Treatment of obesity with intragastric injection of botulinum toxin. Is it worth the pinch? An overview of systematic reviews and meta-analysis.

[BACKGROUND AND AIMS] Αvaialble evidence regarding the effectiveness of intragastric injection of botulinum toxin in reducing anthropometric indices of subjects with obesity is conflicting. We evaluated the existing evidence and perform a meta-analysis to assess the efficacy of intragastric botulinum toxin in treating obesity.

[METHODS] We identified published systematic reviews evaluating the efficacy of intragastric injection of botulinum toxin in patients with overweight or obesity and additionally performed a systematic literature search to retrieve randomized controlled trials on this topic. A random-effects meta-analysis was performed to synthesize the existing studies.

[RESULTS] A total of four systematic reviews were included in our overview of systematic reviews and six randomized controlled trials were included in our meta-analysis. Compared to placebo, intragastric injection of botulinum toxin was ineffective in reducing body weight and body mass index after the application of the Knapp-Hartung adjustment (MD = -2.41 kg, 95%CI = -5.21 to 0.38, I =59% and MD = -1.43 kg/m, 95%CI = -3.04 to 0.18, I =62%, respectively). Moreover, treatment with intragastric injection with botulinum toxin was not superior to placebo in decreasing waist and hip circumference.

[CONCLUSIONS] Based on the available evidence, intragastric injection with botulinum toxin is an ineffective procedure in reducing body weight and body mass index when the Knapp-Hartung method was applied.