Maternal serum leptin during pregnancy and infant birth weight: The influence of maternal overweight and obesity

Objective:

Few studies have examined whether the distinct metabolic patterns found in obese and nonobese pregnant women have different effects on the growing fetus. Our objective was to estimate the influence of longitudinal variation in maternal serum leptin levels on variation in infant birth weight in overweight/obese versus normal‐weight women.

Design and Methods:

In a prospective cohort of 286 gravidas, maternal weight and serum leptin levels at 6–10, 10–14, 16–20, 22–26, and 32–36 weeks gestation were measured. Effects of leptin levels on infant birth weight adjusted for gestational age at delivery (aBW) were analyzed using a linear regression model that accounted for the relationship of time‐varying predictors to the log‐transformed leptin concentrations.

Results:

Different relationships of aBW to maternal serum leptin and its rate of change across pregnancy were exhibited by overweight/obese and normal‐weight gravidas. For normal‐weight women, aBW is not associated with either the magnitude of the logarithm of the leptin concentration or with its rate of change in either the first or second half of pregnancy. Conversely, for overweight/obese women, an increase in the rate of change in maternal serum leptin in the second half of pregnancy is significantly associated with a decrease in aBW. This effect is distinct from that of maternal weight.

Conclusion:

Differences in the effect of maternal serum leptin on fetal growth between overweight/ obese and normal‐weight women suggest metabolic and physiologic heterogeneity between these groups. Such differences may be involved in the long‐term physiologic effects of the obese intrauterine environment on the health of the offspring.     

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.     

Primary antiphospholipid antibody syndrome—one further aspect of thrombophilia in overweight and obese patients with venous thromboembolism

Objective: Overweight and obesity are established risk factors for venous thromboembolism (VTE). We examined the difference in the frequency of primary antiphospholipid antibody syndrome (PAPS) in VTE patients according to their BMI. Design and Methods: We included 998 VTE patients treated at our institution between 2009 and 2011 in a retrospective data analysis. Thrombophilia screening including evaluation for APS (lupus anticoagulant, anti‐cardiolipin, and anti‐B2‐glycoprotein‐I IgG and IgM antibodies) was performed in all patients. Results: PAPS was diagnosed in 6.8% (24/355) of normal weight (BMI < 24 kg/m²) VTE patients, in 11.1% (50/452) of overweight (BMI 25–30 kg/m²) VTE patients, and in 15.7% (30/191) of obese (BMI > 31 kg/m²) VTE patients. The difference of PAPS occurrence between these groups was statistically significant (P = 0.001). PAPS patients demonstrated higher fibrinogen levels as compared to non‐PAPS patients (median 416.0 md/dl vs. 352.0 mg/dl, P = 0.001). Furthermore, fibrinogen levels increased significantly according to the body weight of patients (median normal weight patients 330.0 mg/dl vs. overweight patients 359.0 mg/dl vs. obese patients 415.0 mg/dl, P = 0.001). Conclusion: PAPS seems to be more frequent in overweight and obese patients. As PAPS patients showed significantly higher fibrinogen levels and as fibrinogen levels increased significantly according to the body weight of patients, an elevated inflammatory state in overweight and obese patients as a reason for the increased PAPS occurrence can be assumed.     

Characteristics Associated With Fasting Appetite Hormones (Obestatin,Ghrelin, and Leptin)

