Long-term body weight variability is associated with elevated C-reactive protein independent of current body mass index among Japanese men

Association of body mass index and blood pressure variability with 10-year mortality and renal disease progression in type 2 diabetes

BACKGROUND

Variability in biological parameters may be associated with adverse outcomes. The aim of the study was to determine whether variability in body mass index (BMI) and blood pressure is associated with all-cause, cardiovascular mortality and cancer mortality or with renal disease progression in subjects with type 2 diabetes.

METHODS

The diabetes database was accessed, and all the information on patient visits (consultations) carried out in the study period (1 January 2008-31 December 2019) was extracted and linked to the laboratory database and the mortality register.

RESULTS

The total number of patients included in the study population was 26,261, of whom 54.4% were male. Median (interquartile range, IQR) age was 60.2 (51.8-68.3) years. The coefficient of variability of BMI was independently associated with increased all-cause and cardiovascular, but not cancer, mortality. Glycated haemoglobin (HbA1c) was associated with increased all-cause, cardiovascular, and cancer mortality as well as with renal progression. Variability in systolic blood pressure, diastolic blood pressure, and pulse pressure was associated with increased all-cause and cardiovascular mortality in bivariate, but not in multivariate, analyses.

CONCLUSIONS

Variability in BMI was associated with increased all-cause and cardiovascular, but not cancer, mortality in a large real-world contemporary population. Our results also confirm the association of HbA1c with increased all-cause, cardiovascular, and cancer mortality as well as with renal progression.

The association of body mass index variability with cardiovascular disease and mortality: a mediation analysis of pooled cohorts

AIM

We aimed to investigate the effect of BMI variability on CVD and mortality and to explore the mediation effects of the main cardiovascular risk factors contributing to this association.

METHOD

Participants aged 40-65 years were pooled from three cohort studies(ARIC [Atherosclerosis Risk in Communities], MESA [Multi-ethnic Study of Atherosclerosis], and TLGS [Tehran Lipid and Glucose Study]. We employed root mean squared error of the fractional mixed model to calculate BMI variability in the measurement period. In the event assessment period, the hazard ratios for CVD and mortality were estimated using Cox proportional hazard regression models. In the next step, the mediation and interaction effects of fasting plasma glucose, total cholesterol, and systolic blood pressure were determined.

RESULTS

A total of 19073 participants were included in this pooled analysis. During a median of 20.7 years of follow-up, 3900 (20.44%) CVD and 6480 (33.97%) all-cause mortality events were recorded. After adjusting for potential confounders, BMI variability was linked to the 1.3 (1.2-1.4) and 1.7 (1.6-1.8) increased risk of CVD and mortality, respectively. Fasting plasma glucose mediated approximately 24% and 8% of the effect of BMI variability on CVD and mortality, respectively. However, systolic blood pressure and total cholesterol did not have mediation effects in this association.

CONCLUSION

High BMI variability is independently associated with the development of CVD and mortality. This association is partly mediated through fasting plasma glucose. Modern cardiometabolic therapies that lower fasting glucose may reduce the risk of future CVD and mortality in individuals with high BMI variability.

Gender differences in midlife to later-life cumulative burden and variability of obesity measures and risk of all-cause and cause-specific mortality

BACKGROUND/OBJECTIVES

Previous studies have reported the gender-specific association between general and central obesity measures, using snapshot assessments, and mortality events. This study seeks to further explore this link by examining how the longitudinal cumulative burden and variability of obesity measures from midlife to later-life impact mortality events in the Atherosclerosis Risk in Communities (ARIC) study population, specifically in relation to gender differences.

SUBJECTS/METHODS

Using data from the ARIC study, a total of 7615 (4360 women) participants free of cardiovascular disease, cancer, and early mortality events were included in the data analysis. Longitudinal cumulative burden (estimated by the area under the curve (AUC) using a quadratic mixed-effects method) and variability (calculated according to average successive variability (ASV)) were considered as exposures, separately and all together. Cox proportional hazard regression models were used to estimate multivariable-adjusted standardized hazard ratios.

RESULTS

The mean age was 62.4 and the median follow-up was 16.9 years. In men, AUCs of waist-related obesity measures, and also ASVs of all obesity measures were associated with increased all-cause mortality risk. In women, waist circumference and waist-to-height ratio AUCs were associated with increased all-cause mortality risk. Regarding cardiovascular mortality, all adiposity measures ASVs in both genders and waist-related obesity measures AUCs in men were associated with increased risk. Significant gender differences were found for the associations between cumulative and variability of waist-to-hip ratio for all-cause mortality and all adiposity measures ASVs for cardiovascular mortality risk with higher impact among men.

CONCLUSIONS

Cumulative burden and variability in general and central obesity measures were associated with higher all-cause and cardiovascular mortalities among men. In women, general obesity measures variability, as well as cumulative and variability of central adiposity measure, increased all-cause mortality risk.

Weight fluctuation, mortality, and cardiovascular disease in adults in 18 years of follow-up: Tehran Lipid and Glucose Study

PURPOSE

Controversies exist in the effect of body weight loss and fluctuation on cardiovascular disease (CVD) and mortality. This study aims to assess the effect of weight variability on CVD and all-cause and cardiovascular mortality in the Tehran Lipid and Glucose Study (TLGS) cohort.

METHOD

Participants aged  ≥ 40 year at the baseline period with at least 3 BMI measurements were included in this study. After excluding individuals with cancer, CVD, end-stage renal disease, systemic use of glucocorticoids, pregnancy, and missing covariates at the baseline, a total of 3461 participants were enrolled and followed for 18 years. BMI variability was defined using root mean squared error (RMSE) and average successive variability (ASV). In the RMSE method, BMI variability was calculated using the best-fitting model for BMI trend of each subject. Multivariate Cox proportional hazard models were applied to assess BMI variability's effect on CVD and mortality.

RESULTS

Among the 3461 participants in this study, the group with the highest weight variability had an increased risk of death for all-cause (HR 1.65; 95% CI 1.21-2.25), non-cardiovascular (HR 1.77; 95% CI 1.24-2.53), and non-cancer (HR 1.77; 95% CI 1.25-2.50) mortality. However, BMI variability showed to be protective against CVD (HR 0.76; 95% CI 0.6-0.97). These findings were significant in males, non-smokers, participants with age  ≤ 60 year, BMI < 30, negative BMI slope, and both diabetic and non-diabetic subjects.

CONCLUSION

High BMI variability is associated with increased risk of all-cause, non-CVD, and non-cancer mortality, although protective for the CVD event. Appropriate strategies for body weight maintenance after weight loss could be adopted to avoid weight variability, particularly in non-obese subjects.

