Cardiovascular effects of sibutramine in the treatment of obese adolescents: results of a randomized, double-blind, placebo-controlled study.

BACKGROUND: Adolescent obesity is a major public health problem. Treatment options in addition to behavioral therapy could include pharmacotherapy with sibutramine. OBJECTIVES: Concerns regarding increases in blood pressure and heart rate after sibutramine treatment in some adult patients precipitated the present analysis, which evaluated the cardiovascular safety of sibutramine plus a behavioral therapy program in obese adolescents. PATIENTS AND METHODS: With this 12-month, randomized, double-blind, placebo-controlled trial in 33 US clinics we studied 498 adolescents aged 12 to 16 years with multiethnic backgrounds and BMIs of 28.1 to 46.3 kg/m2. RESULTS: The subjects were randomly assigned to behavioral therapy plus 10 mg of sibutramine or behavioral therapy plus placebo daily. At the end point, there was a mean treatment group difference in BMI of 2.6 kg/m2 in favor of sibutramine. Small mean decreases in blood pressure and pulse rate were seen in both sibutramine and placebo groups at the end point (systolic blood pressure: -2.1 vs -2.1 mmHg; diastolic blood pressure: -0.1 vs -1.1 mmHg; pulse rate: -0.2 vs -1.8 bpm). In both treatment groups, these reductions in vital signs were greater at the end point when BMI reduction was > or = 5% compared with < 5%. CONCLUSIONS: Sibutramine may have some direct cardiovascular effects on obese adolescents. These cardiovascular effects may be balanced by a reduction in BMI, which, in adolescents, seems to be greater than that observed in adults.

Effects of sibutramine treatment in obese adolescents: a randomized trial.

BACKGROUND: Increased prevalence of adolescent obesity requires effective treatment options beyond behavior therapy. OBJECTIVE: To see whether sibutramine reduced weight more than placebo in obese adolescents who were receiving a behavior therapy program. DESIGN: 12-month, 3:1 randomized, double-blind trial conducted from July 2000 to February 2002. SETTING: 33 U.S. outpatient clinics. PARTICIPANTS: 498 participants 12 to 16 years of age with a body mass index (BMI) that was at least 2 units more than the U.S. weighted mean of the 95th percentile based on age and sex, to the upper limit of 44 kg/m2. INTERVENTIONS: Site-specific behavior therapy plus 10 mg of sibutramine or placebo. Blinded study medication dose was uptitrated to 15 mg or placebo at month 6 if initial BMI was not reduced by 10%. MEASUREMENTS: Body mass index, waist circumference, body weight, fasting lipid and glycemic variables, safety, and tolerability. RESULTS: Seventy-six percent of patients in the sibutramine group and 62% of patients in the placebo group completed the study. The estimated mean treatment group difference at month 12 (linear mixed-effects model) favored sibutramine for change from baseline in BMI (-2.9 kg/m2 [95% CI, -3.5 to -2.2 kg/m2]) and body weight (-8.4 kg [CI, -9.7 to -7.2 kg]) (P < 0.001 for both). The sibutramine group had greater improvements in triglyceride levels, high-density lipoprotein cholesterol levels, insulin levels, and insulin sensitivity (P < or = 0.001 for all). The rate of tachycardia was greater with sibutramine vs. placebo (12.5% vs. 6.2%; difference, 6.3 percentage points [CI, 1.0 to 11.7 percentage points]) but did not lead to increased withdrawal (2.4% vs. 1.5%; difference, 0.9 percentage point [CI, -1.7 to 3.5 percentage points]). LIMITATIONS: The 1-year study duration precluded assessment of long-term weight maintenance and putative health benefits and harms, and 24% and 38% of the sibutramine and placebo groups, respectively, did not complete follow-up. CONCLUSIONS: Sibutramine added to a behavior therapy program reduced BMI and body weight more than placebo and improved the profile of several metabolic risk factors in obese adolescents.