Increases in morbid obesity in the USA: 2000-2005

Sexual function in male patients with metabolic syndrome and effective parameters on erectile dysfunction

PURPOSE

We aimed to investigate the relationship between metabolic syndrome and sexual function and effective parameters on erectile dysfunction (ED).

MATERIALS AND METHODS

A total of 1300 individuals were included in this study betwe¬en January 2009 and July 2012. All of individuals were asked to fill in an International Index for Erectile Function (IIEF) questionnaire. The presence of metabolic syndrome was determined when any three or more of the five risk factors were present according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP)-III. Obese individuals were divided into six groups according to modified World Health Organization (WHO) definition. Effective parameters on erectile dysfunction were investigated in individuals with metabolic syndrome.

RESULTS

Metabolic syndrome was detected in 455 individuals (35%). Mean domain scores of IIEF for all parameters were higher in individuals without metabolic syndrome than individuals with metabolic syndrome (p < 0.05). Mean domain scores of IIEF were lower in individuals with class 3 obesity than individuals with other obese groups (p < 0.05) for erectile dysfunction. There was statistical difference in terms of mean score of IIEF-Erectile function between smoking and nonsmoking groups (p < 0.05). Seventy percent of individuals with metabolic syndrome and 45% of individuals without metabolic syndrome had ED (p < 0.001). Logistic regression analysis revealed that waist circumference (WC) was the most important criteria for ED (p < 0.05).

CONCLUSIONS

Metabolic syndrome, smoking and obesity seem to be potential risk factors for ED. We recommend individuals with metabolic syndrome, smoking and obesity should be questioned about ED.

Bladeless direct optical trocar insertion in laparoscopic procedures on the obese patient

Results of the study suggest that direct optical entry technique reduced entry time and blood loss with trends to slightly decrease the occurrence of minor vascular and bowel injuries in obese women.

Background:

Recently, we have shown advantages of a direct optical entry (DOE) using a bladeless trocar in comparison with the open Hasson technique (OHT) in older reproductive-age women with previous operations, as well as in comparison with Veress needle entry in reproductive-age and postmenopausal women.

Objectives:

A prospective multicenter randomized study to determine whether the DOE is feasible for establishing safe and rapid entry into the abdomen in comparison with those of the OHT in reproductive-age obese women.

Methods:

Two types of surgical techniques were blindly applied in 224 obese reproductive-age women with benign neoplastic diseases of ovary and uterus. Namely, laparoscopic entry into the abdomen in 108 patients was performed by DOE and in 116 women by OHT. Following parameters (entry time in seconds needed to establish the intra-abdominal vision after pneumoperitoneum, blood loss, occurrence of vascular and/or bowel injuries) were compared during surgery as main outcomes.

Results:

Main baseline characteristics of patients, including age (36.1 ± 4.5 vs 35.7 ± 5.8), body mass index (34.9 ± 5.1 vs 35.1 ± 4.9 kg/m²), and parity (2.1 ± 0.4 vs 1.9 ± 0.9), were not significantly different between the DOE and OHT groups (P > .05). While intraoperative parameters such as the entry time (71.9 ± 3.7 vs 215.1 ± 6.2 seconds) and blood loss value (9.7 ± 6.1 vs 12.2 ± 2.9 mL) were significantly reduced in the DOE group in comparison with those of OHT group (respectively, P < .0001 and < .01), there were also trends to slight decrease of the occurrence of the minor injuries, manifested as omental small vessels rupture (0 of 108 vs 4 of 116) and punctures and pinches of jejunal serosa (0 of 108 vs 3 of 116) in patients of the DOE group in comparison with those of OHT group (respectively, P = .0515 and = .0925).

Conclusions:

DOE reduced entry time and blood loss with trends to slightly decrease of the occurrence of the minor vascular and bowel injuries, thus enabling a possible alternative to OHT in obese women; however, further larger trials need to confirm the possible additional benefits of a DOE.

Impact of physical activity and fitness in class II and III obese individuals: a systematic review

The objective of this systematic review was to appraise current knowledge on the impact of physical activity (PA) and physical fitness (PF) on the health of class II and III obese subjects and bariatric surgery (BS) patients. All original studies were searched using four databases (Medline®, Scopus®, CINAHL and Sportdiscus). Two independent investigators selected studies assessing the impact of PA or PF on specific health outcomes (anthropometric parameters, body composition, cardiometabolic risk factors, PF, wellness) in adults with a body mass index ≥35 kg m(-2) or in BS patients. Conclusions were drawn based on a rating system of evidence. From 3,170 papers identified, 40 papers met the inclusion criteria. The vast majority of studies were recently carried out with a predominance of women. Less than one-third of these studies were experimental and only three of them were of high quality. Each study reported at least one beneficial effect of PA or PF. However, a lack of high-quality studies and heterogeneity in designs prevented us from finding high levels of evidence. In conclusion, although results support the importance of PA and PF to improve the health of this population, higher-quality trials are required to strengthen evidence-based recommendations.

Factors and associations for physical activity in severely obese adults during a two-year lifestyle intervention

Objective. This study of severely obese adults participating in a two-year lifestyle intervention investigates associations between the independent variables: change in self-efficacy for physical activity (PA) in the face of psychological barriers, perceived behavioural control over PA, and PA self-identity and the dependent variable of change in objectively assessed PA. The intervention comprised four residential periods in a rehabilitation centre and combined diet, physical activity, and cognitive behavioural therapy.

Materials and Methods. Forty-nine severely obese adults (37 women, mean body mass index 42.1 kg/m²) were included in the study. Assessment was done four times using questionnaires and an accelerometer. A linear mixed model based on restricted maximum likelihood was used in analyses for change over time. Associations were studied using linear regression analyses. Age, gender, and change in body mass index were used as control variables.

Results. In the adjusted analyses, change in perceived behavioural control over PA was associated with change in PA (Stand. coeff. = 0.32, p = .005). Change in PA was not associated with either change in self-efficacy over PA in the face of psychological barriers (Stand. coeff. = 0.13, p = .259) or PA self-identity (Stand. coeff. = −0.07, p = .538).

Conclusion. Perceived behavioural control may be a valid target to increase and maintain PA in severely obese adults participating in lifestyle interventions. More research is needed to investigate the process of behaviour change in this population.

Multiple epidural steroid injections and body mass index linked with occurrence of epidural lipomatosis: a case series

Background

Epidural lipomatosis (EL) is an increase of adipose tissue, normally occurring in the epidural space, sufficient to distort the thecal sac and compress neural elements. There is a lack of knowledge of risk factors, impact on patient’s symptoms, and its possible association with epidural steroid injections.