Recent Updates on Associations among Various Obesity Metrics and Cognitive Impairment: from Body Mass Index to Sarcopenic Obesity

Obesity and obesity-associated morbidity continues to be a major public health issue worldwide. Dementia is also a major health concern in aging societies and its prevalence has increased rapidly. Many epidemiologic studies have shown an association between obesity and cognitive impairment, but this relationship is not as well established as other comorbidities. Conflicting results related to the age and sex of participants, and the methodology used to define obesity and dementia may account for the uncertainty in whether obesity is a modifiable risk factor for dementia. More recently, sarcopenia and sarcopenic obesity have been reported to be associated with cognitive impairment. In addition, new mediators such as the muscle-myokine-brain axis and gut-microbiota-brain axis have been suggested and are attracting interest. In this review, we summarize recent evidence on the link between obesity and cognitive impairment, especially dementia. In particular, we focus on various metrics of obesity, from body mass index to sarcopenia and sarcopenic obesity.

BMI variability and incident diabetes mellitus, Tehran Lipid and Glucose Study (TLGS)

Previous epidemiologic studies debated the association of body mass index (BMI) trends with cardiovascular disease and mortality. This study aimed to evaluate the association of BMI variability and slope with the incidence of Type 2 diabetes mellitus (T2DM) in a sex-stratified 15.8-year follow-up in the population-based Tehran Lipid and Glucose Study (TLGS). Of 10,911 individuals aged 20-60 years, 4981 subjects were included and followed for 15.8-years. The slope coefficient of BMI in the linear regression model represented individuals' BMI trends up to the incidence of DM. The root mean squared error (RMSE) of the BMI linear trend was selected to reflect BMI variability through six follow-ups. Cox proportional hazards regression was used to investigate the association of the baseline BMI, BMI slope and RMSE with the incidence of T2DM among men and women. Multivariable-adjusted HRs of T2DM for each SD increment in BMI slope was 1.18 (95% CI: 0.94-1.48, p = 0.161) in normal weight men and 1.26 (95% CI: 1.10-1.44, p = 0.001) in overweight and obese men. However, in women, each SD increment in BMI slope increased the risk of T2DM with a HR of 1.19 (95% CI: 1.01-1.40, p = 0.039) in normal weight, and 1.14 (95% CI: 1.08-1.19, p < 0.001) in women with BMI ≥ 25 kg/m2. In men with a baseline BMI ≥ 25 kg/m2, BMI-RMSE was associated with a decreased risk of T2DM (HR: 0.71, 95% CI: 0.53-0.93, p = 0.015). Baseline BMI was not associated with the risk of diabetes in men and women. Positive BMI slope is associated with the development of diabetes in both sexes. The association of BMI variability with incident T2DM differs according to sex and baseline BMI. BMI variability is associated with a lower risk of T2DM in overweight and obese men. BMI variability in women and baseline BMI in both gender are not related to the risk of T2DM.

Association of Long-Term Body Weight Variability With Dementia: A Prospective Study

BACKGROUND

Body weight variability (BWV) refers to intraindividual weight loss and gain over a period. The association of long-term BWV with dementia remains unclear and whether this association is beyond body weight change is undetermined.

METHODS

In the Health and Retirement Study, a total of 5 547 dementia-free participants (56.7% women; mean [SD] age, 71.1 [3.2] years) at baseline (2008) were followed up to 8 years (mean = 6.8 years) to detect incident dementia. Body weight was self-reported biennially from 1992 to 2008. BWV was measured as the coefficient of variation utilizing the body weight reported 9 times across 16 years before baseline. Cox-proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Among the 5 547 participants, a total of 427 incident dementia cases were identified during follow-up. Greater long-term BWV was significantly associated with a higher risk of dementia (HR comparing extreme quartiles: 2.01, 95% CI: 1.48-2.72; HR of each SD increment: 1.21, 95% CI: 1.10-1.32; p-trend < .001) independent of mean body weight and body weight change. This significant association was even observed for BWV estimated approximately 15 years preceding dementia diagnosis (HR of each SD increment: 1.13, 95% CI: 1.03-1.23) and was more pronounced for that closer to diagnosis.

CONCLUSION

Our prospective study suggested that greater BWV may be a novel risk factor for dementia.

Adolescent overeating and binge eating behavior in relation to subsequent cardiometabolic risk outcomes: a prospective cohort study

BACKGROUND

Binge eating disorder is bidirectionally associated with obesity and with metabolic syndrome. It is less clear whether overeating and binge eating, or overeating with loss of control, also predicts metabolic risk, and if so, whether these associations are solely attributable to greater weight. The goal of this study was to examine longitudinal associations of overeating and binge eating behavior with cardiometabolic risk markers in adolescence.

METHODS

Adolescents (n = 619) in the Project Viva research study self-reported overeating and binge eating behavior in early adolescence (median 12.9 years, "baseline"). In late adolescence (median 17.4 years, "follow-up"), we assessed outcomes of adiposity and blood pressure, and in a subset of participants (n = 270-424), biomarkers of dyslipidemia, insulin resistance, liver dysfunction, inflammation, and adipokine homeostasis. We conducted multivariable linear regression analyses adjusted for socio-demographics and prenatal obesogenic exposures, and additionally for baseline body mass index (BMI) z-score.

RESULTS

At baseline, 58 (9%) participants reported overeating behavior, and of those, 24 (41%) had binge eating behavior (e.g., overeating accompanied by loss of control). In adjusted models, adolescents with overeating had higher adiposity at follow-up ~ 5 years later (e.g., % body fat 4.03; 95% confidence interval (CI) 1.76, 6.31) than those not reporting overeating behavior; additional adjustment for baseline BMI z-score attenuated associations generally except for % body fat (2.95; 95% CI 1.03, 4.87). Overeating behavior was also associated with higher inflammation and greater adipokine dysfunction, remaining positively associated with interleukin-6 (IL-6) (log-transformed β = 0.42 pg/mL; 95% CI 0.12, 0.73) and negatively with adiponectin (log-transformed β = -0.28 ug/mL; 95% CI - 0.47, - 0.08) even after adjusting for baseline BMI z-score. Overeating behavior was not consistently associated with other outcomes. Adolescents reporting binge eating behavior generally had the greatest adiposity, (e.g., % body fat 5.00; 95% CI 1.74, 8.25) as compared to those without overeating.

CONCLUSIONS

Adolescents reporting overeating and binge eating behavior had higher adiposity and poorer inflammatory and adipokine profiles, but no difference in other outcomes, than adolescents who did not endorse these behaviors. These associations were only partially accounted for by higher baseline BMI z-score. These differences may signal increased risk for future cardiovascular disease.

Variability of adiposity indices and incident heart failure among adults with type 2 diabetes

Background

It remains unclear how the variability of adiposity indices relates to incident HF. This study evaluated the associations of the variability in several adiposity indices with incident heart failure (HF) in individuals with type 2 diabetes (T2DM).

Methods

We included 4073 participants from the Look AHEAD (Action for Health in Diabetes) study. We assessed variability of body mass index (BMI), waist circumference (WC), and body weight across four annual visits using three variability metrics, the variability independent of the mean (VIM), coefficient of variation (CV), and intraindividual standard deviation (SD). Multivariable Cox regression models were used to generate adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for incident HF.

