Overweight and Obesity: Two Predictors for Worse Early Outcome in Total Hip Replacement?

Objective: Doctors and patients assume that overweight and obesity are negative predictors for good and excellent early outcome after total hip replacement. It was the purpose of this prospective investigation to assess whether overweight or obese patients have worse early postoperative outcome in comparison with normal‐weight patients. Research Methods and Procedures: Sixty‐seven consecutive patients receiving a total hip replacement were enrolled in the study. Patients were grouped into three samples according to BMI: normal‐weight (BMI < 25 kg/m², n = 11), overweight (BMI 25 to 29.9 kg/m², n = 36), and obese (BMI ≥30 kg/m², n = 20). At 10 days and at 3 months after surgery, the patient‐centered outcome was analyzed with a self‐administered assessment chart, the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Statistical analysis was performed with a multiple regression model that took into consideration further confounding parameters (age, sex, affected side, anchorage of the implant, duration of surgery, hospital length of stay, and prior pain, stiffness, and function). Results: No significant influence of individual BMI on subjective outcome according to the WOMAC questionnaire was observed at either 10 days or 3 months after surgery. Hospital length of stay was comparable, and WOMAC scores did not differ significantly preoperatively, at 10 days, or at 3 months postoperatively among patients with different BMI. Discussion: These data showed that the BMI of the patients in our study sample had no significant impact on early outcome or hospital length of stay after total hip replacement. Our data suggest, therefore, that body weight should not be a justification for withholding surgery from overweight or obese patients.     

Modeling the Impact of Adjustable Gastric Banding on Survival in Patients with Morbid Obesity

Objective: Morbid obesity is associated with premature death. Adjustable gastric banding may lead to substantial weight loss in patients with morbid obesity. Little is known about the impact of weight loss on survival after adjustable gastric banding. We therefore developed a mathematical model to estimate life expectancy in patients with a body mass index (BMI) ≥40 kg/m² undergoing bariatric surgery. Research Methods and Procedures: We developed a nonhomogeneous Markov chain consisting of five states: the absorbing state (“dead”) and the four recurrent states BMI ≥40 kg/m², BMI 36 to 39 kg/m², BMI 32 to 35 kg/m², and BMI 25 to 31 kg/m². Scenarios of weight loss and age‐ and sex‐dependent risk of death, as well as BMI‐dependent excess mortality were extracted from life tables and published literature. All patients entered the model through the state of BMI ≥40 kg/m². Results: In men aged either 18 or 65 years at the time of surgery, who moved from the state BMI ≥40 kg/m² to the next lower state of BMI 36 to 39 kg/m², life expectancy increased by 3 and 0.7 years, respectively. In women aged either 18 or 65 years at the time of surgery, who moved from the state BMI ≥40 kg/m² to the next lower state BMI 36 to 39 kg/m², life expectancy increased by 4.5 and 2.6 years, respectively. Weight loss to lower BMI strata resulted in further gains of life expectancy in both men and women. Discussion: Within the limitations of the modeling study, adjustable gastric banding in patients with morbid obesity may substantially increase life expectancy.     

Lipoprotein Oxidation and Plasma Vitamin E in Nondiabetic Normotensive Obese Patients

Objective: To correlate the susceptibility of low‐(LDL) and very‐low‐density lipoprotein to oxidation in vitro and the concentrations of serum antibodies against malondialdehyde‐modified LDL and plasma vitamin E with the anthropometric and laboratory characteristics of obesity. Research Methods and Procedures: A total of 75 nondiabetic, normotensive obese patients were assigned to one of four groups according to their body mass index (BMI): moderately obese (30 ≤ BMI ≤ 34.9 kg/m², n = 11), severely obese (35 ≤ BMI ≤ 39.9 kg/m², n = 20), morbidly obese (40 ≤ BMI ≤ 50 kg/m², n = 29), and very severely obese (BMI > 50 kg/m², n = 15). Results: The oxidation lag time for LDL from patients with a BMI ≥35 kg/m² was shorter than that for LDL from non‐obese controls (n = 13), whereas very‐low‐density lipoprotein oxidation lag times were not significantly different. The serum antibodies against modified LDL were similar in all groups, whereas the plasma vitamin E concentrations of obese patients were decreased (p ≤ 0.01). There was a negative correlation between LDL oxidation lag time and BMI (r = ?0.35, p = 0.0008), and between plasma vitamin E and BMI (r = ?0.53, p < 0.0001) and waist‐to‐hip ratio (r = ?0.40, p = 0.0003). Discussion: The LDL of nondiabetic, normotensive obese patients is more readily oxidized, and plasma vitamin E concentrations are low. These are both risk factors for coronary heart disease.     

