Risk of pre-eclampsia after gastric bypass: a matched cohort study.

OBJECTIVE: To investigate whether gastric bypass before pregnancy is associated with reduced risk of pre-eclampsia. DESIGN: Nationwide matched cohort study. SETTING: Swedish national health care. POPULATION: A total of 843 667 singleton pregnancies without pre-pregnancy hypertension were identified in the Swedish Medical Birth Register between 2007 and 2014, of which 2930 had a history of gastric bypass and a pre-surgery weight available from the Scandinavian Obesity Surgery Registry. Two matched control groups (pre-surgery and early-pregnancy body mass index [BMI]) were propensity score matched separately for nulliparous and parous births, to post-gastric bypass pregnancies (npre-surgery-BMI = 2634:2634/nearly-pregnancy-BMI = 2766:2766) on pre-surgery/early-pregnancy BMI, diabetes status (pre-surgery/pre-conception), maternal age, early-pregnancy smoking status, educational level, height, country of birth, delivery year and history of pre-eclampsia. MAIN OUTCOME MEASURES: Pre-eclampsia categorised into any, preterm onset (<37+0 weeks) and term onset (≥37+0 weeks). RESULTS: In post-gastric bypass pregnancies, mean pre-surgery BMI was 42.9 kg/m2 and mean BMI loss between surgery and early pregnancy was 14.0 kg/m2 (39 kg). Post-gastric bypass pregnancies had lower risk of pre-eclampsia compared with pre-surgery BMI-matched controls (1.7 versus 9.7 per 100 pregnancies; hazard ratio [HR] 0.21, 95% CI 0.15-0.28) and early-pregnancy BMI-matched controls (1.9 versus 5.0 per 100 pregnancies; HR 0.44, 95% CI 0.33-0.60). Although relative risks for pre-eclampsia for post-gastric bypass pregnancies versus pre-surgery matched controls was similar, absolute risk differences (RD) were significantly greater for nulliparous women (RD -13.6 per 100 pregnancies, 95% CI -16.1 to -11.2) versus parous women (RD -4.4 per 100 pregnancies, 95% CI -5.7 to -3.1). CONCLUSION: We found that gastric bypass was associated with lower risk of pre-eclampsia, with the largest absolute risk reduction among nulliparous women. TWEETABLE ABSTRACT: In this large study including two comparison groups matched for pre-surgery or early-pregnancy BMI, gastric bypass was associated with lower risk of pre-eclampsia.

Fracture risk after three bariatric surgery procedures in Swedish obese subjects: up to 26 years follow-up of a controlled intervention study.

BACKGROUND: Previous studies have reported an increased fracture risk after bariatric surgery. OBJECTIVE: To investigate the association between different bariatric surgery procedures and fracture risk. METHODS: Incidence rates and hazard ratios for fracture events were analysed in the Swedish Obese Subjects study; an ongoing, nonrandomized, prospective, controlled intervention study. Hazard ratios were adjusted for risk factors for osteoporosis and year of inclusion. Information on fracture events were captured from the Swedish National Patient Register. The current analysis includes 2007 patients treated with bariatric surgery (13.3% gastric bypass, 18.7% gastric banding, and 68.0% vertical banded gastroplasty) and 2040 control patients with obesity matched on group level based on 18 variables. Median follow-up was between 15.1 and 17.9 years for the different treatment groups. RESULTS: During follow-up, the highest incidence rate for first-time fracture was observed in the gastric bypass group (22.9 per 1000 person-years). The corresponding incidence rates were 10.4, 10.7 and 9.3 per 1000 person-years for the vertical banded gastroplasty, gastric banding and control groups, respectively. The risk of fracture was increased in the gastric bypass group compared with the control group (adjusted hazard ratio [adjHR] 2.58; 95% confidence interval [CI] 2.02-3.31; P < 0.001), the gastric banding group (adjHR 1.99; 95%CI 1.41-2.82; P < 0.001), and the vertical banded gastroplasty group (adjHR 2.15; 95% CI 1.66-2.79; P < 0.001). CONCLUSIONS: The risk of fracture is increased after gastric bypass surgery. Our findings highlight the need for long-term follow-up of bone health for patients undergoing this treatment.