Methods

History, physical examination, patient chart, and MRI were analyzed from 856 outpatients referred for epidural steroid injections. Seventy patients with signs of EL on MRI comprised the study group. Thirty-four randomly selected patients comprised the control group. The severity of EL was determined by the MRI assessment. The impact of EL was determined by the patient’s history and physical examination. Logistic regression was used to correlate the probability of developing EL with BMI and epidural steroid injections.

Results

EL was centered at L5 and S1 segments. The average BMI for patients with EL was significantly greater than that of control group (36.0 ± 0.9 vs. 29.2 ± 0.9, p <0.01). The probability of developing EL with increasing BMI was linear up to the BMI of 35 after which it plateaued. Triglycerides were significantly higher for the EL group as compared to controls (250 ± 30 vs. 186 ± 21 mg/dL p < 0.01). The odds of having EL were 60% after two epidural steroid injections, 90% after three epidural steroid injections and approached 100% with further injections, independent of BMI. Other risk factors considered included alcohol abuse, use of protease inhibitors, levels of stress, hypothyroidism and genetic predisposition. However there were insufficient quantities to determine statistical significance with a degree of confidence. The impact of EL on patient’s symptoms correlated with EL severity with Spearman correlation coefficient of 0.73 at p < 0.01 significance level.

Conclusions

The BMI and triglycerides levels were found to be significantly elevated for the EL group, pointing to an increased risk of EL occurrence in progressively more obese US population. The data also revealed a strong correlation between the number of subsequent epidural steroid injections and EL occurrence calling for caution with the use of corticosteroids.

The effects of light at night on circadian clocks and metabolism

Most organisms display endogenously produced ∼ 24-hour fluctuations in physiology and behavior, termed circadian rhythms. Circadian rhythms are driven by a transcriptional-translational feedback loop that is hierarchically expressed throughout the brain and body, with the suprachiasmatic nucleus of the hypothalamus serving as the master circadian oscillator at the top of the hierarchy. Appropriate circadian regulation is important for many homeostatic functions including energy regulation. Multiple genes involved in nutrient metabolism display rhythmic oscillations, and metabolically related hormones such as glucagon, insulin, ghrelin, leptin, and corticosterone are released in a circadian fashion. Mice harboring mutations in circadian clock genes alter feeding behavior, endocrine signaling, and dietary fat absorption. Moreover, misalignment between behavioral and molecular circadian clocks can result in obesity in both rodents and humans. Importantly, circadian rhythms are most potently synchronized to the external environment by light information and exposure to light at night potentially disrupts circadian system function. Since the advent of electric lights around the turn of the 20th century, exposure to artificial and irregular light schedules has become commonplace. The increase in exposure to light at night parallels the global increase in the prevalence of obesity and metabolic disorders. In this review, we propose that exposure to light at night alters metabolic function through disruption of the circadian system. We first provide an introduction to the circadian system, with a specific emphasis on the effects of light on circadian rhythms. Next we address interactions between the circadian system and metabolism. Finally, we review current experimental and epidemiological work directly associating exposure to light at night and metabolism.

Problematic intake of high-sugar/low-fat and high glycemic index foods by bariatric patients is associated with development of post-surgical new onset substance use disorders

Bariatric or weight loss surgery (WLS) patients are overrepresented in substance abuse treatment, constituting about 3% of admissions; about 2/3 of such patients deny problematic substance use prior to WLS. It is important to advance our understanding of the emergence of substance use disorders (SUDs) - particularly the New Onset variant - after WLS. Burgeoning research with both animal models and humans suggests that "food addiction" may play a role in certain forms of obesity, with particular risk conferred by foods high in sugar but low in fat. Therefore, we hypothesized that WLS patients who reported pre-WLS problems with High-Sugar/Low-Fat foods and those high on the glycemic index (GI) would be those most likely to evidence New Onset SUDs after surgery. Secondary data analyses were conducted using a de-identified database from 154 bariatric surgery patients (88% female, Mage=48.7 yrs, SD=10.8, Mtime since surgery=2.7 yrs, SD=2.2 yrs). Participants who endorsed pre-surgical problems with High-Sugar/Low-Fat foods and High GI foods were at greater risk for New Onset SUD in the post-surgical period. These findings remained significant after controlling for other predictors of post-surgical SUD. Our findings provide evidence for the possibility of addiction transfer among certain bariatric patients.

The impact of obesity on complications of elbow, forearm, and hand surgeries

PURPOSE

To compare the rates of postoperative complications in obese and nonobese patients following elbow, forearm, and hand surgeries.

METHODS

This case-control study examined 436 patients whose body mass index (BMI) was over 35 and who underwent hand, wrist, forearm, or elbow surgery between 2009 and 2013. Controls were patients (n = 433) with a BMI less than 30 who had similar surgeries over the same period, and who were frequency-matched by type of surgery (ie, bony, soft tissue, or nerve), age, and sex. Postoperative complications were defined as infection requiring antibiotic or reoperation, delayed incision healing, nerve dysfunction, wound dehiscence, hematoma, and other reoperation. Medical comorbidities (e.g., hypertension, diabetes, stroke, vascular disease, kidney disease, and liver disease) were recorded. Chi-square analyses were performed to explore the association between obesity and postoperative complications. Similar analyses were performed stratified by surgery type and BMI classification. Logisticregression modeling was performed to identify predictors of postoperative complications accounting for surgery type, BMI, the presence of comorbidities, patient age, and patient sex. This same model was also run separately for case and control patients.

RESULTS

The overall complication rate was 8.7% with similar rates between obese and nonobese patients (8.5% vs. 9.0%). Bony procedures resulted in the greatest risk of complication in both groups (15% each group). Multivariate analysis confirmed surgery type as the only significant predictor of complications for nonobese patients. However, among obese patients, both bony surgery and increasing BMI were associated with greater complication rates.

CONCLUSIONS

Not all obese patients appear to be at any higher risk for complications after elbow, forearm, and hand surgery compared with nonobese patients. However, there appears to be a dose-dependent effect of BMI among obese patients such that increasing obesity heightens the risk of complications, especially for those with a BMI greater than 45.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

A screening tool to assess and manage behavioral risk in the postoperative bariatric surgery patient: The WATCH

Bariatric surgery is increasingly recognized as a highly effective treatment for individuals who are severely obese. Amount of weight loss and resolution of comorbidities surpass those of nonsurgical approaches; however, suboptimal weight loss and weight regain are not uncommon. These outcomes, though not fully understood, are likely at least partially explained by failure to make long-term behavioral and/or cognitive changes. We are unaware of any established clinical tools to guide providers in assessing postoperative behaviors and identifying those who may require specialized treatment. The goal of this paper is to introduce a brief screening tool, The WATCH, to help clinicians assess and identify patients who may be at risk for poor or untoward outcomes post bariatric surgery. We first review the literature on postoperative outcomes, including weight loss, resolution of comorbidities, suboptimal outcomes, and development of problematic eating behaviors. We then provide an easily-recalled, five-item tool that assesses outcomes, and discuss patient responses that may necessitate further intervention or referral.