BMI and Severity of Clinical and Radiographic Signs of Hip Osteoarthritis

Obesity might be involved in the pathogenesis of osteoarthritis (OA) not only via increased mechanical loading, but also via an inflammatory component possibly causing increased pain and functional disability. The study aim was to examine the relationship between BMI and clinical symptoms as well as radiographic severity of OA in patients scheduled for primary total hip arthroplasty (THA). We conducted a cross‐sectional study of 855 patients scheduled for a first THA for primary OA at a single centre between November 2001 and December 2006. The primary outcome was clinical and radiographic severity of OA, which was evaluated in four BMI categories (18.5–24.9, 25–29.9, 30–34.9 and ≥35 kg/m²). We used the Harris Hip Score (HHS) and the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) to assess pain and function. The severity of radiographic hip joint damage was evaluated using the Kellgren–Lawrence classification. Multivariate analyses were performed to adjust for potential confounders. In patients scheduled for THA, increasing BMI was associated with significantly higher levels of pain and functional disability on both HHS (P for trend <0.001) and WOMAC (P for trend <0.001). However, the degree of radiographic joint damage remained similar across BMI categories. These findings emphasize the need to further investigate the potential pathogenic role of obesity and low‐grade inflammation in OA and underscore the importance of obesity prevention to avoid early prosthetic replacement of the hip.     

Adapted Changes in Left Ventricular Structure and Function in Severe Uncomplicated Obesity

Objective: A massive amount of fat tissue, as that observed in obese subjects with BMI over 50 kg/m², could affect cardiac morphology and performance, but few data on this issue are available. We sought to evaluate cardiac structure and function in uncomplicated severely obese subjects. Research Methods and Procedures: We studied 55 uncomplicated severely obese patients, 40 women, 15 men, mean age 35.5 ± 10.2 years, BMI 51.2 ± 8.8 kg/m², range 43 to 81 kg/m², with a history of fat excess of at least 10 years, and 55 age‐matched normal‐weight subjects (40 women, 15 men, mean BMI 23.8 ± 1.2 kg/m²) as a control group. Each subject underwent an echocardiogram to evaluate left ventricular (LV) mass and geometry and systolic and diastolic function. Results: Severely obese subjects showed greater LV mass and indexed LV mass than normal‐weight subjects (p < 0.01 for all parameters). Nevertheless, LV mass was appropriate for sex, height^2.7, and stroke work in most (77%) uncomplicated severely obese subjects. In addition, no significant difference in LV mass indices and LV mass appropriateness between obese subjects with BMI ≥ 50 kg/m² and those with BMI ≤ 50 kg/m² was found. Obese subjects also showed higher ejection fraction and midwall shortening than normal‐weight subjects (p = 0.05 and p < 0.01, respectively), suggesting a hyperdynamic systolic function. No significant difference in systolic performance between obese subjects with BMI ≥ 50 kg/m² and those with BMI ≤ 50 kg/m² was seen. Discussion: Our data show that uncomplicated severe obesity, despite the massive fat tissue amount, is associated largely with adapted and appropriate changes in cardiac structure and function.     

Influence of Body Mass Index (BMI) on Functional Improvements at 3 Years Following Total Knee Replacement: A Retrospective Cohort Study

Background

The number of patients presenting for total knee replacement who are classified as obese is increasing. The functional benefits of performing TKR in these patients are unclear.

Aim

To assess the influence pre-operative body mass index has upon knee specific function, general health status and patient satisfaction at 3 years following total knee replacement.

Design

Retrospective comparative cohort study using prospectively collected data from an institutional arthroplasty register.