Outcomes of laparoscopic gastric bypass in a randomized clinical trial compared with a concurrent national database.

BACKGROUND: RCTs are the standard for assessing medical interventions, but they may not be feasible and their external validity is sometimes questioned. This study aimed to compare results from an RCT on mesenteric defect closure during laparoscopic gastric bypass with those from a national database containing data on the same procedure, to shed light on the external validity of the RCT. METHODS: Patients undergoing laparoscopic gastric bypass surgery within an RCT conducted between 1 May 2010 and 14 November 2011 were compared with those who underwent the same procedure in Sweden outside the RCT over the same time interval. Primary endpoints were severe complications within 30 days and surgery for small bowel obstruction within 4 years. RESULTS: Some 2507 patients in the RCT were compared with 8485 patients in the non-RCT group. There were no differences in severe complications within 30 days in the group without closure of the mesenteric defect (odds ratio (OR) for RCT versus non-RCT 0·94, 95 per cent c.i. 0·64 to 1·36; P = 0·728) or in the group with closure of the defect (OR 1·34, 0·96 to 1·86; P = 0·087). There were no differences between the RCT and non-RCT cohorts in reoperation rates for small bowel obstruction in the mesenteric defect non-closure (cumulative incidence 10·9 versus 9·4 per cent respectively; hazard ratio (HR) 1·20, 95 per cent c.i. 0·99 to 1·46; P = 0·065) and closure (cumulative incidence 5·7 versus 7·0 per cent; HR 0·82, 0·62 to 1·07; P = 0·137) groups. The relative risk for small bowel obstruction without mesenteric defect closure compared with closure was 1·91 in the RCT group and 1·39 in the non-RCT group. CONCLUSION: The efficacy of mesenteric defect closure was similar in the RCT and national registry, providing evidence for the external validity of the RCT.

Formation of the Scandinavian Obesity Surgery Registry, SOReg.

BACKGROUND: Obesity surgery is expanding, the quality of care is ever more important, and learning curve assessment should be established. A large registry cohort can show long-term effects on obesity and its comorbidities, complications, and long-term side effects of surgery, as well as changes in health-related quality of life (QoL). Sweden is ideally suited to the task of data collection and audit, with universal use of personal identification numbers, nation-wide registries permitting cross-matching to analyze causes of death, in-hospital care, and health-related absenteeism. METHOD: In 2004, the Scandinavian Obesity Surgery Registry (SOReg) was initiated and government financing secured. A project group created a national database covering all public as well as private hospitals. Data entry was to be made online, operative definitions of comorbidity were formed, and complication severity scored. Several forms of audit were devised. RESULTS: After pilot studies, the system has been running in its present form since 2007. Since 15 January 2013, SOReg covers all bariatric surgery centers in Sweden. The number of operations in the database exceeded 40,000 (March 2014), with a median follow-up of 2.94 years. Audit shows that >98% of data are correct. All results are publicized annually on the Internet. COMMENTS: Using this systematic approach, it has been possible to cover >99% of all bariatric surgery, cross-matching our data with nation-wide registries for in-hospital care, cause of death, and permitting regular nation-wide audit. Several scientific studies have used, or are using, what seems to be the most comprehensive database in obesity surgery.

Body composition through adult life: Swedish reference data on body composition.