Results

Over a median of 6.7 years, 120 participants developed incident HF. After adjusting for relevant confounders including baseline adiposity levels, the aHR for the highest (Q4) versus lowest quartile (Q1) of VIM of BMI was 3.61 (95% CI 1.91–6.80). The corresponding aHRs for CV and SD of BMI were 2.48 (95% CI 1.36–4.53) and 2.88 (1.52–5.46), respectively. Regarding WC variability, the equivalent aHRs were 1.90 (95% CI 1.11–3.26), 1.79 (95% CI 1.07–3.01), and 1.73 (1.01–2.95) for Q4 versus Q1 of VIM, CV and SD of WC, respectively.

Conclusions

In a large sample of adults with T2DM, a greater variability of adiposity indices was associated with higher risks of incident HF, independently of traditional risk factors and baseline adiposity levels.

Registration-URL:https://clinicaltrials.gov/ct2/show/NCT00000620.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01440-1.

Body Weight Variability and Risk of Cardiovascular Outcomes and Death in the Context of Weight Loss Intervention Among Patients With Type 2 Diabetes

IMPORTANCE

Body weight fluctuation is associated with greater risks of adverse health outcomes. Whether intensive weight loss interventions affect the association of variability in adiposity measures with adverse health outcomes in individuals with type 2 diabetes has not been studied previously.

OBJECTIVE

To evaluate the associations of long-term variability in adiposity indices with cardiovascular disease (CVD) outcomes and whether these associations are affected by an intensive lifestyle intervention among adults with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included participants in the Action for Health in Diabetes (Look AHEAD) trial without CVD at baseline (August 2001 to April 2004). The Look AHEAD study included 16 centers in the United States. Data analysis was performed from December 2020 to June 2021.

EXPOSURES

Variability of body mass index (BMI) and waist circumference (WC) across 4 annual visits, assessed using the coefficient of variation (CV), variability independent of the mean (VIM), and standard deviation (SD).

MAIN OUTCOMES AND MEASURES

Main outcomes were (1) all-cause mortality, (2) cardiovascular deaths (deaths from myocardial infarction [MI] or stroke), and (3) CVD events (MI, stroke, and/or death from cardiovascular causes).

RESULTS

Among 3604 study participants (mean [SD] age, 58.4 [6.6] years; 2240 [62.3%] women; 1364 [37.7%] Black participants; 2404 [66%] White participants), there were 216 CVD events, 33 CVD deaths, and 166 deaths over a median of 6.7 years. In the control group, the hazard ratios (HRs) for the highest quartile (quartile 4) compared with the lowest quartile (quartile 1) of CV of BMI were 4.06 (95% CI, 2.17-7.57), 15.28 (95% CI, 2.89-80.90), and 2.16 (95% CI, 1.21-3.87) for all-cause mortality, CVD mortality, and cardiovascular events, respectively. In the intervention group, the corresponding HRs were 0.99 (95% CI, 0.45-2.16), 1.14 (95% CI, 0.12-10.53), and 0.77 (95% CI, 0.40-1.49) for quartile 4 vs quartile 1. Regarding WC, in the control group, HRs for quartile 4 vs quartile 1 were 1.84 (95% CI, 1.01-3.35), 6.46 (95% CI, 1.16-36.01), and 1.28 (95% CI, 0.72-2.29). In the intervention group, HRs were 1.23 (95% CI, 0.61-2.46), 0.55 (95% CI, 0.15-2.11), and 0.70 (95% CI, 0.39-1.25) for quartile 4 vs quartile 1.

CONCLUSIONS AND RELEVANCE

In this cohort study of individuals with type 2 diabetes, higher variability of adiposity indices was associated with significantly increased risk of CVD outcomes and death in the control group but not in the intensive lifestyle intervention group.

Body weight variability and the risk of cardiovascular outcomes in patients with nonalcoholic fatty liver disease

We investigated the association between body weight variability and the risks of cardiovascular disease and mortality in patients with nonalcoholic fatty liver disease (NAFLD) using large-scale, nationwide cohort data. We included 726,736 individuals with NAFLD who underwent a health examination between 2009 and 2010. NAFLD was defined as a fatty liver index ≥ 60, after excluding significant alcohol intake, viral hepatitis, and liver cirrhosis. Body weight variability was assessed using four indices, including variability independent of the mean (VIM). During a median 8.1-year follow-up, we documented 11,358, 14,714, and 22,164 cases of myocardial infarction (MI), stroke, and all-cause mortality, respectively. Body weight variability was associated with an increased risk of MI, stroke, and mortality after adjusting for confounding variables. The hazard ratios (HRs) (95% confidence intervals) for the highest quartile, compared with the lowest quartile, of VIM for body weight were 1.15 (1.10-1.20), 1.22 (1.18-1.26), and 1.56 (1.53-1.62) for MI, stroke, and all-cause mortality, respectively. Body weight variability was associated with increased risks of MI, stroke, and all-cause mortality in NAFLD patients. Appropriate interventions to maintain a stable weight could positively affect health outcomes in NAFLD patients.

Association between variability in body mass index and development of type 2 diabetes: Panasonic cohort study

INTRODUCTION

Contrasting results have been reported for the association between the variability in body weight and development of diabetes. In the present study, we evaluated the association between the variability in body mass index (BMI) and development of type 2 diabetes in 19 412 Japanese participants without obesity and without body weight gain or loss during the study period.

RESEARCH DESIGN AND METHODS

We recorded body weight of the participants consecutively each year in Panasonic Corporation, Osaka, Japan from 2008 to 2014 to evaluate the variability of BMI. The participants with obesity (BMI ≥25 kg/m²) at baseline and body weight gain or loss from 2008 to 2014 (delta BMI ≥±1 kg/m²) were excluded from the study. In total, 416 participants developed type 2 diabetes from 2015 to 2018. We used coefficient of variation (CV) to represent the variability in BMI during 6 years of the study period.

RESULTS

Cox regression analyses revealed that the risk of developing type 2 diabetes was higher in the fourth quartile (HR 1.33; 95% CI 1.01 to 1.75) of CV of BMI than that in the first quartile (lowest quartile) of CV of BMI after adjusting for multiple confounding factors. The risk for developing diabetes increased by 11.1% per 1% increase in CV of BMI.

CONCLUSIONS

In conclusion, the variability in BMI is a risk factor for the development of diabetes in the Japanese population without obesity and without body weight gain or loss.

The association between weight fluctuation and all-cause mortality: A systematic review and meta-analysis

BACKGROUND

Many observational studies have reported an association between weight fluctuation and all-cause mortality. However, the conclusions obtained from these studies have been unclear.

OBJECTIVE

The current meta-analysis aimed to clarify the association between weight fluctuation and all-cause mortality.

