Background

Severe obesity is associated with a low-grade chronic inflammation, and high-sensitivity C-reactive protein (hs-CRP) is a marker that can be used to evaluate chronic inflammation status. Metabolic bariatric surgery (MBS) is shown to decrease hs-CRP level, but long-term results are scarce, and association with weight loss outcomes is undetermined. This study aims to evaluate chronic inflammation in patients with obesity using hs-CRP, and its association with long-term weight loss outcomes after laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB).

Methods

The long-term follow-up data of SLEEVEPASS (ClinicalTrials.gov NCT00793143) randomized clinical trial (RCT) was used. Hs-CRP was measured at baseline, and at 6 months, 1, 3, 5, 7, and 10 years after surgery, and the association with weight and weight loss outcomes were analyzed.

Results

Hs-CRP at baseline was available for 59 out of 240 (24.6%) patients. In the whole study population, the nadir hs-CRP (mean estimate 1.14 mg/ml, 95% CI 0.87-1.49) was achieved at 3 years after surgery with a statistically significant difference to baseline (p = 0.003). No statistically significant difference was seen between LSG and LRYGB in hs-CRP change over time (operation*time interaction p = 0.540). Higher hs-CRP correlated with higher BMI at baseline (Spearman correlation 0.282, p = 0.030) and at 10 years (Spearman correlation 0.490, p = 0.001). At 10 years, a greater percentage total weight loss (%TWL) correlated with lower hs-CRP level (Spearman correlation - 0.558, p < 0.001). Baseline hs-CRP (Spearman correlation - 0.152, p = 0.299) and hs-CRP change in first 6 months postoperatively (Spearman correlation 0.167, p = 0.254) did not correlate statistically significantly with %TWL at 10 years.

Conclusions

MBS decreases hs-CRP also at long-term follow-up with weight loss as the driving force. Neither baseline hs-CRP nor hs-CRP change at 6 months were feasible as a predictive marker for long-term outcomes.