Obestatin, derived from the same gene as the hunger hormone ghrelin, may reduce food intake in animals. The role of obestatin in human physiology is unclear. We evaluated cross‐sectional associations between participant characteristics and fasting levels of obestatin as well two other hormones associated with energy balance, ghrelin and leptin. Data are from the baseline visit of the Optimal Macronutrient Intake Trial to Prevent Heart Disease (OMNI‐Heart) Trial that enrolled adults with elevated blood pressure (systolic 120–159 mm Hg or a diastolic of 80–99 mm Hg) but who were otherwise healthy. Partial Spearman's correlations and linear regression models estimated the association between age, gender, BMI, physical activity, and smoking with fasting hormones. Obestatin was directly associated with ghrelin (r = 0.45, P < 0.05). On average, overweight (BMI 25–30) and obese (BMI > 30) individuals had obestatin concentrations that were 12.6 (s.d. 8.8) and 25.4 (s.d. 8.4) pg/ml lower compared to normal weight (BMI < 25) individuals, respectively (P for trend = 0.002). Overweight (BMI 25–30) and obese (BMI > 30) individuals had ghrelin concentrations that were 161.7 (s.d. 69.6) and 284.7 (s.d. 66.5) pg/ml lower compared to normal weight (BMI < 25) individuals, respectively (P for trend <0.0001). A 5 unit increase in BMI was associated with 41.3% (s.d. 4.3%) (P < 0.0001) higher leptin. Obestatin and ghrelin are directly correlated and share the same patterns of association with participant characteristics. Modifiable risk factors for chronic diseases, such as BMI, are associated with fasting levels of leptin, obestatin, and ghrelin.     

Optimizing healthy gestational weight gain in women at high risk of gestational diabetes: A randomized controlled trial

Objective:

Optimizing gestational weight gain (GWG) in early pregnancy is of clinical and public health importance, especially in higher risk pregnancies.

Design and Methods:

In a robustly designed, randomized controlled trial, 228 pregnant women at risk of developing gestational diabetes mellitus (GDM) were allocated to either control (written health information only) or intervention (four‐session lifestyle program). All women received standard maternal care. Measures were completed at 12‐15 and 26‐28 weeks gestation. Measures included anthropometrics (weight and height), physical activity (pedometer and International Physical Activity Questionnaire), questionnaires (risk perception), and GDM screening.

Results:

The mean (SD) age [31.7 (4.5) and 32.4 (4.7) years] and body mass index [BMI; 30.3 (5.9) and 30.4 (5.6) kg/m²] were similar between control and intervention groups, respectively. By 28 weeks, GWG was significantly different between control and intervention groups [6.9 (3.3) vs. 6.0 (2.8) kg, P < 0.05]. When stratified according to baseline BMI, overweight women in the control group gained significantly more weight compared to overweight women in the intervention group [7.8 (3.4) vs. 6.0 (2.2) kg, P < 0.05], yet in obese women, GWG was similar in both groups. Physical activity levels declined by 28 weeks gestation overall (P < 0.01); however, the intervention group retained a 20% higher step count compared to controls [5,203 (3,368) vs. 4,140 (2,420) steps/day, P < 0.05]. Overall, GDM prevalence was 22%, with a trend toward less cases in the intervention group (P = 0.1).

Conclusions:

Results indicate that a low‐intensity lifestyle intervention, integrated with antenatal care, optimizes healthy GWG and attenuates physical activity decline in early pregnancy. Efficacy in limiting weight gain was greatest in overweight women and in high‐risk ethnically diverse women.     

Transition from overweight to obesity worsens pregnancy outcome in a BMI-dependent manner

Objective: To assess pregnancy outcomes in different BMI groups. Research Methods and Procedures: We analyzed 25, 601 singleton pregnancies from January 1989 to December 2001. Overweight women (prepregnancy BMI = 26 to 29 kg/m²) represented 13.2% (3388) of the cases, and 7.3% (1880) were obese (BMI ≥ 30 kg/m²). The data were obtained from self‐administered questionnaires at 20 weeks of pregnancy, complemented by nurse interviews and clinical records. Multiple logistic regression analysis was used to control for confounding factors. Results: Overweight and obese women had more previous deliveries, pregnancy terminations, miscarriages, and stillbirths, to have more diabetes and hypertension, and to smoke more often than normal weight women. The pregnancies were more often complicated by preeclampsia or chorioamnionitis (p < 0.001). Pregnancy outcomes were impaired in overweight and obese pregnant women, with respective odds ratios (95% confidence index) as follows: low Apgar score at 5 minutes, 1.54 (1.20 to 1.98) and 1.64 (1.22 to 2.28); newborn admission to a neonatal unit, 1.20 (1.06 to 1.37) and 1.38 (1.17 to 1.61); cesarean delivery, 1.22 (1.10 to 1.35) and 1.68 (1.48 to 1.91); fetal death, 1.54 (0.88 to 2.68) and 2.35 (1.28 to 4.32); perinatal death, 1.54 (0.98 to 2.42) and 2.19 (1.33 to 3.62). Discussion: Obesity, in particular during pregnancy, should be considered as an abnormal situation. An overweight condition increases obstetric risks in a BMI‐dependent manner. The risk of perinatal death more than doubles in the transition from an overweight to an obese condition. Modest weight loss could bring substantial advantages to obstetric outcome.     