DATA SOURCE

We electronically searched PubMed, Embase, and Web of Science for articles reporting an association between weight fluctuation and all-cause mortality that were published before April 30, 2018.

STUDY APPRAISAL AND SYNTHESIS METHODS

The methodological quality of each study was appraised using the modified Newcastle Ottawa Quality Assessment Scale. The hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were extracted from the included studies and pooled using random-effect models. Meta-regression approaches were also performed to explore sources of between-study heterogeneity.

RESULTS

A total of 15 studies were eligible for the current meta-analysis. The pooled overall HR for all-cause mortality in the group with the greatest weight fluctuations compared with the most stable weight category was 1.45 (95% CI: 1.29-1.63). Considerable between-study heterogeneity was observed, some of which was partially explained by the different follow-up durations used by the included studies. Moreover, publication bias that inflated the risk of all-cause mortality was detected using Egger's test (P = .001).

CONCLUSION

Weight fluctuation might be associated with an increased risk of all-cause mortality.

Association of Weight Fluctuation With Mortality in Japanese Adults

IMPORTANCE

Weight cycling is associated with the risk of mortality from heart disease, but many studies have not distinguished between simple nonlinear (monotone) weight changes and more complex changes that reflect fluctuations.

OBJECTIVE

To assess whether extreme body weight variation is associated with mortality after controlling for nonlinear weight changes.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective clinical cohort study, 4796 Japanese atomic bomb survivors were examined in the clinic as part of a biennial health examination and research program. The study consisted of a 20-year longitudinal baseline period (July 1, 1958, to June 30, 1978) and subsequent mortality follow-up of 27 years (July 1, 1978, to June 30, 2005) Participants were initially between the ages of 20 and 49 years during the baseline period and, throughout the baseline period, had no diagnoses of cardiovascular disease (CVD) or cancer and attended at least 7 of 10 scheduled examinations. Data analysis was performed from October 16, 2015, to May 13, 2016.

EXPOSURES

Residual variability in body mass index (BMI) during the baseline period.

MAIN OUTCOMES AND MEASURES

Outcomes were mortality from ischemic heart disease, cerebrovascular disease, other CVDs combined, other causes (except cancer), and cancer. Root mean squared error was calculated to capture individual residual variation in BMI after adjustment for baseline BMI trends, and the association of magnitude of residual variation with mortality was calculated as relative risk.

RESULTS

In total, 4796 persons (mean [SD] age, 35.0 [7.3] years at first baseline examination; 3252 [67.8%] female; mean [SD] BMI, 21.2 [2.8] at first baseline visit [20.6 (2.4) among men and 21.5 (2.9) among women]) participated in the study. During follow-up, 1550 participants died: 82 (5.3% of all deaths) of ischemic heart disease, 181 (11.7%) of cerebrovascular disease, 186 (12.0%) of other CVDs, 615 (39.7%) of cancer, and 486 (31.3%) of other causes. Magnitude of residual variation in weight was associated with all-cause mortality (relative risk, 1.25 for 1 U of additional variation; 95% CI, 1.06-1.47) and ischemic heart disease mortality (relative risk, 2.49; 95% CI, 1.41-4.38).

CONCLUSIONS AND RELEVANCE

The findings suggest that an association exists between weight variation and heart disease mortality and that weight loss interventions, if deemed to be necessary, should be considered carefully.

Repeatedly measured predictors: a comparison of methods for prediction modeling

BACKGROUND

In literature, not much emphasis has been placed on methods for analyzing repeatedly measured independent variables, even less so for the use in prediction modeling specifically. However, repeated measurements could especially be interesting for the construction of prediction models. Therefore, our objective was to evaluate different methods to model a repeatedly measured independent variable and a long-term fixed outcome variable into a prediction model.

METHODS

Six methods to handle a repeatedly measured predictor were applied to develop prediction models. Methods were evaluated with respect to the models' predictive quality (explained variance R 2 and the area under the curve (AUC)) and their properties were discussed. The models included overweight and BMI-standard deviation score (BMI-SDS) at age 10 years as outcome and seven BMI-SDS measurements between 0 and 5.5 years as longitudinal predictor. Methods for comparison encompassed developing models including: all measurements; a single (here: the last) measurement; a mean or maximum value of all measurements; changes between subsequent measurements; conditional measurements; and growth curve parameters.

RESULTS

All methods, except for using the maximum or mean, resulted in prediction models for overweight of similar predictive quality, with adjusted Nagelkerke R 2 ranging between 0.230 and 0.244 and AUC ranging between 0.799 and 0.807. Continuous BMI-SDS prediction showed similar results.

CONCLUSIONS

The choice of method depends on hypothesized predictor-outcome associations, available data, and requirements of the prediction model. Overall, the growth curve method seems to be the most flexible method capable of incorporating longitudinal predictor information without loss in predictive quality.

Associations of changes in body mass index with all-cause and cardiovascular mortality in healthy middle-aged adults

Background

Conflicting data exist regarding the association of body mass index (BMI) changes with all-cause and cardiovascular (CV) mortality. The current study investigated the association between changes in BMI and all-cause, CV, and non-CV mortality in a large cohort of middle-aged adults.

Methods

A total of 379,535 adults over 40 years of age without pre-existing CV disease or cancer at baseline were enrolled to undergo a series of at least three health examinations of biennial intervals. Changes in BMI between baseline, midpoint follow-up, and final health examination during mean 9.3 years were defined according to the pattern of BMI change as follows: stable, sustained gain, sustained loss, and fluctuation. The relationship between BMI change category and mortality was assessed by multivariate Cox regression reporting hazard ratio (HR) with 95% confidence interval (95% CI).

Results

During a mean follow-up of 10.7 years for mortality, 12,378 deaths occurred from all causes, of which 2,114 were CV and 10,264 were non-CV deaths. Sustained BMI gain was associated with the lower risk of all-cause (HR 0.89, 95% CI: 0.83–0.95), CV (HR 0.84, 95% CI 0.72–0.98), and non-CV mortality (HR 0.90, 95% CI 0.84–0.96) compared with stable BMI. Conversely, sustained BMI loss (HR 1.25, 95% CI 1.19–1.32) and fluctuation (HR 1.13, 95% CI 1.08–1.19) displayed a higher risk of all-cause mortality compared with stable BMI, which was mainly attributable to the increase in non-CV mortality.

Conclusion

Sustained BMI gains were associated with reduced risk of all-cause, CV, and non-CV mortality in middle-aged healthy adults.

