Body mass index and short-term weight change in relation to mortality in Dutch women after age 50 y

Weight change and all-cause and cause-specific mortality: A 25-year follow-up study

BACKGROUND

Whether the dynamic weight change is an independent risk factor for mortality remains controversial. This study aimed to examine the association between weight change and risk of all-cause and cause-specific mortality based on the Linxian Nutrition Intervention Trial (NIT) cohort.

METHODS

Body weight of 21,028 healthy residents of Linxian, Henan province, aged 40-69 years was measured two times from 1986 to 1991. Outcome events were prospectively collected up to 2016. Weight maintenance group (weight change <2 kg) or stable normal weight group was treated as the reference. Cox proportional hazard model was performed to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) to estimate the risk of mortality.

RESULTS

A total of 21,028 subjects were included in the final analysis. Compared with the weight maintenance group, subjects with weight loss ≥2 kg had an increased risk of death from all-cause (HR All-cause  = 1.14, 95% CI: 1.09-1.19, P  <0.001), cancer (HR Cancer  = 1.12, 95% CI: 1.03-1.21, P  = 0.009), and heart disease (HR Heart diseases  = 1.21, 95% CI: 1.11-1.31, P  <0.001), whereas subjects with weight gain ≥5 kg had 11% (HR Cancer  = 0.89, 95% CI: 0.79-0.99, P  = 0.033) lower risk of cancer mortality and 23% higher risk of stroke mortality (HR Stroke  = 1.23,95% CI: 1.12-1.34, P  <0.001). For the change of weight status, both going from overweight to normal weight and becoming underweight within 5 years could increase the risk of total death (HR Overweight to normal = 1.18, 95% CI: 1.09-1.27; HR Becoming underweight = 1.35, 95% CI: 1.25-1.46) and cancer death (HR Overweight to normal = 1.20, 95% CI: 1.04-1.39; HR Becoming underweight = 1.44, 95% CI: 1.24-1.67), while stable overweight could increase the risk of total death (HR Stable overweight = 1.11, 95% CI: 1.05-1.17) and death from stroke (HR Stable overweight = 1.44, 95% CI: 1.33-1.56). Interaction effects were observed between age and weight change on cancer mortality, as well as between baseline BMI and weight change on all-cause, heart disease, and stroke mortality (all Pinteraction  <0.01).

CONCLUSIONS

Weight loss was associated with an increased risk of all-cause, cancer, and heart disease mortality, whereas excessive weight gain and stable overweight were associated with a higher risk of stroke mortality. Efforts of weight management should be taken to improve health status.

TRIAL REGISTRATION

https://classic.clinicaltrials.gov/ , NCT00342654.

Association between body mass index change and mortality in critically ill patients: A retrospective observational study

OBJECTIVE

Previous studies have emphasized the association between baseline body mass index (BMI) and mortality in patients during a stay in the intensive care unit (ICU). However, to our knowledge, few studies have focused on BMI change during an ICU stay. The aim of this study was to explore the prognostic value of BMI change during ICU hospitalization.

METHODS

This was a multicenter, retrospective cohort study with data extracted from the eICU Collaborative Research Database. Logistic regression models were used to explore the relationship between BMI change and mortality in ICU patients. BMI change was calculated as follows: {[discharge ICU weight (kg) - admission ICU weight (kg)] / height (m)²]}. Interaction and subgroup analyses were conducted for patients grouped with baseline BMI on ICU admission (≥30 versus 25-29.9 versus <25 kg/m²), Acute Physiology and Chronic Health Evaluation (APACHE) IV score (<53 versus ≥53), and ICU length of stay (≥3 versus <3 d).

RESULTS

Compared with those with weight loss (n = 17 134), patients with weight gain during ICU hospitalization (n = 17 436) were associated with higher hospital mortality (odds ratio [OR], 1.251; 95% confidence interval [CI], 1.155-1.356; P < 0.001) and ICU mortality (OR, 1.360; 95% CI, 1.227-1.506; P < 0.001) after multivariable adjustment. The associations remained robust in patients with different baseline BMI levels and were especially remarkable among those with higher APACHE IV score and the longer ICU stay.

CONCLUSIONS

The present study exposed the potential hazard of increasing BMI for hospital and ICU mortalities during ICU hospitalization and indicating that patients in the ICU may benefit from a more balanced nutritional strategy.

Weight loss and all-cause mortality: A propensity score matching cohort study

BACKGROUND

Weight loss was supposed to help with decreasing risk of premature mortality. However, results on this topic remain debatable and limited by study design.

