Orlando Pereira Faria

University of Brasília, Brasília, Federal District, Brazil

Are you Orlando Pereira Faria?

Claim your profile

Publications (13)34.6 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Body mass index (BMI) is the most common parameter for classifying nutritional status. However, body composition (BC) may vary considerably among individuals with identical BMIs; consequently, we need to assess BC efficiently. Bariatric surgery is the most effective method for treating obesity. To improve quality assessment of postoperative weight loss, it is essential to assess BC. Multi-frequency bioelectrical impedance analysis (BIA) is a practical assessment instrument, though limited when applied among the obese population. Despite dual-energy X-ray absorptiometry (DXA) being the current reference standard, it has physical limitations which restrict its practical application. This study, therefore, sought to correlate the results of BC assessments of same patient population using BIA and DXA. This was a cross-sectional validation study with patients invited to undergo a multi-frequency BIA (Inbody 720®) and afterwards a DXA examination Statistical analyses were done using the intraclass correlation coefficient (ICC), paired t-test and the Bland-Altman plot analysis. A total of 108 patients were randomly selected, with 73 meeting the criteria for study inclusion. Most were female (89 %) and had an average BMI of 40.17 ± 4.08 kg/m(2). An almost perfect correlation of fat (kg) and fat-free mass (kg) was found in results from the BIA and DXA examination (ICC = 0.832 and ICC = 0.899, respectively). A substantial correlation was also found between the percentage of body fat (%BF) and the percentage of fat-free mass (%FFM). The comparison made between the BIA and DXA using the t-test showed significant differences between all parameters. The Bland-Altman plot showed that the BIA method tends to underestimate the FM and overestimate the LM measurements when compared with DXA. BIA proved to be a safe alternative for assessing BC in clinically severely obese patients and thus provides a more accessible evaluation tool for this population. But, consideration should be given to the formula added to the BIA measurement, adjusting the values to differences observed in order to reduce errors when compared with the DXA measurements.
    Obesity Surgery 01/2014; · 3.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background Preoperative bariatric patients can follow very low calorie diets (VLCD), reducing surgical risks. However, possible advantages of a liquid diet over one of normal consistency are controversial. Objectives This study investigated the effect of a liquid VLCD compared with one of normal consistency considering Visceral Fat (VF) loss and metabolic profile, in preoperative clinically severe obese patients. Setting Gastrocirurgia de Brasilia; Private Practice and University of Brasília, Brazil. Methodology This was a randomized, open-labeled, controlled clinical trial. Patients were divided into two groups: liquid diet and normal diet. Data were collected at baseline and 7 and 14 days after intervention. Information gathered was analyzed for loss of weight and VF, biochemical data, anthropometric data and energy intake. Results Fifty-seven patients consumed the liquid diet and 47 consumed the normal consistency diet. Liquid diet group lost significantly more weight (P<0.0290) and visceral fat (P<0.0410) than the normal diet group. An inverse correlation occurred between VF loss and surgical time among the liquid diet group (r2 = -0.1302, P= 0.001). Additionally, there was a positive correlation between the percentage of excess weight loss and ketonuria (P= 0.0070). No between-group difference occurred regarding calorie intake. Conclusion Patients that consumed a liquid diet presented a positive impact on reducing VF and greater weight loss than normal diet. Both VLCDs presented benefits offering a protective effect during the preoperative stage.