Methods

1367 patients were assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Trust Short Form-36 (SF-36) scores supplemented by a validated measure of satisfaction pre-operatively and subsequently at 1,2 and 3 year post-operatively. Comparisons were made by dividing the cohort into 4 groups based on body mass index (BMI) 18.5–25.0 kg/m² (n = 253);>25.0–30.0 kg/m² (n = 559);>30.0−35.0 kg/m² (n = 373);>35.0 kg/m² (n = 182).

Results

Despite lower pre-operative, 1 and 3 year WOMAC and SF-36 scores patients with the highest BMIs >35.0 kg/m² experienced similar improvements to patients with a ‘normal‘ BMI (18.5–25.0 kg/m²) at 1 year (Difference in WOMAC improvement = 0.0 (95%CI −5.2 to 5.2), p = 1.00) and this improvement was sustained at up to 3 years (Difference in 1 year to 3 year improvement = 2.2 (95%CI: −2.1 to 6.5), p = 1.00). This effect was also observed for the SF-36 mental and physical component scores. Despite equivalent functional improvements levels of satisfaction in the >35.0 kg/m² group were lower than for any other BMI group (>35.0 kg/m² = 84.6% satisfied versus 18.5–5.0 kg/m² = 93.3% satisfied,p = 0.01) as was the proportion of patients who stated they would have the operation again (>35.0 kg/m² = 69.6% versus 18.5–25.0 kg/m² = 82.2%,p = 0.01).

Conclusion

Obese and morbidly obese patients gain as much functional benefit from total knee replacement as patients with lesser body mass indexes. This benefit is maintained for up to 3 years following surgery. However, these patients are less satisfied with their knee replacement and almost a third would not have the operation again.     

Relationship between Obesity and Health-Related Quality of Life in Men

Objective: Few studies examining the relationship between obesity and health-related quality of life (HRQOL) have used a medical outpatient population or demonstrated a relationship in men. Furthermore, most studies have not adequately considered comorbid illness. The goal of this study was to examine the relationship between body mass index (BMI) and HRQOL in male outpatients while considering comorbid illness. Research Methods and Procedures: This cross-sectional study examined 1168 male outpatients from Durham Veterans’ Affairs Medical Center. Multiple linear regression was used to examine the relationship of BMI with each subscale from the Medical Outcomes Study Short Form 36 while adjusting for age, race, comorbid illness, depression, and physical activity. Results: Participants had a mean age of 54.7 ± 5.6 years; 69% were white and 29% were African American. The distribution for BMI was as follows: 18.5 to <25 kg/m² (21%), 25 to <30 kg/m² (43%), 30 to <35 kg/m² (25%), 35 to <40 kg/m² (8%), and ≥40 kg/m² (3%). Mean Short Form 36 subscale scores were lower than U.S. norms by an average of 27%. Individuals with BMI ≥40 kg/m² had significantly lower scores compared with normal weight individuals on the Role-Physical and Vitality subscales. On the Physical Functioning and Physical Component subscales, lower scores were observed at BMI ≥35 kg/m². On the Bodily Pain subscale, lower scores were observed at BMI ≥25 kg/m². Discussion: An inverse relationship between BMI and physical aspects of HRQOL exists in a population of male outpatients. Increased BMI was most prominently associated with bodily pain; this relationship should receive more attention in clinical care and research.     

Weight Loss Surgery Eligibility According to Various BMI Criteria Among Adolescents

A BMI cutoff point at the 99th percentile for age and gender or at 40 kg/m² has been suggested for more aggressive treatment of adolescent obesity. The main objective of this study was to determine the proportion of adolescents eligible for weight loss surgery (WLS) based on various BMI cutoff points. Data was extracted from the electronic medical record database of an urban pediatric ambulatory care center over 4 years. National data were used to calculate BMI percentiles (Centers for Disease Control and Prevention (CDC), 2000). Eligibility for WLS was based on a BMI percentile criterion (≥99th percentile) or the adult WLS cutoff point (≥40 kg/m²). The sample consisted of 3,220 adolescents aged 12–17.9 years, of which 53% were female, 55% were of black race, and 17% of Hispanic ethnicity. Overall, 88 (3%) adolescents had a BMI ≥40 kg/m² and 236 (7%) had a BMI ≥99th percentile (P < 0.001). All adolescents with BMI ≥40 kg/m² had a BMI ≥99th percentile. A total of 159/2,007 (8%) of 12–14.9‐year olds had a BMI ≥99th percentile compared with 77/1,213 (6%) 15–17.9‐year olds (P = 0.10), whereas 43/2,007 (2%) of 12–14.9‐year olds had a BMI ≥40 kg/m² compared with 45/1,213 (4%) 15–17.9‐year olds (P = 0.003). In summary, a relatively large proportion of adolescents from a diverse urban population would qualify for WLS based on the percentile criterion. Fewer adolescents would be eligible based on the adult WLS criterion, and younger adolescents would be less likely to be eligible for WLS than older adolescents.     