OBJECTIVE

The present study aimed to investigate the association between weight loss and all-cause mortality among US adults with overweight or obesity in a national cohort study by using propensity score matching (PSM) analysis.

METHODS

A total of 5486 pairs of participants were matched in the National Health and Nutrition Examination Survey (NHANES, 2003-2015) after PSM. Hazard ratios (95% confidence intervals) (HRs (95% CIs)) were employed to evaluate the association between weight loss indicated by long-term weight loss (LTWL) and all-cause mortality by using Cox proportional hazards regression models.

RESULTS

During a median follow-up of 6.8 years, 674 participants died from all-cause mortality. In each PSM match, compared with participants with LTWL < 5%, the HRs (95% CIs) for participants with LTWL of 5-9.9% (2877 pairs), 10-14.9% (1315 pairs), and ≥ 15% (1294 pairs) were 1.18 (0.83-1.68) (P = 0.366), 1.65 (1.17-2.34) (P = 0.005), and 1.91 (1.21-3.00) (P = 0.006), respectively. The significant increased risk of all-cause mortality for LTWL ≥ 15% remained among male, female, participants aged ≥ 65 years, without weight loss intention, with non-communicable diseases, and without exceeding estimated energy requirement.

CONCLUSION

Weight loss especially for being ≥ 15% should be cautious for US adults with overweight or obesity.

Behavioral Lifestyles and Survival: A Meta-Analysis

The aim of the study is to determine the association between Behavioral Lifestyles (regular physical activity, healthy diet, sleeping, and weight control) and longevity in the elderly. A search strategy was conducted in the PsycInfo, Medline, PubMed, Web of Science (WoS), and Scopus databases. The primary outcome was mortality/survival. Four variables (mean of participant's age at the baseline of the study, follow-up years of the study, gender, and year of publication) were analyzed to evaluate the role of potential moderators. Ninety-three articles, totaling more than 2,800,000 people, were included in the meta-analysis. We found that the lifestyles analyzed predict greater survival. Specifically, doing regular physical activity, engaging in leisure activities, sleeping 7-8 h a day, and staying outside the BMI ranges considered as underweight or obesity are habits that each separately has a greater probability associated with survival after a period of several years.

Short-, Medium-, and Long-term Weight Changes and All-Cause Mortality in Old Age: Findings From the National Survey of the Japanese Elderly

BACKGROUND

Recent studies, predominantly in Western populations, suggest that both weight loss and weight gain are associated with an increased mortality risk in old age. However, evidence of this association in older Asian populations remains sparse. This study aimed to examine the association between weight change and all-cause mortality in a nationally representative sample of community-dwelling older Japanese people.

METHODS

Data were obtained from the National Survey of the Japanese Elderly, which included 4869 adults aged ≥60 years. Participants were followed for up to 30 years. We considered 3 indicators of weight change according to the follow-up interval: short-term (3 years), medium-term (6-7 years), and long-term (12-13 years). Weight change was classified as loss ≥ 5%, loss 2.5%-4.9%, stable (±2.4%), gain 2.5%-4.9%, and gain ≥ 5%. Cox proportional hazards models were used to calculate the relative mortality risk of each weight change category.

RESULTS

Weight loss ≥ 5% for all intervals was associated with higher mortality than stable weight and the effects were largely similar across all 3 intervals (hazard ratio [95% confidence interval]: 1.36 [1.22-1.51] for short-term, 1.36 [1.22-1.51] for medium-term, and 1.31 [1.11-1.54] for long-term). A similar pattern of results was observed among the young-old and old-old, and among men and women. The effect of weight loss on higher mortality was greater among those with a lower body mass index at baseline.

CONCLUSIONS

These findings could inform clinical and public health approaches to body-weight management aimed at improving the health and survival of older adults, particularly in Asian populations.

Age-Related Difference in Weight Change and All-Cause Mortality in Middle-Aged and Older Korean Populations: Korean Longitudinal Study of Aging

Background

Obesity is associated with increased mortality as a significant risk factor for chronic diseases, including cardiovascular diseases and cancer. Several people believe that weight gain is harmful, and weight loss helps maintain health. However, some studies have shown that weight loss, particularly among older adults, is more likely to increase the risk of mortality than weight gain.