    Surgery for Obesity and Related Diseases 01/2014; · 4.12 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Computerized tomography is the gold-standard for measurement of abdominal visceral fat. However, it is costly and involves submitting patients to ionizing radiation. To validate the use of ultrasonography in assessing abdominal visceral fat among clinically serious obese patients of both genders. The sample included adult patients with clinically serious obesity with body mass index of 40kg/m2 or from 35kg/m2 to 40kg/m2 with co-morbidities. Abdominal visceral fat thickness was measured using ultrasound and tomography. Two ultrasonographic exams were conducted to assess the interobserver reproducibility among a patient subsample. Validation was done by comparing these results with the tomographic findings. The study included 13 patients (61.54% female) with an average BMI of 38.82 kg/m2. In terms of validation, the result obtained from applying the Pearson correlation coefficient was equal to 0.94 (p = 0.0005), showing a strong positive correlation between the two measurements. As for the results for reproducibility, the interobserver was equal to 0.822, with a confidence interval of 95% (-0.076 to 0.980), revealing good interobserver agreement. The average difference between the two ultrasound interobserver examination was equal to 0.10 ± 1.51 (p=0.8898) and so not significant. Interobserver bias was also not significant. The validation of ultrasonographic examination to replace tomographic method in assessing abdominal visceral fat among clinically serious obese patients was effective. The ultrasound measurement is independent of the examiner.
    Arquivos brasileiros de cirurgia digestiva : ABCD = Brazilian archives of digestive surgery. 01/2013; 26 Suppl 1:43-46.
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Roux-en-Y gastric bypass (RYGB) surgery is an effective tool for long-term weight loss. Mechanisms underlying the effectiveness of such surgery might result not only from the anatomic changes due to the procedure, but also from favorable changes in energy metabolism. Our objective was to evaluate the respiratory quotient (RQ), resting metabolic rate (RMR), and diet-induced thermogenesis (DIT) among clinically severe obese patients (control group) and patients who had undergone RYGB ≥1 year previously. The setting was Gastrocirurgia de Brasilia (Brasilia, Brazil). METHODS: The present study was cross-sectional and involved 35 clinically severe obese patients (body mass index ≥40 kg/m(2) or body mass index ≥35 kg/m(2) with co-morbidities) as the control group and 34 RYGB patients who had undergone the procedure ≥12 months previously (RYGB group). The anthropometric data (height and weight) were determined for both groups, and the RMR and RQ were measured using indirect calorimetry after a 12-hour fast. Patients then received a standard meal, and DIT was determined. The RMR and DIT were also adjusted per kilogram of body weight (BW), i.e BW-adjusted RMR and BW-adjusted DI. RESULTS: The BW-adjusted RMR and RQ did not differ between the 2 groups in the fasting period. However, the DIT of the RYGB group, whether absolute or BW-adjusted, was >200% that of the control group (P <.0001). The BW-adjusted DIT of the RYGB group correlated significantly with the percentage of excess weight loss (P = .0097). The postprandial RQ value among the RYGB group was also significantly (P <.0001) greater than that of the control group, suggesting an increased use of carbohydrates. CONCLUSION: Postprandial changes in energy expenditure and fuel use might contribute, in part, to the effectiveness of weight loss as a result of the RYGB procedure.
    Surgery for Obesity and Related Diseases 07/2012; · 4.12 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Weight loss may decrease the energy expenditure (EE) because of changes in body composition (BC). The reduction in EE may contribute, in part, to weight regain. Experimental studies in animals indicate that Roux-en-Y Gastric Bypass (RYGB) increases the resting metabolic rate (RMR) when adjusted for body weight (BW). Thus, the aim of this study was to assess the clinical effects of RYGB on EE in patients who have undergone RYGB. The study was prospective and included 46 RYGB patients whose RMR was assessed prior to and at least 6 months post-surgery by indirect calorimetry. BW and BC were measured at these same time points using bioelectric impedance. RMR was adjusted for changes in BW, i.e., kilocalories per kilogram. Statistical tests were used to analyze the results. The BW-adjusted RMR (kilocalories per kilogram) increased post-RYGB by 17.66 % (p < 0.0001). RMR adjusted for BW was negatively correlated to the total percentage of body fat preoperatively (r = -0.30729, p = 0.0378) and postoperatively (r = -0.46731, p = 0.0011) and was positively correlated to the fat-free mass percentage (%FFM) both preoperatively and postoperatively. Furthermore, BW-adjusted RMR and %FFM were positively correlated to percent excess weight loss (r = 0.55398, p < 0.0001 and r = 0.31677, p = 0.0283, respectively). Weight loss following RYGB is associated with an increase in BW-adjusted RMR and with %FFM. An increase in energy expenditure post-RYGB may be responsible, in part, for successful long-term weight loss of the RYGB procedure.
