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Featured researches published by Simon Biron.


World Journal of Surgery | 1998

Biliopancreatic Diversion with Duodenal Switch

Picard Marceau; Frédéric-Simon Hould; Serge Simard; Stéphane Lebel; Roch-André Bourque; Martin Potvin; Simon Biron

Abstract. In 1990 Scopinaro’s technique of biliopancreatic diversion with distal gastrectomy (DG) and gastroileostomy was modified. A sleeve gastrectomy with duodenal switch (DS) was used instead of the distal gastrectomy; and the length of the common channel was made 100 cm instead of 50 cm. A questionnaire and a prescription for blood work were sent to 252 patients who underwent DG a mean 8.3 years ago (range 6–13 years) and 465 patients who underwent DS 4.1 years ago (range 1.7–6.0 years). The questionnaire response rate was 93%, and laboratory work was completed for 65% of both groups. The mean weight loss after DG was 37 ± 21 kg and after DS 46 ± 20 kg. There were fewer side effects after DS: The number of daily stools was lower (p < 0.0002), as was the prevalence of diarrhea (p < 0.01), vomiting (p < 0.001), and bone pain (p < 0.001). Greater benefits related to several aspects of life were reported after DS than DG (p < 0.0001). The mean serum levels of ferritin, calcium, and vitamin A were higher (p < 0.001), and parathyroid hormone was lower. The yearly revision rate for excessive malabsorption was 1.7% per year after DG and 0.1% per year after DS. The two procedures were equally efficient for treating co-morbid conditions such as diabetes, hypertension, and hypercholesterolemia. Biliopancreatic diversion with sleeve gastrectomy/duodenal switch and a 100-cm common limb was shown to produce greater weight loss with fewer side effects.


Obesity Surgery | 1993

Biliopancreatic Diversion with a New Type of Gastrectomy

Picard Marceau; Simon Biron; Roch-André Bourque; Martin Potvin; Frédéric-Simon Hould; Serge Simard

In an attempt to improve the results of biliopancreatic diversion in the treatment of morbid obesity, two aspects of the procedure performed at Laval Hospital were modified to reduce adverse physiological consequences. The distal gastrectomy was replaced by a parietal gastrectomy which preserves vagal continuity along with the lesser curvature, and leaves intact the antro-pyloro-duodenal pump. The duodenum was stapled shut and nutrients were diverted through a duodeno-ileal anastomosis. The biliopancreatic diverting intestinal limb was anastomosed to the nutrient ileal limb 100 cm proximal to the ileocaecal valve instead of 50 cm proximal to it, thus doubling the length of the common ileal absorptive segment. Weight loss after either operation was greater than 70% of initial excess weight. Following the new operation, there was a lesser prevalence of side-effects, especially loose stools and malodorous gas, a lesser degree of hypocalcemia and no hypoalbuminemia. The duodenum recanalized at the staple line in 20% of the patients who had the new operation. When data from these patients were excluded, weight loss following the new operation was greater than that seen after the old one. The prevalence of side-effects and the degree of calcium and protein malabsorption remained significantly lower. Weight loss remained satisfactory with a common limb measuring 100 cm. The parietal gastrectomy was not restrictive as shown by the failure to lose further weight when the duodenal stapled diversion failed. Weight loss was thus mainly a function of biliopancreatic diversion, but increased weight loss in the new procedure despite a doubling of the common ileal limb suggests that parietal gastrectomy contributed to weight loss. Because duodenal recanalization can be corrected surgically and now prevented, the modified biliopancreatic bypass is preferred.


Pediatrics | 2006

Large maternal weight loss from obesity surgery prevents transmission of obesity to children who were followed for 2 to 18 years.

