Data mining e modelos de regressão na determinação dos preditores de perda de peso com um e cinco anos de Bypass gástrico em Y de Roux

Orientador: Prof. Dr. Antônio Carlos Ligocki CamposCoorientador: Prof. Dr. José Simão de Paula PintoTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Clínica Cirúrgica. Defesa : Curitiba, 09/03/2018Inclui referênciasResumo: Introdução: A cirurgia bariátrica é considerada a forma de tratamento mais eficaz para a obesidade mórbida. A perda ponderal, controle ou remissão das comorbidades e melhora na qualidade de vida são resultados esperados no pós-operatório. A utilização de data mining é indicada na definição de variáveis preditivas e os modelos de regressão permitem a correlação das variáveis definindo o quanto uma influencia na outra. Objetivo: identificar os preditores para a baixa perda de peso no primeiro ano de pósoperatório de cirurgia bariátrica e de risco de reganho ponderal, com 5 anos de cirurgia. Objetiva-se também verificar a correlação destes fatores com a presença de comorbidades e satisfação do paciente com os resultados da cirurgia e estabelecer uma equação para estimativa do IMC médio com 5 anos de pós-operatório. Metodologia: Trata-se de um estudo longitudinal e retrospectivo, realizado com dados de prontuários de 388 pacientes submetidos ao Bypass Gástrico em Y de Roux, por videolaparoscopia. Foram coletados dados do pré-operatório (n=388), com 1 ano de pós-operatório (n= 388) e com 5 anos de pós-operatório (n=204). A aplicação de data mining foi realizada através da técnica de elaboração de árvores de classificação e regressão para a definição dos preditores do percentual de perda de excesso de peso (%PEP) com um ano de cirurgia, de IMC com um ano e 5 anos de cirurgia e de reganho de peso (RP) com 5 anos de cirurgia. O modelo ajustado para verificar as variáveis associadas ao %PEP e IMC com um ano de cirurgia e o RP com 5 anos, foi o de regressão linear múltipla. Para a elaboração da equação para estimativa do IMC médio com 5 anos de cirurgia bariátrica, foi utilizado um modelo linear generalizado com distribuição tweedie. Para finalizar, o teste de Mann Whitney (p39,84 kg/m²) e idade superior a 32 anos no pré-operatório. A baixa PEP, IMC no pré-operatório e IMC com um ano de cirurgia foram preditores para IMC mais alto com 5 anos de cirurgia. Fatores dietéticos do préoperatório não influenciaram na perda de peso no pós-operatório. Os modelos de regressão possibilitaram identificar a correlação entre as variáveis preditoras de perda de peso e a elaboração da equação para estimativa do IMC médio com 5 anos de cirurgia. A partir da interpretação dos modelos de regressão, observou-se que pacientes com baixos níveis sanguíneos de ácido fólico e de HDL, maior IMC e diagnóstico médico de ansiedade e/ou depressão no pré-operatório tinham maior IMC com 5 anos de cirurgia bariátrica. Observouse também que o maior IMC aos 5 anos de cirurgia esteve associado à maior prevalência de comorbidades, reganho de peso e insatisfação com os resultados da cirurgia. Conclusões: Os preditores identificados para PEP com um ano de cirurgia foram: idade, maior IMC e presença de hipertensão arterial. A PEP e IMC com um ano de cirurgia foram preditores do IMC com 5 anos de cirurgia. Níveis sanguíneos de ácido fólico e HDL, IMC e quadro de depressão e/ou ansiedade no pré-operatório foram fatores de risco para falha nos resultados do pós-operatório tardio e devem ser monitorados durante a avaliação clínica desde o préoperatório. Palavras-chave: Data mining. Cirurgia bariátrica. IMC. Perda de excesso de peso. Reganho de peso. Comorbidades.Abstract: Introduction: Bariatric surgery is considered the most effective form of treatment for morbid obesity. Weight loss, control or remission of comorbidities and the improvement in life quality are the expected postoperative results. The use of data mining is indicated in defining predictive variables and regression models enable the correlation of such variables, defining how much of an influence they have on each other. Objective: to identify the predictors for low weight loss in the first year of postoperative bariatric surgery and the risk of weight-increase, at 5 years following surgery. It is also aimed at checking the correlation of these factors with the presence of comorbidities and the patient's satisfaction with the results of the surgery, in addition to establishing an equation for estimating the average BMI following 5 years postoperative. Methodology: This is a longitudinal and retrospective study, carried out using data taken from the medical records of 388 patients that underwent Roux-en- Y Gastric Bypass, through video laparoscopy. Preoperative data were gathered (n=388), at 1 year postoperative (n=388) and at 5 years postoperative (n=204). The application of data mining was carried out through the elaboration of classification and regression trees for defining the predictors of the excess weight loss percentile (%EWL) at one year of surgery, of the BMI at one and 5 years following surgery and weight regain (WR) following 5 years of surgery. The adjusted model for checking which variables are linked to %EWL and BMI at one year following surgery and the WR following 5 years, was that of multiple linear regression. For elaborating the equation for estimating the average BMI at 5 years of bariatric surgery, a generalized linear model with Tweedie distribution, was used. Finally, the Mann Whitney test (p 39.84 kg / m²), and age above 32 in the preoperative period. Low EWL, preoperative BMI and BMI following one year of surgery were identified as predictors for a higher BMI at 5 years following surgery. Dietary factors of the preoperative period did not influence weight loss in the postoperative. The regression models enable the identification of a correlation between the predicting weight loss variables and the elaboration of the equation for estimating the average BMI at 5 years post-surgery. From the interpretation of the regression models, it was possible to observe that patients with blood results showing low levels of folic acid and higher levels high HDL cholesterol, a higher BMI and having been diagnosed with preoperative anxiety and/or depression, had a higher BMI at 5 years following bariatric surgery. It was also observed that the highest BMI at 5 years following surgery was linked to a higher prevalence of comorbidities, weight regain and patient dissatisfaction with the results of the surgery. Conclusions: The predictors identified for EWL at one year following surgery were: age, higher BMI and presence of arterial hypertension. The EWL and BMI at one year of surgery were predictors for BMI at 5 years following surgery. Folic acid and HDL cholesterol blood levels, BMI, and a preoperative depression and/or anxiety may be considered risk factors for late postoperative outcomes and should be monitored during the pre-operative clinical evaluation and at one year of surgery. Keywords: Data mining. Bariatric surgery. BMI. Excess weight loss. Weight regain. Comorbiditie