Effects of sleeve gastrectomy on lipid metabolism in an obese diabetic rat model

BACKGROUND

Laparoscopic sleeve gastrectomy (SG) is a popular bariatric procedure for treating morbid obesity. This study aimed to investigate the relation between SG and lipid metabolism in an obese diabetic rat model.

METHODS

Forty-five male Zucker diabetic fatty (ZDF) rats were divided into three groups: sham-operated (SO) control, gastric banding (GB), and SG. Six weeks after surgery, metabolic parameters, including plasma adiponectin level, small bowel transit, mRNA expression of peroxisome proliferator-activated receptor (PPAR)-α and PPARγ in the liver, skeletal muscle and white adipose tissue, and that of adiponectin in white adipose tissue, and triglyceride (TG) contents in the liver and skeletal muscle were measured.

RESULTS

Metabolic parameters in the GB and SG groups were significantly improved compared with those in the SO group. However, plasma total cholesterol (TC) and free fatty acid (FFA) concentrations were significantly lower while the plasma adiponectin level was significantly higher in the SG group than in the GB and SO groups. In addition, small bowel transit time was significantly shorter in the SG group than in the other two groups. Furthermore, in the SG group, mRNA expression of PPARα in the liver and skeletal muscle and that of adiponection and PPARγ in white adipose tissue were significantly higher, while TG in the liver and skeletal muscle were significantly lower, compared with those in the other two groups.

CONCLUSIONS

These results suggest that SG improves lipid metabolism compared with GB, although there were no significant differences in the effect on weight loss between the two procedures.

Super obesity in pregnancy: difficulties in clinical management

As the obesity pandemic continues in the United States, obesity in pregnancy has become an area of interest. Many studies focus on women with body mass index (BMI) ⩾ 30 kg m(-2). Unfortunately, the prevalence of patients with BMI ⩾ 50 kg m(-2) is rapidly increasing, and there are few studies specifically looking at pregnant women in this extreme category. The purpose of this article is to highlight some of the challenges faced and review the literature available to help guide obstetricians who might encounter such patients.

Duodenal switch versus Roux-en-Y gastric bypass for morbid obesity: systematic review and meta-analysis of weight results, diabetes resolution and early complications in single-centre comparisons

Long-term weight loss after Roux-en-Y gastric bypass (RYGB) in super-obese patients has not been ideal. Biliopancreatic diversion with duodenal switch (DS) is argued to be better; however, additional side effects are feared. The aim of the present study was to determine differences in results after DS and RYGB in publications from single-centre comparisons. A systematic review of studies containing DS and RYGB performed at the same centre was performed. Outcome data were weight results, resolution of comorbid conditions, perioperative results and complications. Main outcome was difference in weight loss after DS and RYGB. Secondary outcomes were difference in resolution of comorbidities, perioperative results and complications. The final analysis included 16 studies with in total 874 DS and 1,149 RYGB operations. When comparing weight results at the longest follow-up of each study, DS yielded 6.2 (95% confidence interval 5.0-7.5) body mass index units additional weight loss compared with RYGB, P < 0.001. Operative time and length of stay were significantly longer after DS, as well as the risk for post-operative leaks, P < 0.05. DS is more effective than RYGB as a weight-reducing procedure. However, this comes at the price of more early complications and might also yield slightly higher perioperative mortality.

Kidney function decline in metformin versus sulfonylurea initiators: assessment of time-dependent contribution of weight, blood pressure, and glycemic control

BACKGROUND AND OBJECTIVE

We recently reported that kidney function declined faster among initiators of sulfonylureas compared to metformin; however, sulfonylurea use compared to metformin use was also associated with increases in body mass index (BMI) and systolic blood pressure (SBP). We sought to determine if differences between sulfonylureas and metformin on kidney function decline were mediated by differential effects on BMI, SBP, or glucose control.

METHODS

We identified 13,238 veterans who initiated sulfonylurea or metformin treatment (2000–2007) with a baseline estimated glomerular filtration rate (eGFR) >60 mL/minute, and followed them until a study event occurred, non-persistence on treatment, loss of follow-up, or end of the study. The composite outcome was a sustained decline from baseline eGFR of ≥25%, end-stage renal disease, or death. We estimated the association of cumulative measurements of potential mediators including BMI, SBP, and glycated hemoglobin on the study outcome. We determined if controlling for these time-varying covariates accounted for the differences in outcome between sulfonylurea and metformin initiators.

RESULTS

Compared to sulfonylurea use, metformin use was associated with a lower risk for renal function decline or death [adjusted hazard ratio (aHR) 0.82, 95% confidence interval 0.70, 0.97]. This protective association remained significant [aHR 0.83 (0.70–0.98)] when accounting for the cumulative time-varying measurements of the three mediators of interest.

CONCLUSION

Metformin initiation was associated with a lower risk of kidney function decline or death compared to sulfonylureas, which which appeared to be independent of changes in BMI, SBP, and glycated hemoglobin over time.

A break in the obesity epidemic? Explained by biases or misinterpretation of the data?

Recent epidemiologic papers are presenting prevalence data suggesting breaks and decreases in obesity rates. However, before concluding that the obesity epidemic is not increasing anymore, the validity of the presented data should be discussed more thoroughly. We had a closer look into the literature presented in recent reviews to address the major potential biases and distortions, and to develop insights about how to interpret the presented suggestions for a potential break in the obesity epidemic. Decreasing participation rates, the use of reported rather than measured data and small sample sizes, or lack of representativeness, did not seem to explain presented breaks in the obesity epidemic. Further, available evidence does not suggest that stabilization of obesity rates is seen in higher socioeconomic groups only, or that urbanization could explain a potential break in the obesity epidemic. However, follow-ups of short duration may, in part, explain the apparent break or decrease in the obesity epidemic. On the other hand, a single focus on body mass index (BMI) ⩾25 or ⩾30 kg m(-)(2) is likely to mask a real increase in the obesity epidemic. And, in both children and adults, trends in waist circumferences were generally suggesting an increase, and were stronger than those reported for trends in BMI. Studies concluding that there is a recent break in the obesity epidemic need to be interpreted with caution. Reported studies presenting a break were mostly of short duration. Further, focusing on trends in waist circumference rather than BMI leads to a less optimistic conclusion: the public health problem of obesity is still increasing.

Is responsiveness to weight loss diets affected by family history of diabetes?

BACKGROUND

Obesity is associated with many metabolic and chronic diseases, such as diabetes and cardiovascular disease. Family history of diabetes (FHD) is also an important risk factor for type 2 diabetes. Furthermore, the presence of FHD and obesity has a synergic effect on risk of diabetes incidence. The aim of this study was to determine whether FHD influence the weight loss induced by weight loss diet.