BACKGROUND/OBJECTIVES: The prevalence of obesity, defined as body mass index (BMI) ⩾30 kg/m(2), differs between populations; however, there is a need for data on description on body composition in reference populations of different ages and from different countries. The objective of this study was to pool dual-energy X-ray absorptiometry (DXA) body composition reference data from population-based Swedish cohorts. SUBJECTS/METHODS: Four population-based cross-sectional cohort studies including 1424 adult Swedes were divided into five age groups (20-29, 30-39, 40-49, 50-61 and 75 years of age); BMI 24.6±3.9 kg/m(2) were pooled. Body composition was measured with DXA. RESULTS: The difference in BMI from the youngest to the oldest age group was 3.2 and 4.3 kg/m(2) in men and women, respectively (P<0.001, both sexes), and fat mass (FM) was 9.9 and 9.1% higher in the oldest compared with the youngest men and women (P<0.001, both sexes). Fat-free mass (FFM) remained stable up to 60 years of age in men (P=0.83) and was lower at 75 years of age compared with the younger ages. In women, FFM was lower from age 60. From youngest to oldest age groups, height-adjusted FM differed from 4.6 to 7.8 kg/m(2) in men and from 6.8 to 10.8 kg/m(2) in women (P<0.001, both sexes). CONCLUSIONS: Our results provide reference data on body composition in Swedish populations. BMI and FM were higher among older age groups compared with the younger ones. FFM remained stable up to 60 years of age and was lower first among the 75 years of age.

Budget impact analysis of surgical treatment for obesity in Sweden.

BACKGROUND: The recent substantial increase in the number of obese surgeries performed in Sweden has raised concerns about the budget impact. OBJECTIVE: Our aim in this paper is to present an assessment of the budgetary impact of different policies for surgical intervention for obese and overweight subjects from a healthcare perspective in Sweden. METHODS: The model simulates the annual expected treatment costs of obesity related diseases and surgery in patients of different sex, age and Body Mass Index (BMI). Costs evaluated are costs of surgery plus the excess treatment costs that an obese patient has over and above the treatment costs of a normal-weight patient. The diagnoses that are included for costs assessment are diabetes and cardiovascular disease since these diagnoses are the principal diagnoses associated with obesity. Four different scenarios over the number of surgical operations performed each year are simulated and compared: (1) no surgical operation, (2) 3 000 surgical operations in persons with BMI > 40, (3) 4 000 (BMI > 40), and (4) 5 000 (expanded to BMI > 38). RESULTS: Comparing Scenario 2 with Scenario 1 results in a net budget impact of on average SEK 121 million per annum or SEK 40 000 per patient. This implies that 55 percent of the cost of surgery, set equal to SEK 90 000 for each patient, has been offset by a reduction in the excess treatment costs of obesity related diseases. Expanding annual surgery from 3000 to 4000 the cost-offset increased to 58%. By expanding annual surgery further from 4000 to 5000 and at the same time expanding the indication for surgery from BMI > 40 to BMI > 38, no cost-offset is obtained. CONCLUSION: A cost-minimization strategy for bariatric surgery in Sweden should not expand indication, but rather increase the number of surgeries within the currently accepted indication.

Thermal growth performance of juvenile brown trout Salmo trutta: no support for thermal adaptation hypotheses.

Using thermal growth data from eight populations of anadromous and lake-feeding brown trout Salmo trutta, hypotheses of adaptation to local optima and countergradient variation in growth were tested. The adaptation to local optima hypothesis suggests that natural selection can shift optimal performance temperatures to match the prevailing temperature in a new or changed thermal niche. In contradiction, the countergradient variation hypothesis suggests that populations from hostile environments perform better than conspecifics from benign environments at all temperatures. In this study, growth capacity varied between populations but there was no significant correlation between any of the estimated thermal performance parameters (e.g. lower and upper thermal growth limits, optimal temperature for growth and maximum growth capacity) and natural climatic conditions among populations. Hence, S. trutta growth response to temperature lends no support for either of the two suggested thermal adaptation hypotheses. Instead, growth capacity among populations tended to correlate positively with female size at maturity.

Overall obesity, abdominal adiposity, diabetes and cigarette smoking in relation to the risk of pancreatic cancer in two Swedish population-based cohorts.

