Between Body Mass Index Change Research Articles

The Relationship between Body Mass Index and Mental Health Among Iraq and Afghanistan Veterans

ABSTRACTBACKGROUNDObesity is a growing public health concern and is becoming an epidemic among veterans in the post-deployment period.OBJECTIVETo explore the relationship between body mass index (BMI) and posttraumatic stress disorder (PTSD) in a large cohort of Iraq and Afghanistan veterans, and to evaluate trajectories of change in BMI over 3 years.DESIGNRetrospective, longitudinal cohort analysis of veterans’ health recordsPARTICIPANTSA total of 496,722 veterans (59,790 female and 436,932 male veterans) whose height and weight were recorded at the Department of Veterans Affairs (VA) healthcare system at least once after the end of their last deployment and whose first post-deployment outpatient encounter at the VA was at least 1 year prior to the end of the study period (December 31, 2011).MAIN MEASURESBMI, mental health diagnoses.KEY RESULTSSeventy-five percent of Iraq and Afghanistan veterans were either overweight or obese at baseline. Four trajectories were observed: “stable overweight” represented the largest class; followed by “stable obese;” “overweight/obese gaining;” and “obese losing.” During the 3-year ascertainment period, those with PTSD and depression in particular were at the greatest risk of being either obese without weight loss or overweight or obese and continuing to gain weight. Adjustment for demographics and antipsychotic medication attenuated the relationship between BMI and certain mental health diagnoses. Although BMI trajectories were similar in men and women, some gender differences were observed. For example, the risk of being in the persistently obese class in men was highest for those with PTSD, whereas for women, the risk was highest among those with depression.CONCLUSIONSThe growing number of overweight or obese returning veterans is a concerning problem for clinicians who work with these patients. Successful intervention to reduce the prevalence of obesity will require integrated efforts from primary care and mental health to treat underlying mental health causes and assist with engagement in weight loss programs.Electronic supplementary materialThe online version of this article (doi:10.1007/s11606-013-2374-8) contains supplementary material, which is available to authorized users.

Body mass index, body mass change, and risk of oral cavity cancer: results of a large population-based case–control study, the ICARE study

The association between body mass index (BMI) and the risk of oral cavity cancer, suggested by the few available studies, is controversial because of weight loss preceding cancer diagnosis and possible confounding by tobacco and alcohol consumption. The aim of this study was to evaluate in France, a high-incidence country, the association between the risk of oral cavity cancer and body mass index at interview, 2 years before the interview and at age 30, as well as BMI change. We used data from a population-based case-control study, the Investigation of occupational and environmental CAuses of REspiratory cancers study, with personal interviews and standardized questionnaires including 689 cases of oral cavity squamous cell carcinoma and 3,481 controls. Odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated by unconditional logistic regression and were adjusted for gender, age, area of residence, education, tobacco smoking, and alcohol drinking. ORs were increased in underweight subjects at interview (OR 6.25, 95% CI 3.74-10.45). No association with underweight 2 years before the interview and at age 30 was found. Overweight and obesity at interview, 2 years before the interview and at age 30 were associated with decreased ORs (ranging from 0.13 to 0.60). BMI gain greater than 5% between age 30 and 2 years before the interview was inversely associated with oral cavity cancer (OR 0.42, 95% CI 0.33-0.54). These associations were stronger in men, and in smokers and drinkers. These results add further support to the existence of a reduced risk of oral cavity cancer among overweight and obese people or among people who increased their BMI in adulthood. The underlying mechanisms remain to be clarified.