Leptin Responses to Weight Loss in Postmenopausal Women: Relationship to Sex‐Hormone Binding Globulin and Visceral Obesity

Objective: Leptin concentrations increase with obesity and tend to decrease with weight loss. However, there is large variation in the response of serum leptin levels to decreases in body weight. This study examines which endocrine and body composition factors are related to changes in leptin concentrations following weight loss in obese, postmenopausal women. Research Methods and Procedures: Body composition (DXA), visceral obesity (computed tomography), leptin, cortisol, insulin, and sex hormone‐binding globulin (SHBG) concentrations were measured in 54 obese (body mass index [BMI] = 32.0 ± 4.5 kg/m²; mean ± SD), women (60 ± 6 years) before and after a 6‐month hypocaloric diet (250 to 350 kcal/day deficit). Results: Body weight decreased by 5.8 ± 3.4 kg (7.1%) and leptin levels decreased by 6.6 ± 11.9 ng/mL (14.5%) after the 6‐month treatment. Insulin levels decreased 10% (p < 0.05), but mean SHBG and cortisol levels did not change significantly. Relative changes in leptin with weight loss correlated positively with relative changes in body weight (r = 0.50, p < 0.0001), fat mass (r = 0.38, p < 0.01), subcutaneous fat area (r = 0.52, p < 0.0001), and with baseline values of SHBG (r = 0.38, p < 0.01) and baseline intra‐abdominal fat area (r = ?0.27, p < 0.06). Stepwise multiple regression analysis showed that baseline SHBG levels (r² = 0.24, p < 0.01), relative changes in body weight (cumulative r² = 0.40, p < 0.05), and baseline intra‐abdominal fat area (cumulative r² = 0.48, p < 0.05) were the only independent predictors of the relative change in leptin, accounting for 48% of the variance. Discussion: These results suggest that obese, postmenopausal women with a lower initial SHBG and more visceral obesity have a greater decrease in leptin with weight loss, independent of the amount of weight lost.     

Evaluation of Oxidative Stress in Overweight Subjects With or Without Metabolic Syndrome

Although oxidative stress is considered the underlying mechanism by which dysfunctional metabolism occurs in obese subjects, there are few studies on oxidative stress in overweight subjects. The objective of this study was to verify the influence of metabolic syndrome (MetS) on oxidative stress and antioxidant defense in overweight subjects. There were 123 subjects (50 in the control group and 73 in the overweight group) chosen to participate in this cross‐sectional study. The control group included 50 healthy individuals with a BMI between 20 and 24.9 kg/m² and without MetS. The overweight group included 73 subjects with a BMI between 25 and 29.9 kg/m². Overweight subjects were divided into two groups: with MetS (29 subjects) and without MetS (44 subjects). Control group and overweight group subjects without MetS showed no differences in oxidative stress parameters and total antioxidant capacity (TRAP). Overweight subjects with MetS had higher hydroperoxide concentrations measured by chemiluminescence compared to the control group (P < 0.05), higher hydroperoxide and hydrogen peroxide concentrations determined by ferrous oxidation‐xylenol orange assay compared to overweight subjects without MetS (P < 0.001), and higher advanced oxidation protein product (AOPP) concentrations (P < 0.001) compared to the other groups. AOPP was directly correlated with uric acid concentrations. Overweight subjects with MetS had lower TRAP concentrations compared to the control group (P < 0.001). In conclusion, this study showed that overweight subjects with MetS, in contrast to overweight subjects without MetS, have a redox imbalance characterized by increased plasma oxidation and reduced antioxidant capacity.     