We examined the associations of body mass index (BMI), waist circumference, a history of diabetes, and cigarette smoking with risk of pancreatic cancer among 37,147 women and 45,906 men followed up during 560,666 person-years in the Swedish Mammography Cohort and the Cohort of Swedish Men; 136 incident cases of pancreatic cancer were diagnosed. The multivariate rate ratio (RR) of pancreatic cancer for obese women and men (BMI > or =30 kg/m(2)) was 1.81 (95% CI: 1.04-3.15) compared to those with a BMI of 20-25 kg/m(2). For a difference of 20 cm (about two standard deviations) in waist circumference, the multivariate RRs were 1.32 (95% CI: 0.73-2.37) among women and 1.74 (95% CI: 1.00-3.01) among men. Pancreatic cancer risk was associated with history of diabetes (multivariate RR: 1.88; 95% CI: 1.09-3.26) and cigarette smoking (multivariate RR for current compared with never smokers: 3.06; 95% CI: 1.99-4.72). Current smokers of > or =40 pack-years had a five-fold elevated risk compared with never smokers. Risk among past smokers approached the RR for never smokers within 5-10 years following smoking cessation. Findings from this prospective study support positive relationships of overall obesity, abdominal adiposity, diabetes and smoking with risk of pancreatic cancer.

Body composition in the SOS (Swedish Obese Subjects) reference study.

OBJECTIVE: The primary objective was to establish population-based, sex- and age-specific reference data with respect to body composition variables. Secondary objectives were to relate body mass index (BMI) to anthropometric measurements reflecting central adiposity and to body fat (BF). Another objective was to examine if secular changes in adipose tissue distribution occurred during the sampling period, 1994-1999. DESIGN: Sex- and age-specific data on anthropometric measurements and body composition were cross-sectionally collected in the reference study of Swedish Obese Subjects. SUBJECTS: In total, 1135 randomly selected subjects (524 men and 611 women), aged 37-61 y, BMI 17.6-45.4 kg/m(2). MEASUREMENTS: Measures of body fatness and fat distribution (by dual energy X-ray absorptiometry and anthropometry) were collected. RESULTS: At BMI 25 kg/m(2), relative (absolute) BF mass was 24% (19 kg) in men vs 36% (25 kg) in women, waist circumference was 90 vs 85 cm, and sagittal trunk diameter was 21 vs 19 cm. BF and measures of centralized adipose tissue distribution increased with age in both sexes (P<0.01). In women, waist circumference and sagittal diameter increased (P<0.01) over the sampling period while BMI did not. CONCLUSIONS: Sex- and age-specific reference data on body composition are reported from a randomly selected sample of Swedish men and women. At given BMIs, women had more BF but smaller waist circumference than men. Secular increases in indices of central obesity were found in women but not in men.

Faster absorption of ethanol and higher peak concentration in women after gastric bypass surgery.

AIMS: To investigate the absorption, distribution and elimination of ethanol in women with abnormal gut as a result of gastric bypass surgery. Patients who undergo gastric bypass for morbid obesity complain of increased sensitivity to the effects of alcohol after the operation. METHODS: Twelve healthy women operated for morbid obesity at least 3 years earlier were recruited. Twelve other women closely matched in terms of age and body mass index (BMI) served as the control group. After an overnight fast each subject drank 95% v/v ethanol (0.30 g kg-1 body weight) as a bolus dose. The ethanol was diluted with orange juice to 20% v/v and finished in 5 min. Specimens of venous blood were taken from an indwelling catheter before drinking started and every 10 min for up to 3.5 h post-dosing. The blood alcohol concentration (BAC) was determined by headspace gas chromatography. RESULTS: The maximum blood-ethanol concentration (Cmax) was 0.741 +/- 0.211 g l-1 (+/- s.d.) in the operated group compared with 0.577 +/- 0.112 g l-1 in the controls (mean difference 0.164 g l-1, 95% confidence interval (CI) 0.021, 0.307). The median time to peak (tmax) was 10 min in the bypass patients compared with 30 min in controls (median difference -15 min (95% CI -10, -20 min). At 10 and 20 min post-dosing the BAC was higher in the bypass patients (P < 0.05) but not at 30 min and all later times (P > 0.05). Other pharmacokinetic parameters of ethanol were not significantly different between the two groups of women (P > 0.05). CONCLUSIONS: The higher sensitivity to ethanol after gastric bypass surgery probably reflects the more rapid absorption of ethanol leading to higher Cmax and earlier tmax. The marked reduction in body weight after the operation might also be a factor to consider if the same absolute quantity of ethanol is consumed.

