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Picard Marceau

Publications and source records attributed to Picard Marceau.

At least 19 recordsLinked to original sources

Plasma concentration of organochlorine compounds is associated with age and not obesity.

It has been suggested that obese individuals, because of an increased dilution space (body fat) for lipophilic organochlorines compounds, may have greater levels of toxic pollutants than lean sedentary individuals. It is important to further examine this possibility because of the potential contribution of organochlorine pesticides in the development of Parkinson's disease and other neurological diseases. The aim of this study was to further investigate the relationship between the magnitude of obesity and the plasma concentration of organochlorines for a wide range of BMI (with participants at steady state body weight). Fifty-three individuals were selected on the basis of their body mass index (BMI): lean controls (n=16; mean BMI 22.8+/-2.2 kg/m(2); mean age 38.8+/-9.4 years), obese individuals (n=19; mean BMI 33.4+/-3.0 kg/m(2); mean age 38.6+/-7.6 years) and morbidly obese individuals (n=18; mean BMI 49.3+/-6.5 kg/m(2); mean age 44.3+/-9.2 years). Blood samples were analyzed for organochlorine compounds. The relationship between the total plasma organochlorine concentration and BMI was tested using a multiple regression analysis. Age was included in the model. There was no relationship between the total plasma organochlorine concentration and BMI. Organochlorine concentrations, however, were correlated with age (BMI-adjusted R(2)=0.46; p<0.001). At steady state body weight, toxic pollutant concentrations are not associated to obesity but strongly correlate with age.

Adult↗

Body weight is a strong predictor of postural stability.

Proper balance control is a key aspect of acitivities of daily living. The aim of this study was to determine the contribution of body weight to predict balance stability. The balance stability of 59 male subjects with BMI ranging from 17.4 to 63.8kg/m(2) was assessed using a force platform. The subjects were tested with and without vision. A stepwise multiple regression analysis was used to determine the independent effect of body weight, age, body height and foot length on balance stability (i.e., mean speed of the center of foot pressure). With vision, the stepwise multiple regression revealed that body weight accounted for 52% of the variance of balance stability. The addition of age contributed a further 3% to explain balance control. Without vision, body weight accounted for 54% of the variance and the addition of age and body height added a further 8% and 1% to explain the total variance, respectively. The final model explained 63% of the variance. A decrease in balance stability is strongly correlated to an increase in body weight. This suggests that body weight may be an important risk factor for falling. Future studies should examine more closely the combined effect of aging and obesity on falling and injuries and the impact of obesity on the diverse range of activities of daily living.

Adult↗

Metabolic profile in severely obese women is less deteriorated than expected when compared to moderately obese women.

BACKGROUND: Obesity is well known to be associated with an increased prevalence of metabolic complications. Severe obesity is thus expected to have more important alterations of the metabolic profile than moderate obesity. This study aimed to compare the metabolic profile of pre- and postmenopausal severely obese women with moderately obese women. METHODS: First, the metabolic profile of pre- (n=165) and postmenopausal (n=43) severely obese women (body mass index (BMI) > or =40 kg/m(2)) was compared to that of pre- (n=52) and postmenopausal (n=35) moderately obese women (BMI of 30-40 kg/m(2)). Thereafter, pre- and postmenopausal severely obese women were divided into two subgroups according to the presence/absence of a dysmetabolic profile. We used for comparison, a group of pre- and postmenopausal moderately obese women without a dysmetabolic profile. RESULTS: The metabolic profile of pre- and postmenopausal severely obese women was less deteriorated than expected when compared to moderately obese women. Moreover, severely obese women with or without a dysmetabolic profile displayed comparable or even lower plasma levels of cholesterol, HDL and LDL-cholesterol, and a lower cholesterol/HDL-cholesterol ratio than moderately obese women (P< or =0.05). After menopause, the metabolic profile of severely obese women, dysmetabolic or not, was similar to that of moderately obese women. Blood pressure was, however, higher in severely obese women compared to moderately obese women, only before menopause (P< or =0.0001). CONCLUSION: These results indicate that despite their large accumulation of adipose tissue, most of the severely obese women had a metabolic profile less deteriorated than expected, when compared to moderately obese women.

