Long-term effects of bariatric surgery in patients with obesity and chromosome 16 p11.2 microdeletion

Abstract Background Chromosome 16 p11.2 microdeletion is associated with early-onset obesity. Information is limited about the effect of bariatric surgery in patients with genetic obesity. Objective To examine the effects of bariatric surgery in obese patients with chromosome 16 p11.2 microdeletion. Setting Academic research institution. Methods The Swedish Obese Subjects study is a prospective study with 2010 participants receiving bariatric surgery. DNA was available for 1843 participants. Multiplex ligation-dependent probe amplification was used to identify 16 p11.2 microdeletion carriers. Follow-up time was 10 years. In carriers and noncarriers, follow-up rate was 86% and 82%, respectively, at 10 years. Results Nine carriers of the chromosome 16 p11.2 microdeletion (9/1843, .49%) were found. At baseline, most risk factors were similar; however, carriers had higher body mass index (BMI), insulin levels, and systolic blood pressure compared to noncarriers. At the 1-year examination, the percent excess BMI lost (%EBMIL) in carriers and noncarriers was 71.9 and 62.2, respectively ; P = .031 (37.9 and 30.6 kg). This was followed by partial weight regain in both groups, and after 10 years %EBMIL was 25.5 and 41.5 (15.7 and 21.3 kg), respectively (P = .377). Changes in risk factors were similar in the carriers and noncarriers. Two carriers who had type 2 diabetes at baseline were both in remission at 2-year follow-up but relapsed at 10-year follow-up. Perceived health status was similar in carriers and noncarriers during follow-up (overall P = .198). Conclusions Despite a small sample size, our results indicate that bariatric surgery is a treatment option for obese patients with chromosome 16 p11.2 microdeletion.