Very few models predict weight loss among type 2 diabetes mellitus (T2D) patients after laparoscopic sleeve gastrectomy (LSG). This retrospective study undertook such a task.
Materials and Methods:
We identified all patients >18 years old with T2D who underwent primary LSG at our institution and had complete data. The training set comprised 107 patients operated upon during the period April 2011 to June 2014; the validation set comprised 134 patients operated upon during the successive chronological period, July 2014 to December 2015. Sex, age, presurgery BMI, T2D duration, number of T2D medications, insulin use, hypertension, and dyslipidemia were utilized as independent predictors of 1-year BMI. We employed regression analysis, and assessed the goodness of fit and “Residuals versus Fits” plot. Paired sample t-tests compared the observed and predicted BMI at 1 year.
Results:
The model comprised preoperative BMI (β = 0.757, P = 0.026) + age (β = 0.142, P < 0.0001) with adjusted R2 of 0.581 (P < 0.0001), and goodness of fit showed an unbiased model with accurate prediction. The equation was: BMI value 1 year after LSG = 1.777 + 0.614 × presurgery BMI (kg/m2) +0.106 × age (years). For validation, the equation exhibited an adjusted R2 0.550 (P < 0.0001), and the goodness of fit indicated an unbiased model. The BMI predicted by the model fell within −3.78 BMI points to +2.42 points of the observed 1-year BMI. Pairwise difference between the mean 1-year observed and predicted BMI was not significant (−0.41 kg/m2, P = 0.225).
Conclusions:
This predictive model estimates the BMI 1 year after LSG. The model comprises preoperative BMI and age. It allows the forecast of patients' BMI after surgery, hence setting realistic expectations which are critical for patient satisfaction after bariatric surgery. An attainable target motivates the patient to achieve it.
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References
1.
LemanuDP, SinghPP, RahmanH, et al.Five-year results after laparoscopic sleeve gastrectomy: A prospective study. Surg Obes Relat Dis, 2015; 11:518–524.
2.
ViscidoG, GorodnerV, SignoriniFJ, et al.Obese patients with type 2 diabetes: Outcomes after laparoscopic sleeve gastrectomy. J Laparoendosc Adv Surg Tech A, 2019; 29:655–662.
3.
GrahamC, SwitzerN, ResoA, et al.Sleeve gastrectomy and hypertension: A systematic review of long-term outcomes. Surg Endosc, 2019; 33:3001–3007.
4.
BrethauerSA, AminianA, Romero-TalamásH, et al.Can diabetes be surgically cured? Long-term metabolic effects of bariatric surgery in obese patients with type 2 diabetes mellitus. Ann Surg, 2013; 258:628–636; discussion 636–637.
5.
FischerL, HildebrandtC, BrucknerT, et al.Excessive weight loss after sleeve gastrectomy: A systematic review. Obes Surg, 2012; 22:721–731.
6.
BozaC, SalinasJ, SalgadoN, et al.Laparoscopic sleeve gastrectomy as a stand-alone procedure for morbid obesity: Report of 1,000 cases and 3-year follow-up. Obes Surg, 2012; 22:866–871.
7.
MaggardMA, ShugarmanLR, SuttorpM, et al.Meta-analysis: Surgical treatment of obesity. Ann Intern Med, 2005; 142:547–559.
8.
CottamS, CottamD, CottamA, et al.The use of predictive markers for the development of a model to predict weight loss following vertical sleeve gastrectomy. Obes Surg, 2018; 28:3769–3774.
9.
HomanJ, BetzelB, AartsEO, et al.Secondary surgery after sleeve gastrectomy: Roux-en-Y gastric bypass or biliopancreatic diversion with duodenal switch. Surg Obes Relat Dis, 2015; 11:771–777.
10.
AbdulrazzaqS, ElhagW, El AnsariW, et al.Is Revisional gastric bypass as effective as primary gastric bypass for weight loss and improvement of comorbidities?. Obes Surg, 2020; 30:1219–1229.
11.
MasrurM, BustosR, Sanchez-JohnsenL, et al.Factors associated with weight loss after metabolic surgery in a multiethnic sample of 1012 patients. Obes Surg, 2020; 30:975–981.
12.