Weight Fluctuation and Cancer Risk in Postmenopausal Women: The Women's Health Initiative

Background: Weight cycling, defined by an intentional weight loss and subsequent regain, commonly occurs in overweight and obese women and is associated with some negative health outcomes. We examined the role of various weight-change patterns during early to mid-adulthood and associated risk of highly prevalent, obesity-related cancers (breast, endometrial, and colorectal) in postmenopausal women.Methods: A total of 80,943 postmenopausal women (age, 63.4 ± 7.4 years) in the Women's Health Initiative Observational Study were categorized by self-reported weight change (weight stable; weight gain; lost weight; weight cycled [1-3, 4-6, 7-10, >10 times]) during early to mid-adulthood (18-50 years). Three site-specific associations were investigated using Cox proportional hazard models [age, race/ethnicity, income, education, smoking, alcohol, physical activity, hormone therapy, diet, and body mass index (BMI)].Results: A total of 7,464 (breast = 5,564; endometrial = 788; and colorectal = 1,290) incident cancer cases were identified between September 1994 and August 2014. Compared with weight stability, weight gain was significantly associated with risk of breast cancer [hazard ratio (HR), 1.11; 1.03-1.20] after adjustment for BMI. Similarly, weight cycling was significantly associated with risk of endometrial cancer (HR = 1.23; 1.01-1.49). Weight cycling "4 to 6 times" was most consistently associated with cancer risk, showing a 38% increased risk for endometrial cancer [95% confidence interval (CI), 1.08-1.76] compared with weight stable women.Conclusions: Weight gain and weight cycling were positively associated with risk of breast and endometrial cancer, respectively.Impact: These data suggest weight cycling and weight gain increase risk of prevalent cancers in postmenopausal women. Adopting ideal body-weight maintenance practices before and after weight loss should be encouraged to reduce risk of incident breast and endometrial cancers. Cancer Epidemiol Biomarkers Prev; 26(5); 779-86. ©2017 AACR.

Associations between body fat variability and later onset of cardiovascular disease risk factors

OBJECTIVE

There is current debate regarding whether body weight variability is associated with cardiovascular events. Recently, high body fat percentage (BF%) has been shown to be a cardiovascular risk factor. We therefore hypothesized that BF% variability would present a stronger cardiovascular risk than body weight variability.

METHODS

A single-center retrospective cohort study of medical check-up examinees aged 20 years or older at baseline (2005) was performed. Examinees were followed in 2007, 2009, and 2013-2014. BF% variability in 2005, 2007 and 2009 was calculated as the root-mean square error (RMSE) using a simple linear regression model. Multiple logistic regression models estimated the association between BF%-RMSE and new diagnoses of cardiovascular risk factors occurring between the 2009 and 2013-2014 visits.

RESULTS

In total, 11,281 participants (mean age: 51.3 years old, 48.8% were male) were included in this study. The average BF%-RMSE of our subjects was 0.63, and the average BMI-RMSE was 0.24. The high BF%-RMSE group (76-100th percentile) had a higher incidence of hypertension and a lower incidence of diabetes mellitus than the low BF%-RMSE group (1-25th percentile). This tendency was particularly evident in male participants. BMI-RMSE was not associated with any cardiovascular risks in our study.

CONCLUSIONS

This study indicates that body fat variability has contrasting effects on cardiovascular risk factors, while body weight variability has no significant effects.

Long-term weight-change slope, weight fluctuation and risk of type 2 diabetes mellitus in middle-aged Japanese men and women: findings of Aichi Workers' Cohort Study

OBJECTIVE

This study aims to investigate the association of long-term weight-change slopes, weight fluctuation and the risk of type 2 diabetes mellitus (T2DM) in middle-aged Japanese men and women.

METHODS

A total of 4234 participants of Aichi Workers' Cohort Study who were aged 35-66 years and free of diabetes in 2002 were followed through 2014. Past body weights at the ages of 20, 25, 30, 40 years, and 5 years before baseline as well as measured body weight at baseline were regressed on the ages. Slope and root-mean-square-error of the regression line were obtained and used to represent the weight changes and the weight fluctuation, respectively. The associations of the weight-change slopes and the weight fluctuation with incident T2DM were estimated by Cox proportional hazards models.

RESULTS

During the median follow-up of 12.2 years, 400 incident cases of T2DM were documented. After adjustment for baseline overweight and other lifestyle covariates, the weight-change slopes were significantly associated with higher incidence of T2DM (hazard ratio (HR): 1.80, 95% confident interval (CI): 1.17-2.77 for men; and HR: 2.78, 95% CI: 1.07-7.23 for women), while the weight fluctuation was not (HR: 1.08, 95% CI: 1.00-1.18 for men and HR: 1.02, 95% CI: 0.84-1.25 for women).

CONCLUSIONS

Regardless of the presence of overweight, the long-term weight-change slopes were significantly associated with the increased risk of T2DM; however, the weight fluctuation was not associated with the risk of T2DM in middle-aged Japanese men and women.

C-reactive protein levels in stable COPD patients: a case-control study

Background

Previous studies have documented that C-reactive protein (CRP) levels are increased in stable COPD patients. However, most studies have also shown that higher CRP levels are observed in patients with comorbidities like diabetes mellitus and cardiovascular disease. We aimed to investigate if CRP levels are increased in stable COPD patients, and if there is an association between CRP levels and pulmonary function tests and clinical characteristics.

Methods

We conducted a case-control study in a tertiary care, university-affiliated hospital. COPD patients and controls were matched for sex and age in a 2:1 matching ratio. We included only those patients who had quit smoking. CRP levels were determined and pulmonary function tests were performed in both the groups.

Results

A total of 60 COPD patients and 30 controls were included in the analysis. The study subjects had a mean age of 64.8±8.5 years in COPD group and 64.3±9.2 years in control group (P=0.214). The median of CRP levels was 3.17 mg/L (interquartile range [IQR]: 1.73–5.99 mg/L) in COPD group and 2.13 mg/L (IQR: 1.18–7.69 mg/L) in control group (P=0.370). There were 34 (56.7%) patients in COPD group and 14 (46.7%) patients in control group with CRP levels greater than 3 mg/dL (P=0.382). Using bivariate correlations, we found significant positive correlations in COPD patients between body mass index (BMI) and CRP (r=0.3, P=0.045), and between CRP and forced vital capacity (FVC, % of predicted) (r=−0.3; P=0.023). In a multivariate model, female sex and FVC (% of predicted) were associated with a CRP value greater than 3 mg/dL in the COPD group.

Conclusion

The levels of CRP in the stable COPD patients were not significantly different when compared to those in the control subjects. Female sex and FVC (% predicted) were associated with CRP levels greater than 3 mg/dL in the COPD group.

Weight fluctuation during childhood and cardiometabolic risk at young adulthood

OBJECTIVES

To test the hypothesis that greater weight fluctuation between 2 and 6 years is associated with an increase in weight measures (such as body mass index [BMI]) and cardiometabolic risk in young adulthood.

STUDY DESIGN

Weight fluctuation (determined by BMI SD scores) was measured at least 3 times between the ages of 2 and 6 years in 166 girls and 116 boys from the Terneuzen Birth Cohort. Cardiometabolic risk factors in young adulthood include components of the metabolic syndrome and weight. The extent of weight fluctuation was determined by assessing each individual's SE (or variation) around each individual's linear regression slope (or weight slope). The obtained variation scores were subsequently related to adult BMI, other weight measures, and cardiometabolic risk factors.