Methods

We used data for the cohort of the Korean Longitudinal Study of Aging, which is a nationwide stratified multi-stage sample of adults aged 45 years. The all-cause mortality risk was assessed using the survival status and the number of months of survival calculated from 2006 (baseline year) to 2016. Cox proportional hazard regression were used to study the causal link between weight change and all-cause mortality risk.

Results

The results showed interactive associations between weight loss and mortality among middle-aged and older adults. The hazard ratio was 1.62 (95% confidence interval [CI], 1.10–2.40) for the participants aged 45–65 years with weight losses greater than 5 kg and 1.56 (95% CI, 1.29–1.89) for those older than 65 years with weight losses greater than 5 kg. The results for the group with weight gain above 5 kg were not significant. Middle-aged and older men showed an increase in all-cause mortality associated with weight loss of more than 5 kg, but only the older women showed significant results.

Conclusion

This large-scale cohort study in Korea showed a relationship between weight loss and all-cause mortality in middle-aged and older individuals.

Impact of Bariatric Surgery on Women Aerobic Exercise Capacity

RATIONALE

Bariatric surgery has a considerable positive effect on weight loss and on metabolic and cardiovascular risks. It has therefore been extensively used this last decade to overcome obesity. However, the impact of this surgery on exercise capacity remains unclear. The aim of this study is to clarify the impact of a surgically induced weight loss on aerobic exercise capacity (VO₂max) in a specific middle-aged female population.

METHODS

Forty-two women with a body mass index > 40 kg/m² (age, 42 ± 13 years; weight, 117 ± 15 kg) underwent blood analyses and a cardiopulmonary exercise test (CPET) before and 1 year after bariatric surgery. CPET was performed on a cycloergometer. The first ventilatory threshold (VT1) was measured according to the V-slope method.

RESULTS

Absolute VO₂max was reduced by 10% after surgery (2.0 ± 0.4 vs 1.8 ± 0.4 l/min, p < 0.01) or increased when corrected for body weight (18 ± 4 vs 23 ± 4 l/min/kg, p < 0.001) or unchanged when expressed as percentage of predicted values (111 ± 21 vs 105 ± 22, p = 0.06). Weight loss did not affect ventilatory or chronotropic response but increased maximal respiratory exchange ratio (RER) (p < 0.001), decreased maximal O₂pulse (p < 0.05) and VT1 in milliliters per minute (p < 0.01). By multivariable analysis, decreased absolute VO₂max after weight loss was associated with increased maximal RER and reduced maximal O₂pulse (p < 0.05, p < 0.01 respectively), possibly related to a muscular mass limitation.

CONCLUSIONS

Weight loss induced by bariatric surgery may reduce aerobic capacity in women in relation to muscle mass loss.

Weight change is associated with increased all-cause mortality and non-cardiac mortality among patients with type 2 diabetes mellitus

BACKGROUND

It is unclear whether changes in weight affect subsequent adverse events in patients with type 2 diabetes mellitus (T2DM) already at high risk of cardiovascular disease (CVD).

METHODS AND RESULTS

This is a post hoc analysis of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study data to examine the relationship between changes in weight and adverse events. Patients were divided into groups based on changes in body mass index (BMI): stable weight, gain or loss of BMI ≤1.5 kg/m²; moderate weight gain, BMI gain of 1.5-5 kg/m²; pronounced weight gain, BMI gain >5 kg/m²; moderate weight loss, BMI loss of 1.5-5 kg/m²; and pronounced weight loss, BMI loss >5 kg/m². The primary endpoint of the present study was all-cause mortality. Secondary endpoints were cardiac death, non-fatal myocardial infarction (MI), and non-cardiac mortality. A total of 9372 T2DM patients with a mean follow-up of 8.08 ± 3.00 years were included for analysis. The average change in weight across the entire study population was 1.80 ± 9.00%, representing ~0.448 ± 2.98 kg/m². Patients with pronounced weight loss had the highest risk of all-cause mortality (hazard ratio (HR) 2.07, 95% confidence interval (CI): 1.68-2.55), followed by patients with pronounced weight gain (HR 1.23, 95% CI: 1.02-1.56); patients with stable weight had the lowest risk. An asymmetric V-shaped relationship was observed between changes in BMI and all-cause mortality and non-cardiac mortality. Although no statistical significance was observed in terms of cardiac death and non-fatal MI, a flat V-shaped relationship may exist.

CONCLUSIONS

Weight was stable in most T2DM patients with high risk of CVD. Weight loss and gain is associated with increased all-cause mortality and non-cardiac mortality. Pronounced weight loss and weight gain is associated with a slight increase in cardiac death and non-fatal MI incidence, which does not reach statistical significance.