John G. Kral; Simon Biron; Serge Simard; Frédéric-Simon Hould; Stéfane Lebel; Simon Marceau; Picard Marceau

OBJECTIVE. Our aim was to compare the prevalence of obesity in 172 children who were aged 2 to 18 years and born to 113 obese mothers (BMI: 31 ± 9 kg/m2) with substantial weight loss after biliopancreatic bypass surgery with 45 same-age siblings who were born before maternal surgery (mothers’ BMI: 48 ± 8 kg/m2) and with current population standards. METHODS. In this case series, with >88% follow-up in a tertiary referral center, crosssectional office chart and telephone data on childhood and adolescent weights were transformed to z scores. RESULTS. After maternal surgery, the prevalence of obesity in the offspring decreased by 52% and severe obesity by 45.1%, with no increase in the prevalence of underweight. The z score reduction in obesity was gender specific, with boys reducing from 1.4 ± 1.3 before to 0.57 ± 1.7 after maternal surgery, corrected for birth order. The difference was not significant in girls (0.8 ± 1.3 vs 0.8 ± 1.2). Among children of both genders who were aged 6 to 18 years of age and born after maternal surgery, the prevalence of overweight was reduced to population levels. CONCLUSIONS. Contrary to outcomes after intrauterine under- and overnutrition, the prevalence of overweight and obesity in children of mothers with large voluntary postsurgical weight loss was similar to that in the general population, with no increase in underweight. The results demonstrate the importance of potentially modifiable epigenetic factors in the cause of obesity.


Surgical Clinics of North America | 2001

MALABSORPTIVE OBESITY SURGERY

Picard Marceau; Frédéric S. Hould; Stéfane Lebel; Simon Marceau; Simon Biron

Biliopancreatic diversion is the only valuable surgical approach for changing intestinal absorption. It is efficient in producing appropriate permanent weight loss and has a considerable psychological advantage because it does not impose abnormal food restriction. It not only decreases caloric absorption, but it also directly improves insulin and lipid metabolism. The ideal technique for the construction of BPD is not yet established, but our current preference is for the duodenal switch type. BPD must be seen as a means to change an intolerable and untreatable disease to a tolerable and treatable one, with substantial improvement in quality of life.


Obesity Surgery | 1995

Biliopancreatic Diversion with a New Type of Gastrectomy: Some Previous Conclusions Revisited.

Marc Lagacé; Picard Marceau; Simon Marceau; Frédéric-Simon Hould; Martin Potvin; Roch-André Bourque; Simon Biron

Background: In 1990, we modified Scopinaros biliopancreatic diversion (BPD); instead of a distal gastrectomy and gastroileal anastomosis, a parietal gastrectomy was performed with nutrients diverted through a duodenal switch. Also, the length of the common channel (50 cm) was doubled to 100 cm, while the nutrient limb remained 250 cm. In 1991, we reported initial results after 16 months: weight loss was as expected following BPD, but patients reported fewer side-effects and the prevalence of excessive malabsorption was less. This cohort of patients had their duodenum stapled shut to construct the duodenal switch. This staple-line failed insidiously in some patients, allowing the duodenum to recanalize partially or completely. This resulted in an incomplete BPD. Methods: Since 1992, the duodenal switch has been constructed with a complete transection of the duodenum to prevent recanalization. We report here on the first 61 patients who underwent this definitive procedure. Results: At 16 months, we observed a mean weight loss of 84% of initial excess weight, the number of daily stools at 2.9 ± 1.6 and the prevalence of diarrhea at 10%. Twenty per cent of patients experienced mild anaemia, hypocalcemia, or hypoalbuminemia, which required added supplements. Conclusions: BPD with parietal gastrectomy, duodenal switch and longer common channel improved weight loss and decreased gastrointestinal side-effects without an increased prevalence of excessive malabsorption. The parietal gastrectomy may contribute to weight loss by increasing satiety, and decreasing side-effects by regulating gastric emptying.


Journal of Gastrointestinal Surgery | 2002

Does bone change after biliopancreatic diversion

Picard Marceau; Simon Biron; Stéfane Lebel; Simon Marceau; Frédéric S. Hould; Serge Simard; Marcel Dumont; Lorraine A. Fitzpatrick

