Extreme Values Of Body Mass Index Research Articles

The effect of body mass index on clinical outcomes in patients with newly diagnosed atrial fibrillation in the GARFIELD-AF registry

Abstract Introduction Higher body mass index (BMI) is associated with a higher risk of atrial fibrillation (AF). However, previous evidence has suggested an inverse association between BMI and risk of AF outcomes. Purpose To explore the association between BMI and outcomes in those with newly diagnosed AF in the GARFIELD-AF registry. Methods GARFIELD-AF is an international registry of consecutively recruited patients aged ≥18 years with newly diagnosed AF and ≥1 stroke risk factor. Data were collected prospectively on 52,080 patients. Participants with missing or extreme BMI values and those without two-year follow-up were excluded. Cox proportional hazard models were used to estimate the effect of BMI on the risk of outcomes. Models were adjusted for age, sex, ethnicity, smoking, alcohol, and ≥moderate chronic kidney disease. Where appropriate participants were divided into groups based on BMI. Restricted cubic splines were used to assess non-linear relationships. Results BMI and outcome data were available for 40,495 patients. Those with higher BMI were generally younger, and more likely to have pre-existing hypertension, diabetes, or vascular disease (Table). Underweight patients received anticoagulation less often than those in other groups (60.3% vs 67.9%, respectively). During follow-up, 2,801 participants (6.9%) died and 603 (1.5%) had new/worsening heart failure. Following adjustment for potential confounders, a U-shaped relationship was seen between BMI and all-cause mortality and new/worsening heart failure (Figure). For all-cause mortality, the lowest risk was at 30kg/m2. Below this level, there was an 8% higher risk of mortality (95% confidence interval (CI) 6 to 9%) per 1kg/m2 lower BMI. Above 30kg/m2, there was a 5% higher risk of mortality per 1kg/m2 higher BMI (95% CI 4 to 7%). For new/worsening heart failure, the lowest risk was at 25kg/m2. Above this level, 1kg/m2 higher BMI was associated with an 5% higher risk (95% CI 13 to 6%). Conclusions BMI was an important risk factor for both all-cause mortality and new/worsening heart failure in AF. Those at both extremes of BMI are at higher risk. BMI and selected outcomes Funding Acknowledgement Type of funding source: Private company. Main funding source(s): The GARFIELD-AF registry is funded by an unrestricted research grant from Bayer AG.

A method for calculating BMI z-scores and percentiles above the 95th percentile of the CDC growth charts

Background The 2000 CDC growth charts are based on national data collected between 1963 and 1994 and include a set of selected percentiles between the 3rd and 97th and LMS parameters that can be used to obtain other percentiles and associated z-scores. Obesity is defined as a sex- and age-specific body mass index (BMI) at or above the 95th percentile. Extrapolating beyond the 97th percentile is not recommended and leads to compressed z-score values. Aim This study attempts to overcome this limitation by constructing a new method for calculating BMI distributions above the 95th percentile using an extended reference population. Subjects and methods Data from youth at or above the 95th percentile of BMI-for-age in national surveys between 1963 and 2016 were modelled as half-normal distributions. Scale parameters for these distributions were estimated at each sex-specific 6-month age-interval, from 24 to 239 months, and then smoothed as a function of age using regression procedures. Results The modelled distributions above the 95th percentile can be used to calculate percentiles and non-compressed z-scores for extreme BMI values among youth. Conclusion This method can be used, in conjunction with the current CDC BMI-for-age growth charts, to track extreme values of BMI among youth.

Relations of magnesium intake to cognitive impairment and dementia among participants in the Women’s Health Initiative Memory Study: a prospective cohort study

ObjectiveTo examine the associations of dietary and supplemental magnesium (Mg) as assessed by a semi-quantitative food frequency questionnaire with cognitive outcomes among ageing women.DesignThis work conducts a prospective cohort study...

Doenças e condições crônicas de saúde, multimorbidade e índice de massa corporal em idosos

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n5p509 The aim of this study was to analyze the association between diseases and chronic health conditions, multimorbidity and body mass index (BMI) in older adults from southern Brazil. Epidemiological cross-sectional study, with household basis was carried out with 343 older adults aged 60-79 years, selected by probability sampling and all aged 80 years or older (n=134). Hypertension, diabetes, cancer, chronic pulmonary diseases, coronary heart disease, cerebrovascular disease, arthritis, osteoporosis, depression, history of falls and dependency in activities of the daily living were assessed by self-report. Associations between independent variables and BMI (outcome) were tested using simple and multiple linear regression. Participated in the study 270 women (73.2±8.8 years) and 207 men (73.3±9.0 years). After adjustment (age, education, living arrangement, smoking, alcohol consumption, waist circumference, cognitive status and all other disease and chronic health conditions), the associations identified were: hypertension with higher BMI values (β 3.43; 95%CI: 2.38 to 4.48), for women, and chronic pulmonary disease with lower BMI values (β -2.05; 95%CI: -3.50 to -0.60). There was a linear trend between number of diseases and BMI for both sexes. Conclusion: The results showed an independent association between specific chronic diseases and BMI. Monitoring of nutritional status in older adults is important to identify extreme BMI values, especially those with more than two diseases and chronic health conditions.