    Obesity Surgery 05/2012; 22(9):1450-5. · 3.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Since low basal metabolic rate (BMR) is a risk factor for weight regain, it is important to measure BMR before bariatric surgery. We aimed to evaluate the BMR among clinically severe obese patients preoperatively. We compared it with that of the control group, with predictive formulas and correlated it with body composition. We used indirect calorimetry (IC) to collect BMR data and multifrequency bioelectrical impedance to collect body composition data. Our sample population consisted of 193 patients of whom 130 were clinically severe obese and 63 were normal/overweight individuals. BMR results were compared with the following predictive formulas: Harris-Benedict (HBE), Bobbioni-Harsch (BH), Cunningham (CUN), Mifflin-St. Jeor (MSJE), and Horie-Waitzberg & Gonzalez (HW & G). This study was approved by the Ethics Committee for Research of the University of Brasilia. Statistical analysis was used to compare and correlate variables. Clinically severe obese patients had higher absolute BMR values and lower adjusted BMR values (p < 0.0001). A positive correlation between fat-free mass and a negative correlation between body fat percentage and BMR were found in both groups. Among the clinically severe obese patients, the formulas of HW & G and HBE overestimated BMR values (p = 0.0002 and p = 0.0193, respectively), while the BH and CUN underestimated this value; only the MSJE formulas showed similar results to those of IC. The clinically severe obese patients showed low BMR levels when adjusted per kilogram per body weight. Body composition may influence BMR. The use of the MSJE formula may be helpful in those cases where it is impossible to use IC.
    Obesity Surgery 04/2012; 22(8):1257-62. · 3.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Bariatric surgery, a highly successful treatment for obesity, requires adherence to special dietary recommendations to insure the achievement of weight loss goals and weight maintenance. Postoperative consumption of protein is linked to satiety induction, nutritional status, and weight loss. Hence, we conducted an extensive literature review to identify studies focused on the following: protein and nutritional status; recommendations for dietary protein intake; the effects of protein-rich diets; and associations between dietary protein intake and satiety, weight loss, and body composition. We found that there have been few studies on protein intake recommendations for bariatric patients. Dietary protein ingestion among this population tends to be inadequate, potentially leading to a loss of lean body mass, reduced metabolic rates, and physiological damage. Conversely, a protein-rich diet can lead to increased satiety, enhanced weight loss, and improved body composition. The quality and composition of protein sources are also very important, particularly with respect to the quantity of leucine, which helps to maintain muscle mass, and thus is particularly important for this patient group. Randomized studies among bariatric surgery patient populations are necessary to establish the exact quantity of protein that should be prescribed to maintain their nutritional status.
    Obesity Surgery 05/2011; 21(11):1798-805. · 3.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: OBJETIVO: Correlacionar dados antropométricos e de FMR de mulheres eutróficas e obesas. MÉTODOS: A amostra foi formada por 103 mulheres sedentárias, dividas em dois grupos: 57 obesas e 46 eutróficas. Foram realizadas medidas da circunferência da cintura (CC) e do quadril (CQ) para cálculo da relação cintura/quadril (RC/Q) e coletados as Pressões Respiratórias Máximas (PRM) pela manovacuometria com aparelho analógico de ± 300cmH2O. Para a mensuração da composição corporal, utilizou-se a Bioimpedância Tetrapolar, análise descritiva com o teste T de Student para amostras independentes, correlação de Pearson e regressão linear múltipla com método stepwise. O nível de significância adotado foi p < 0,05. RESULTADOS: A análise demonstrou diferença significativa nas PRM de eutróficas (Pimáx = -73,04±16,55 cm H2O e Pemáx = 79,67±18,89 cm H2O) e de obesas (Pimáx = -85,00±21,69 cm H2O e Pemáx=103,86±20,35 cm H2O). As variáveis da antropometria e da manovacuometria não apresentaram correlação significante nos grupos. Ao analisar a influência da bioimpedância sobre a FMR, observou-se uma correlação positiva da quantidade de massa magra com a Pimáx. CONCLUSÃO: As variavéis da bioimpedância e a obesidade apresentaram uma relação direta com a FMR. As variáveis CC e RC/Q não influenciaram na FMR nas obesas, porém há uma relevância com os fatores de risco para doenças associadas. Acreditamos que esses resultados se devam a uma adaptação ao excesso de peso ao longo dos anos.
