Optimization of Epicardial Fat Thickness Change in Obese Patients with Weight Loss by Bariatric 1 Surgery Using Central Composite and Box-Behnken Design

13 Background: The aim of our study was to determine the optimization of the change in epicardial fat 14 thickness in obese patients who underwent bariatric surgery with Central Composite (CCD) and Box- 15 Behnken Experimental design (BBD). 16 Methods: Response Surface Methods are used to see the sensitivity of the assessment criterion to changes 17 in design variables, and even to obtain the necessary correlations experimentally. Response surface 18 methods are evaluated in two different ways as CCD and BBD design. In this study, 3 3 experimental 19 designs were designed. The study data consisted of 40 obese patients who lost weight by bariatric surgery 20 between February 2015 and December 2016. Body Mass Index (BMI), Age and HOMA values were 21 evaluated in 3 categories and 3 levels, and response variable was the change in Epicardial Fat Thickness 22 (ΔEFT). 23 Results: As a result of CCD analysis, Age = 30.52, BMI = 45.30, HOMA = 34.62, the optimum ΔEFT = 24 2.571. As a result of BBD analysis, Age = 38.36, BMI = 63.18, HOMA = 14.95, the optimum ΔEFT = 3.756. Optimum ΔEFT is modeled with Contour and Response surface graphics. Conclusion: According to the results of the analysis, it was found that BBD analysis for optimum ΔEFT was more positive than CCD and optimum age, BMI and HOMA combinations were determined to reach 28 maximum ΔEFT.


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It is well known that obesity is one of the greatest public health challenges and individuals with obesity have

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It was previously showed that increased EFT which is an predictor of visceral adiposity and early atherosclerotic 76 structural changes may be reversed by sustained weight loss following bariatric surgery in asymptomatic obese 77 patients in a prospective study design [5].

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The aim of our study was to determine the optimization of the change in EFT in obese patients who underwent 79 bariatric surgery with Central Composite (CCD) and Box-Behnken Trials (BBD).   ii) The model shall have at least 1 + 2k + k (k-1) 2 different parameters. As a result, the trial order 1 + 2k + k (k-94 1) should contain data from 2 different points.

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In these experiments, the point where the dependent variable takes its maximum or minimum value is called 96 stationary point [9]. This point is located at the center of the system shown as ellipses. In some cases, the central 97 point in the center indicates neither the maximum nor the minimum value. In this case, the static point is called 98 the saddle point, and the system is called saddle system. One of the most important points in the method of 99 second order response surfaces are stationary points. 3D graphics (response surface and contour graph) helps to 100 determine these points.   ii) For each of the factors included in a model, partial derivatives are taken and equalized to zero.
iii) Equivalent which obtained in step ii. (2.2) solves the equation system. A value will be obtained for each 108 factor. These values are substituted in the model and the predicted variable value is obtained for the stationary 109 points.

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It is also possible to obtain constant points with matrices. If the given model is expressed in matrices;

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BBD design is planned as 3 factors and 3 central points.

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Body mass index and waist circumference are the widely accepted measurements of generalized adiposity; 223 however they are poor indicators for visceral obesity. It is well known that visceral adipose tissue accumulation 224 is associated with subclinical atherosclerosis and increased cardiovascular risk more strongly than generalized adiposity [19]. Emerging data have suggested that EFT is a reliable method to assess visceral adiposity and 226 strongly correlates with cardio-metabolic risk factors independent of overall adiposity [20,21]. EFT ≥5 mm was 227 found to be associated with higher incidence of detectable carotid atherosclerosis [21]. In addition EFT may be a 228 modifiable factor for CVD or a target to modify cardiovascular risk [22]. Early atherosclerotic structural changes 229 including EFT and carotid intima media thickness may be reversed or improved by sustained weight loss 230 following LSG in asymptomatic obese patients (5).

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Patient are generally operated according to standard bariatric surgical indications in guidelines [23,24]. However

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• We referred to all of the articles I used in this study with appropriate references,

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• We have not made any changes to the data used and the results,

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• The information and findings specified in this study are original.

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We declare above mentioned issues and accept all rights losses that may arise against me.