Development and validation of a scoring system for pre-surgical and early post-surgical prediction of bariatric surgery unsuccess at 2 years

Abstract

Bariatric surgery (BS) is an effective treatment for morbid obesity. However, a simple and easy-to-use tool for the prediction of BS unsuccess is still lacking. Baseline and follow-up data from 300 consecutive patients who underwent BS were retrospectively collected. Supervised regression and machine-learning techniques were used for model development, in which BS unsuccess at 2 years was defined as a percentage of excess-weight-loss (%EWL) < 50%. Model performances were also assessed considering the percentage of total-weight-loss (%TWL) as the reference parameter. Two scoring systems (NAG-score and ENAG-score) were developed. NAG-score, comprising only pre-surgical data, was structured on a 4.5-point-scale (2 points for neck circumference ≥ 44 cm, 1.5 for age ≥ 50 years, and 1 for fasting glucose ≥ 118 mg/dL). ENAG-score, including also early post-operative data, was structured on a 7-point-scale (3 points for %EWL at 6 months ≤ 45%, 1.5 for neck circumference ≥ 44 cm, 1 for age ≥ 50 years, and 1.5 for fasting glucose ≥ 118 mg/dL). A 3-class-clustering was proposed for clinical application. In conclusion, our study proposed two scoring systems for pre-surgical and early post-surgical prediction of 2-year BS weight-loss, which may be useful to guide the pre-operative assessment, the appropriate balance of patients’ expectations, and the post-operative care.

How Good is Stratification and Prediction Model Analysis Between Primary and Revisional Roux-en-Y Gastric Bypass Surgery? A Multi-center Study and Narrative Review

“…Also, multiple SRs found the outcome in weight loss as continuous %EWL what highlights the misconception that outcomes in the PRYGB and RRYGB possibly have poor responses in sufficient effect. The problem is that we do not know from all the other studies on EWL% outcome the ratio of sufficient effect since it is not stratified in the dichotomous outcomes [ 31 , 42 – 45 ], whereby studies define sufficient EWL confirm our findings in both cohorts [ 25 , 46 – 48 ].…”

“…Seven studies (36.8%) were published in 2022 [ 18 – 24 ], five (26.3%) in 2021[ 25 – 29 ], one (5.3%) in 2020 [ 30 ], two (10.5%) in 2017 [ 31 , 32 ], and one each (5.3%) in 2015, 2012, 2009, and 2007 [ 33 – 36 ].…”

“…In total, 15 studies (78.9%) calculated an AUC for the validation, with an unweighted median (min–max) of the AUC of 0.79 (0.599–0.985) [ 18 – 23 , 25 , 26 , 28 – 32 , 34 , 36 ]. The remaining studies used correlation coefficients ( R or R 2 ) for all the variables used [ 24 , 27 , 33 , 35 ].…”

Molecular remodeling of adipose tissue is associated with metabolic recovery after weight loss surgery

“…Herein, having these considerations into account, we have established a potential link between a greater weight loss reduction with a more extensive transcriptomic and methylomic remodeling in SAT, which ultimately may contribute to these metabolic improvements. Similarly, gene expression changes in SAT were strongly associated with the reduction of neck circumference following bariatric surgery, which was previously suggested to be a reliable predictor of remission rates [ 46 ].…”

“…In this view, %TWL was used in the present study as the main weight loss outcome. Neck circumference, recently reported as a reliable predictor for the success of bariatric surgery [ 46 ], was also measured preoperatively and 12 months following the surgery.…”