Overweight Children's Barriers to and Support for Physical Activity

Objective: As the epidemic of overweight increases among youth, research needs to examine factors that may influence children's participation in weight‐related health behaviors. This study examined overweight children's perceived barriers to and support for physical activity compared with nonoverweight children. Research Methods and Procedures: Barriers to and support for physical activity were examined among 84 overweight children attending a summer fitness camp or a university‐based weight loss clinic. Barriers and support levels were then compared with those of 80 nonoverweight children of a similar age range. Results: Body‐related barriers were the most predominant barrier type among overweight youth, especially among overweight girls. Overweight children, particularly girls, reported significantly higher body‐related, resource, and social barriers to physical activity compared with nonoverweight children and lower levels of adult support for physical activity. Discussion: Overweight children may be particularly vulnerable to body‐related barriers to physical activity, and reducing such barriers may serve as physical activity intervention points most relevant for overweight youth. Future interventions may also benefit from enhancing support for physical activity from adults and peers.     

Overweight and Obesity: Prediction by Silhouettes in Young Adults

The present study analyzes the prevalence of overweight/obesity in a sample of young adults from the University of the Basque Country (Spain), and tests the efficiency of the silhouettes to predict overweight/obesity. This cross‐sectional study was conducted in a sample of volunteer university students from the University of the Basque Country (356 men and 745 women, age: 18–33 years), who came to the Physical Anthropology laboratory where a standardized questionnaire was administered and anthropometric measurements were taken by a well‐trained anthropometrist. Height and weight were obtained. BMI was calculated as weight/height² (kg/m²) and it was used as a reference method. Using a questionnaire, based on the standard figural stimuli, subjects were asked to choose the silhouette which was closest to his/her usual appearance (current body size). The accuracy of the Williamson et al.'s silhouettes as an overweight‐obesity indicator was analyzed by gender‐specific receiver operating curve (ROC). The cutoff figure to distinguish between nonoverweight and overweight‐obese individuals corresponded to number 7 in men and 6 in women. These cutoff values matched optimal sensitivity and specificity, with few nonoverweight subjects selecting silhouettes bigger than 7 in the case of men or 6 for women. In conclusion, the figural stimuli allows the identification of populations at overweight/obesity risk with the simple use of silhouettes, at least in this rank of age, where the overweight and obesity are yet little frequent.     

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.     

Stigmatized Students: Age,Sex, and Ethnicity Effects in the Stigmatization of Obesity

Objective: To assess the stigmatization of obesity relative to the stigmatization of various disabilities among young men and women. Attitudes across ethnic groups were compared. In addition, these findings were compared with data showing severe stigmatization of obesity among children. Research Methods and Procedures: Participants included 356 university students (56% women; mean age, 20.6 years; mean BMI, 23.3 kg/m²; range, 14.4 to 45.0 kg/m²) who ranked six drawings of same‐sex peers in order of how well they liked each person. The drawings showed adults with obesity, various disabilities, or no disability. These rankings were compared with those obtained through a similar procedure with 458 fifth‐ and sixth‐grade children. Results: Obesity was highly stigmatized relative to physical disabilities. African‐American women liked obese peers more than did African‐American men, white men, or white women [F (1, 216) = 4.02, p < 0.05]. Overweight and obese participants were no less stigmatizing of obesity than normal weight participants. Adults were more accepting than children of their obese peers [t (761) = 9.16, p < 0.001]. Discussion: Although the stigmatization of obesity was high among participants overall, African‐American women seemed to have more positive attitudes toward obesity than did white women, white men, or African‐American men. Participants’ weight did not affect their stigmatization of obesity: obese and overweight adults were as highly stigmatizing of obesity as non‐overweight adults. Such internalized stigmatization could help to explain the low self‐esteem and poor body image among obese young adults. However, adults seemed to have more positive attitudes about obesity than children. An understanding of the factors that limit the stigma of obesity among African‐American women could help efforts to reduce stigma.     