    Revista da Associação Médica Brasileira 12/2009; 56(4):403-408. · 0.77 Impact Factor
  • Silvia Leite Faria, Emily Kelly, Orlando P Faria
    [Show abstract] [Hide abstract]
    ABSTRACT: Although Roux-en-Y gastric bypass (RYGBP) is a highly effective treatment for clinically severe obesity, not all patients achieve desirable weight loss and maintenance. There is some evidence that weight loss can induce a disproportionate reduction in resting metabolic rate (RMR). This reduction in RMR can be related to fat-free mass (FFM) loss, as FFM is the greatest responsible for variations in energy expenditure at rest. Abnormally low basal metabolic rate may predispose surgical patients to weight regain. Thirty-six individuals were divided into two groups: patients who have kept a healthy weight 2 years after surgery and patients who showed weight regain of at least 2 kg 2 years after the surgery. Selected patients have signed a consent form. Body mass index and excess weight loss were evaluated. RMR and body fat percentage were measured. FFM is a heterogeneous component that can be partitioned into muscle mass and no-muscle mass. The FFM was calculated as the result of subtracting total fat weight from total body weight in kilogram. We also wanted to know if the predictive formulas to assess RMR overestimate energy expenditure in these patients. Statistical tests were used to analyze the two groups. We found out that the RMR of the weight regain group was statistically inferior to the mean of the healthy weight group-the difference between the two groups was about 260 kcal/day. We also found out that the predictive formulas overestimate the RMR in the weight regain group. This study suggests that a lower RMR may contribute to weight regain in patients who undergo RYGBP. It is important to ensure ways to elevate energy expenditure in the patient, such as increasing the percentage of fat-free mass in the body and the practice of physical activities.
    Obesity Surgery 05/2009; 19(7):856-9. · 3.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In bariatric surgery patients, weight loss and long-term weight maintenance are related to food intake and eating patterns. To improve the diet orientation in the bariatric surgery postoperative period, we assessed the postoperative eating patterns and related them to weight loss. This was a transversal, analytical, and descriptive study that assessed body mass index (BMI) values and percentage of excess weight loss (%EWL) in patients who had undergone Roux-en-Y gastric bypass (RYGBP) surgery. The eating pattern and energy intake were investigated based on data collected through a 4-day food intake record. From these records, we assessed the number of daily meals, the quantity of food per meal, and calorie value of snacks between main meals. Based on these records, patients were classified under sweet-eating, snack-eating, or normal-eating patterns. Seventy-five patients met our inclusion criteria. The normal-eating pattern group was the one with the greatest weight loss with an average %EWL of 71.4 +/- 21%, followed by the sweet-eating pattern with 69.9 +/- 16.8%, and the snack-eating pattern with 56.4 +/- 16.7%. This difference was significant only between the first and the third group (p = 0.04). The snack-eating patients had the highest caloric intake and highest number of daily meals (p < 0.01). Postoperative eating pattern influenced postbariatric surgery weight loss. In the present study, the snack-eating pattern was associated with the worst weight loss outcome, followed by the sweet-eating and normal-eating patterns. A screening and a differential approach to patients according to their eating patterns may lead to better results of weight loss.
