Associations between Exposure to Perfluoroalkyl Substances with Subsequent Body Composition and Glycemic Responses to Bariatric Surgery

Per- and polyfluoroalkyl substances (PFAS) are chemicals linked to obesity and metabolic dysfunction, but their role in bariatric surgery remains poorly understood. This prospective pilot study examined correlations between plasma PFAS concentrations, body composition, and glycemic measures in adults undergoing bariatric surgery. Thirty-two patients (91% female; 66% Black; mean age 43 years) were enrolled preoperatively; twenty-two completed follow-up at a mean 8.6 months post-surgery. Three PFAS (PFHxS, PFNA, and PFOS) were quantified by plasma liquid chromatography-mass spectrometry; body composition and insulin sensitivity were assessed by dual-energy X-ray absorptiometry and intravenous glucose tolerance testing. At baseline, higher plasma PFNA and PFOS concentrations tracked with lower total lean mass (ρs = -0.46 and -0.48, respectively) and lean mass index (ρs = -0.46 and -0.42), and PFNA was inversely correlated with body weight (ρs = -0.40). No baseline associations were observed with adiposity or glycemic indices. Postoperatively, PFHxS concentrations decreased (median = -1.103 ng/mL, p < 0.001), whereas PFNA and PFOS did not change. Average PFNA was positively correlated with postoperative changes in HOMA-IR (ρs = 0.51) and total lean mass (ρs = 0.49). No significant associations were observed for average PFHxS or PFOS. These findings suggest that PFNA and PFOS may be linked to reduced lean tissue at baseline, and that PFNA burden modestly tracks with attenuated metabolic and body composition recovery. In an ANCOVA, baseline PFNA was not significantly associated with postoperative HOMA-IR or total lean mass. Larger, longitudinal studies are needed to clarify how PFAS influence these associations.