Body mass indices in patients with disabling hip osteoarthritis

Hip osteoarthritis (OA) is a degenerative joint disease that results in substantial morbidity. The disease may be preventable in some instances by reducing risk factors associated with the disease. We undertook a study to determine whether being overweight or obese, a health risk that applies to younger and older age groups, is commonly associated with hip joint OA. The body mass indices (BMIs) of 1021 males and females ranging in age from 23 to 94 years and requiring surgery for end-stage hip joint OA were analyzed to find the prevalence of high body weights at the time of surgery. Being overweight was defined as having a BMI of 25–29.9 kg/m² and being obese as having a BMI >30 kg/m². BMIs indicative of overweight were recorded for 68% of the patients surveyed. Of 35 patients aged 30–39 years, 53.3% had BMIs >25, with a mean of 28.8, which nearly reaches the lower limit defined for obesity. On average, patients who had had previous surgery and complications warranting reimplantation of new surgical devices had BMIs in the obese range. Our findings suggest that a high percentage of patients with end-stage hip OA are overweight, including younger adults and those with symptoms of 3–6 months' duration. Moreover, patients whose BMIs are in the obese range may be at increased risk for removal and reimplantation of their prosthesis.     

Clinical Profile and Management of Patients With Hypertension and Chronic Ischemic Heart Disease According to BMI

Obesity is associated with numerous risk factors and comorbidities such as hypertension, metabolic syndrome, type 2 diabetes, and cardiovascular diseases. However, numerous studies have reported an obesity paradox; the overweight and obese patients with established cardiovascular disease have better prognosis than those with a BMI <25 kg/m². This study was designed to assess potential differences in the clinical profile and management of hypertensive outpatients with chronic ischemic heart disease in obese and lean patients that could explain these two apparently contradictory points. Overweight and obesity were defined as a BMI 25–29.9 kg/m² and ≥30 kg/m², respectively. Cardiovascular risk factors goals were considered according to European Society of Hypertension‐European Society of Cardiology 2003, National Cholesterol Education Program Adult Treatment Panel III and American Diabetes Association 2005 guidelines. A sample of 2,024 patients (66.8 ± 10.1 years; 31.7% women) was included. Of these, 0.1% had a BMI <20 kg/m²; 17.1% BMI 20–24.9 kg/m²; 53.7% BMI 25–29.9 kg/m²; 23.7% BMI 30–34.9 kg/m²; 4.3% BMI 35–39.9 kg/m²; and 1.1% BMI ≥40 kg/m². The subgroup of patients with BMI ≥30 kg/m² had a higher proportion of women, diastolic dysfunction, diabetes, dyslipidemia, left ventricular hypertrophy, and heart failure. There was an inverse relationship between risk factors control rates and BMI (all comparisons BMI 20–24.9 kg/m² vs. 25–29.9 kg/m² vs. ≥30 kg/m²): blood pressure (BP) control (51.7% vs. 42.4% vs. 29.2%, P < 0.001); low‐density lipoprotein cholesterol (LDL‐C) control (35.2% vs. 30.5% vs. 27.9%, P = 0.03) and diabetes control (38.6% vs. 27.6% vs. 22.2%, P = 0.023). In conclusion, in patients with hypertension and chronic ischemic heart disease, as BMI increases, the clinical profile worsens as well as risk factors control rates.     