    Obesity Surgery 10/2008; 19(9):1293-6. · 3.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Weight loss and long-term weight maintenance in bariatric surgery patients are related to maintaining satiety. It can be related to glycemic load (GL) and carbohydrate (g CHO) intake. The aim of this study was to investigate the effect of g CHO and GL and in weight loss on patients who had undergone bariatric surgery. The following measurements/calculations were conducted as follows: current body weight (kg), current BMI, percentage of excess weight loss (PEWL), average monthly weight loss (AMWL), energy intake (kcal per day), and GL calculation. Correlations were found among the studied variables. A multiple linear regression analysis of diet variables executed with GL and weight loss. The population presented 66% of EWL. The average of total energy intake (TEI) was 1220+/-480, and the calculated GL resulted in an average of 73.2. Negative correlations were found between AMWL and TEI (p=0.04), and between AMWL and GL (p=0.009); furthermore, a negative correlation was found between carbohydrate intake in grams and AMWL (p=0.003). A positive correlation (p=0.017) was found between GL and TEI. Weight loss and GL were also correlated. Among the intake variables, GL and g CHO consumed are held accountable for 62 percent of AMWL. The multiple linear regression analysis showed that GL and carbohydrate grams (g CHO) account for 62% of AMWL. The glycemic load and grams of carbohydrate are intake factors that can be useful tools in weight loss and long-term weight maintenance on patients who have undergone Roux-en-Y Gastric Bypass (RYGB).
    Obesity Surgery 08/2008; 19(6):708-16. · 3.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to propose dietetic guidelines for the nutritional management of weight regain in Roux-en-Y gastric bypass (RYGB) patients. Thirty patients more than 2 years after RYGB surgery were followed up once every 15 days for at least 3 months. We collected from the medical records weight before surgery, excess weight, minimum weight reached 2 years after surgery, and percent of body fat before the operation. Current weight and bioelectrical impedance analysis were assessed at every appointment. The prescribed diet had a low glycemic load with 45% of carbohydrates, 35% of protein (80 g for women and 100 g for men) and 20% of fat, three servings of dairy products, and a supplement of soluble fibers (15 g/day). The patients had a previous average weight regain of 8 kg (+/-19). Forty percent of the sample had an excess weight loss (EWL) of less than 50%. After the intervention, 86% of the patients lost weight. The mean weight lost was 1.8 kg in the first month, 1.2 kg in the second month, and 1.3 kg in the third. Half of the sample with unsuccessful weight loss achieved an EWL of at least 50%. The failure rate of the group dropped from 40% to 20%. The percentage of body fat declined from 36.2% to 34% (p < 0.001). Despite the short period of time, we observed that the nutritional counseling reduced the weight of patients with previous weight regain. There was also a reduction in body fat, which improves the perspective of weight maintenance in the future.
    Obesity Surgery 07/2008; 20(2):135-9. · 3.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To correlate anthropometric data and respiratory muscle strength (RMS) of normal-weight and obese women. The sample consisted of 103 sedentary women, divided into two groups: 57 obese and 46 normal-weight women. Waist circumference (WC) and hip circumference (HC) were measured to calculate the waist-to-hip ratio (WHR), and maximal respiratory pressures (Pmax) were determined using an analog vacuum manometer to ± 300 cm H2O. Body composition was measured using tetrapolar bioelectrical impedance analysis. Descriptive statistics was used for data analysis, in addition to the Student t test for independent samples, Pearson correlation, and stepwise multiple linear regression analysis. Significance level was set at p ≤ 0.05. The analysis showed significant differences in Pmax of normal-weight women (PImax = -73.04±16.55 cm H2O and PEmax = 79.67±18.89 cm H2O) and obese women (PImax = -85.00±21.69 cm H2O and PEmax = 103.86±20.35 cm H2O). Anthropometric and manometric variables showed no significant correlation in both groups. When analyzing the influence of bioelectrical impedance on RMS, a positive correlation was observed between lean body mass and PImax. Bioelectrical impedance and obesity showed a direct correlation with RMS. WC and WHR had no influence on RMS of obese women; however, a relevance to risk factors for associated diseases was observed. We believe that these results are due to an adjustment to excess body weight over the years.
    Revista da Associação Médica Brasileira 56(4):403-8. · 0.77 Impact Factor