Abstract MP61: Body Mass Index and Mortality among Adults with Incident Type Diabetes: Results from Two Prospective US Cohort Studies

Background: Recent evidence suggests that having normal weight at time of diagnosis of type 2 diabetes (T2D) is associated with an increased risk of premature death, compared to being overweight or obese; these studies were limited in their sample size and ability to adequately address residual confounding by smoking and reverse causation. Objective: To prospectively evaluate the association between body mass index (BMI) at T2D diagnosis and mortality in two large cohorts. Methods: Women and men with incident T2D from the Nurses’ Health Study (1978-2010; N=8,984) and Health Professionals Follow-up Study (1988-2010; N=2,443) were included if they were free of major chronic disease (cardiovascular disease [CVD], cancer) at T2D diagnosis. Participants’ self-reported body weight preceding diagnosis (mean 11 months) and height was used to calculate BMI (kg/m2). Cox proportional hazards models estimated the relative risk (HR) and 95% confidence interval (CI) for mortality across BMI categories. Multivariable models adjusted for age, smoking, baseline comorbidities (high blood pressure, cholesterol), and several other lifestyle factors. Fixed-effects meta-analyses were used to combine individual cohort estimates. Results: In all, 3,119 total deaths were observed over a follow-up of 36 years in women (18.7 deaths/1,000 person-years) and 26 years in men (25.2 deaths/1,000 person-years). A J-shaped association was observed across BMI categories (18.5-22.4, 22.5-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, >35.0) and all-cause mortality (HR [CI] by category: 1.26[1.03, 1.55], 1[reference], 1.11[0.97, 1.28], 1.08[0.94, 1.25], 1.19[1.04, 1.37], 1.33[1.15, 1.55]). After stratifying by smoking status, a direct linear association was present among never smokers and a J-shaped relationship persisted among ever smokers. Excluding deaths in the first 4 years of follow-up and adjusting for BMI change prior to diagnosis further accentuated the linear relationship between BMI and all-cause mortality among never smokers (0.90[0.57, 1.43], 1.00 [reference], 1.19[0.91, 1.57], 1.20[0.91, 1.58], 1.27[0.97, 1.65], 1.50[1.14, 1.99]; p-trend<0.001). The association across BMI categories and CVD mortality was also linear among never smokers, and flat among ever smokers. In addition, among ever smokers, cancer mortality was highest among those with BMI 18.5-22.5. No clear trend was observed between BMI and mortality due to other causes. Excluding insulin users did not appreciably modify the associations. Conclusions: We found no evidence to support lower mortality rates among diabetics who were overweight or obese at diagnosis, compared to their normal-weight counterparts. In contrast, after accounting for confounding by smoking, we observed direct linear relationships between BMI and both all-cause and CVD mortality in our cohorts. Reducing other biases strengthened these relationships.

BMI Change Patterns and Disability Development of Middle-aged Adults with Diabetes: A Dual Trajectory Modeling Approach

Few longitudinal studies have examined associations between body mass index (BMI) changes in adults with diabetes and the development of disability. To investigate association patterns between BMI and disability in middle-aged adults with diabetes. Retrospective cohort design with data from the 1992-2006 Health and Retirement Study (HRS). A group-based joint trajectory method identified distinct BMI change trajectories and their link to subsequent disability trajectories. U.S. nationally representative adults aged 51-61 who reported a diagnosis of diabetes in the 1992 HRS (N = 1,064). BMI and self-reported disability score were the main variables. Sociodemographic, clinical, behavioral, and diabetes-related factors were also examined. Four distinct weight trajectories (stable normal weight, 28.7%; stable overweight, 46.2%; loss and regain obese, 18.0%; weight cumulating morbidly obese, 7.1%) and three disability trajectories (little or low increase, 34.4%; moderate increase, 45.4%; chronic high increase, 20.2%) best characterized the long-term patterns of BMI and disability change in middle-aged adults with diabetes. Adults in stable normal weight had the highest probability of being in the little/low increase disability group; however, one in five adults in that group progressed into chronic high disability, a higher proportion compared to the stable overweight group. Although there were various ways in which the two trajectories were linked, the beneficial impacts of optimizing weight in adults with diabetes were supported. In addition, the complexity of diabetes control in those with relatively normal weight was highlighted from this study.