Adipose Tissue↗

Health-related quality of life in morbid obesity.

BACKGROUND: In order to evaluate the impact of severe obesity and its treatment on quality of life (QoL), it would be important to first identify the areas of QoL most likely to be affected by the disease. METHODS: We first constructed a list of 187 items potentially related to QoL of patients with morbid obesity. From this list, consecutive candidates for bariatric surgery were asked to identify what they felt were the most significant items and to grade their importance. The item impact was determined from the proportion of patients who identified it as important, and the mean importance score attributed to this item (impact score = frequency X importance). RESULTS: 100 patients (68 female; mean body mass index 51.5 kg/m(2); mean age 42) were interviewed. Overall, the impact of morbid obesity was more important in women than in men. The areas of impairment were very similar in both groups, with the important difference that women ranked their dissatisfaction with physical appearance higher than men. The items having the most important impact on QoL clustered into 7 domains: 1) activity/mobility; 2) symptoms; 3) personal hygiene/clothing; 4) emotions; 5) social interactions; 6) sexual life; and 7) eating behavior. CONCLUSION: The impact of morbid obesity on QoL is not limited to the activity/mobility domain. Morbid obesity contributes to the impairment of all domains of what is usually referred to as "health-related quality of life".

Adult↗

Increased plasma levels of toxic pollutants accompanying weight loss induced by hypocaloric diet or by bariatric surgery.

BACKGROUND: Weight loss reduces the risk of several diseases. Increases of plasma organochlorine and pesticide compounds, however, have been observed with weight loss induced by a dietary intervention and by a gastroplasty. This increased concentration of toxic pollutants could be a side-effect of weight loss and a risk for health problems. The aim of this study was: 1) to observe if there is a relationship between the plasma concentration of organochlorines and BMI at steady state weight, and 2) to determine, after a bariatric surgical intervention, if the magnitude of the weight loss has a direct effect on this concentration. METHODS: Weight loss was obtained in obese individuals by a hypocaloric diet program until resistance and in morbidly obese individuals by a bariatric operation (biliopancreatic diversion - duodenal switch [BPD-DS]). Normal-weight individuals were tested to serve as controls. Blood samples were analyzed for organochlorine and pesticide compounds at baseline in all groups, after resistance to weight loss in obese individuals, and at 3 months and 1 year after surgery in morbidly obese individuals. RESULTS: At steady state weight, organochlorine and pesticide compounds were found in all groups, and the sum of all organochlorine compounds correlated with age and not BMI. Weight loss averaged 12.1% of the initial body weight after dieting and 20.9% at 3 months after surgery, respectively. This weight loss yielded significant increases in total plasma organochlorine concentration (increase of 23.8% for obese and 51.8% for morbidly obese individuals). For morbidly obese individuals, the weight loss at 1 year after surgery (46.3%) yielded a 388.2% increase in total plasma organochlorine concentration. CONCLUSION: Plasma organochlorine concentration increases with weight loss and is related to the magnitude. Future research will have to determine if: 1) this pollutant concentration remains elevated over time and 2) there are long-term effects of this high concentration on health.

Adult↗

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

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, cross sectional 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.

Adolescent↗

Accelerated satiation after duodenal switch.

BACKGROUND: This is to introduce a new test "negative alliesthesia" for measuring satiation after bariatric surgery. It is a test that is well known by physiologists but has never been used clinically. It is based on the observation that repeated pleasant gustatory stimuli turn into unpleasantness in the process of satiation. METHODS: We measured the time it took for a repeatedly ingested sweet stimulus to become first unpleasant (negative alliesthesia) and then intolerable (satiety). At the same time, we measured the degree of pleasure aroused by the sweet stimulus (hedonic rating). The test was given to 9 patients before and 3 and 6 months after the duodenal switch procedure and in 10 morbidly obese patients, three times, 3 months apart. RESULTS: The test showed that negative alliesthesia and satiety were three times faster after surgery. The negative alliesthesia time decreased from 16.0 +/- 3.9 minutes to 5.7 +/- 1.4 minutes (P < 0.0004). The satiety time decreased from 26.7 +/- 5.0 minutes to 10.7 +/- 1.3 minutes (P <0.001). Finally, the hedonic rating for the sweet stimulus decreased from 78.8% +/- 15.7% to 49.9% +/- 13.0% at 3 months and 39.3% +/- 20.6% at 6 months after surgery, without, however, reaching statistical significance. CONCLUSION: The duodenal switch modified negative alliesthesia. It is too soon to say what place this test may have in bariatric surgery, but its simplicity and ingenuity are attractive.