RESULTS

In girls, greater weight fluctuation between 2 and 6 years was statistically significantly related to greater adult weight measures (1.08; 95% CI 1.01-1.15) and nonsignificantly with the metabolic syndrome. For boys weight fluctuation was not associated with adult weight (1.04; 95% CI 0.97-1.11), but weight slope was statistically significantly associated with adult overweight.

CONCLUSIONS

The results suggest that weight fluctuations during early childhood are predictive for adult overweight in girls. For boys weight slope instead of weight fluctuation is predictive for adult overweight.

The association of rate of weight gain during early adulthood with the prevalence of subclinical coronary artery disease in recently diagnosed type 2 diabetes: the MAXWEL-CAD study

OBJECTIVE

To investigate the association of the rate of weight gain (Ratemax_wt) between the age of 20 years and the age of maximum lifetime weight gain with indicators of subclinical coronary artery disease (CAD) at the time of diagnosis of type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

We studied 1,724 consecutive Korean subjects aged ≥30 years with recently diagnosed (within 3 months) T2D and one or more cardiovascular risk factors to investigate the association of Ratemax_wt with subclinical CAD. We used 64-slice cardiac computed tomography angiography to evaluate the degree of coronary artery stenosis, multivessel involvement, plaque characteristics, and coronary artery calcium score (CACS). Body weight at age 20 years (Wt20y) was obtained from participant records. Participants recalled their maximum weight (Wtmax) before T2D diagnosis and age at maximum weight (Agemax_wt). The Ratemax_wt was calculated as (Wtmax - Wt20y) / (Agemax_wt - 20 years).

RESULTS

The prevalence of coronary artery stenosis (≥50%), multivessel involvement (two or more vessels), plaque characteristics, and CACS ≥100 were 11.4%, 6.6%, 19.7%, and 12.8%, respectively. Mean Wt20y and Wtmax were 60.1 ± 10.5 and 73.0 ± 11.5 kg, respectively. Mean Agemax_wt was 41.3 ± 10.7 years, and Ratemax_wt was 0.59 ± 0.56 kg/year. After adjusting for cardiovascular risk factors, including current BMI, the highest quarter of prior weight gain was significantly associated with coronary artery stenosis, multivessel involvement, and plaque characteristics, particularly mixed and noncalcified plaque.

CONCLUSIONS

The findings suggest that a greater rate of prior weight gain may accelerate the development of subclinical vascular complications in patients with newly diagnosed T2D.

Association between body mass index and high-sensitivity C-reactive protein in male Japanese

We divided subjects into hs-CRP of ≤1.0 mg/l and >1.0 mg/l, and investigated the relationship between hs-CRP and basic attributes, lifestyle and health checkup test results. In particular, hs-CRP increased significantly as BMI increased, and hs-CRP of >1.0 mg/l was seen in about 40% of people with BMI of ≥25 kg/m(2) and 75% with BMI of ≥ 30 kg/m(2). Persons with 3 or more abnormalities in BMI, blood pressure, serum lipid and glucose were found in 20.0% of those with hs-CRP >1.0 mg/l, while 4.3% in hs-CRP ≤ 1.0 mg/l. The present findings have suggested that hs-CRP > 1.0 mg/l can be an indicator for obesity-related risks in male Japanese.

Effects of long-term developmental patterns of adiposity on levels of C-reactive protein and fibrinogen among North-American men and women: the Spokane Heart Study

This study examined the heterogeneity in BMI development by identifying distinct developmental trajectories. These trajectories were further investigated by relating them to markers of low-grade inflammation later in life. Data from approximately 400 healthy volunteers participating in the Spokane Heart Study were collected in 2-year intervals, and four waves of data were available for the current analyses. Body weight was measured by BMI and low-grade inflammation by high-sensitivity C-reactive protein (CRP) and fibrinogen. Up to date statistical techniques, i.e., latent class growth models, were used to analyse heterogeneity in body weight, and linear regressions were run to analyse possible associations between trajectories of body weight and CRP/fibrinogen levels. Six trajectories were identified (three stable, two increasing, and one decreasing) which differed significantly on CRP/fibrinogen levels, highlighting the importance of weight trajectories. The differences were only partly explained by variations in lifestyle habits.

C-reactive protein and lung diseases

C-reactive protein (CRP), a member of the pentraxin family of plasma proteins, is one of the most distinctive acute phase reactants. In response to inflammation, cell damage or tissue injury, plasma level of CRP rapidly and dramatically increases up to 1000-fold, a phenomenon that has been used for years to monitor infections and many destructive/inflammatory conditions. The magnitude of CRP increase usually correlates with the severity of injury or inflammation and reflects an important physiological role of this interesting but still under-investigated protein. It is now generally accepted that CRP is involved in host defense and inflammation. However, the exact function of this protein in health and disease remains unclear. Many studies have demonstrated that in different pathophysiological conditions CRP might be involved in the regulation of lung function and may participate in the pathogenesis of various pulmonary disorders. The fluctuation of CRP concentrations in both alveolar fluid and serum associated with different pulmonary diseases suggests its important role in lung biology. Discussion of the still controversial functions of CRP in lung physiology and diseases is the main focus of this review.

An association between body mass index and high-sensitivity C-reactive protein concentrations is influenced by age in community-dwelling persons

BACKGROUND

High sensitivity C-reactive protein (hsCRP) is an acute phase reactant and a sensitive marker of inflammation. Age and adiposity can potentially promote the production of C-reactive protein (CRP). However, only a few studies have investigated any interaction between age and adiposity on hsCRP concentrations.

METHODS

We recruited 822 men (mean age, 61 ± 14 years) and 1097 women (63 ± 12 years) during their annual health examination from a single community. We cross-sectionally examined whether age, body mass index (BMI), and the interaction are significantly associated with hsCRP concentrations, independent of confounding factors.

RESULTS

Multiple linear regression analyses for hsCRP showed that in men, age (β = 0.169, P < 0.001) and BMI (β = 0.114, P = 0.004) as well as smoking status, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), uric acid, and gamma-glutamyl transferase (GGT) were significantly associated with hsCRP; and in women, age (β = 0.203, P < 0.001) and BMI (β = 0.225, P < 0.001) as well as HDL-C, fasting plasma glucose (FPG), uric acid, GGT and high-molecular weight adiponectin were significantly associated with hsCRP. In addition to their direct associations, the interaction between age and BMI was also a significant and independent determinant for hsCRP in both men (F = 4.407, P = 0.036) and women (F = 5.487, P = 0.019). In participants aged < 75 years, overweight (BMI ≥ 25.0 kg/m(2)) persons were more likely to have a prevalence of elevated hsCRP concentrations (≥ 1.00 mg/L) compared with the normal-weight (BMI <22.0 kg/m(2)), but such an association was not observed in those aged ≥ 75 years.