Fat mass limits lower-extremity relative strength and maximal walking performance in older women

The purpose of this study was to determine if excess fat negatively affects relative strength and walking gait performance in overweight, older women. Twenty-five older women (65–80 yr) were separated into normal weight (BMI < 25 kg m⁻², n = 11) and overweight groups (BMI ? 25 kg m⁻², n = 14). Strength and rate of torque development (RTD) of the knee extensors and flexors, ankle plantarflexors and dorsiflexors were measured. Participants walked at standard and maximal speeds during which muscle activation, spatiotemporal and kinetic gait variables were measured. Relative to mass, overweight older women had 24% lower maximal torque and 38% lower RTD than normal weight women. Maximal walking speed was slower in overweight (1.25 ± 0.22 vs. 1.54 ± 0.25 m s⁻¹, P = 0.004) and was correlated to strength (r = 0.53, P < 0.01) and fat mass (r = −0.65, P = 0.001). At maximal speed, overweight had 11% lower vertical ground reaction force relative to mass, 8% slower stride rate, 12% shorter strides, 13% longer foot–ground contact times, 21% longer double-limb support times, 65% greater knee extensor and 78% greater plantarflexor activation (P < 0.05). Overweight, older women demonstrated altered gait and reduced walking performance related to poor relative strength and rate of torque development of lower-extremity muscles.     

Maternal inflammatory diet and adverse pregnancy outcomes: Circulating cytokines and genomic imprinting as potential regulators?

Excessive inflammation during pregnancy alters homeostatic mechanisms of the developing fetus and has been linked to adverse pregnancy outcomes. An anti-inflammatory diet could be a promising avenue to combat the pro-inflammatory state of pregnancy, particularly in obese women, but we lack mechanistic data linking this dietary pattern during pregnancy to inflammation and birth outcomes. In an ethnically diverse cohort of 1057 mother-child pairs, we estimated the relationships between dietary inflammatory potential [measured via the energy-adjusted dietary inflammatory index (E-DII?)] and birth outcomes overall, as well as by offspring sex and maternal pre-pregnancy body mass index (BMI). In a subset of women, we also explored associations between E-DII, circulating cytokines (n = 105), and offspring methylation (n = 338) as potential modulators of these relationships using linear regression. Adjusted regression models revealed that women with pro-inflammatory diets had elevated rates of preterm birth among female offspring [β = ?0.22, standard error (SE) = 0.07, P<0.01], but not male offspring (β=0.09, SE = 0.06, P<0.12) (P_interaction = 0.003). Similarly, we observed pro-inflammatory diets were associated with higher rates of caesarean delivery among obese women (β = 0.17, SE = 0.08, P = 0.03), but not among women with BMI <25 kg/m² (P_interaction = 0.02). We observed consistent inverse associations between maternal inflammatory cytokine concentrations (IL-12, IL-17, IL-4, IL-6, and TNFα) and lower methylation at the MEG3 regulatory sequence (P<0.05); however, results did not support the link between maternal E-DII and circulating cytokines. We replicate work by others on the association between maternal inflammatory diet and adverse pregnancy outcomes and provide the first empirical evidence supporting the inverse association between circulating cytokine concentrations and offspring methylation.     

Plasma Leptin Response to an Epinephrine Infusion in Lean and Obese Women

Objective: Because leptin production by adipose tissue is under hormonal control, we examined the impact of epinephrine administration on plasma leptin concentrations. Research Methods and Procedures: We measured plasma leptin, insulin, and free fatty acid (FFA) responses after a 60-minute epinephrine infusion (0.010 μg/kg fat free mass/min) followed by a 30-minute recovery period (no infusion) in a group of 11 lean (mean body mass index ± SD: 22.6 ± 1.1 kg/m²) and 15 obese (30.0 ± 1.3 kg/m²) premenopausal women. Leptin, insulin, and FFA levels were measured in plasma before (−15 and 0 minutes) and at every 30 minutes over the 90-minute period. Results: In both lean and obese individuals, plasma leptin was significantly reduced by epinephrine (p < 0.0001). Body fat mass was associated with fasting leptin levels (r = 0.64, p < 0.0005) as well as with the decrease in leptinemia (r = −0.51, p < 0.01) produced by epinephrine administration. Furthermore, we noted a large range of leptin response to epinephrine among our subjects, especially in obese women (from −12 to −570 ng/mL per 60 minutes). However, there was no association between postepinephrine leptin and FFA levels (r = −0.14, p = 0.55). Discussion: Results of this study indicate that leptin levels decrease after epinephrine administration in both lean and obese premenopausal women. However, the heterogeneity in the response of leptin to catecholamines suggests potential alterations of the leptin axis that may contribute to generate a positive energy balance and, thus, may favor weight gain in some obese individuals.     