Low Body Mass Index Is Associated with a Positive Response during a Head‐Up Tilt Test

To describe the association between body mass index (BMI) and a positive response during a head-up tilt test (HUT) in patients referred for an investigation of syncope. Observational study of patients referred for the diagnostic evaluation of syncope. Patients were divided into four groups according to their BMI: <18.5 kg/m(2), 18.5-24.9 kg/m(2), 25-29.9 kg/m(2), and > 30 kg/m(2). A total of 419 patients were evaluated. The mean age was 43 ± 22 years, and 62% were female. The prevalence of a positive tilt test was different between groups when stratified by BMI (P = 0.01), with a higher proportion of patients with positive tests among those with BMI <18.5 kg/m(2) compared with other groups (P = 0.05). Multivariate analysis also showed that underweight patients had a 3.9 times higher risk for a positive HUT response (P = 0.01); additionally, the use of contraceptive drugs was associated with a protective effect during HUT (odds ratio: 0.35, confidence interval: 0.19-0.45, P = 0.001). In our sample, changes in BMI are associated with a positive response for HUT, and oral contraceptives seemed to protect against this response. Further studies are needed with larger numbers of patients to corroborate this finding.

Cross-sectional and longitudinal association of body mass index and brain volume

Although a link between body mass index (BMI) and brain volume has been established in several cross-sectional studies, evidence of the association between change in BMI over time and changes in brain structure is limited. Using data from a cohort of 347 former lead workers and community controls with two magnetic resonance imaging scans over a period of ~5 years, we estimated cross-sectional and longitudinal associations of BMI and brain volume using both region of interest (ROI) and voxel-based morphometric (VBM) methods. We found that associations of BMI and brain volume were not significantly different in former lead workers when compared with community controls. In the cross-sectional analysis, higher BMIs were associated with smaller brain volumes in gray matter (GM) using both ROI and VBM approaches. No associations with white matter (WM) were observed. In the longitudinal analysis, higher baseline BMI was associated with greater decline in temporal and occipital GM ROI volumes. Change in BMI over the 5-year period was only associated with change in hippocampal volume and was not associated with change in any of the GM ROIs. Overall, higher BMI was associated with lower GM volume in several ROIs and with declines in volume in temporal and occipital GM over time. These results suggest that sustained high body mass may contribute to progressive temporal and occipital atrophy.

The Effect of Body Mass Index and Weight Change on Epithelial Ovarian Cancer Survival in Younger Women: A Long-Term Follow-Up Study

The objective of this study was to assess the relationship between body mass index (BMI) and epithelial ovarian cancer survival among young women. We conducted a cohort analysis of 425 women aged 20-54 years with incident epithelial ovarian cancer enrolled during 1980-1982 in Cancer and Steroid Hormone (CASH), a population-based, case-control study. Participants' vital status was ascertained though linkage with the Surveillance, Epidemiology and End Results (SEER) program. Using Cox proportional hazards models, we estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association between survival and usual adult BMI, BMI at age 18, and weight change from age 18 to adult. During a follow-up of up to 17 years, 215 women died. Compared to women with an adult BMI in the lowest quartile (<20.7), women in the second (20.8-22.5), third (22.6-24.9), and fourth (≥25.0) quartiles were not at increased risk for death (HR 1.2, 95% CI 0.8-1.8; HR 1.1, 95% CI 0.7-1.6; and HR 0.9, 95% CI 0.6-1.4, respectively) (p trend=0.6). Similarly, neither age 18 BMI nor weight change were associated with ovarian cancer survival. Although elevated BMI is associated with increased ovarian cancer risk among young women, we found no evidence of its association with ovarian cancer survival in this population.

BMI, long-term changes in BMI, and risk of cancer mortality in a large cohort study.