CONCLUSIONS

Adiposity promotes low-grade systemic inflammation in community-dwelling persons aged <75 years.

Obesity is an independent determinant of ischemia-modified albumin

OBJECTIVE

We have measured ischemia-modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS) and high-sensitivity C-reactive protein (hsCRP) levels in obese and normal-weight subjects to investigate if IMA can be used as a biomarker of oxidative stress and inflammation and if IMA was an independent determinant of obesity or not.

METHODS

The study was performed on 92 obese subjects (20 male, 72 female) aged 38 ± 11 years and 78 normal-weight controls (19 male, 59 female) aged 37 ± 11 years. Serum lipids, IMA, TAS, TOS, and hsCRP levels of the subjects were measured.

RESULTS

IMA (p < 0.05), TOS (p < 0.001), and hsCRP (p < 0.001) levels of the obese subjects were significantly higher, whereas TAS levels were significantly lower (p < 0.05) than those of the controls after adjustment for age and gender. In the linear regression analysis, waist circumference (r² = 0.139, p < 0.01), BMI (r² = 0.136, p < 0.01) and insulin (r² = 0.120, p < 0.05) were shown to be significant independent determinants of IMA levels.

CONCLUSIONS

We have found that oxidative stress and inflammation were increased and antioxidative defense was decreased, which resulted in increased levels of IMA, a biomarker of ischemia, in obese subjects. Also, obesity and insulin were found to be independent determinants of IMA. Thus, obese subjects are under high risk of ischemia, and IMA may be used as a biomarker of oxidative stress and ischemia. Further larger investigations are needed to confirm this opinion.

Changes in C-reactive protein during weight loss and the association with changes in anthropometric variables in men and women: LIFE Study

OBJECTIVE

To investigate whether sex differences exist in the pattern of change in C-reactive protein (CRP) levels during weight loss, and whether the associations between weight change and CRP change differ by the types of anthropometric variables.

DESIGN

Longitudinal, prospective analysis of subjects participating in an intentional weight loss trial (the Lose It For Ever: LIFE Study) followed-up for 30 months.

SUBJECTS

A total of 212 healthy, obese men and women (age: 23-77 years, body mass index (BMI): 30-39 kg m(-2)) took part in this study.

MEASUREMENTS

BMI, waist and hip circumferences, and waist-to-hip ratio, CRP and lifestyle variables repeatedly measured at baseline, 6, 12, 18 and 30-month follow-up.

RESULTS

Weight change was J shaped with a nadir at 12 months in both men and women (P for month(2) <0.0001). CRP level was consistently higher in women than in men, but the differences were less prominent and were not statistically significant at 12- and 18-month follow-up. CRP changes between any two consecutive visits were significantly associated with changes in BMI during the same period in women. However, the associations between CRP changes and changes in waist or hip circumference were not as consistent, especially between 18- and 30-month follow-up when CRP significantly increased. The associations in men were generally similar among the different anthropometric measures. The association between changes in BMI and CRP was stronger in men than in women.

CONCLUSION

BMI change generally correlated well with CRP changes in both men and women in the course of follow-up. Significant sex difference in CRP level at baseline diminished at 12- and 18-month follow-up, when both sexes had maintained the lost weight.

Variability of body weight, pulse pressure and glycaemia strongly predict total mortality in elderly type 2 diabetic patients. The Verona Diabetes Study

BACKGROUND

Ageing is characterized by a decreased functional reserve, a concept defined as homeostenosis. We assessed the impact of long-term exposure to the average value (mean) or to the variability (coefficient of variation) of fasting glycaemia, body mass index (BMI) and pulse pressure on total mortality in a cohort of type 2 diabetic patients.

METHODS

Fasting glycaemia, BMI and pulse pressure values were collected over a period of 3 years in 1 319 type 2 diabetic patients who were subsequently followed up for 10 years. For each patient, the means and the coefficients of variation of fasting glycaemia, BMI and pulse pressure were computed. The adverse impact of these risk factors on total mortality was assessed in patients aged < 65 years (n = 565) and in those aged > or = 65 years (n = 754), separately.

RESULTS

During the 10 years of follow-up, 438 patients died. In younger diabetic patients, the means of fasting glycaemia [hazard ratio (HR) of III tertile versus I tertile = 2.11, 95% confidence interval (CI): 1.22-3.64], BMI (HR = 1.88, 1.12-3.14) and pulse pressure (HR = 2.36, 1.34-4.16) were independently associated with total mortality, while in older patients they were not. In contrast, the coefficients of variation of glycaemia (HR = 1.56, 1.17-2.08), BMI (HR = 1.34, 1.03-1.75) and pulse pressure (HR = 1.34, 1.03-1.74) independently predicted total mortality only in older patients.

CONCLUSIONS

Our findings suggest that the variability of fasting glycaemia, body weight and blood pressure (BP) is independently associated with an increased risk of all-cause mortality in older type 2 diabetic patients. Future studies are required to confirm the reproducibility of our findings.

Changes and variations of body weight as risk factors for coronary heart disease

Introduction Weight variations are a common phenomenon. Therefore, concern has been raised about the association between weight changes and weight variations and coronary heart disease (CHD). The aim of this study was to estimate the influence of weight change and weight variations as risk factors for coronary heart disease. Materials and methods The investigation was conducted as an observational cross-sectional study, including 102 participants of both genders: 61 patients with CHD and 41 healthy controls. All participants underwent anthropometric measurements and completed a questionnaire that included 1) weight changes in adulthood (maximum and minimum weight), 2) presence and number of weight variations in the 10 years prior to the onset of disease and 3) the size of weight change (weight gain or weight loss in kg). One weight variation was defined as weight loss followed by weight gain for more than 10% of body weight, or about 7 kg. Multivariant logistic regression was used for the estimation of significant predictors for the occurrence of coronary heart disease. Results Participants with CHD had higher values of body weight in adulthood compared to healthy controls, larger number of weight variations in the last 10 years, and more frequently reported weight gain and weight loss for more than 10 kg. The highest risk for the occurrence of coronary heart disease was observed for participants who had more than 3 weight variations for 10% (OR=2.13; 95%CI=0.98-5.48), those with weight loss over 10 kg (OR=2.16; 95%CI=1.71-2.72) and those with weight gain over 10 kg (OR=2.71; 95%CI=1.08-6.83), regardless of gender, age, smoking, body mass index and blood pressure. Discussion Several mechanisms are suggested to explain the relationship between weight changes and variations and coronary heart disease, including changes in plasma lipid levels, insulin levels, decrease of HDL cholesterol, increase of C-reactive protein and increase of blood pressure. Conclusion This study suggests that frequent and very intense weight changes can be considered important predictors for the occurrence of coronary heart disease.