Adult↗

Contribution of bariatric surgery to the comprehension of morbid obesity.

Convinced that morbid obesity was not due to food excess but rather to a metabolic disorder, we searched in the literature for data in favor of a metabolic disorder. We have found evidence in support of the thesis that the cause of morbid obesity is the inability to burn excessive caloric intake normally. It would involve the difficulty to increase heat with the amount of calories taken, which would be faulty and force fat deposition. This mechanism called dietinduced thermogenesis (DIT) allows the dispersion by heat of excessive calories to obtain energy balance. Results from bariatric surgery and particularly biliopancreatic diversion (BPD) give further support to this thesis. BPD would improve heat production to a meal (DIT) by one of these mechanisms: increased insulin sensitivity, change in intestinal hormone secretion, or chronic lipid malabsorption. Available results show that surgery, to be efficient, must change the physiology and not solely decrease food intake.

Basal Metabolism↗

Metabolic and cardiovascular improvements after biliopancreatic diversion in a severely obese patient.

BACKGROUND: Severe obesity is associated with important morbidity and increased mortality. The successes of lifestyle modifications and drug therapy have been partial and mostly unsustained in reducing obesity and its comorbidities. Bariatric surgery, particularly biliopancreatic diversion with duodenal switch reduces efficiently excess body weight and improves metabolic and cardiovascular functions. CASE PRESENTATION: A 56-year-old man with severe clinical obesity underwent a biliopancreatic diversion with a duodenal switch after unsuccessful treatment with weight loss pharmacotherapy. He had diabetes, hypertension and sleep apnea syndrome and was on three medications for hypertension and two hypoglycemic agents in addition to > 200 insulin units daily. Eleven months after the surgery, he had lost 40% of his body weight. The lipid profile showed great improvement and the hypertension and diabetes were more easily controlled with no more insulin needed. The pseudonormalized pattern of left ventricular diastolic function improved and ventricular walls showed decreased thickness. CONCLUSION: Biliopancreatic diversion may bring metabolic and cardiovascular benefits in severely obese patients from a cardiovascular perspective.

Journal Article↗

Effects of surgical treatment of the metabolic syndrome on liver fibrosis and cirrhosis.

BACKGROUND: Both weight loss and gastrointestinal surgery for obesity can cause liver disease, making their role in the treatment of obesity-related liver disease controversial. METHODS: Six hundred eighty-nine severely obese women (n=551) and men (n=138), BMI=47+/-9 kg.m(-2) (mean+/-SD), without known liver disease, underwent biliopancreatic diversion (BPD) with liver biopsy. Fourteen patients (2%) had cryptogenic cirrhosis, 11 of whom underwent multiple repeat biopsies. After 38+/-18 kg weight loss, 104 of the 689 patients underwent routine second biopsies during reoperations 41+/-25 months after BPD. All biopsy specimens were graded for steatosis, fibrosis, and inflammation by a blinded hepatopathologist. RESULTS: All 689 patients lost weight accompanied by improvements in the metabolic syndrome. Among the 104 patients who underwent reoperation, severe fibrosis (grade 3-5) decreased in 28 whereas mild fibrosis (grade 1-2) appeared in 42. Increased fibrosis was related to low-normal serum albumin, uncontrolled diarrhea, low intake of alcohol, and menopausal status. Fibrosis and inflammation decreased over time (P<.01). The 11 patients with cirrhosis exhibited decreased fibrosis from a mean grade 5 to grade 3, as well as reduced inflammation, Mallory bodies, and glycogenated nuclei. Seven patients had disappearance and 2 regression of nodules and fibrous bridging. CONCLUSIONS: The metabolic syndrome of obesity is a determinant of liver fibrosis and cirrhosis, treatable by substantial weight loss after malabsorptive surgery.