1502 Background: There are indications of an association between Body Mass Index (BMI) and risk of different cancer types. There is dispute whether this association differs between males and females. Methods: We studied the association of BMI at the first survey with risk of mortality from the most common types of cancer (lung, colorectal, breast and prostate cancer) in a large general population-based cohort study (Vlagtwedde-Vlaardingen, 1965-1990) with follow-up on mortality status until 2009. Additionally, we assessed this association based on tertiles of the annual change in BMI (defined as the difference between BMI at last survey and first survey divided by the time between last and first survey). We used 3 categories of BMI (&lt; 25 kg/m2, 25-30 kg/m2, and ≥ 30 kg/m2) and changes in BMI (&lt; 0.02 kg/m2/yr, 0.02-0.2 kg/m2/yr, and &gt; 0.2 kg/m2/yr) in the analyses. The multivariate Cox regression model was adjusted for age, smoking, gender. Analyses were additionally stratified by gender and smoking. Results: Among all 8645 subjects, 1194 died due to cancer (lung cancer: 275; colorectal cancer: 134; breast cancer: 117; prostate cancer: 83). Mortality from all types of cancer was significantly increased in subjects with BMI &gt; 30 kg/m2 (HR (95 % CI)) = 1.22 (1.00-1.48)), especially in females (1.38 (1.06-1.81)) and in never smokers (1.39 (1.02-1.90)). Prostate cancer mortality was significantly increased in males with BMI 25-30 kg/m2 (2.04 (1.90-3.83)) and &gt; 30 kg/m2 (2.61 (1.02-6.67)). This association between prostate cancer mortality and BMI was higher in smokers. Lung cancer mortality risk was decreased in subjects with BMI 25-30 kg/m2 (0.71 (0.54-0.93)) and &gt; 30 kg/m2 (0.82 (0.50-1.32)), especially in males, in smokers, and in smoking males. There were no significant associations between BMI and colorectal or breast cancer mortality nor between change in BMI and mortality from all analyzed types of cancer. Conclusions: We show that an increase in BMI is associated with an increased risk of mortality from all types of cancer in females and with an increased mortality risk from prostate cancer in males but with a decreased lung cancer mortality risk, especially in males. More research is needed into the biological mechanisms that link BMI to cancer.

Body mass index and short-term weight change in relation to treatment outcomes in women undergoing assisted reproduction

To assess the relation between body mass index (BMI) and short-term weight change with assisted reproductive technology (ART) outcomes. Prospective cohort study. Fertility center. A total of 170 women undergoing 233 ART cycles. Baseline BMI and short-term weight change were related to ART outcomes. Regression models accounting for repeated observations were used to adjust data for potential confounders. Peak E2 levels, oocyte yield, MII yield, fertilization rate, embryo quality, postive [beta]-hCH, clinical pregnancy and live birth rates. Overweight and obesity were associated with lower live birth rates. The adjusted live birth rate (95% confidence interval) was 42% (28%-58%) among women with a BMI between 20 and 22.4 kg/m(2) and 23% (14%-36%) among overweight or obese women. Short-term weight loss was associated with a higher proportion of metaphase II (MII) oocytes retrieved. The adjusted proportion of MII eggs was 91% (87%-94%) for women who lost 3 kg or more and 86% (81%-89%) for women whose weight remained stable. This association was stronger among women who were overweight or obese at baseline. Short-term weight loss was unrelated to positive β-hCG, clinical pregnancy, or live birth rates. Overweight and obesity were related to lower live birth rates in women undergoing ART. Short-term weight loss was related to higher MII yield, particularly among overweight and obese women, but unrelated to clinical outcomes.

Weight status and disability in multiple sclerosis: An examination of bi-directional associations over a 24-month period