BindaA, JaworskiP, KudlickaE, et al.The impact of selected factors on parameters of weight loss after sleeve gastrectomy. Videosurg Miniinvasive Tech, 2016; 11:288–294.
13.
MartinDJ, LeeCMY, RigasG, et al.Predictors of weight loss 2 years after laparoscopic sleeve gastrectomy. Asian J Endosc Surg, 2015; 8:328–332.
14.
PekkarinenT, MustonenH, SaneT, et al.Long-term effect of gastric bypass and sleeve gastrectomy on severe obesity: Do preoperative weight loss and binge eating behavior predict the outcome of bariatric surgery?. Obes Surg, 2016; 26:2161–2167.
15.
CottamA, BillingJ, CottamD, et al.Long-term success and failure with SG is predictable by 3 months: A multivariate model using simple office markers. Surg Obes Relat Dis, 2017; 13:1266–1270.
16.
Cadena-ObandoD, Ramírez-RenteríaC, Ferreira-HermosilloA, et al.Are there really any predictive factors for a successful weight loss after bariatric surgery?. BMC Endocr Disord, 2020; 20:20.
17.
ChangS-H, StollCRT, SongJ, et al.The effectiveness and risks of bariatric surgery: An updated systematic review and meta-analysis, 2003–2012. JAMA Surg, 2014; 149:275–287.
18.
PerroneF, BianciardiE, BenavoliD, et al.Gender influence on long-term weight loss and comorbidities after laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass: A prospective study with a 5-year follow-up. Obes Surg, 2016; 26:276–281.
19.
Gras-MirallesB, HayaJR, MorosJMR, et al.Caloric intake capacity as measured by a standard nutrient drink test helps to predict weight loss after bariatric surgery. Obes Surg, 2014; 24:2138–2144.
20.
GarayM, Balagué C, Rodríguez-Otero C, et al. Influence of antrum size on gastric emptying and weight-loss outcomes after laparoscopic sleeve gastrectomy (preliminary analysis of a randomized trial). Surg Endosc, 2018; 32:2739–2745.
21.
SczepaniakJP, OwensML, GarnerW, et al.A simpler method for predicting weight loss in the first year after Roux-en-Y gastric bypass. J Obes, 2012; 2012:195251.
22.
GoulartA, LeãoP, CostaP, et al.Doctor, how much weight will i lose?—A new individualized predictive model for weight loss. Obes Surg, 2016; 26:1357–1359.
23.
DallalRM, QuebbemannBB, HuntLH, et al.Analysis of weight loss after bariatric surgery using mixed-effects linear modeling. Obes Surg, 2009; 19:732–737.
24.
LivingstonEH, SebastianJL, HuertaS, et al.Biexponential model for predicting weight loss after gastric surgery for obesity. J Surg Res, 2001; 101:216–224.
WoodGC, BenottiP, GerhardGS, et al.A patient-centered electronic tool for weight loss outcomes after Roux-en-Y gastric bypass. J Obes, 2014; 2014:364941.
27.
WiseES, HockingKM, KavicSM. Prediction of excess weight loss after laparoscopic Roux-en-Y gastric bypass: Data from an artificial neural network. Surg Endosc, 2016; 30:480–488.
28.
Velázquez-FernándezD, SánchezH, MonrazF, et al.Development of an Interactive Outcome Estimation Tool for laparoscopic Roux-en-Y gastric bypass in Mexico based on a cohort of 1002 patients. Obes Surg, 2019; 29:2878–2885.
29.
JanikMR, RogulaTG, MustafaRR, et al.Setting realistic expectations for weight loss after laparoscopic sleeve gastrectomy. Videosurg Miniinvasive Tech, 2019; 14:415–419.
30.
KarpińskaIA, KulawikJ, Pisarska-AdamczykM, et al.Is it possible to predict weight loss after bariatric surgery?—External validation of predictive models. Obes Surg, 2021; 31:2994–3004.
31.
SeysselK, SuterM, PattouF, et al.A predictive model of weight loss after Roux-en-Y gastric bypass up to 5 years after surgery: A useful tool to select and manage candidates to bariatric surgery. Obes Surg, 2018; 28:3393–3399.
32.