Adult↗

A survey of genes differentially expressed in subcutaneous and visceral adipose tissue in men.

Adipose tissue located within the abdominal cavity has been suggested to be functionally and metabolically distinct from that of the subcutaneous compartment. These differences could play a role in obesity-related complications. The aim of this study was to compare gene expression profiles of subcutaneous and visceral adipose tissues of 10 nondiabetic, normolipidemic obese men. Affymetrix human U133A arrays (10 arrays for subcutaneous fat samples and 10 arrays for visceral fat samples) were used. Differential gene expression was confirmed by real-time polymerase chain reaction in a subset of genes. A total of 5894 transcripts were detected in both depots in all 10 subjects, and 409 transcripts representing 347 encoded genes were differentially expressed. Of these, 131 genes were expressed at higher levels in subcutaneous adipose tissue, and 216 were expressed more abundantly in visceral fat. Differentially expressed profiles included genes of the Wnt signaling pathway, as well as CEPBA and HOX genes. In addition, genes involved in lipolytic stimuli and cytokine secretion were differentially expressed. The identification of a consistent and rather uniform pattern of differentially expressed genes between the two fat depots using multiple array replicates (10 arrays per fat compartment) generated new perspectives for future research on regional differences in adipose tissue biology.

Abdomen↗

Twenty years of biliopancreatic diversion: what is the goal of the surgery?

BACKGROUND: Comparative evaluation of weight loss after bariatric surgery is difficult without definition of success and without a norm for presenting results. We explored the pertinence of defining success: a residual BMI <40 or <35 kg/m(2), and the need for reporting results with stratification by initial obesity and length of follow-up. METHODS: Results of 1,271 consecutive biliopancreatic diversion (BPD) patients were compared when presented with or without stratification, and we searched for landmarks of success which would be shared by patients themselves. RESULTS: Presented globally, after a mean follow-up of 7.9 +/- 4.2 years, BMI decreased from 48.4 +/- 9.4 to 31.3 +/- 6.5, and only 10% and 26% of patients would have been considered failures with a residual BMI >or= 40 or >or= 35 respectively. Because heavier patients were losing less in terms of percentage ( P <0.0001) and regained weight faster ( P <0.0001), global and cumulative results failed to show a failure-rate doubling every 5 years and a very high failure-rate in heavier patients. The landmarks of BMI 40 and 35 were the same unconsciously used by patients to express their own perception of failure. For patients with an initial BMI <50, a residual BMI of 35 caused a significant drop in the degree of satisfaction from 90 to 40%. For super-obese, the same critical point was found at a BMI of 40 where satisfaction dropped from 91 to 57%. CONCLUSION: Landmarks of success at BMI 40 and 35 were realistic, reasonable and coincided with patients' own expectations. Since initial obesity and duration after surgery made so much difference in results, a comparison of different surgical approaches was useless without stratification for both factors together.

Adult↗

Outcome of pregnancies after biliopancreatic diversion.