BackgroundNatural history studies have typically focused on non-modifiable factors as predictors of disability progression in multiple sclerosis (MS). Weight status has emerged as a correlate of disability status in cross-sectional studies of persons with MS and represents a possible modifiable predictor of disability progression over time. ObjectiveThis study examined the prospective, bi-directional associations between body mass index (BMI) and disability over a 24-month time course in persons with MS who have mild-to-moderate disability. MethodsThe sample included 269 individuals with relapsing-remitting MS (RRMS) that were part of an ongoing, longitudinal investigation of symptoms and physical activity in persons with RRMS. BMI and PDDS were determined by self-report questionnaires distributed and collected through the U.S. postal service. Data were collected from participants on three occasions: baseline, 12 months, and 24 months. ResultsMean BMI at baseline was 27.2 (7.0)kg/m2 and over 50% of participants were classified as overweight (BMI=25.0–29.9kg/m2) or obese (BMI≥30.0kg/m2). There was a significant increase in PDDS over the study period (p<0.0001), but no change in BMI (p=0.41). There were no significant correlations between BMI and PDDS for any of the three time points (p>0.05). Path analysis indicated a minimal and inconsistent impact of BMI on the change in PDDS over time, and PDDS had a minimal and inconsistent influence on change in BMI. ConclusionsOver a 24-month time course, we demonstrated an increase in disability, but minimal evidence that this change was predicted by BMI in persons with mild-to-moderate MS. Even though BMI was not predictive of disability, the prevalence of overweight and obesity was considerable and should be the focus of subsequent intervention in MS.

Association Between Body Mass Index and Health-Related Quality of Life Among an Australian Sample

Objective This study investigated the association between body mass index (BMI) and changes in BMI over time with health-related quality-of-life data among a general and representative sample of the Australian population. Methods The sample consisted of respondents between the ages of 18 and 79 who completed the Household, Income and Labour Dynamics in Australia (HILDA) Survey in 2007 and 2009. These respondents completed the SF-36 questionnaire and provided data on their height, weight, medical conditions, and sociodemographic characteristics. SF-36 questionnaire responses were converted into health state utility values using the SF-6D algorithm. Regression analysis was used to examine the relationship between BMI and utility, controlling for a range of obesity-related medical conditions and sociodemographic characteristics. Results Obese men (BMI value ≥30) had, on average, a lower utility score (–0.0190, P < 0.001) than men within an “acceptable” BMI range (BMI 18.5 to <25). Obese women (BMI value ≥30) also had, on average, a lower utility score (–0.0338, P < 0.001) than women within an acceptable BMI range (18.5 to <25). Although BMI was not associated longitudinally with utility, there was a statistically significant negative longitudinal relationship between arthritis (–0.0153, P < 0.01) and depression/anxiety disorders (–0.0358, P < 0.001) and utility. Conclusions Cross-sectional results suggest that BMI is negatively associated with utility and that further investigation of the longitudinal relationship between BMI and utility is warranted.

Obesity and asthma: An association modified by age of asthma onset

Studies of asthma phenotypes have identified obesity as a component of a group characterized by a high proportion of subjects with adult-onset asthma. However, whether age of asthma onset modifies the association between obesity and asthma is unknown. We sought to compare the associations between body mass index (BMI) categories with physiological, inflammatory, and clinical parameters across age of asthma onset phenotypes; and to compare the rate of BMI change in relation to asthma duration, by age of onset asthma phenotypes. From the Severe Asthma Research Program, we defined age of asthma onset as early (<12 years of age) and late (≥12 years of age). Comparisons of BMI categories were done within age-of-onset groups, and obesity was also compared across these groups. Multivariable logistic regression analysis was done to evaluate the association between BMI categories with health care use and respiratory symptoms and multivariable linear regression for the association between duration of asthma and weight gain (BMI change per year). An interaction between obesity and age of asthma onset was included in the multivariable analyses. The study population consisted of 1049 subjects, and the median age for asthma onset was 10 years (interquartile range, 4-25 years); 48% had late-onset asthma (≥12 years of age), and 52% had early-onset asthma (<12 years of age). Compared with obese subjects with late-onset asthma, obese subjects with early-onset asthma had more airway obstruction, bronchial hyperresponsiveness, and higher odds ratios of ever having 3 or more previous oral steroid tapers per year or intensive care unit admissions for asthma per preceding year (interactions between obesity and age of asthma onset were P= .055 and P= .02, respectively). In subjects with early-onset asthma but not in subjects with late-onset asthma, there was a significant association between increasing BMI and duration of asthma after adjusting for confounders. The interaction between asthma duration and age of asthma onset was a P value of less than .01. Asthmatic subjects are differentially affected by obesity based on whether they had asthma early (<12 years of age) or later in life. These results highlight the need to understand obesity as a comorbidity that affects specific clinical phenotypes and not all asthma subjects alike.