Weight Loss Expectations in Obese Patients Seeking Treatment at Medical Centers

Objective: To investigate weight loss expectations (expected 1‐year BMI loss, dream BMI, and maximum acceptable BMI) in obese patients seeking treatment and to examine whether expectations differ by sex, weight, diet and weight history, age, psychological factors, and primary motivations for weight loss. Research Methods and Procedures: 1891 obese patients seeking treatment in 25 Italian medical centers (1473 women; age, 44.7 ± 11.0 years; BMI, 38.2 ± 6.5 kg/m²) were evaluated. Diet and weight history, weight loss expectations, and primary motivation for seeking treatment (health or improving appearance) were systematically recorded. Psychiatric distress, binge eating, and body image dissatisfaction were tested by self‐administered questionnaires (Symptom CheckList‐90, Binge Eating Scale, and Body Uneasiness Test). Results: In 1011 cases (53.4%), 1‐year expected BMI loss was ≥9 kg/m², dream BMI was 26.0 ± 3.4 kg/m² (corresponding to a 32% loss), and maximum acceptable BMI was 29.3 ± 4.4 kg/m² (?23%). BMI and age were the strongest predictors of weight goals. Weight loss necessary to reach the desired targets was largely in excess of weight loss observed during previous dieting. Psychiatric distress, body dissatisfaction, and binge eating did not predict weight loss expectations. The primary motivation for weight loss was concern for future or present health; women seeking treatment to improve appearance had a lower grade of obesity, were younger, and had first attempted weight loss at a younger age. Discussion: Obese Italian patients had unrealistic weight loss expectations. There were significant disparities between patients’ perceptions and physicians’ weight loss recommendations of desirable treatment outcome.     

Obesity as an Obstetric Risk Factor: Does It Matter in a Perinatal Center?

Objectives: Obesity before and during pregnancy is associated with several obstetrics risk factors for both mother and fetus. The aim of this retrospective study was to analyze the influence of BMI before pregnancy on distinct perinatal parameters. Research Methods and Procedures: The study includes 5067 singleton pregnancies from 2001 to 2004 at the Department of Obstetrics and Gynecology, University of Leipzig. The study group was divided into BMI groups: <18.5, ≥18.5 to <25, ≥25 to <30, ≥30 to <35, ≥35 to <40, and ≥40 kg/m². Analysis of perinatal data included rate of intrauterine death, rate of cesarean section and shoulder dystocia, time of hospital stay for mother and newborn, and gestational age of delivery. Neonatal outcome variables included percentage of newborns weighing >4000 grams, rate of umbilical cord pH <7.10, and rate of 1‐, 5‐, and 10‐minute Apgar scores of <8. Results: There was no difference in the gestational age at delivery among the groups. In the group with BMI ≥30 kg/m², the cesarean section rate was significantly elevated to 25.1%, with a more dramatic increase up to 30.2% in the group with BMI ≥35 kg/m² and 43.1% in the group with BMI ≥40 kg/m², mainly because of a higher number of secondary cesarean sections. Although newborns of obese women showed worse initial neonatal adaptation, the 10‐minute Apgar values did not differ among the groups. The higher rate of operative deliveries and the trend to an increased rate of shoulder dystocia did not influence duration of the hospital stay for mothers and newborns or morbidity of both. Discussion: A high pre‐pregnancy BMI is clearly associated with a higher rate of cesarean section deliveries. However, under the compensating conditions of a tertiary perinatal center, overall morbidity of mothers and newborns seems not to be increased.     

Knee Structural Alteration and BMI: A Cross‐sectional Study

Objective: To describe the associations among BMI, knee cartilage morphology, and bone size in adults. Research Methods and Procedures: A cross‐sectional convenience sample of 372 male and female subjects (mean age, 45 years; range, 26 to 61 years) was studied. Knee articular cartilage defect score (0 to 4) and prevalence (defect score of ≥2), volume, and thickness, as well as bone surface area and/or volume, were determined at the patellar, tibial, and femoral sites using T1‐weighted fat‐saturation magnetic resonance imaging. Height, weight, BMI, and radiographic osteoarthritis were measured by standard protocols. Results: In multivariate analysis in the whole group, BMI was significantly associated with knee cartilage defect scores (β: +0.016/kg/m² to +0.083/kg/m², all p < 0.05) and prevalence (odds ratio: 1.05 to 1.12/kg/m², all p < 0.05 except for the lateral tibiofemoral compartment). In addition, BMI was negatively associated with patellar cartilage thickness only (β = ?0.021 mm/kg/m²; p = 0.039) and was positively associated with tibial bone area (medial: β = +7.1 mm²/kg/m², p = 0.001; lateral: β = +3.2 mm²/kg/m², p = 0.037). Those who were obese also had higher knee cartilage defect severity and prevalence and larger medial tibial bone area but no significant change in cartilage volume or thickness compared with those of normal weight. Discussion: This study suggests that knee cartilage defects and tibial bone enlargement are the main structural changes associated with increasing BMI particularly in women. Preventing these changes may prevent knee osteoarthritis in overweight and obese subjects.     