Overweight,Waist Circumference,Age, Gender,and Insulin Resistance as Risk Factors for Hyperleptinemia

Objective: To evaluate the influence of overweight, waist circumference, age, gender, and insulin resistance as risk factors for hyperleptinemia. Research Methods and Procedures: A cross‐sectional study was carried out in a population of 197 subjects: 59 men (21 aged <60 years and 38 aged ≥60 years) and 138 women (37 aged <60 years and 101 aged ≥60 years). The groups were stratified by overweight and normal weight. After a 12‐hour fasting period, we measured serum leptin and insulin levels with radioimmunoassay methods. We also measured serum glucose and lipid profile. The data were analyzed by means of comparative tests. A variance‐stabilizing transformation (natural logarithmic) was used to meet multiple linear regression, analysis of covariance, and logistic regression models. Results: The leptin serum levels were higher and statistically significant in young and older women than they were in men. We observed an interaction between gender and body mass index to explain the difference in leptin levels (p < 0.0001). Our study demonstrated an inverse relationship between leptin with age and high‐density lipoprotein cholesterol. In logistic regression analysis, the overweight × gender interaction and waist circumference have a statistically significant influence as independent variables on hyperleptinemia (overweight × gender odds ratio = 6.81; 95% confidence interval, 1.10 to 46.86; p < 0.05 and waist circumference odds ratio = 4.34; 95% confidence interval, 1.47 to 12.83; p = 0.001). Discussion: Women who were overweight or had a higher waist circumference (women ≥ 88 cm and men ≥ 102 cm) have a significantly higher risk of having hyperleptinemia. The increase in age as an isolated variable is not a risk factor for hyperleptinemia.     

Obesity and Medicare Expenditure: Accounting for Age‐Related Height Loss

To determine the relationship between BMI and Medicare expenditure for adults 65‐years and older and determine whether this relationship changes after accounting for misclassification due to age‐related height loss. Using a cross sectional study design, the relationship between BMI and fee‐for‐service Medicare expenditure was examined among beneficiaries who completed the Medicare Current Beneficiary Survey (MCBS) in 2002, were not enrolled in Medicare Health Maintenance Organization, had a self‐reported height and weight, and were 65 and older (n = 7,706). Subjects were classified as underweight, normal weight, overweight, obese (obese I), and severely obese (obese II/III). To adjust BMI for the artifactual increase associated with age‐related height loss, the reported height was transformed by adding the sex‐specific age‐associated height loss to the reported height in MCBS. The main outcome variable was total Medicare expenditure. There was a significant U‐shaped pattern between unadjusted BMI and Medicare expenditure: underweight $4,581 (P < 0.0003), normal weight $3,744 (P < 0.0000), overweight $3,115 (reference), obese I $3,686 (P < 0.0039), and obese II/III $4,386 (P < 0.0000). This pattern persisted after accounting for height loss: underweight $4,640 (P < 0.0000), normal weight $3,451 (P < 0.0507), overweight $3,165 (reference), obese I $3,915 (P < 0.0010), and obese II/III $4,385 (P < 0.0004) compared to overweight. In older adults, minimal cost is not found at “normal” BMI, but rather in overweight subjects with higher spending in the obese and underweight categories. Adjusting for loss‐of‐height with aging had little affect on cost estimates.     