The association between change in body mass index and upper aerodigestive tract cancers in the ARCAGE project: Multicenter case–control study

Previous studies reported an inverse relationship between body mass index (BMI) and upper aerodigestive tract (UADT) cancers. Examining change in BMI over time may clarify these previous observations. We used data from 2,048 cases and 2,173 hospital- and population-based controls from ten European countries (alcohol-related cancers and genetic susceptibility in Europe study) to investigate the relationship with BMI and adult change in BMI on UADT cancer risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for associations between BMI at three time intervals and BMI change on UADT cancer development, adjusting for center, age, sex, education, fruit and vegetable intake, smoking and alcohol consumption. We found an inverse relationship between UADT cancers and BMI at time of interview and 2 years before interview. No association was found with BMI at 30 years of age. Regarding BMI change between age 30 and 2 years before interview, BMI decrease (BMI change <-5%) vs. BMI stability (-5% ≤ BMI change <5%) showed no overall association with UADT cancers (OR = 1.15; 95% CI = 0.89, 1.49). An increase in BMI (BMI change ≥+5%) was inversely associated with UADT cancers (OR = 0.74; 95% CI = 0.62, 0.89). BMI gain remained inversely associated across all subsites except for esophageal cancer. When stratified by smoking or by drinking, association with BMI gain was detected only in drinkers and smokers. In conclusion, BMI gain is inversely associated with UADT cancers. These findings may be influenced by smoking and/or drinking behaviors and/or the development of preclinical UADT cancers and should be corroborated in studies of a prospective nature.

Splitting the Differences

Splitting the Differences

C-reactive protein levels and body mass index: elucidating direction of causation through reciprocal Mendelian randomization.

ContextThe assignment of direction and causality within networks of observational associations is problematic outside randomized control trials and the presence of causal a relationship between body mass index (BMI) and C-reactive protein (CRP) is disputed.ObjectiveUsing reciprocal Mendelian randomization, we aim to assess the direction of causality in relationships between BMI and CRP and to demonstrate this as a promising analytical technique.Participants and methodsThe Study was based in a large, cross-sectional European study from Copenhagen, Denmark. Genetic associates of BMI (FTOrs9939609) and circulating CRP (CRPrs3091244) have been used to re-examine observational associations between them.ResultsObservational analyses showed strong, positive association between circulating CRP and BMI (change in BMI for a doubling in logCRP of 1.03kg/m2 (95%CI 1.00, 1.07), p<0.0001). Analysis using CRPrs3091244 to re-estimate the causal effect of circulating CRP on BMI yielded null effects (change in BMI for a doubling in logCRP of −0.24kg/m2 (95%CI −0.58, 0.11), p=0.2). In contrast, analysis using FTOrs9939609 to assess the causal effect of BMI on circulating CRP confirmed observational associations (ratio of geometric means of CRP per standard deviation increase in BMI 1.41(95%CI 1.10, 1.80), p=0.006).ConclusionsTogether, these data suggest that the observed association between circulating CRP and measured BMI is likely to be driven by BMI, with CRP being a marker of elevated adiposity. More generally, the method of reciprocal randomization has general applicability in determining direction of causation within inter-correlated networks of metabolic components and methods such as this provide an approach for delivering immediate and clinically applicable information.