Perioperative gastric emptying is not a predictor of early postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy.

UNLABELLED: It is not known whether patients with postoperative nausea and vomiting (PONV) have delayed gastric emptying compared with patients without PONV. We compared the perioperative rate of gastric emptying in patients experiencing PONV with the rate in those without PONV immediately after laparoscopic cholecystectomy. Gastric emptying was studied by the acetaminophen method. Acetaminophen is not absorbed from the stomach but is rapidly absorbed from the small intestine, and the rate of gastric emptying therefore determines the rate of absorption of acetaminophen administered into the stomach. Forty patients (ASA physical status I and II) were included in the study. After the induction of anesthesia, a gastric tube was positioned in the stomach and 1.5 g of acetaminophen dissolved in 200 mL of water was administered. Venous blood samples for the determination of serum acetaminophen concentrations were taken before and at 15-min intervals during a period of 180 min after the administration of acetaminophen. Twenty-six patients experienced nausea during the first 4 h postoperatively. The other 14 patients had no nausea. There were no statistically significant differences in the maximal acetaminophen concentration, the time taken to reach the maximal concentration, or the area under the serum acetaminophen concentration time curves from 0 to 60, 0-120, and 0-180 min between the groups of patients with or without PONV. We did not find any relationship between postoperative gastric emptying and PONV, and therefore gastric emptying is not a predictor of PONV. IMPLICATIONS: The incidence of postoperative nausea and vomiting is frequent after laparoscopic cholecystectomy. This study has shown that perioperative gastric emptying is not a predictor of early postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy.

Long-term effects of weight loss on pharmaceutical costs in obese subjects. A report from the SOS intervention study.

BACKGROUND: Although intentional weight reduction improves obesity-related comorbidities, the associations between weight reduction, medication and related costs are rarely studied. This study investigates the long-term effects of weight change on medication for diabetes and cardiovascular disease (CVD) in severely obese subjects. METHODS: In the intervention study Swedish Obese Subjects, 510 surgically and 455 conventionally treated obese patients have so far been followed for 6 y. Changes in the use and costs of medication were analyzed in relation to treatment and weight change. RESULTS: In comparison with controls, larger fraction of surgically treated patients discontinued the use of medication for CVD and diabetes at 2 and 6 y (risk ratios 0.56-0.77). Among subjects not initially on medication, surgery reduced the frequency of started treatments (risk ratios 0.08-0.80). Relative weight loss >or=10% was necessary to reduce costs of medication for CVD and diabetes among subjects with such treatment at baseline. To reduce initiation of new treatment against the two conditions, weight loss >or=15% was required. Over 6 y, the average annual cost for diabetes and CVD medication increased by 463 SEK (96%) in subjects with weight loss <5%, and decreased by 39 SEK(8%) in the weight loss group >or=15%. CONCLUSION: Long-term intentional weight loss is associated with reduced medication and medication costs for diabetes and CVD. The effects appear to be more marked among subjects who are initially on medication for these conditions, whereas greater weight reduction is needed to prevent new subjects from starting on medication.

Effects of information supply on satisfaction with information and quality of life in cancer patients receiving curative radiation therapy.