METHODS

This study was an intervention between individuals with or without FHD. Seventy-eight positive FHD and 74 negative FHD individuals were participated in this study. Two groups were matched for age, gender, and body mass index (BMI). In the present study, expert interviewers collected socio-demographic data and prescribed dietary recommendations in a face-to-face method.

RESULTS

Dietary intervention significantly reduces the body weight and BMI in both groups, but these reductions were not different between negative and positive FHD groups. This study could not find any significant association between FHD and responsiveness to weight loss diets (β = -0.058; 95% confidence interval, -1.618 to 0.832; P = 0.526).

CONCLUSION

Individuals with FHD have higher risk for obesity and chronic diseases, but in the current study there was no difference in responsiveness to weight loss in individuals with a positive family history and those without a family history.

Obesity and the risk of stillbirth: a population-based cohort study

OBJECTIVE

Obesity is a known risk factor for stillbirth. However, this relationship has not been characterized fully. We attempted to further examine this relationship with a focus on delivery near and at term.

STUDY DESIGN

We designed a retrospective cohort study of singleton nonanomalous live births and stillbirths in the states of Washington and Texas to examine the associations of maternal prepregnancy body mass index (BMI) and risk of stillbirth. Confounder-adjusted hazard ratio of stillbirth in relation to BMI was estimated through Cox proportional hazards regression model. The hazard ratio was used to estimate the population-attributable risk. We also estimated the fetuses who were at risk for stillbirth based on gestational age.

RESULTS

Among 2,868,482 singleton births, the overall stillbirth risk was 3.1 per 1000 births (n = 9030). Compared with normal-weight women, the hazard ratio for stillbirth was 1.36 for overweight women, 1.71 for class I obese women, 2.00 for class II obese women, 2.48 for class III obese women, and 3.16 for women with a BMI of ≥50 kg/m(2). The fetuses who are at risk for stillbirth increased after 39 weeks' gestation for each obesity class; however, the risk increased more rapidly with increasing BMI. Women with a BMI of ≥50 kg/m(2) were at 5.7 times greater risk than normal weight women at 39 weeks' gestation and 13.6 times greater at 41 weeks' gestation. Obesity was associated with nearly 25% of stillbirth that occurred between 37 and 42 weeks' gestation.

CONCLUSION

There is a pronounced increase in the risk of stillbirth with increasing BMI; the association is strongest at early- and late-term gestation periods. Extreme maternal obesity is a significant risk factor for stillbirth.

Observational study of the effect of obesity on lung volumes

BACKGROUND

Severe obesity causes respiratory morbidity and mortality. The impact of obesity on the mechanics of breathing is not fully understood.

PATIENTS AND METHODS

We undertook a comprehensive observational study of lung volumes and elasticity in nine obese and nine normal weight subjects, seated and supine, during spontaneous breathing. Seated and supine total lung capacity (TLC) and subdivisions were measured by multibreath helium dilution method. Using balloon catheters, oesophageal (Poes) and gastric (Pgas) pressures were recorded. Transpulmonary pressure (PL) was calculated as mouth pressure (Pmouth)-Poes, and complete expiratory PL volume curves were measured.

RESULTS

The obese group had a body mass index (BMI) of 46.8 (17.2) kg/m(2), and the normal group had a BMI of 23.2 (1.6) kg/m(2) (p=0.001). Obese and normals were matched for age (p=0.233), gender (p=0.637) and height (p=0.094). The obese were more restricted than the normals (TLC 88.6 (16.9) vs 104.4 (12.3) %predicted, p=0.033; FEV1/FVC 79.6 (7.3) vs 82.5 (4.2) %, p=0.325), had dramatically reduced expiratory reserve volume (ERV 0.4 (0.4) vs 1.7 (0.6) L, p<0.001) and end-tidal functional residual capacity (FRC) was smaller (37.5 (6.9) vs 46.9 (4.6) %TLC, p=0.004) when seated, but was similar when supine (39.4 (7.7) vs 41.5 (4.3) %TLC, p=0.477). Gastric pressures at FRC were significantly elevated in the obese (seated 19.1 (4.7) vs 12.1 (6.2) cm H2O, p=0.015; supine 14.3 (5.7) vs 7.1 (2.6) cm H2O, p=0.003), as were end-expiratory oesophageal pressures at FRC (seated 5.2 (6.9) vs -2.0 (3.5) cm H2O, p=0.013; supine 14.0 (8.0) vs 5.4 (3.1) cm H2O, p=0.008). BMI correlated with end-expiratory gastric (seated R(2)=0.43, supine R(2)=0.66, p<0.01) and oesophageal pressures (seated R(2)=0.51, supine R(2)=0.62, p<0.01).

CONCLUSIONS

Obese subjects have markedly increased gastric and oesophageal pressures, both when upright and supine, causing dramatically reduced FRC and ERV, which increases work of breathing.

The body composition and excretory burden of lean, obese, and severely obese individuals has implications for the assessment of chronic kidney disease

Obesity could affect associations between creatinine generation, estimated body surface area, and excretory burden, with effects on chronic kidney disease assessment. We therefore examined the impact of obesity on the performances of estimated glomerular filtration rate (eGFR), the urine albumin:creatinine ratio (ACR), and excretory burden in 3611 participants of the Chronic Renal Insufficiency Cohort. Urine creatinine excretion significantly increased with body mass index (BMI) (34 and 31% greater at 40 kg/m(2) or more versus the normal of 18.5-25 kg/m(2)) in men and women, respectively, such that patients with a normal BMI and an ACR of 30 mg/g had the same 24-h albuminuria as severely obese patients with ACR 23 mg/g. The bias of eGFR (referenced to body surface area-indexed iothalamate (i-)GFR) had a U-shaped relationship to obesity in men but progressively increased in women. Nevertheless, obesity-associated body surface area increases were accompanied by a greater absolute (non-indexed) iGFR for a given eGFR, particularly in men. Two men with eGFRs of 45 ml/min per 1.73 m(2), height 1.76 m, and BMI 22 or 45 kg/m(2) had absolute iGFRs of 46 and 62 ml/min, respectively. The excretory burden, assessed as urine urea nitrogen and estimated dietary phosphorus, sodium, and potassium intakes, also increased in obesity. However, obese men had lower odds of anemia, hyperkalemia, and hyperphosphatemia. Thus, for a given ACR and eGFR, obese individuals have greater albuminuria, absolute GFR, and excretory burden. This has implications for chronic kidney disease management, screening, and research.

Stability of relative weight category and cardiometabolic risk factors among moderately and severely obese middle school youth

OBJECTIVE

To examine the stability of severe pediatric obesity relative to moderate obesity and associated changes in cardiometabolic risk from the beginning of 6th to the end of 8th grade.