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants.

BACKGROUND: Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. METHODS: We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. FINDINGS: The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. INTERPRETATION: Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings. FUNDING: WHO

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings. Copyright (C) 2021 World Health Organization; licensee Elsevier

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

Data mining e modelos de regressão na determinação dos preditores de perda de peso com um e cinco anos de Bypass gástrico em Y de Roux

Orientador: Prof. Dr. Antônio Carlos Ligocki CamposCoorientador: Prof. Dr. José Simão de Paula PintoTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Clínica Cirúrgica. Defesa : Curitiba, 09/03/2018Inclui referênciasResumo: Introdução: A cirurgia bariátrica é considerada a forma de tratamento mais eficaz para a obesidade mórbida. A perda ponderal, controle ou remissão das comorbidades e melhora na qualidade de vida são resultados esperados no pós-operatório. A utilização de data mining é indicada na definição de variáveis preditivas e os modelos de regressão permitem a correlação das variáveis definindo o quanto uma influencia na outra. Objetivo: identificar os preditores para a baixa perda de peso no primeiro ano de pósoperatório de cirurgia bariátrica e de risco de reganho ponderal, com 5 anos de cirurgia. Objetiva-se também verificar a correlação destes fatores com a presença de comorbidades e satisfação do paciente com os resultados da cirurgia e estabelecer uma equação para estimativa do IMC médio com 5 anos de pós-operatório. Metodologia: Trata-se de um estudo longitudinal e retrospectivo, realizado com dados de prontuários de 388 pacientes submetidos ao Bypass Gástrico em Y de Roux, por videolaparoscopia. Foram coletados dados do pré-operatório (n=388), com 1 ano de pós-operatório (n= 388) e com 5 anos de pós-operatório (n=204). A aplicação de data mining foi realizada através da técnica de elaboração de árvores de classificação e regressão para a definição dos preditores do percentual de perda de excesso de peso (%PEP) com um ano de cirurgia, de IMC com um ano e 5 anos de cirurgia e de reganho de peso (RP) com 5 anos de cirurgia. O modelo ajustado para verificar as variáveis associadas ao %PEP e IMC com um ano de cirurgia e o RP com 5 anos, foi o de regressão linear múltipla. Para a elaboração da equação para estimativa do IMC médio com 5 anos de cirurgia bariátrica, foi utilizado um modelo linear generalizado com distribuição tweedie. Para finalizar, o teste de Mann Whitney (p39,84 kg/m²) e idade superior a 32 anos no pré-operatório. A baixa PEP, IMC no pré-operatório e IMC com um ano de cirurgia foram preditores para IMC mais alto com 5 anos de cirurgia. Fatores dietéticos do préoperatório não influenciaram na perda de peso no pós-operatório. Os modelos de regressão possibilitaram identificar a correlação entre as variáveis preditoras de perda de peso e a elaboração da equação para estimativa do IMC médio com 5 anos de cirurgia. A partir da interpretação dos modelos de regressão, observou-se que pacientes com baixos níveis sanguíneos de ácido fólico e de HDL, maior IMC e diagnóstico médico de ansiedade e/ou depressão no pré-operatório tinham maior IMC com 5 anos de cirurgia bariátrica. Observouse também que o maior IMC aos 5 anos de cirurgia esteve associado à maior prevalência de comorbidades, reganho de peso e insatisfação com os resultados da cirurgia. Conclusões: Os preditores identificados para PEP com um ano de cirurgia foram: idade, maior IMC e presença de hipertensão arterial. A PEP e IMC com um ano de cirurgia foram preditores do IMC com 5 anos de cirurgia. Níveis