Obesity in South Africa: The South African Demographic and Health Survey

Objectives: To ascertain the anthropometric profile and determinants of obesity in South Africans who participated in the Demographic and Health Survey in 1998. Research Methods and Procedures: A sample of 13,089 men and women (age, ≥15 years) were randomly selected and then stratified by province and urban and nonurban areas. Height, weight, mid-upper arm circumference, and waist and hip circumference were measured. Body mass index (BMI) was used as an indicator of obesity, and the waist/hip ratio (WHR) was used as an indicator of abdominal obesity. Multivariate regression identified sociodemographic predictors of BMI and waist circumference in the data. Results: Mean BMI values for men and women were 22.9 kg/m² and 27.1 kg/m², respectively. For men, 29.2% were overweight or obese (≥25 kg/m²) and 9.2% had abdominal obesity (WHR ≥1.0), whereas 56.6% of women were overweight or obese and 42% had abdominal obesity (WHR >0.85). Underweight (BMI <18.5 kg/m²) was found in 12.2% of men and 5.6% of women. For men, 19% of the variation of BMI and 34% of the variation in waist circumference could be explained by age, level of education, population group, and area of residence. For women, these variables explained 16% of the variation of BMI and 24% of the variation in waist circumference. Obesity increased with age, and higher levels of obesity were found in urban African women. Discussion: Overnutrition is prevalent among adult South Africans, particularly women. Determinants of overnutrition include age, level of education, ethnicity, and area of residence.     

Vitamin D in Overweight/Obese Women and Its Relationship With Dietetic and Anthropometric Variables

Overweight/obese persons usually have an inadequate vitamin D status, a situation commonly made worse by an inadequate intake of this vitamin. For this reason, the aim of this study was to analyze dietetic and anthropometric differences in a group of young, overweight/obese Spanish women with respect to their vitamin D status. The study subjects were 66 white Spanish women (aged 20–35 years) with a BMI of 24–35 kg/m². Dietetic, anthropometric, and biochemical data were collected. Women were divided into two groups depending on their serum vitamin D concentrations: LD (women with <90 nmol/l 25(OH)D) and HD (women with ≥90 nmol/l 25(OH)D). The intakes of vitamin D, calcium, and supplements were similar in both groups. The body weight, BMI, and waist circumference of the HD subjects were smaller than those recorded for the LD subjects (68.6 ± 4.2 kg, 26.0 ± 1.3 kg/m², and 79.4 ± 3.4 cm compared to 76.2 ± 9.8, 28.6 ± 3.2 kg/m², and 86.2 ± 9.3 cm, respectively; P < 0.05). The hip circumference and the waist/hip ratio were similar in both groups. A BMI of <27.7 kg/m² (P50) was associated with serum vitamin D concentrations of ≥90 nmol/l (odds ratio = 0.1313; confidence interval: 0.0149–1.1599; P < 0.05). Overweight/obese women are at higher risk of vitamin D deficiency, largely due to excess adiposity rather than inadequate intake.     

Which Metric of Relative Weight Best Captures Body Fatness in Children?