METHODS

Participants in HEALTHY, a multi-site, cluster randomized school-based study designed to mitigate risk for type 2 diabetes, completed standardized assessments of height, weight, glucose, insulin, lipids, and blood pressure at the beginning of 6th grade and the end of 8th grade. Youth were classified as moderately obese (100-119% of the 95th percentile of BMI for age and gender) or severely obese (≥120% of the 95th percentile of BMI for age and gender). Generalized linear mixed models (GLMM) that controlled for relevant covariables were used to examine the relation between baseline demographic and cardiometabolic risk factors and BMI status, as well as changes in relative weight category and risk factors during middle school.

RESULTS

Severe obesity was more likely to endure over the course of middle school than was moderate obesity, and was associated with significantly higher levels of cardiometabolic risk.

CONCLUSIONS

Research with a specific focus on understanding, preventing, and treating severe obesity in children is warranted.

Pericardial fat, insulin resistance, and left ventricular structure and function in morbid obesity

BACKGROUND AND AIM

Morbid obesity is often accompanied by insulin resistance and increased ectopic fat surrounding the heart. We evaluated the relation of epicardial and pericardial fat with insulin resistance and left ventricular (LV) structure and function.

METHODS AND RESULTS

Epicardial and pericardial fat thicknesses were determined at 2-dimensional echocardiography in 80 morbid obese subjects [age 42 ± 12 years, 31% men, body mass index (BMI) 44.4 ± 7 kg/m(2)]. LV hypertrophy (LV mass ≥51 g/m(2.7)), inappropriately high LV mass for a given cardiac workload (observed vs predicted LV mass >128%), and stress-adjusted LV mid-wall fractional shortening were determined. Pericardial and epicardial fat thicknesses had direct associations with BMI (r = 0.40 and 0.45, both p < 0.01) and waist circumference (r = 0.37 and 0.45, both p < 0.01). Pericardial (partial r = 0.35, p < 0.01), but not epicardial fat thickness (partial r = 0.05, p = n.s.), was correlated with homeostasis model assessment-insulin resistance after adjustment for BMI. Pericardial fat also had a strong negative correlation with mid-wall fractional shortening (p = 0.01) and a positive one with inappropriately high LV mass (p < 0.01), while no such relation was found for epicardial fat (both p = n.s.). Independently of age, male sex, BMI, and anti-hypertensive treatment, pericardial fat thickness had an independent positive association with inappropriately high LV mass (β = 0.29, p = 0.02), and a negative one with stress-adjusted mid-wall fractional shortening (β = -0.26, p = 0.04).

CONCLUSIONS

Pericardial fat thickness is associated with insulin resistance, inappropriately high LV mass, and LV systolic dysfunction in obese individuals. Findings from this study confirm the existence of a connection between insulin resistance, cardiac ectopic fat deposition and cardiac dysfunction in morbid obesity.

Low intraoperative tidal volume ventilation with minimal PEEP is associated with increased mortality

Background

Anaesthetists have traditionally ventilated patients’ lungs with tidal volumes (TVs) between 10 and 15 ml kg⁻¹ of ideal body weight (IBW), without the use of PEEP. Over the past decade, influenced by the results of the Acute Respiratory Distress Syndrome Network trial, many anaesthetists have begun using lower TVs during surgery. It is unclear whether the benefits of low TV ventilation can be extended into the perioperative period.

Methods

We reviewed the records of 29 343 patients who underwent general anaesthesia with mechanical ventilation between January 1, 2008 and December 31, 2011. We calculated TV kg⁻¹ IBW, PEEP, peak inspiratory pressure (PIP), and dynamic compliance. Cox regression analysis with propensity score matching was performed to examine the association between TV and 30-day mortality.

Results

Median TV was 8.6 [7.7–9.6] ml kg⁻¹ IBW with minimal PEEP [4.0 (2.2–5.0) cm H₂O]. A significant reduction in TV occurred over the study period, from 9 ml kg⁻¹ IBW in 2008 to 8.3 ml kg⁻¹ IBW in 2011 (P=0.01). Low TV 6–8 ml kg⁻¹ IBW was associated with a significant increase in 30-day mortality vs TV 8–10 ml kg⁻¹ IBW: hazard ratio (HR) 1.6 [95% confidence interval (CI) [1.25–2.08], P=0.0002]. The association remained significant after matching: HR 1.63 [95% CI (1.22–2.18), P<0.001]. There was only a weak correlation between TV kg⁻¹ IBW and dynamic compliance (r=−0.006, P=0.31) and a weak-to-moderate correlation between TV kg⁻¹ IBW and PIP (r=0.32 P<0.0001).

Conclusions

Use of low intraoperative TV with minimal PEEP is associated with an increased risk of 30-day mortality.

Childhood abuse, adult interpersonal abuse, and depression in individuals with extreme obesity

This study sought to examine (a) a mediational model of childhood abuse, adult interpersonal abuse, and depressive symptoms and (b) the impact of weight-related teasing on rates and correlates of childhood abuse. Charts of 187 extremely obese individuals seeking psychological clearance for bariatric (weight-loss) surgery were retrospectively examined. Among the participants, 61% reported a history of childhood abuse, 30.5% reported adult interpersonal abuse, and 15% reported clinically significant depressive symptoms. Initially, the relationship between childhood abuse and current depressive symptoms was significant (p<.001). However, the introduction of adult interpersonal abuse as a mediator in the model reduced the magnitude of its significance (Sobel's test p=.01). The associations between childhood abuse and adult interpersonal abuse and between adult interpersonal abuse and depressive symptoms were significant (p<.001 and p=.002, respectively), and the model showed a good fit across multiple indices. Finally, weight-related teasing was a significant moderator in the relationship between childhood and adult interpersonal abuse. Bariatric surgery patients report elevated rates of childhood abuse that are comparable to rates in psychiatric populations (e.g., eating disorders, depression), and higher than those in community samples and other medical populations. The relationship between child abuse and depressive symptomatology may be partially explained by the presence of adult interpersonal abuse; additionally, the relationship between childhood and adult interpersonal abuse was stronger for those who did not endure weight-related teasing than for those who did.

Severe obesity, heart disease, and death among white, African American, and Hispanic postmenopausal women

OBJECTIVE

To compare mortality, nonfatal coronary heart disease (CHD), and congestive heart failure (CHF) risk across BMI categories in white, African American, and Hispanic women, with a focus on severe obesity (BMI ≥ 40), and examine heterogeneity in weight-related CHD risk.

METHODS

Among 156,775 Women's Health Initiative observational study and clinical trial participants (September 1993-12 September 2005), multivariable Cox models estimated relative risk for mortality, CHD, and CHF. CHD incidence was calculated by anthropometry, race, and cardiovascular risk factors (CVRF).

