Parâmetros respiratórios e qualidade de vida de indivíduos obesos, antes e após gastroplastia redurora: um estudo longitudinal

Abstract

Obesity is responsible to a raise in population's morbidly and mortality, requiring effective treatment. Serious obese might suffer a large quantity health problem, some that threaten the life and/or limit the life diary activities, as laboral like familiar. The first aim of this study was to evaluate, in a longitudinal way, the breathing patterns, volume and time variables and thoracoabdominal motion of individuals obese, before and after gastroplasty surgery and to compare them to a control group of non obese pared by sex and age. The second aim was to evaluate the quality of life in obese individuals before and after gastroplasty surgery. In this study participated thirty obese class II and III (24 women and 6 men) submitted to gastroplasty surgery, with age of 32,37 8,54 years (mean standart deviation) and mean body mass index (BMI) of 42,72 4,10 Kg/m2 ; and one control group of thirty non obese with mean age of 30,607,76 and BMI of 21,992,22 Kg/m2. Calibrated respiratory inductive plethysmography was used to measure breathing pattern and thoracoabdominal motion on individuals obese, before and after one and six month of gastroplasty surgery and on participants of control group. The respiratory variables analysed in each respiratory cycle were: volume tidal (Vt), respiratory frequency (f), minute ventilation (VM), inspiratory time (Ti), expiratory time (Te), respiratory total time (Ttot), inspiratory duty cycle (Ti/Ttot), mean inspiratory flow (Vt/Ti), rib cage motion contribution to Vt (%RC/Vt), abdominal motion contribution to Vt (%AB/Vt=100 - %RC/Vt ), labor breathing index (LBI), phase angle-PhAng. To evaluate the obese's quality of life before and after one and six month of gastroplasty, the generic instrument Medical Outcomes Study short Form-36 (SF-36) and the specific instrument Impact of Weight on Quality of life-lite (IWQOL-Lite) were used. The SF-36 had its domains grouped into two components: physical (average between physical capacity, physical aspect, pain and vitality) and emotional (average between general health conditional, social aspect, social aspect and mental health). All domains of IWQOL-Lite were analysed: physical function (FF), self-steem (SE), sexual life (SL), public distress (PD), work (W), and total score. To compare the variables of the sample's caracterization between the control group and obese in pre-operative, statistical analysis was performed using Student t test to independent groups, when the distribution was considered normal and Mann-Whitney U when the distribution was different of normal. To compare BMI, breathing pattern and scores of life quality questionnaires between control group and obese before and after one and six month surgery, statistical analysis used were ANOVA for repeated measures followed by Tukey when the distribution was considered normal or test Friedman with post Wilcoxon test when the distribution was different of normal. It was calculated the power of the study on variables analysed by ANOVA. In domains of quality of life the confidence intervals and the size of a treatment's effects were calculated and 20 was considered the smallest clinically worthwhile effect, established accordant the clinical practice. Level of significance was set at 0.05. Obese presented progressive and significant reduction in BMI after surgery (p=0,000). The principals results observed on pos-operative period were: the obese presented significant decrease in Vt (p= 0,000 to all comparisons), with no change in f, producing significant decrease in VM on pos-operative period (p=0,01). It was observed significant reduction in Ti/Ttot on pos-operative period (p=0,01) and LBI after six month of surgery (p=0,01), as in PhAng after six month of surgery. In relation to control group, it was observed higher VM in before surgery period (p=0,004) that became similar on pos-operative period, as PhAng after six month of surgery. There were no significant differences in Vt/Ti, rib cage motion contribution to Vt and abdominal motion contribution to Vt (p>0,05). Considering results of quality of life, a progressive raise in the SF-36 emotional components (p=0,000) and in the IWQOL-Lite domains (FF, SE, PD and total score; p=0,000 to all comparison) was found, with statistic significant after one and six months of surgery (p=0,000). There was also a raise in the physical components of the SF-36 and the domains SL and work of the IWQOL-Lite, after six month of surgery (p=0,000 to all comparisons). Concluding, the results of this study suggest that obese presented progressive and significant reduction in BMI. The individuals obese presented significant changes in greater number the breathing pattern and thoracoabdominal motion, however, some variables presented similarity with results found in control group, suggesting the positive influence of weigh loss in respiratory variables. In relation to quality of life, this study suggest expressive change in life quality, because progressives improvements were found on pos-operative period in mayority of questionnaire scores after one and six month surgery.