Pathophysiologic mechanisms of obesity and related metabolic disorders: an epidemiologic study using questionnaire and serologic biomarkers

BACKGROUND

It is still unclear whether individuals with the same degree of obesity but different weight histories since young adulthood have different insulin concentration, prevalence of metabolic syndrome components and their clustering.

METHODS

A cross-sectional study was conducted on 3,399 (for weight difference analysis) and 1,879 (for weight fluctuation analysis) Japanese men aged 40-59 years. Weight difference was calculated by subtracting the recalled weight at about 25 years old from the current weight. The root mean square error around the slope of weight on age (weight - RMSE) was calculated by a simple linear regression model, in which the subject's actual weights at ages 20, 25, 30, 40 years and 5 years prior to the study, as well as current weight, were dependent variables against the subject's age as the independent variable. Each metabolic syndrome component was defined as follows: serum triglycerides ≥150 mg/dL; HDL-cholesterol <40 mg/dL; fasting glucose ≥110 mg/dL; and blood pressure ≥140/90 mm Hg.

RESULTS

Those who gained <10%, <20%, or 20% or more in weight had a significantly higher than unity odds ratio of having two or more metabolic syndrome components in relation to those whose weight remained stable: 1.28 (95% confidence interval: 0.95-1.73), 2.49 (1.91-3.24), and 5.30 (3.97-7.07), respectively. Weight-RMSE was significantly and positively associated with fasting insulin concentration independent of current weight, weight-slope or other lifestyle-related factors.

CONCLUSIONS

Metabolic syndrome components would likely tend to cluster more in individuals with large weight gain on a physiologic basis characterized by high fasting insulin concentration. Furthermore, weight fluctuation was suggested to increase the risk of fasting hyperinsulinemia.

What does minor elevation of C-reactive protein signify?

Reports of the predictive value of minor elevation of serum C-reactive protein (CRP) levels (between 3 and 10 mg/L) for atherosclerotic events have generated considerable interest, as well as a degree of controversy and confusion. CRP concentrations in this range are found in about one third of the American population. To better understand the mechanisms underlying minor elevation of CRP, we have surveyed its reported associations with a variety of states and conditions. It has become clear that even minimal environmental irritants and inflammatory stimuli elicit a minor CRP response. Minor CRP elevation has been found associated with a number of genetic polymorphisms, with membership in different demographic and socioeconomic groups, with a variety of dietary patterns and with many medical conditions that are not apparently inflammatory. Finally, minor CRP elevation bears negative prognostic implications for many conditions, particularly age-related diseases, and predicts mortality in both diseased and apparently healthy individuals. In sum, minor CRP elevation is associated with a great many diverse conditions, some of which are, or may prove to be, causal. Many of these reported associations imply a mild degree of tissue stress or injury, suggesting the hypothesis that the presence of distressed cells, rather than a resulting inflammatory response, is commonly the stimulus for CRP production.

Major depression predicts an increase in long-term body weight variability in young adults

OBJECTIVE

To test the hypothesis that major depression predicts an increase in long-term body weight variability (BWV).

RESEARCH METHODS AND PROCEDURES

This was a prospective community-based single-age cohort study of young adults (N = 591) followed between the ages of 19 and 40. Following initial screening, information was derived from six subsequent semistructured diagnostic interviews conducted by mental health professionals. Major depression was diagnosed on the basis of DSM criteria. BWV was defined as the root mean square error of a regression line fitted to each individual's BMI values over time. Multiple regression analysis was used to test the association between major depression and BWV while controlling for potentially confounding variables including antidepressant treatment, eating disorder symptoms, and physical activity. We used random effects models to determine the temporal relationship between repeated measures of major depression and body weight change.

RESULTS

A highly significant positive association between major depression and BWV was found, whereas major depression was not associated with BMI level or BMI trend. Depression severity showed a dose-response-type relationship with the magnitude of BWV. After controlling for potentially confounding variables including antidepressant use, eating disorder symptoms, smoking, and physical activity, major depression remained a significant predictor of BWV (beta= 0.13, p < 0.001). Longitudinal analysis revealed a unidirectional association between major depression and a later increase in body weight change rate irrespective of antidepressant medication.

DISCUSSION

Results from this study implicate depression as an important risk factor for increased BWV. Given increasing evidence for a link between major depression and both diabetes and cardiovascular disease, current results encourage further research on depression, BWV, and negative health outcomes.

Behavioural treatments for chronic systemic inflammation: effects of dietary weight loss and exercise training

Persistent low-grade inflammation, as indicated by higher circulating levels of inflammatory mediators such as C-reactive protein, interleukin-6 and tumour necrosis factor-alpha, is a strong risk factor for several chronic diseases. There are data indicating that decreasing energy intake and increasing physical activity may be effective therapies for reducing overall inflammation. Evidence is strong that circulating levels of inflammatory markers are elevated with total and abdominal obesity, possibly owing to a higher secretion rate of cytokines by adipose tissue in obese people. Moreover, very-low-energy dietary weight loss reduces both circulating markers of inflammation and adipose-tissue cytokine production. Data from several large population-based cohorts show an inverse association between markers of systemic inflammation and physical activity or fitness status; small-scale intervention studies support that exercise training diminishes inflammation. Dietary weight loss plus exercise is likely more effective than weight reduction alone in reducing inflammation. To date, data from randomized, controlled trails designed to definitively test the effects of weight loss or exercise training, or both, on inflammation are limited. Future studies are required to define the amount of weight loss needed for clinically meaningful reductions of inflammation; in addition, fully powered and controlled studies are necessary to clarify the effect of exercise training on chronic, systemic inflammation.

Long-Term Body Weight Fluctuation is Associated With Metabolic Syndrome Independent of Current Body Mass Index Among Japanese Men

BACKGROUND

The relation between weight fluctuation and the risk of cardiovascular disease (CVD) is fairly consistent, although the physiologic basis for the relationship is uncertain. In the present study the association between long-term weight fluctuation and the development of metabolic syndrome (MS), a potent CVD risk factor, was investigated.

METHODS AND RESULTS

A cross-sectional study of 664 Japanese men aged 40-49 years was conducted. The root mean square error around the slope of weight on age (weight - RMSE) was calculated by a simple linear regression model, in which the subject's actual weights at ages 20, 25, 30 years and 5 years prior to the study, as well as current weight, were dependent variables against the subject's age as the independent variable. Weight-RMSE was significantly and positively associated with the prevalence of each MS components (high blood pressure, hypertriglyceridemia, low-high density lipoprotein-cholesterol, high fasting glucose, and obesity). Such associations, as well as clustering of the MS component together with RMSE increase, were apparent among subjects with body mass index (BMI) <25 kg/m2, although the prevalence of MS or its components was much higher among overweight subjects (BMI >or=25 kg/m2).

CONCLUSIONS

Development of MS possibly explains the risk of CVD not only in overweight or obese persons, but also in normal-weight persons with large weight fluctuation.