RESULTS

Mortality, nonfatal CHD, and CHF incidence generally rose with BMI category. For severe obesity versus normal BMI, hazard ratios (HRs, 95% confidence interval) for mortality were 1.97 (1.77-2.20) in white, 1.55 (1.20-2.00) in African American, and 2.59 (1.55-4.31) in Hispanic women; for CHD, HRs were 2.05 (1.80-2.35), 2.24 (1.57-3.19), and 2.95 (1.60-5.41) respectively; for CHF, HRs were 5.01 (4.33-5.80), 3.60 (2.30-5.62), and 6.05 (2.49-14.69). CVRF variation resulted in substantial variation in CHD rates across BMI categories, even in severe obesity. CHD incidence was similar by race/ethnicity when differences in BMI or CVRF were accounted for.

CONCLUSIONS

Severe obesity increases mortality, nonfatal CHD, and CHF risk in women of diverse race/ethnicity. CVRF heterogeneity contributes to variation in CHD incidence even in severe obesity.

Obesity and cardiovascular diseases: implications regarding fitness, fatness, and severity in the obesity paradox

Obesity has been increasing in epidemic proportions, with a disproportionately higher increase in morbid or class III obesity, and obesity adversely affects cardiovascular (CV) hemodynamics, structure, and function, as well as increases the prevalence of most CV diseases. Progressive declines in physical activity over 5 decades have occurred and have primarily caused the obesity epidemic. Despite the potential adverse impact of overweight and obesity, recent epidemiological data have demonstrated an association of mild obesity and, particularly, overweight on improved survival. We review in detail the obesity paradox in CV diseases where overweight and at least mildly obese patients with most CV diseases seem to have a better prognosis than do their leaner counterparts. The implications of cardiorespiratory fitness with prognosis are discussed, along with the joint impact of fitness and adiposity on the obesity paradox. Finally, in light of the obesity paradox, the potential value of purposeful weight loss and increased physical activity to affect levels of fitness is reviewed.

Body mass index and mortality in patients on maintenance hemodialysis: a meta-analysis

PURPOSE

In patients undergoing maintenance hemodialysis (MHD), increasing numbers of studies have reported a reduced mortality in patients with an increased body mass index (BMI). This article provides a meta-analysis on the assessment of the relationship between BMI and mortality in MHD patients.

METHODS

A systemic literature review was conducted to identify studies that examined all-cause mortality, with or without cardiovascular events, on the basis of bodyweight or obesity measures in MHD population published before October 2012.

RESULTS

Eight observational studies with a total of 190,163 patients were included. Compared to the individuals with a normal BMI, overweight patients and obese patients were associated with lower all-cause mortality [relative risk (RR) 0.86, 95% confidence interval (CI) 0.84-0.88; RR 0.77, 95% CI 0.75-0.78, respectively] and cardiovascular mortality (RR 0.86; 95% CI 0.81-0.91; RR 0.78, 95% CI 0.73-0.83, respectively). Underweight patients had relatively higher all-cause and cardiovascular mortality (RR 1.22, 95% CI 1.20-1.25; RR 1.19, 95% CI 1.11-1.28, respectively). In an obesity-stratified analysis, the patients with moderate or severe obesity presented a strongly decreased all-cause mortality risk (RR 0.64, 95% CI 0.61-0.68) and cardiovascular mortality risk (RR 0.63, 95% CI 0.53-0.75) compared to patients with mild obesity (RR 0.74, 95% CI 0.71-0.77; RR 0.81, 95% CI 0.75-0.87, respectively).

CONCLUSIONS

These findings show that overweight and obese patients have lower all-cause and cardiovascular mortality rates in patients undergoing MHD. Body weight management and optimized nutritional and metabolic support should help to reduce the high mortality rates that are prevalent in the hemodialysis population.

The bariatric physician

Obesity is a rapidly increasing problem that has wide implications for the National Health Service. At present, obesity is not being addressed in a joined-up and standardised manner. This has downstream effects for the health service, the economy and society as a whole. As highlighted by a recent RCP report, there is a need for a new class of dedicated specialists who can evaluate individuals with health problems that are related to obesity, direct their care in a coordinated fashion, act as an advocate for their needs and be able to liaise with multiple different services to improve the provision of patient care. In this article, we discuss the role of this specialist - the bariatric physician.

Severe obesity and diabetes self-care attitudes, behaviours and burden: implications for weight management from a matched case-controlled study. Results from Diabetes MILES--Australia

AIMS

To investigate whether diabetes self-care attitudes, behaviours and perceived burden, particularly related to weight management, diet and physical activity, differ between adults with Type 2 diabetes who are severely obese and matched non-severely obese control subjects.

METHODS

The 1795 respondents to the Diabetes MILES--Australia national survey had Type 2 diabetes and reported height and weight data, enabling BMI calculation: 530 (30%) were severely obese (BMI ≥ 35 kg/m(2); median BMI = 41.6 kg/m(2)) and these were matched with 530 control subjects (BMI < 35 kg/m(2); median BMI = 28.2 kg/m(2)). Diabetes self-care behaviours, attitudes and burden were measured with the Diabetes Self-Care Inventory-Revised. Within-group and between-group trends were examined.

RESULTS

The group with BMI ≥ 35 kg/m(2) was less likely to achieve healthy diet and exercise targets, placed less importance on diet and exercise recommendations, and found the burden of diet and exercise recommendations to be greater than the group with BMI < 35 kg/m(2). The group with BMI ≥ 35 kg/m(2) was more likely to be actively trying to lose weight, but found weight control a greater burden. These issues accentuated with increasing obesity and were greatest in those with BMI > 45 kg/m(2). There were no between-group differences in other aspects of diabetes self-care: self-monitoring of blood glucose, use of medications and smoking. Moderate-to-severe symptoms of depression were independently associated with reduced likelihood of healthy diet and physical activity, and with greater burden associated with diet, physical activity and weight management.

CONCLUSIONS

Severely obese people with diabetes demonstrated self-care attitudes, behaviours and burdens that infer barriers to weight loss. However, other important diabetes self-care behaviours are supported equally by severely obese and non-severely obese individuals.

Effect of physical activity on weight loss, energy expenditure, and energy intake during diet induced weight loss

OBJECTIVE

Objective measurements of physical activity (PA), energy expenditure (EE) and energy intake can provide valuable information regarding appropriate strategies for successful sustained weight loss.

DESIGN AND METHODS

The total EE was examined by doubly labeled water, resting metabolic rate by indirect calorimetry, PA with activity monitors, and energy intake by the intake/balance technique in 116 severely obese undergoing intervention with diet alone (DO) or diet plus PA (D-PA).