Objective: To evaluate the relative merits of BMI (kilograms per meter squared) and age‐ and gender‐adjusted BMI, age‐ and gender‐specific z score of BMI, and age‐ and gender‐specific percentiles of BMI as surrogate measures of body fatness among a sample of youth. Research Methods and Procedures: The sample comprised 596 children and adolescents 5 to 18.7 years old and was 40% male and 55% white. Height and weight were measured by trained research staff. DXA was used to determine body fat mass. BMI, age‐ and gender‐specific percentile of BMI, and age‐ and gender‐specific z scores of BMI were computed, and these metrics were compared with measured body fatness. Results: The BMI values in the sample ranged from 12.9 to 55.0 kg/m², with a mean of 24.9 kg/m². The Spearman correlations with percentage body fat were similar for all of the BMI metrics (r = 0.82 to 0.88). Linear regression models with age‐ and gender‐specific percentiles of BMI explained significantly less of the variance (65%) than models with log‐transformed BMI (81%) or age‐ and gender‐specific z scores of BMI (75% to 79%). z scores were the most accurate at classifying children who were overfat (sensitivity = 0.84, specificity = 0.96 for z score ≥1). However, using a BMI ≥85th percentile or a BMI ≥20 kg/m² was also accurate at classifying youth. Discussion: The BMI metrics had similar correlations with body fatness, but age‐ and gender‐specific percentiles of BMI were the least accurate proxy measure of body fatness. However, a BMI z score ≥1, BMI percentile ≥85, and BMI ≥20 kg/m² are all useful for identifying children who may be overfat.     

Prevalence of Obstructive Sleep Apnea Determined by the Watchpat in Nonobese Japanese Patients with Poor Glucose Control And Type 2 Diabetes

Objective: Diagnosing obstructive sleep apnea (OSA) usually involves high cost, patient inconvenience, and the need for examination at a specialized center. This study employed a portable, wearable, diagnostic device (WatchPAT) to investigate the prevalence of OSA in nonobese Japanese patients with type 2 diabetes.Methods: Patients with type 2 diabetes were tested for OSA over one night using the WatchPAT. Logistic regression analysis was used to estimate the odds ratios (ORs) of risk factors for OSA in nonobese subjects.Results: A total of 200 eligible patients with type 2 diabetes were studied (64.5% men; aged 60.1 ± 13.6 years; body mass index &lsqb;BMI], 26.3 ± 5.2 kg/m²). When OSA was defined as apnea-hypopnea index ≥5/hour, its prevalence was 80.5%. The prevalence of OSA in subjects with a BMI <20 kg/m², ≥20 and <25 kg/m², ≥25 and <30 kg/m², and ≥30 kg/m² was 38.9%, 73.5%, 86.5%, and 97.5%, respectively. The severity of OSA increased in proportion to BMI, especially when the BMI was >25 kg/m². The prevalence of OSA was also high (66.3%) in normal-weight subjects (BMI <25 kg/m²). Furthermore, the serum triglyceride level (OR, 1.01; 95% confidence interval, 1.00 to 1.02; P = .042) was significantly related to OSA.Conclusion: A high prevalence of OSA was observed in this nonobese population of Japanese patients with type 2 diabetes. The triglyceride level was associated with OSA among nonobese patients.Abbreviations: AHI = apnea-hypopnea Index; BMI = body mass index; CI = confidence interval; ESS = Epworth Sleepiness Scale; HbA1c = glycated hemoglobin; OR = odds ratio; OSA = obstructive sleep apnea; PAT = peripheral arterial tone; T2D = type 2 diabetes; TG = triglyceride     

Effects of Obesity on the Conversion from Normal Glucose Tolerance to Diabetes in Hong Kong Chinese

Objective: To assess the effects of BMI on progression to diabetes in Hong Kong Chinese and to analyze the optimal cutoff for overweight and obesity in Hong Kong Chinese. Research Methods and Procedures: This is a prospective study with a mean follow‐up of 2.1 years (median 1.4 years, range 0.9 to 8.4 years). We recruited 172 nondiabetic high‐risk subjects, of whom 115 had normal glucose tolerance (NGT) and 57 had impaired glucose tolerance (IGT). BMI and 75‐gram oral glucose tolerance tests were assessed at baseline and then at yearly intervals Results: The crude rates of progression to diabetes for subjects with NGT or IGT were 8.4% and 11.5% per year, respectively. For subjects with NGT, the progression rate to diabetes differed with different BMI ranges. For subjects with NGT and BMI ≥ 25 kg/m², the crude rates of progression to diabetes or glucose intolerance (diabetes or IGT) were 12.5% per year and 14.6% per year, respectively. The corresponding rates for subjects with NGT and BMI ≥ 28 kg/m² were 14.6% and 18.9% per year, respectively. Among subjects with NGT, those with BMI between 25 and 28 kg/m² had the highest Youden index and likelihood ratio to predict the conversion to diabetes or glucose intolerance. Discussion: Obese subjects with NGT had higher rates of progression to diabetes than nonobese subjects. We recommend redefining BMI cutoffs, with 23 kg/m² for overweight and 28 kg/m² for obesity. This definition may be more sensitive to identify at‐risk subjects and more specific to identify “patients” for therapeutic management.     