Relationship between changes of body mass index and cognitive decline in Parkinson's disease

Although the relation between body mass index (BMI) changes and risk of dementia is not always associated linearly, decreased BMI has been reported that it may be associated with increased risk of cognitive decline in the elderly. Weight loss is very common in patients with Parkinson's disease (PD) because of changes in appetite due to medication or chewing and swallowing difficulty related with muscular rigidity or higher energy expenditure due to involuntary movement. However, studies comparing BMI changes with cognitive function in PD have not been done yet. We performed this study to evaluate association between BMI changes and rate of cognitive decline and to know whether co-morbid conditions occur more frequently in BMI reduction group of PD. PD patients who measured their height and weight to calculate BMI and evaluated cognitive function regularly at the movement clinic of CNUH were recruited retrospectively. The patients (n = 78) were divided into two groups according to BMI changes during initial 6 months: decreased vs. stable BMI groups. Cognitive functions were evaluated by the Korean versions of Mini-Mental State Examination (MMSE) and the modified Mini-Mental State (3MS) test. Clinical examination, MMSE and 3MS were done at 6-, 12-, 24- and 36-month of follow-up. The rate of cognitive decline (MMSE and 3MS score changes/months) was compared in both groups from the baseline to each follow up. The co-morbid conditions such as pneumonia or bone fracture were evaluated through detailed chart review. The decreased BMI group showed more rapid decline of cognitive function than that of stable BMI group in PD. The rate of cognitive decline measured by both MMSE and 3MS tests was significantly faster especially at the 24- and 36- month of the follow-ups compared with the initial 1-year period of the follow-up in the decreased BMI group. No significant difference in the frequency of co-morbid diseases was found between the two groups. This study suggests that decreased BMI might be a useful indicator for future risk of dementia and let clinicians predict faster rate of cognitive decline in patients with PD.

BMI change is associated with fracture incidence, but only in non-smokers. The Tromsø Study

Few studies have examined the association between body mass index (BMI) change and fracture in a general population. We observed that BMI loss was associated with increased fracture risk in non-smoking men and women, but not in smokers. BMI gain was associated with decreased fracture risk in women. Weight loss has been associated with increased fracture risk, but few studies have included men. The aim of this study was to examine the association between BMI change and fracture risk in both genders. A population-based cohort study in Tromsø, Norway, of adults, aged 20 to 54 years in 1979, who participated in two or three health surveys in 1979-1980, 1986-1987, and 1994-1995. Weight and height were measured at each survey. Information about lifestyle was obtained by questionnaires. Poisson regression was used to estimate incidence rates and Cox proportional hazards regression model to assess the association between fracture risk and BMI change. Fractional polynomials were used to accommodate non-linear associations. A total of 5,549 men and 5,428 women participated. There were 1,135 fractures during 10 years of follow-up. Reduction in BMI was associated with increased non-vertebral fracture risk in non-smokers, but not in smokers. The hazard ratio in male and female non-smokers per 10-year BMI decrease of 2 kg/m(2) versus a BMI increase of 1 kg/m(2) was 1.79 (95% confidence interval (CI), 1.17-2.75) and 1.60 (95% CI, 1.28-1.99), respectively. The association was not significantly modified by initial BMI or age or by exclusion of subjects with cardiovascular diseases, diabetes, or cancer. In female non-smokers, weight gain was inversely associated with fracture risk. In a general Norwegian population, reduction in BMI was significantly associated with increased fracture risk in male and female non-smokers, but not in smokers. These findings could not be explained by preexisting disease.

INFLAMMATORY MARKER IN PREHYPERTENSION ARE ASSOCIATED WITH BODY MASS BUT NOT WITH BLOOD PRESSURE TRENDS: HT.2.01

Previous studies reported an increase of white blood cell (WBC) count in hypertension, prehypertension and metabolic syndrome. In this paper we examine WBC trends in the randomized prospective placebo controlled TROPHY trial of prehypertension. Baseline and 2 years follow up data were available in 761 subjects. At baseline there was a significant correlation between body mass index (BMI) and WBC, neutrophiles (NEU) and lymphocytes (LY); p < 0.0001, p < 0.0003, p < 0.0002 respectively. Baseline levels of triglycerides (TG) also correlated strongly with WB, NUE, and LY. Despite a wide range of home blood pressure (HBP) values the HBP did not correlate with baseline hematology. Treatment with candesartan substantially decreased the HBP (-5.8/2.5 mmHg corrected for the placebo effect) but after two years of observation WBC, NEU and LY count s were similar in placebo and actively treated groups. Changes from baseline to 24 months in BMI correlated strongly with hematological changes; WBC (p < .0001), NEU (p = 0003 and LY (p = .003). BP changes correlated only with NEU changes (p < .005) and that observation may reflect the strong correlation between BP and BMI changes. Conclusion: In the TROPHY trial BP lowering with candesartan suppressed new onset hypertension but two years of antihypertensive treatment failed to affect WBC trends. The association of baseline and in-trial BMI with hematological inflammatory markers suggests that life style modification must be an integral part in the management of prehypertension.