WelbournR, HollymanM, KinsmanR, et al.Bariatric surgery worldwide: Baseline demographic description and one-year outcomes from the Fourth IFSO Global Registry Report 2018. Obes Surg, 2019; 29:782–795.
33.
HayozC, HermannT, RaptisDA, et al.Comparison of metabolic outcomes in patients undergoing laparoscopic roux-en-Y gastric bypass versus sleeve gastrectomy—A systematic review and meta-analysis of randomised controlled trials. Swiss Med Wkly, 2018; 148:w14633.
34.
CarbonellAM, WolfeLG, MeadorJG, et al.Does diabetes affect weight loss after gastric bypass?. Surg Obes Relat Dis, 2008; 4:441–444.
35.
SchauerPR, BhattDL, KirwanJP, et al.Bariatric surgery versus intensive medical therapy for diabetes—5-Year outcomes. N Engl J Med, 2017; 376:641–651.
36.
BaltasarA, PerezN, SerraC, et al.Weight loss reporting: Predicted body mass index after bariatric surgery. Obes Surg, 2011; 21:367–372.
37.
CollinsGS, de GrootJA, DuttonS, et al.External validation of multivariable prediction models: A systematic review of methodological conduct and reporting. BMC Med Res Methodol, 2014; 14:40.
38.
AltmanDG, RoystonP. What do we mean by validating a prognostic model?. Stat Med, 2000; 19:453–473.
39.
MoonsKGM, KengneAP, GrobbeeDE, et al.Risk prediction models: II. External validation, model updating, and impact assessment. Heart Br Card Soc, 2012; 98:691–698.
40.
CollinsGS, MallettS, OmarO, et al.Developing risk prediction models for type 2 diabetes: A systematic review of methodology and reporting. BMC Med, 2011; 9:103.
41.
CoupayeM, Sabaté JM, Castel B, et al. Predictive factors of weight loss 1 year after laparoscopic gastric bypass in obese patients. Obes Surg, 2010; 20:1671–1677.
42.
StillCD, WoodGC, ChuX, et al.Clinical factors associated with weight loss outcomes after Roux-en-Y gastric bypass surgery. Obes Silver Spring Md, 2014; 22:888–894.
43.
AndersenJR, AadlandE, NilsenRM, et al.Predictors of weight loss are different in men and women after sleeve gastrectomy. Obes Surg, 2014; 24:594–598.
44.
CottamS, CottamD, CottamA. Sleeve gastrectomy weight loss and the preoperative and postoperative predictors: A systematic review. Obes Surg, 2019; 29:1388–1396.
45.
Is R-squared Useless? | University of Virginia Library Research Data Services + Sciences [Internet]. [cited November 28, 2020]. Accessed at https://data.library.virginia.edu/is-r-squared-useless/ on March 14, 2021.
46.
How to interpret R-squared in regression analysis—Statistics by Jim [Internet]. [cited November 28, 2020]. Accessed at https://statisticsbyjim.com/regression/interpret-r-squared-regression/ on March 14, 2021.
47.
El AnsariW, El-AnsariK. Missing something? Comparisons of effectiveness and outcomes of bariatric surgery procedures and their preferred reporting: Refining the evidence base. Obes Surg, 2020; 30:3167–3177.
48.
TestaG, GraneroR, SiragusaC, et al.Psychological predictors of poor weight loss following LSG: Relevance of general psychopathology and impulsivity. Eat Weight Disord EWD, 2020; 25:1621–1629.
49.
BrunaultP, FrammeryJ, CouetC, et al.Predictors of changes in physical, psychosocial, sexual quality of life, and comfort with food after obesity surgery: A 12-month follow-up study. Qual Life Res, 2015; 24:493–501.
50.
VergouweY, SteyerbergEW, EijkemansMJC, et al.Substantial effective sample sizes were required for external validation studies of predictive logistic regression models. J Clin Epidemiol, 2005; 58:475–483.
51.
CollinsGS, OgundimuEO, AltmanDG. Sample size considerations for the external validation of a multivariable prognostic model: A resampling study. Stat Med, 2016; 35:214–226.
52.
Van CalsterB, SteyerbergEW, CollinsGS, et al.Consequences of relying on statistical significance: Some illustrations. Eur J Clin Invest, 2018; 48:e12912.