Spatial pattern of body mass index among adults in the diabetes study of Northern California (DISTANCE).

BackgroundThe role that environmental factors, such as neighborhood socioeconomics, food, and physical environment, play in the risk of obesity and chronic diseases is not well quantified. Understanding how spatial distribution of disease risk factors overlap with that of environmental (contextual) characteristics may inform health interventions and policies aimed at reducing the environment risk factors. We evaluated the extent to which spatial clustering of extreme body mass index (BMI) values among a large sample of adults with diabetes was explained by individual characteristics and contextual factors.MethodsWe quantified spatial clustering of BMI among 15,854 adults with diabetes from the Diabetes Study of Northern California (DISTANCE) cohort using the Global and Local Moran’s I spatial statistic. As a null model, we assessed the amount of clustering when BMI values were randomly assigned. To evaluate predictors of spatial clustering, we estimated two linear models to estimate BMI residuals. First we included individual factors (demographic and socioeconomic characteristics). Then we added contextual factors (neighborhood deprivation, food environment) that may be associated with BMI. We assessed the amount of clustering that remained using BMI residuals.ResultsGlobal Moran’s I indicated significant clustering of extreme BMI values; however, after accounting for individual socioeconomic and demographic characteristics, there was no longer significant clustering. Twelve percent of the sample clustered in extreme high or low BMI clusters, whereas, only 2.67% of the sample was clustered when BMI values were randomly assigned. After accounting for individual characteristics, we found clustering of 3.8% while accounting for neighborhood characteristics resulted in 6.0% clustering of BMI. After additional adjustment of neighborhood characteristics, clustering was reduced to 3.4%, effectively accounting for spatial clustering of BMI.ConclusionsWe found substantial clustering of extreme high and low BMI values in Northern California among adults with diabetes. Individual characteristics explained somewhat more of clustering of the BMI values than did neighborhood characteristics. These findings, although cross-sectional, may suggest that selection into neighborhoods as the primary explanation of why individuals with extreme BMI values live close to one another. Further studies are needed to assess causes of extreme BMI clustering, and to identify any community level role to influence behavior change.Electronic supplementary materialThe online version of this article (doi:10.1186/1476-072X-13-48) contains supplementary material, which is available to authorized users.

Weight status and hypertension among adolescent girls in Argentina and Norway: Data from the ENNyS and HUNT studies

BackgroundTo provide data on overweight, obesity and hypertension among adolescent girls in Norway and Argentina.MethodsData was obtained from two population-based, cross-sectional and descriptive studies containing anthropometric and blood pressure measurements of 15 to 18 year old girls. The study included 2,156 adolescent girls from Norway evaluated between 1995 and 1997, and 669 from Argentina evaluated between 2004 and 2005.ResultsAround 15% of adolescent girls in Norway and 19% in Argentina are overweight or obese. Body mass index (BMI) distribution in these two countries is similar, with a low percentage (< 1%) of girls classified as thin. Norwegian adolescents show a height mean value 8 cm taller than the Argentinean. Obesity is strongly associated with systolic hypertension in both populations, with odds ratios of 11.4 [1.6; 82.0] and 28.3 [11.8; 67.7] in Argentina and Norway, respectively. No direct association between BMI and systolic hypertension was found, and only extreme BMI values (above 80th - 90th percentile) were associated with hypertension.ConclusionThis study confirms a current world health problem by showing the high prevalence of obesity in adolescents and its association with hypertension in two different countries (one developed and one in transition).