In order to test the efficacy of various information inputs, 210 consecutive cancer patients were randomized to one of three information conditions before the start of curative radiation treatment: (1) standard information plus group and repeated individual information (n=70), (2) standard information plus brochure (n=70), and (3) standard information only (n=70). Patients completed questions regarding satisfaction with information, anxiety, depression, subjective distress and quality of life at inclusion, and 1h before the start of the radiation therapy treatment (approximately 4 weeks later). Patients receiving standard information plus group and repeated individual information were significantly more satisfied with the information than were patients in the remaining two groups. There were no differences with respect to any of the other outcome measures. This study has shown that the nurses group and individual information was of significant importance in preparing the patients for the procedure of receiving radiation therapy.

Can 8-oxo-dG be used as a predictor for individual radiosensitivity?

PURPOSE: To develop predictive tests for individual radiosensitivity of tumor patients. METHODS AND MATERIALS: Acute skin reactions were clinically scored among 40 women after 46 Gy, given with 2 Gy fractions to breast and regional lymph nodes, adjuvant after surgery. The acute skin reactions were compared to the excretion of 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dG) in urine, determined by high-performance liquid chromatography (HPLC) with electrochemical detector. Specimens of urine were collected before and during postoperative radiation treatment at given intervals. We compared a group of 9 patients with the most pronounced skin reactions with another group of 8 patients with almost no skin reactions at 46 Gy. RESULTS: The level of 8-oxo-dG excreted in urine during 8 h was measured. After normalizing the excretion to irradiated volumes, dose per volume and excretion before irradiation, the 8-oxo-dG level in urine was significantly (p < 0.001) lower for the patients with pronounced skin reactions as compared to patients with minor skin reactions, at an accumulated dose of 12 Gy. In addition, the background level of 8-oxo-dG excreted before treatment started, was significantly (p = 0.043) lower for patients with minor skin reactions as compared to patients with pronounced skin reactions. The background level of 8-oxo-dG was corrected for body weight and normalized to BMI. CONCLUSION: We suggest that the excretion of 8-oxo-dG into urine of breast cancer patients is a possible marker for acute radiosensitivity.

Electrochemical treatment of tumours.

The electrochemical treatment (EChT) of tumours implies that tumour tissue is treated with a continuous direct current through two or more electrodes placed in or near the tumour. The treatment offers considerable promise of a safe, simple and relatively noninvasive anti-tumour therapy for treatment of localised malignant as well as benign tumours. Although more than 10,000 patients have been treated in China during the past 10 years, EChT has not yet been universally accepted. The reason for this is the lack of essential preclinical studies and controlled clinical trials. Uncertainties regarding the destruction mechanism of EChT also hinder the development of an optimised and reliable dose-planning methodology. This article reviews the collected Chinese and occidental experiences of the electrochemical treatment of tumours, alone and in combination with other therapies. The current knowledge of the destruction mechanism underlying EChT is presented along with different approaches towards a dose planning methodology. In addition, we discuss our view of different important parameters that have to be accounted for, if clinical trials are to be initiated outside of China.

NO and de novo mammalian angiogenesis: further evidence that NO inhibits bFGF-induced angiogenesis while not influencing VEGF165-induced angiogenesis.

Using the non-surgical rat mesenteric window angiogenesis assay, we studied the systemic effect of (i) the nitric oxide (NO)-releasing vasodilator isosorbide-5-mononitrate (ISMN) and (ii) the NO-synthase inhibitor L-NAME on angiogenesis induced by the intraperitoneal injection of bFGF and VEGF165. The response was assessed objectively and quantitatively by microscopic morphometry and image analysis in terms of the vascularized area (VA; a measurement of microvessel spatial extension), the microvascular length (MVL; a composite measurement of microvessel density), the total microvascular length (TMVL=VA x MVL), the number of microvessel segments per unit tissue volume (No. MS), the length of the microvessel segments (Le. MS) and the degree of microvessel tortuosity (MVT). Additional architectural features of the network were assessed in terms of variables introduced here: the number of microvessel branching points per unit tissue volume (No. BP), the index of interconnecting microvessel loop formation (In. LF), the index of microvessel intersection (In. IS), the number of microvessel sprouts per unit tissue volume (No. SP) and their length (Le. SP). In bFGF-mediated angiogenesis, L-NAME significantly, augmented angiogenesis, whereas ISMN significantly inhibited angiogenesis. By contrast, neither L-NAME nor ISMN affected the angiogenic response to VEGF165.