sanguíneos de ácido fólico e HDL, IMC e quadro de depressão e/ou ansiedade no pré-operatório foram fatores de risco para falha nos resultados do pós-operatório tardio e devem ser monitorados durante a avaliação clínica desde o préoperatório. Palavras-chave: Data mining. Cirurgia bariátrica. IMC. Perda de excesso de peso. Reganho de peso. Comorbidades.Abstract: Introduction: Bariatric surgery is considered the most effective form of treatment for morbid obesity. Weight loss, control or remission of comorbidities and the improvement in life quality are the expected postoperative results. The use of data mining is indicated in defining predictive variables and regression models enable the correlation of such variables, defining how much of an influence they have on each other. Objective: to identify the predictors for low weight loss in the first year of postoperative bariatric surgery and the risk of weight-increase, at 5 years following surgery. It is also aimed at checking the correlation of these factors with the presence of comorbidities and the patient's satisfaction with the results of the surgery, in addition to establishing an equation for estimating the average BMI following 5 years postoperative. Methodology: This is a longitudinal and retrospective study, carried out using data taken from the medical records of 388 patients that underwent Roux-en- Y Gastric Bypass, through video laparoscopy. Preoperative data were gathered (n=388), at 1 year postoperative (n=388) and at 5 years postoperative (n=204). The application of data mining was carried out through the elaboration of classification and regression trees for defining the predictors of the excess weight loss percentile (%EWL) at one year of surgery, of the BMI at one and 5 years following surgery and weight regain (WR) following 5 years of surgery. The adjusted model for checking which variables are linked to %EWL and BMI at one year following surgery and the WR following 5 years, was that of multiple linear regression. For elaborating the equation for estimating the average BMI at 5 years of bariatric surgery, a generalized linear model with Tweedie distribution, was used. Finally, the Mann Whitney test (p 39.84 kg / m²), and age above 32 in the preoperative period. Low EWL, preoperative BMI and BMI following one year of surgery were identified as predictors for a higher BMI at 5 years following surgery. Dietary factors of the preoperative period did not influence weight loss in the postoperative. The regression models enable the identification of a correlation between the predicting weight loss variables and the elaboration of the equation for estimating the average BMI at 5 years post-surgery. From the interpretation of the regression models, it was possible to observe that patients with blood results showing low levels of folic acid and higher levels high HDL cholesterol, a higher BMI and having been diagnosed with preoperative anxiety and/or depression, had a higher BMI at 5 years following bariatric surgery. It was also observed that the highest BMI at 5 years following surgery was linked to a higher prevalence of comorbidities, weight regain and patient dissatisfaction with the results of the surgery. Conclusions: The predictors identified for EWL at one year following surgery were: age, higher BMI and presence of arterial hypertension. The EWL and BMI at one year of surgery were predictors for BMI at 5 years following surgery. Folic acid and HDL cholesterol blood levels, BMI, and a preoperative depression and/or anxiety may be considered risk factors for late postoperative outcomes and should be monitored during the pre-operative clinical evaluation and at one year of surgery. Keywords: Data mining. Bariatric surgery. BMI. Excess weight loss. Weight regain. Comorbiditie