BACKGROUND: Severe obesity has deleterious effects on fertility and pregnancy outcomes. Although surgery is the best long-term treatment for severe obesity, there is a risk of gestational undernutrition in operated mothers because bariatric surgery reduces nutrient availability. This is a follow-up report of our initial findings regarding pregnancy and neonatal outcomes in biliopancreatic diversion (BPD) patients, with addition of a new cohort of children born to mothers after BPD. METHODS: All women (n = 916) who had successfully undergone BPD in our hospital were mailed a questionnaire containing multiple-choice and essay questions concerning gynecologic and obstetric history, and pregnancy and neonatal outcomes in both preoperative and postoperative pregnancies. Patients operated between 1984 and 1995 (n = 568) were mailed an additional questionnaire regarding children's weight and height progress, and school performance. Perinatal records from our patients' obstetric clinics were also reviewed. RESULTS: The questionnaire was completed by 783 women (85.5%). 251 postoperative pregnancies in 132 women resulted in 166 infants by 109 mothers. 47.0% of patients who were unable to become pregnant preoperatively were successful postoperatively. 90 out of 109 women (82.6%) reported an appropriate weight gain (9.1 +/- 5.9 kg) during postoperative pregnancies. The incidence of fetal macrosomia decreased from 34.8 to 7.7%, with a concomitant increase in normal-weight babies from 62.1 to 82.7%. The elevated miscarriage rate (26.0%) in these obese women persisted after surgery. CONCLUSION: Major weight loss following BPD improves the reproductive function of severely obese women. BPD provides major beneficial effects for both mother and child, including normalization of gestational weight changes, reduction of fetal macrosomia, and normalization of the infant's birth-weight. Our results speak in favor of delaying pregnancy in obese women until after the substantial surgical weight loss has occurred.

Adolescent↗

Impact of bariatric surgery on cardiac structure, function and clinical manifestations in morbid obesity.

Obesity results from the excessive accumulation of fat. Risk of premature death is doubled compared to nonobese individuals, and risk of death from cardiovascular disease is increased fivefold. In patients with morbid obesity, a variety of adaptations and alterations in cardiac structure and function occur in the individual, as an excess amount of adipose tissue accumulates. The high long-term failure rate of diet intervention is well acknowledged by the clinician. Surgery for severe obesity has evolved during the last 40 years. Many surgical techniques have been described and abandoned. Nevertheless, numerous different techniques are still in use today. Weight loss has beneficial impacts on functional and structural cardiac status and will be reviewed in this report.

Body Weight↗

Effects of the peroxisome proliferator-activated receptor-gamma co-activator-1 Gly482Ser variant on features of the metabolic syndrome.

Factors influencing the severity of the metabolic syndrome among obese subjects or the conversion to cardiovascular disease or type 2 diabetes (T2D) remain largely unknown, but there is strong evidence for genetic susceptibilities. Peroxisome proliferator-activated receptor-gamma co-activator-1 (PPARGC1) is a transcriptional co-activator of many nuclear receptors including PPAR-gamma, involved in the regulation of fatty acid oxidation, skeletal muscle fiber type specificity, and gluconeogenesis. Given the critical role of PPARGC1, it becomes a promising candidate gene for the metabolic syndrome and T2D. This study aimed to investigate whether genetic variations in human PPARGC1 gene are associated with metabolic syndrome-related phenotypes and T2D among obese subjects. Molecular screening of the PPARGC1 gene in 24 morbidly obese French-Canadians revealed 13 variants. Eight genetic variations were in introns: c.55-27T>A, c.234+52C>A, c.553-40A>G, c.553-11T>C, c.757+161T>C, c.1793+19C>G, c.2141+192G>A, and c.2293+146A>G, and five were in coding regions: Thr394Thr, Asp475Asp, Gly482Ser, Thr528Thr, and Thr612Met with a relative allele frequency of 18.5, 5.2, 37.0, 42.5, and 6.8%, respectively. Thr394Thr, Asp475Asp, and Thr528Thr were in linkage disequilibrium with the Gly482Ser variant, the only non-synonymous variant with a relative allele frequency of more than 10%. Association studies were performed with the Gly482Ser variant. In non-diabetics, we compared between genotype differences in metabolic syndrome-related traits (waist girth, SBP, DBP, triglycerides, HDL-cholesterol (C), and fasting glucose levels). There was a difference in mean plasma HDL-C concentrations, the Gly/Gly group had lower concentrations than the Gly/Ser group (P<0.05). These results suggest that the Gly482Ser polymorphism may explain some of the between-obese variance observed in metabolic syndrome-related traits.

Base Sequence↗

Does bone change after biliopancreatic diversion?

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-OH(2)-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-OH(2)-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.

25-Hydroxyvitamin D 2↗