical activity. Higher initial body weight, prior anti-obesity therapy, number of concurrent medications, and comorbidity were associated with noncompliance. Weight regains in noncompliant patient were a mean of 5.2±5.1 kg after a mean period of 9.2±4.2 months in the orlistat group, and a mean of 6.1±3.8 kg after a mean period of 9.1±3.9 months in the sibutramine group (p<0.05 vs. last visit for both groups, p>0.05 between groups). Both drugs in an obesity management program can achieve substantial weight loss. However, noncompliance and rebound weight regain after noncompliance are considerable problems.