RESULTS

Weight loss of 9.6 ± 6.8 kg resulted in decreased EE which was not minimized in the D-PA group. Comparing the highest and lowest quartiles of increase in PA revealed a lower decrease in TDEE (-122 ± 319 vs. -376 ± 305 kcal day⁻¹), elimination of the drop in AEE (83 ± 279 vs. -211 ± 284 kcal day⁻¹) and greater weight loss (13.0 ± 7.0 vs. 8.1 ± 6.3 kg). Increased PA was associated with greater adherence to energy restriction and maintenance of greater weight loss during months 7-12.

CONCLUSION

Noncompliance to prescribed PA in the DO and D-PA groups partially masked the effects of PA to increase weight loss and to minimize the reduced EE. Increased PA was also associated with improved adherence to prescribed caloric restriction. A strong recommendation needs to be made to improve interventions that promote PA within the context of behavioral weight loss interventions.

Obstructive Sleep Apnea and Surgery: Quality Improvement Imperatives and Opportunities

Obstructive sleep apnea (OSA) is more common in surgical candidates than in the general population and may increase susceptibility to perioperative complications that range from transient desaturation to catastrophic injuries. Understanding the potential impact of OSA on patients' surgical risk profile is of particular interest to otolaryngologists, who routinely perform airway procedures-including surgical procedures for treatment of OSA. Whereas the effects of OSA on long-term health outcomes are well documented, the relationship between OSA and surgical risk is not collinear, and clear consensus on the nature of the association is lacking. Better guidelines for optimization of pain control, perioperative monitoring, and surgical decision making are potential areas for quality improvement efforts. Many interventions have been suggested to mitigate the risk of adverse events in surgical patients with OSA, but wide variations in clinical practice remain. We review the current literature, emphasizing recent progress in understanding the complex pathophysiologic interactions noted in OSA patients undergoing surgery and outlining potential strategies to decrease perioperative risks.

Association of immune and metabolic receptors C5aR and C5L2 with adiposity in women

Adipose tissue receptors C5aR and C5L2 and their heterodimerization/functionality and interaction with ligands C5a and acylation stimulating protein (ASP) have been evaluated in cell and rodent studies. Their contribution to obesity factors in humans remains unclear. We hypothesized that C5a receptors, classically required for host defense, are also associated with adiposity. Anthropometry and fasting blood parameters were measured in 136 women divided by body mass index (BMI): normal/overweight (≤30 kg/m(2); n = 34), obese I (≤45 kg/m(2); n = 33), obese II (≤51 kg/m(2); n = 33), and obese III (≤80 kg/m(2); n = 36). Subcutaneous and omental adipose tissue C5aR and C5L2 expression were analysed. C5L2 expression was comparable between subcutaneous and omental across all BMI groups. Plasma ASP and ASP/omental C5L2 expression increased with BMI (P < 0.001 and P < 0.01, resp.). While plasma C5a was unchanged, C5aR expression decreased with increasing BMI in subcutaneous and omental tissues (P < 0.01 and P < 0.05, resp.), with subcutaneous omental depots. Omental C5L2/C5aR ratio increased with BMI (P < 0.01) with correlations between C5L2/C5aR and waist circumference, HDL-C, and adiponectin. Tissue and BMI differences in receptors and ligands, particularly in omental, suggest relationship to metabolic disturbances and highlight adipose-immune interactions.

The complex associations among sleep quality, anxiety-depression, and quality of life in patients with extreme obesity

INTRODUCTION

Sleep duration and quality have been associated with obesity. Sleep disturbance has been reported to be associated with stress and depression among non-obese populations, but these relationships have not been previously examined in the obese population. The objective of the current study was to examine the complex associations among sleep disturbance, quality of life, anxiety, and depression in a patient sample with severe obesity.

METHODS

Two hundred seventy consecutively recruited patients with a mean body mass index (BMI) of 47.0 kg/m² were studied. The correlation coefficient, multiple linear regressions, and structural equation modeling (SEM) analysis were used to evaluate the association between the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Impact of Weight on Quality of Life-Lite (IWQOL-Lite) and Hospital Anxiety and Depression Scale (HADS).

RESULTS

The mean (standard deviation; SD) PSQI score was 8.59 (5.11), and mean ESS score was 8.84 (5.79). After controlling for potential confounders, poor sleep quality and excessive daytime sleepiness were found to be significantly associated of all the components of IWQOL-Lite; physical function (β = -0.32, β = -0.27; P < 0.01), self-esteem (β = -0.23, β = -0.30; P < 0.05), sexual-life (β = -0.30, β = -0.35; P < 0.05), public distress (β = -0.39, β = -0.39; P < 0.01), and work (β = -0.26, β = -0.48; P < 0.01). We also found that the PSQI global score had a positive significant association with anxiety (β = 0.29; P = 0.01) and depression (β = 0.31; P = 0.01) components of HADS.

CONCLUSION

Poor sleep quality was strongly associated with mood disturbance and poor quality of life among extremely obese patients. Future interventions are needed to address sleep disturbance to prevent further development of psychological co-morbidity and potentially worsening of obesity among these individuals.

Does body mass index affect the outcome of unicompartmental knee replacement?

BACKGROUND

Obesity is considered to be a contraindication for unicompartmental knee replacement (UKR). The aim was to study the impact of BMI on failure rate and clinical outcome of the Oxford mobile bearing UKR.

METHOD

Two thousand four hundred and thirty-eight medial Oxford UKRs were studied prospectively and divided into groups: BMI<25 (n=378), BMI 25 to <30 (n=856), BMI 30 to <35 (n=712), BMI 35 to <40 (n=286), and BMI 40 to <45 (n=126) and BMI≥45 (n=80).

RESULTS

There was no significant difference in survival rate between groups. At a mean follow-up of 5years (range 1-12years) there was no significant difference in the Objective American Knee Society Score between groups. There was a significant (p<0.01) trend with the Oxford Knee Score (OKS) and Functional American Knee Society Scores decreasing with increasing BMI. As there was an opposite trend (p<0.01) in pre-operative OKS, the change in OKS increased with increasing BMI (p=0.048). The mean age at surgery was significantly (p<0.01) lower in patients with higher BMI.

CONCLUSIONS

Increasing BMI was not associated with an increasing failure rate. It was also not associated with a decreasing benefit from the operation. Therefore, a high BMI should not be considered a contra-indication to mobile bearing UKR.

LEVEL OF EVIDENCE

IV.

Rasch analysis of the General Self-Efficacy Scale in a sample of persons with morbid obesity

Background

Self-efficacy is needed for effectuating lifestyle changes, and it is therefore an important target related to health. The purpose of this study was to evaluate the psychometric properties of the General Self-Efficacy Scale (GSE) using Rasch analysis in a sample of adults with morbid obesity.