This prospective study evaluated bone changes after biliopancreatic diversion (BPD) consisting of a distal gastrectomy, a 250 cm alimentary channel, and a 50 cm common channel. Thirty-three consecutive patients had clinical, biochemical, and bone mineral density analysis before surgery and 4 and 10 years after surgery. Iliac crest bone biopsies and special tests including parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), 1,25-dihydroxyvitamin D (1,25-OH2-D), bone-specific alkaline phosphatase (BAP), and osteocalcin were obtained at surgery and 4 years postoperatively. Over the years, with close metabolic surveillance, additional calcium and vitamin D were given as indicated. After BPD, serum levels of calcium and vitamin D were decreased and serum levels of PTH, BAP, and osteocalcin were increased. Bone turnover and mineralization were both increased. Mean osteoid volume (P < 0.0007) and bone formation rate in relation to bone volume (P < 0.02) were increased. Static measures of bone were altered as follows: cortical thickness decreased (P < 0.01) and trabecular bone volume increased (P < 0.01). Ten years after surgery, overall bone mineral density was unchanged at the hip and was decreased by 4% at the lumbar spine. Overall fracture risk, based on the Z score, was unchanged. Preoperative factors predicting bone loss included menopause, smoking, and preexisting osteopenia. An elevated level of 1,25-OH2-D was also found to be a predictor of future bone loss (r = 0.40; P < 0.002). After surgery, a greater increase in bone markers and bone turnover was associated with an increased risk of bone loss. Although elevated osteocalcin levels were associated with overall bone loss (r = 0.52; P < 0.002), lower albumin levels were associated only with bone loss at hip level (r = 0.44; P < 0.02), whereas lower calcium levels were associated only with the loss at the lumbar spine (r = 0.39; P < 0.02). Ten years after surgery, bone loss at the hip continued to depend on albumin levels (r = 0.37; P < 0.03). We concluded that bone was relatively tolerant to the metabolic changes due to BPD. Provided that there is close surveillance for metabolic disturbances, the use of appropriate supplements, and the avoidance of malnutrition, the beneficial effects of surgery far outweigh the risk of postoperative bone disease.


Obesity Surgery | 2004

Asthma and sleep apnea in patients with morbid obesity: outcome after bariatric surgery.

Barbara Simard; Hélène Turcotte; Picard Marceau; Simon Biron; Frédéric S. Hould; Stéphane Lebel; Simon Marceau; Louis-Philippe Boulet

Background: Asthma and sleep apnea syndrome (SAS) are frequently reported in obese patients. The authors determined the prevalence of asthma and SAS in morbidly obese patients and the effect of biliopancreatic diversion with duodenal switch (BPD-DS) on these conditions. Methods: 398 patients were evaluated for bariatric surgery in a university-affiliated tertiary care center. All patients completed a written questionnaire on asthma and SAS before BPD-DS. In addition, 139 patients also completed a questionnaire on their general health status, including asthma and SAS, 2 years after the procedure. Results: For the cohort of 398 patients, the prevalence of self-reported asthma was 30.4% and that of SAS, 32.2%. No significant association was found between asthma and SAS diagnosis (P =0.10). Significant relationships were observed between the diagnosis of asthma and age, hip circumference, waist/hip ratio, weight and BMI of the patients as well as between a diagnosis of SAS and gender, waist circumference, hip circumference, waist/hip ratio, weight and BMI. 2 years after surgery (mean BMI was reduced from 51.4 to 30.5 kg/m2), asthma was reported improved in 79.3% of patients and SAS was improved in all but one with this condition; among 29 SAS patients using CPAP before surgery, only 4 were still using this treatment after 2 years. Conclusion: The prevalence of asthma and SAS is high in the morbidly obese population and is associated with markers of obesity. We found no association between the diagnosis of asthma and SAS diagnosis in this population. BPD-DS improved self-reported severity of asthma and SAS symptoms.


Obesity Surgery | 1995

Biliopancreatic Diversion, with Distal Gastrectomy, 250 cm and 50 cm Limbs: Long-term Results

Simon Marceau; Simon Biron; Marc Lagacé; Frédéric-Simon Hould; Martin Potvin; Roch-André Bourque; Picard Marceau

Background: Since 1984, biliopancreatic diversion (BPD) has been our procedure of choice in the treatment of morbid obesity. Better understanding of long-term outcome following BPD is needed. Methods: We report the results of our first consecutive 92 patients who underwent BPD more than 5 years ago. Of these 92, only 82 were available for a recent formal evaluation after a mean of 79 months. Results: Weight loss was maintained over the years at 62% of initial excess weight; the success rate for losing more than 50% of initial excess weight was 72%. The gastrointestinal side-effects decreased with time, but diarrhea was still present in 13%. The average number of daily stools was 3 ± 1.0. Of the patients, 76% were free from any gastrointestinal side-effects, taking normal diet and having normal stools. Malabsorption, however, was still present. A third of patients had laboratory values slightly below normal levels for haemoglobin, albumin and calcium. These values were mostly without clinical manifestation and were well tolerated by the patients. Regarding associated diseases, 75% were cured or improved following BPD. In 14 patients, reoperation was required to improve diarrhea or serum albumin. In these patients, the common channel was lengthened from 50 to 100 cm. The revision was successful in 11 and did not cause significant weight gain. Conclusion: BPD, as proposed by Scopinaro, was an efficient surgical treatment of morbid obesity that allowed normal eating habits and despite malabsorption was well tolerated by the great majority of patients.