Cross-sectional and longitudinal relation between serum 25-hydroxyvitamin D and body mass index: the Tromsø study

The serum 25-hydroxyvitamin D (25(OH)D) levels are lower in obese than lean subjects. The present study examines the cross-sectional and longitudinal relations between body mass index (BMI) and serum 25(OH)D, and the serum 25(OH)D response to vitamin D supplementation in relation to BMI. The Tromsø study is a longitudinal population-based multipurpose study. The fourth survey was conducted in 1994 and the sixth in 2008. The intervention study was a 1-year placebo-controlled randomized intervention trial, where the results from the 93 subjects given 40,000IU per week are presented. A total of 10,229 subjects were included in the 2008 cross-sectional study. There was a significant negative association between serum 25(OH)D levels and BMI which was also present during the winter months. Serum 25(OH)D levels varied through seasons, but not BMI. In the longitudinal study from 1994 to 2008 which included 2,656 subjects, change in BMI was a significant negative predictor of change in 25(OH)D. In the intervention study, there was a significant and negative correlation between BMI and serum 25(OH)D both at baseline and at the end of the study. The increase in serum 25(OH)D after 1year was significantly and inversely related to baseline BMI. We have confirmed the strong association between serum 25(OH)D and BMI. The very obese need higher vitamin D doses than lean subjects to achieve the same serum 25(OH)D levels.

Does an increase in body mass index over 10 years affect knee structure in a population-based cohort study of adult women?

IntroductionAlthough obesity is a modifiable risk factor for knee osteoarthritis (OA), the effect of weight gain on knee structure in young and healthy adults has not been examined. The aim of this study was to examine the relationship between body mass index (BMI), and change in BMI over the preceding 10-year period, and knee structure (cartilage defects, cartilage volume and bone marrow lesions (BMLs)) in a population-based sample of young to middle-aged females.MethodsOne hundred and forty-two healthy, asymptomatic females (range 30 to 49 years) in the Barwon region of Australia, underwent magnetic resonance imaging (MRI) during 2006 to 2008. BMI measured 10 years prior (1994 to 1997), current BMI and change in BMI (accounting for baseline BMI) over this period, was assessed for an association with cartilage defects and volume, and BMLs.ResultsAfter adjusting for age and tibial plateau area, the risk of BMLs was associated with every increase in one-unit of baseline BMI (OR 1.14 (95% CI 1.03 to 1.26) P = 0.009), current BMI (OR 1.13 (95% CI 1.04 to 1.23) P = 0.005), and per one unit increase in BMI (OR 1.14 (95% CI 1.03 to 1.26) P = 0.01). There was a trend for a one-unit increase in current BMI to be associated with increased risk of cartilage defects (OR 1.06 (95% CI 1.00 to 1.13) P = 0.05), and a suggestion that a one-unit increase in BMI over 10 years may be associated with reduced cartilage volume (-17.8 ml (95% CI -39.4 to 3.9] P = 0.10). Results remained similar after excluding those with osteophytes.ConclusionsThis study provides longitudinal evidence for the importance of avoiding weight gain in women during early to middle adulthood as this is associated with increased risk of BMLs, and trend toward increased tibiofemoral cartilage defects. These changes have been shown to precede increased cartilage loss. Longitudinal studies will show whether avoiding weight gain in early adulthood may play an important role in diminishing the risk of knee OA.