Methods

A convenience sample of adults with morbid obesity was recruited from patient education courses. A total of 141 participants completed the GSE and a demographic questionnaire at the beginning of the course. The statistical approach included analysis of rating scale function, item fit to the Rasch partial credit model, unidimensionality, aspects of person-response validity, person-separation reliability, and differential item function. A version omitting items with poor fit to the Rasch model was also evaluated.

Results

The rating scale did not advance monotonically for item #2 in the original 10-item version, and the first three GSE items did not demonstrate acceptable goodness-of-fit to the Rasch model. In a 7-item version omitting these three items, the rating scale functioned well for all items, and all items demonstrated good fit to the Rasch model. Both the 10-item and 7-item versions of the GSE partially met the criteria for unidimensionality. Neither version met the criterion for person response validity, although the results were slightly better for the 7-item than for the 10-item version. Both versions of the GSE demonstrated the ability to separate the respondents into three distinct levels of general self-efficacy. Several items had differential item function in relation to age, education or work status, but there were fewer in the 7-item version.

Conclusions

For adults with morbid obesity, a 7-item version of the GSE seems to have better psychometric properties than the original 10-item version.

Associations between physical activity and quality of life outcomes in adults with severe obesity: a cross-sectional study prior to the beginning of a lifestyle intervention

Background

Severely obese individuals who seek lifestyle interventions have impaired quality of life (QoL). Research suggests that physical activity (PA) plays a role in weight reduction and improved health in this group, but knowledge about the association of PA with QoL outcomes is sparse and inconsistent. The aim of this study was to investigate whether a higher level of PA was independently associated with higher QoL in severely obese individuals prior to the beginning of a lifestyle intervention.

Methods

During 2010, a total of 49 severely obese individuals who began a lifestyle intervention programme in Western Norway agreed to participate in the study. Data were collected prior to the beginning of the intervention. QoL was measured by a one-item scale on life satisfaction and the SF-36, PA was measured by an accelerometer, and clinical data were collected by health staff. Linear regression analyses were used to determine the associations between PA and QoL outcomes (life satisfaction, physical functioning, and mental health), adjusting for age, gender, and body mass index (BMI).

Results

In the adjusted analyses, we found positive relationships between PA and life satisfaction (Stand. coeff. 0.39, p = 0.024) and physical functioning (Stand. coeff. 0.34, p = 0.025). There was no association between PA and mental health (Stand. coeff. 0.15, p = 0.376).

Conclusion

This study detected associations between objectively measured PA and life satisfaction as well as physical functioning in a group of severely obese individuals before they began a lifestyle intervention programme.

The disproportionate economic burden associated with severe and complicated obesity: a systematic review

Burden of disease studies typically classify individuals with a body mass index (BMI) ≥ 30 kg m(-2) as a single group ('obese') and make comparisons to those with lower BMIs. Here, we review the literature on the additional economic burden associated with severe obesity or classes 3 and 4 obesity (BMI ≥ 40 kg m(-2) ), the fastest growing category of obesity, with the aim of exploring and disaggregating differences in resource use as BMI increases beyond 40 kg m(-2) . We recognize the importance of comparing classes 3 and 4 obesity to less severe obesity (classes 1 and 2) as well as quantifying the single sub-class impacts (classes 3 and 4). Although the latter analysis is the aim of this review, we include results, where found in the literature, for movement between the recognized subclasses and within classes 3 and 4 obesity. Articles presenting data on the economic burden associated with severe obesity were identified from a search of Ovid MEDLINE, EMBASE, EBSCO CINAHL and Cochrane Library databases. Data were extracted on the direct costs, productivity costs and resource use associated with severe obesity along with estimates of the multiplier effects associated with increasing BMI. Fifteen studies were identified, of which four disaggregated resource use for BMI ≥ 40 kg m(-2) . The multiplier effects derived for a variety of different types of costs incurred by the severely obese compared with those of normal weight (18.5 kg m(-2)  < BMI < 25 kg m(-2) ) ranged from 1.5 to 3.9 for direct costs, and from 1.7 to 8.0 for productivity costs. There are few published data on the economic burden of obesity disaggregated by BMI ≥ 40 kg m(-2) . By grouping people homogenously above a threshold of BMI 40 kg m(-2) , the multiplier effects for those at the highest end of the spectrum are likely to be underestimated. This will, in turn, impact on the estimates of cost-effectiveness for interventions and policies aimed at the severely obese.

Differential changes in exercise performance after massive weight loss induced by bariatric surgery

BACKGROUND

Exercise performance and pulmonary function are often impaired in severely obese subjects. Bariatric surgery represents the most effective therapy for severe obesity, but data on changes in exercise performance after massive weight loss induced by bariatric surgery have rarely been assessed so far.

METHODS

Exercise performance was obtained by bicycle spiroergometry in 18 severely obese patients before and at least 1 year after bariatric surgery. Additionally, pulmonary function was assessed by spirometry.

RESULTS

BMI was reduced from 46.3 ± 1.6 to 33.5 ± 1.4 kg/m(2) after surgery. Pulmonary function (forced expiratory volume within 1 s; inspiratory vital capacity) improved after weight loss (both p ≤ 0.01). At peak exercise, heart rate (HR) peak, absolute oxygen uptake (VO(2)) peak, and load peak did not differ between both assessments (all p > 0.25). However, relative (related to actual body weight) VO(2) peak and workload peak were higher after than before surgery (both p ≤ 0.005), while gross efficiency peak and ventilatory equivalent peak remained unchanged (both p > 0.30). At anaerobic threshold (AT), patients showed lower HR AT and absolute VO(2) AT after than before surgery (both p < 0.05), while absolute workload AT did not differ (p = 0.58). In turn, relative VO(2) AT did not change (p = 0.30), whereas relative workload AT was higher after surgery (p = 0.04). Also, ventilatory efficiency AT and gross efficiency AT tended to be improved (both p = 0.08). Before surgery, the patients performed 27.0 % of VO(2) peak above their AT, while this fraction increased to 35.3 % (p = 0.006).

CONCLUSIONS

Results indicated differential changes in exercise performance, with the relative but not the absolute peak performance being improved after massive weight loss. Interestingly, anaerobic exercise tolerance was markedly improved after surgery.

Use of a Shortened Endotracheal Tube as a Tracheostomy Tube in a Morbidly Obese Patient

The rising prevalence of morbidly obese patients presents unique challenges to the intensivist, including management of the airway. We present a case where commercially available tracheostomy tubes were of insufficient length due to the patient's body habitus, with potentially disastrous consequences. As a solution, an endotracheal tube was used as the tracheostomy tube to provide sufficient length for correct positioning and to enable weaning from mechanical ventilation. The adjustable flange from a tracheostomy kit was used to secure the tube in position. Our case illustrates one possible solution to the problem of tracheostomy tube positioning in morbidly obese patients.