Appropriateness Criteria for Bariatric Surgery: Beyond the NIH Guidelines

Careful selection of bariatric patients is critical for successful outcomes. In 1991, the NIH first established patient selection guidelines; however, some surgeons operate on individuals outside of these criteria, i.e., extreme age groups. We developed appropriateness criteria for the spectrum of patient characteristics including age, BMI, and severity of eight obesity‐related comorbidities. Candidate criteria were developed using combinations of patient characteristics including BMI: ≥40 kg/m², 35–39, 32–34, 30–31, <30; age: 12–18, 19–55, 56–64, 65+ years old; and comorbidities: prediabetes, diabetes, hypertension, dyslipidemia, sleep apnea, venous stasis disease, chronic joint pain, and gastroesophageal reflux (plus severity level). Criteria were formally validated on their appropriateness of whether the benefits of surgery clearly outweighed the risks, by an expert panel using the RAND/UCLA modified Delphi method. Nearly all comorbidity severity criteria for patients with BMI ≥40 kg/m² or BMI = 35–39 kg/m² in intermediate age groups were found to be appropriate for surgery. In contrast, patients in the extreme age categories were considered appropriate surgical candidates under fewer conditions, primarily the more severe comorbidities, such as diabetes and hypertension. For patients with a BMI of 32–34, only the most severe category of diabetes (Hgb A1c >9, on maximal medical therapy), is an appropriate criterion for those aged 19–64, whereas many mild to moderate severity comorbidity categories are “inappropriate.” There is overwhelming agreement among the panelists that the current evidence does not support performing bariatric surgery in lower BMI individuals (BMI <32). This is the first development of appropriateness criteria for bariatric surgery that includes severity categories of comorbidities. Only for the most severe degrees of comorbidities were adolescent and elderly patients deemed appropriate for surgery. Patient selection for bariatric procedures should include consideration of both patient age and comorbidity severity.     

Long-Term,Sustained, Lifestyle-Induced Weight Loss in Severe Obesity: the Get-Real Program

Objective: To study the long-term effectiveness of a patient-centered, multidisciplinary lifestyle intervention treatment in patients medically eligible for bariatric surgery.Methods: Using a case-control study design, we compared treatment results for 98 adults (mean body mass index [BMI], 44.2 kg/m²) with the outcomes of 148 controls (mean BMI, 43.0 kg/m²) receiving standard care. The approach included a phased triage for inclusion, followed by 12 lifestyle intervention group sessions alternating with individual visits for behavior, diet, and exercise instructions.Results: At 2 years, weight loss averaged 15.3 ± 1.4 kg (P<.0010) (12 ± 1% of initial body weight [IBW], P<.001; 21 ± 2% of excess body weight [EBW], P<.001) in an intention-to-treat (ITT) analysis; in completers, weight loss was 18.8 ± 1.5 kg (P<.001) (15 ± 1% IBW, P<.001; 26 ± 3% EBW, P<.001). A total of 42 patients lost ≥10% IBW. Controls remained weight stable (P =.35); 3% lost ≥10% IBW. Patients achieving weight loss that would be considered satisfactory for bariatric surgery included 20% who achieved ≥35% EBW loss, 29% who achieved a BMI <35 kg/m² (if starting BMI <50 kg/m²) or BMI <40 kg/m² (if starting BMI ≥50 kg/m²), and 37% who achieved EBW loss ≤50%. These values for completers were 31, 39, and 48%, respectively. In the 55 patients starting the program ≥4 years ago, weight loss maintenance of 12 ± 1% IBW (ITT, 16 ± 1% in completers) was observed.Conclusion: Substantial nonsurgical weight loss, maintained at 2 to 4 years, is achievable in severely obese patients using comprehensive lifestyle approaches; the efficacy/safety trade-off in obesity treatment is an important consideration in interpreting these results.Abbreviations: BMI = body mass index EBW = excess body weight HbA_1c = glycated hemoglobin IBW = initial body weight LOCFA = last observation carried forward analysis