Perioperative Safety in the Longitudinal Assessment of Bariatric Surgery

To improve decision making in the treatment of extreme obesity, the risks of bariatric surgical procedures require further characterization. We performed a prospective, multicenter, observational study of 30-day outcomes in consecutive patients undergoing bariatric surgical procedures at 10 clinical sites in the United States from 2005 through 2007. A composite end point of 30-day major adverse outcomes (including death; venous thromboembolism; percutaneous, endoscopic, or operative reintervention; and failure to be discharged from the hospital) was evaluated among patients undergoing first-time bariatric surgery. There were 4776 patients who had a first-time bariatric procedure (mean age, 44.5 years; 21.1% men; 10.9% nonwhite; median body-mass index [the weight in kilograms divided by the square of the height in meters], 46.5). More than half had at least two coexisting conditions. A Roux-en-Y gastric bypass was performed in 3412 patients (with 87.2% of the procedures performed laparoscopically), and laparoscopic adjustable gastric banding was performed in 1198 patients; 166 patients underwent other procedures and were not included in the analysis. The 30-day rate of death among patients who underwent a Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding was 0.3%; a total of 4.3% of patients had at least one major adverse outcome. A history of deep-vein thrombosis or pulmonary embolus, a diagnosis of obstructive sleep apnea, and impaired functional status were each independently associated with an increased risk of the composite end point. Extreme values of body-mass index were significantly associated with an increased risk of the composite end point, whereas age, sex, race, ethnic group, and other coexisting conditions were not. The overall risk of death and other adverse outcomes after bariatric surgery was low and varied considerably according to patient characteristics. In helping patients make appropriate choices, short-term safety should be considered in conjunction with both the long-term effects of bariatric surgery and the risks associated with being extremely obese. (ClinicalTrials.gov number, NCT00433810.)

Spontaneous Pneumomediastinum May Be Associated with Both Anorexia Nervosa and Obesity

We read with great interest the article by Mondello et al. about spontaneous pneumomediastinum (SPM) which was recently published in Lung [1]. In their study, the authors presented their experience with 18 patients with SPM and discussed their symptomatology, diagnosis, treatment, and follow-up. An interesting finding in this review was that the majority of patients (10 of 18, 55%) were overweight or even obese. As the authors state, this was the first description of a possible association between obesity and SPM. In our opinion, this is a very intriguing association because SPM has also been associated with anorexia nervosa (AN) [2, 3]. In 1997, our group presented the case of a young woman with AN who also had SPM and diffuse soft tissue emphysema [2]. SPM is a rare but well-described complication in AN patients. To our knowledge there are only 21 such cases [3]. In these cases, Body mass index (BMI) ranged from 10.8 to 15 kg/m. Purging behavior such as self-induced vomiting is a prominent symptom in AN patients and may lead to SPM. However, vomiting was the precipitating factor [3] in only three of the 21 AN patients with SPM. The rest did not have a history of vomiting. Thus, it seems that SPM in AN patients has a different pathogenesis. Indeed, there are increasing data showing that malnutrition leads to atrophic changes in connective tissue, such as hypoplasia, thin alveolar walls, large alveoli, reduction or absence of building fat, and gelatinous transformation [4, 5]. Thus, it is believed that even a minimal increase of intra-alveolar pressure, which may occur during common daily activities, can be the cause of repeated air leaks through thin and atrophic alveolar walls in AN patients [2]. Interestingly, Mondello et al. found that the majority of SPM patients were overweight or even obese. Unfortunately, Mondello et al. did not provide data about BMI in these patients. However, it seems possible that SPM could be associated with extreme values of BMI—either extremely low or extremely high, which is the case in obesity and anorexia nervosa, respectively. At present, there are no data on the pathogenesis of SPM in obese people. We believe that more studies are necessary to investigate if obesity and anorexia nervosa share common pathophysiologic features that lead to spontaneous pneumomediastinum.

Effects of selective return on estimates of heritability for body mass index in the national heart, lung, and blood institute twin study

In the National Heart, Lung, and Blood Institute Twin Study, body mass index (BMI) was studied at military induction and at three subsequent examinations spanning five decades in a cohort of white, male World War II veterans. At military induction (1940s) and again at the first clinical examination of this study (1969-1973), there was close agreement of three commonly used estimates of heritability (range 0.72 to 0.80), and no evidence of a difference in total variance of BMI between the zygosities. However, at the last two examinations (1980s), the total variance in dizygotic (DZ) twins was significantly greater than that of monozygotic (MZ) twins (P less than 0.01) and these same heritability estimates varied widely. The among-pair estimate of heritability fell to unrealistic negative values, the within-pair estimate rose to values of 1.0 or greater, and the intraclass correlation coefficient estimate was slightly lower than in the entire cohort at baseline. The cause of the unequal zygosity total variance appears to have been nonparticipation at later examinations of MZ twins with extreme values of BMI, with no evidence of a similar selection process influencing DZ twins. This selection process biased the three estimates of heritability, making it difficult to determine which estimate is the most appropriate. Despite these biases, it remains clear that genetic factors contribute substantially to BMI in this population.