Steroids | 2006

Omental and subcutaneous adipose tissue steroid levels in obese men.

Chantal Bélanger; Frédéric-Simon Hould; Stéfane Lebel; Simon Biron; Gaétan Brochu; André Tchernof

We examined plasma and fat tissue sex steroid levels in a sample of 28 men aged 24.8-62.2 years (average BMI value of 46.3 +/- 12.7 kg/m(2)). Abdominal adipose tissue biopsies were obtained during general or obesity surgery. Omental and subcutaneous adipose tissue steroid levels were measured by gas chromatography and chemical ionization mass spectrometry after appropriate extraction procedures. BMI and waist circumference were negatively correlated with plasma testosterone (r = -0.49 and -0.50, respectively, p < 0.01) and dihydrotestosterone (r = -0.58 and -0.56, respectively, p < 0.01), and positively associated with estrone levels (r = 0.64 and 0.62, respectively, p < 0.001). Regional differences in adipose tissue steroid levels were observed for dihydrotestosterone (p < 0.005), androstenedione (p < 0.0001) and dehydroepiandrosterone levels (p < 0.05), which were all significantly more concentrated in omental versus subcutaneous fat. Positive significant associations were found between circulating level of a steroid and its concentration in omental and subcutaneous adipose tissue, for estrone (r = 0.72 and 0.57, respectively, p < 0.01), testosterone (r = 0.66 and 0.58, respectively, p < 0.01) and dihydrotestosterone (r = 0.58 and 0.45, respectively, p < 0.05). Positive correlations were observed between plasma dehydroepiandrosterone-sulfate and omental (r = 0.56, p < 0.01) as well as subcutaneous adipose tissue dehydroepiandrosterone level (r = 0.38, p = 0.05). Positive significant associations were found between omental adipocyte responsiveness to positive lipolytic stimuli (isoproterenol, dibutyryl cyclic AMP and forskolin) and plasma or omental fat tissue androgen levels. In conclusion, although plasma androgen or estrogen levels are strong correlates of adipose tissue steroid content both in the omental and subcutaneous fat depots, regional differences may be observed. Androgen concentration differences in omental versus subcutaneous adipose tissue suggest a depot-specific impact of these hormones on adipocyte function and metabolism.


Surgery for Obesity and Related Diseases | 2009

Duodenal switch improved standard biliopancreatic diversion: a retrospective study.

Picard Marceau; Simon Biron; Frédéric-Simon Hould; Stéfane Lebel; Simon Marceau; Odette Lescelleur; Laurent Biertho; Serge Simard

BACKGROUND This was a retrospective study, performed 10 years after surgery, to compare the results between biliopancreatic diversion (BPD) with distal gastrectomy (DG) versus BPD with duodenal switch (DS). METHODS Complete follow-up data were available for 96% of patients, allowing a comparison of weight loss, revision, side effects, and complications at 10 years. RESULTS After BPD-DS, weight loss was 25% greater than after BPD-DG (46.8 +/- 21.7 kg versus 37.5 +/- 22 kg, respectively; P <.0001). The need for revision decreased from 18.5% to 2.7% (P <.0001), and the prevalence of vomiting during the previous month was 50% less (23.7-50.6%, P <.0001) after BPD-DS compared with after BPD-DG. Late complications were the same for both procedures. Blood analysis showed that, after BPD-DS, the levels of calcium, iron, and hemoglobin were significantly greater and the parathyroid hormone level was lower than after BPD-DG (71.3 +/- 44.2 versus 103.0 +/- 64.0 ng/L, respectively; P <.0001). CONCLUSION The DS greatly improved the BPD, as it was initially proposed. The use of the DS increased weight loss, decreased the need for revision, resulted in fewer side effects, and improved the absorption of nutrients.

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