IN a new, nonrandomised controlled trial from the University of Gothenburg, researchers have found that breast cancer risk was lower in individuals that had undergone bariatric surgery. Additionally, baseline insulin levels showed to be a modulator of this risk.
Led by Felipe Kristensson, Sahlgrenska Academy at University of Gothenburg, Sweden, the team conducted a nonrandomised intervention trial, designed to investigate the long-term effects of bariatric surgery on obesity-related mortality and morbidity. The long-term, nonrandomised trial followed 2,867 women, aged 37 to 60 years, for nearly 24 years on average. Participants were divided into two groups: 1,420 women underwent bariatric surgery, while 1,447 women received standard obesity care.
During the follow-up period, 154 breast cancer cases were recorded, with 66 cases in the surgery group and 88 in the control group. The findings revealed that women who underwent bariatric surgery had a 32% lower risk of developing breast cancer compared to those who did not undergo surgery (hazard ratio [HR], 0.68; 95% CI, 0.49–0.94; P = 0.019). The protective effect of surgery was even more pronounced in women with higher baseline insulin levels, where the risk was nearly halved (HR, 0.48; 95% CI, 0.31–0.74; P: 0.001).
This study is one of the first to provide long-term, prospective data on the impact of bariatric surgery on breast cancer risk, highlighting the importance of insulin levels in modulating this risk. The results suggest that bariatric surgery could be an effective intervention for reducing breast cancer risk, particularly in women with obesity and hyperinsulinemia.
Helena Bradbury, EMJ
Reference
Kristensson FM et al. Breast Cancer Risk After Bariatric Surgery and Influence of Insulin Levels: A Nonrandomized Controlled Trial. JAMA Surg. 2024;159(8):856–863.