Sick leave and disability pension before and after treatment for obesity: a report from the Swedish Obese Subjects (SOS) study.

OBJECTIVES: To analyse sick leave and disability pension among surgically and conventionally treated obese patients. DESIGN: A prospective study over five years. Differences in sick leave and disability pension were analysed using multiple and logistic regressions. Possible confounding factors were analysed and controlled for. SETTING: Nine counties in Sweden. SUBJECTS: 369 surgically treated patients and 371 matched obese controls, included in the Swedish Obese Subjects (SOS) study. At baseline, mean body mass index (BMI) was 42 kg/m2 in surgical patients and 41 kg/m2 in controls. After four years of treatment, weight reduction was 20% among surgical patients while the control patients kept their initial weight. INTERVENTION: Gastric bariatric surgery. MEASUREMENTS: Days of sick leave plus disability pension, and days of disability pension. RESULTS: In the year prior to treatment, adjusted average number of days of sickness due to sick leave plus disability pension was similar in surgical patients and controls. Compared with controls, the surgical group had 35% more days of sickness during the first year after initiation of treatment, but 10-14% fewer days during years 2-3. During year four, days of sickness tended to be lower in the surgical group (P = 0.07). In the sub-group, aged above the median, surgical patients had 14-18% fewer days of sickness than controls, during years 2-3 after initiation of treatment This difference did not occur in the group below median age. CONCLUSION: Surgical treatment of obesity results in a reduction of sick leave and disability pension, compared to controls, particularly in subjects aged 47-60 y.

DNA polymorphism in the uncoupling protein 1 (UCP1) gene has no effect on obesity related phenotypes in the Swedish Obese Subjects cohorts.

OBJECTIVE: To investigate the relationships between the A-G point mutation at position -3826 bp in the 5' flanking domain of the uncoupling protein 1 (UCP1 A-3826G) and some obesity phenotypes in the Swedish Obese Subjects (SOS) cohorts of obese and non-obese men and women. Previous studies have supported the hypothesis of an association between the UCP1 A-3826G polymorphism and body weight regulation in humans. DESIGN: Case-control study comparing obese subjects from the SOS registry and a sample of the Swedish general population (body mass index (BMI) <27 kg/m2) with respect to genotype and allele frequencies of the UCP1 A-3826G polymorphism. SUBJECTS: A total of 985 Swedish subjects including 674 obese (310 Male; 364 Female) and 311 non-obese subjects (54 Male; 257 Female) from the SOS cohorts. MEASUREMENTS: DNA was extracted from total blood and genotyped by PCR-RFLP. Obesity-related phenotypes include weight history for SOS obese cohort and current weight, BMI, waist circumference and waist to hip ratio (WHR) for obese and normal weight subjects. RESULTS: No significant difference in the allelic frequencies between obese and non-obese subjects (0.25 vs 0.24; P = 0.67). In both genders, current weight, BMI, waist circumference, WHR and weight gain over time (either measures of maximal weight ever achieved minus weight at 20 y or current weight minus weight at 20 y) were similar in carriers and non-carriers of the UCP1 A-3826G mutation (P>0.05). Similar results were obtained when the three genotypes were compared. CONCLUSIONS: In contrast to what was found in other populations, the UCP1 A-3826G sequence variation is not associated with obesity-related phenotypes and weight gain over time in subjects from the SOS cohorts.