Utility of Childhood BMI in the Prediction of Adulthood Disease: Comparison of National and International References

Objective: To determine whether the U.S. Centers for Disease Control and Prevention (CDC; CDC Reference) or International Obesity Task Force (IOTF; IOTF Reference) BMI cut‐off points for classifying adiposity status in children are more effective at predicting future health risk. Research Methods and Procedures: The sample (N = 1709) included 4‐ to 15‐year‐old (at baseline) boys and girls from the Bogalusa Heart Study. Overweight and obesity status were determined using both the CDC Reference and IOTF Reference BMI cut‐off points at baseline. The ability of childhood overweight and obesity, determined from the two BMI classification systems, to predict obesity and metabolic disorders in young adulthood (after a 13‐ to 24‐year follow‐up) was then compared. Results: Independently of the classification system employed to determine adiposity based on childhood BMI, the odds of being obese and having all of the metabolic disorders in young adulthood were significantly (p < 0.05) higher in the overweight and obese groups by comparison with the nonoverweight groups. Childhood overweight and obesity, determined by both the CDC Reference and IOTF Reference, had a low sensitivity and a high specificity for predicting obesity and metabolic disorders in young adulthood. Overweight and obesity as determined by the CDC Reference were slightly more sensitive and slightly less specific than the corresponding values based on the IOTF Reference. Discussion: Overweight and obesity during childhood, as determined by both the CDC and IOTF BMI cut‐off points, are strong predictors of obesity and coronary heart disease risk factors in young adulthood. The differences in the predictive capacity of the CDC Reference and IOTF Reference are, however, minimal.     

Maternal serum lipids during pregnancy and infant birth weight: the influence of prepregnancy BMI

Maternal obesity may be associated with metabolic factors that affect the intrauterine environment, fetal growth, and the offspring's long-term risk for chronic disease. Among these factors, maternal serum lipids play a particularly important role. Our objective was to estimate the influence of variation in maternal serum lipid levels on variation in infant birth weight (BW) in overweight/obese and normal weight women. In a prospective cohort of 143 gravidas, we measured maternal serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) at 6-10, 10-14, 16-20, 22-26, and 32-36 weeks gestation. Effects of maternal serum lipid levels on infant BW adjusted for gestational age at delivery (aBW) were analyzed using linear regression models. In analyses stratified by maternal prepregnancy BMI categorized as normal (≤25.0 kg/m(2)) and overweight/obese (>25.0 kg/m(2)), we found a significant (P < 0.05) inverse association between aBW and HDL-C at all time points starting at 10 weeks gestation in overweight/obese women. No significant effect was found in normal weight women. In contrast, increased maternal serum TG was significantly associated with increased aBW only for normal weight women at 10-14 and 22-26 weeks gestation. Variation in aBW is not associated with variation in maternal serum TC or LDL-C for either stratum at any time point. We postulate that such differences may be involved in the "physiological programming" that influences later risk of chronic disease in the infants of overweight/obese mothers.     

Weight Loss Is Associated With Increased Serum 25‐Hydroxyvitamin D in Overweight or Obese Women

Low circulating concentrations of vitamin D metabolites have been associated with increased risk for several diseases and clinical conditions. Large observational studies and surveys have shown that obesity is independently associated with lower serum 25‐hydroxyvitamin D (25(OH)D) concentration. Few studies have examined the effect of weight loss on serum 25(OH)D concentration. The purpose of this study was to prospectively examine the effect of weight loss on serum 25(OH)D concentration. Data were collected from 383 overweight or obese women who participated in a 2‐year clinical trial of a weight‐loss program, in which 51% (N = 195) lost at least 5% of baseline weight by 24 months, 18% (N = 67) lost 5–10%, and 33% (N = 128) lost >10%. Women who did not lose weight at 24 months had an increase in serum 25(OH)D of 1.9 (9.7) ng/ml (mean (SD)); 25(OH)D increased by 2.7 (9.1) ng/ml for those who lost 5–10% of baseline weight; and 25(OH)D increased by 5.0 (9.2) ng/ml for those who lost >10% of baseline weight (P = 0.014). At baseline, 51% (N = 197) of participants met or exceeded the recommended serum concentration of 20 ng/ml. By study end, 64% (N = 230) of overweight or obese women met this goal, as well as 83% (N = 20) of those whose weight loss achieved a normal BMI. These findings suggest that weight loss, presumably associated with a reduction in body fat, is associated with increased serum 25(OH)D concentration in overweight or obese women.