Changes in body mass index and mid-upper arm circumference in relation to all-cause mortality in older adults

BACKGROUND & AIMS

The assessment of weight loss as an indicator of poor nutritional status in older persons is currently widely applied to establish risk of mortality. Little is known about the relationship between changes in mid-upper arm circumference (MUAC) and mortality in older individuals. The aim of the present study was to examine the association between 3-year change in MUAC and 20-year mortality in community-dwelling older adults and compare this to the association between body mass index (BMI) change and mortality.

METHODS

Data on changes in MUAC (cm) and BMI (kg/m²), covariates, and mortality were available for 1307 Dutch older adults (49.7% men) aged 65 years and older in 1995/96 (mean 75.6 years, SD 6.5) from Longitudinal Aging Study Amsterdam (LASA). Anthropometric measurements were performed in 1992/93 with repeated measurements in 1995/96 (baseline), and a mortality follow up until July 2015. BMI and MUAC change were divided into quintiles, with the quintile including zero defined as the reference category. Cox regression analyses were performed to examine the associations of 3-year changes in MUAC and BMI with subsequent 20-year all-cause mortality, adjusted for demographic and health factors. Age, sex and initial measurement of BMI and MUAC (1992/93) were tested for effect modification (P = <0.10).

RESULTS

Mean baseline BMI was 26.7 kg/m² (SD 4.2) with a 3-year change of -0.2 (SD 1.5). Mean baseline MUAC was 30.5 cm (SD 3.5) with a 3-year change of -0.8 (SD 1.6). Age, sex, and BMI and MUAC 3 years prior were effect modifiers in the associations between change in anthropometric measurement and mortality. Decrease in MUAC was not associated with mortality in persons with a higher initial MUAC (≥31 cm), while for persons with a lower initial MUAC, a decrease in MUAC of ≤-2.15 was associated with increased mortality risk (HR 1.54; 95% CI: 1.14-2.09), also when further stratified on median age and sex. In stratified analysis of BMI change for median initial BMI (26.5) and additionally stratified for median age and sex, the associations between a BMI decrease of ≤-1.19 and mortality fluctuated, mostly statistically not significant. No associations were found for gain in MUAC or BMI.

CONCLUSIONS

Given that MUAC loss is more strongly and consistently associated with an increased mortality risk in older individuals with a low initial MUAC compared to BMI loss, this may be a more recommendable measure to use in clinical practice for assessing poor nutritional status, instead of weight loss.

Change in Weight and Body Mass Index Associated With All-Cause Mortality in Korea: A Nationwide Longitudinal Study

CONTEXT

Many studies have reported conflicting evidence on the association between weight change and mortality.

OBJECTIVE

We investigated the association between weight change and subsequent all-cause mortality, using a large-scale, population-based cohort from the National Health Insurance System health checkup data between 2005 and 2015.

METHODS

A total of 11,524,763 subjects older than age 20 years were included. Weight was measured every 2 years and weight change over 4 years was divided into eight categories, from weight loss ≥15% to weight gain ≥20%, for every 5% of weight change. The hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were analyzed using multivariable Cox proportional hazard models compared with the stable weight group (weight change <5%) after adjusting for age, sex, smoking, drinking, exercise, diabetes mellitus, hypertension, dyslipidemia, cancer, and income.

RESULTS

Weight loss was associated with increased mortality rates compared with weight gain; the group with weight loss ≥15% had the highest HR for all-cause mortality (HR, 2.598; 95% CI, 2.537 to 2.659). The HR for all-cause mortality in the ≥20% weight gain group was 1.784 (95% CI, 1.695 to 1.877). Across all body mass index (BMI) categories, weight loss ≥15% was associated with increased mortality rates and the highest mortality rates were found in the BMI ≥30 kg/m2 group (HR, 3.469; 95% CI, 2.236 to 5.381).

CONCLUSIONS

Weight change over 4 years showed a reverse J-shaped all-cause mortality curve, independent of BMI status. Weight loss was associated with a greater risk of mortality than was weight gain.

Influence of mealtime habits on the risk of weight gain and obesity in Mexican adults

OBJECTIVE

To prospectively examine the extent to which mealtime habits influences the risk of weight gain and obesity in Mexican adults.

DESIGN

We performed a prospective cohort study. The Mealtime Habits Quality (MHQ) scale was used for assessing participants' MHQ; the outcomes of interest were gain ≥5 % of body weight, developing overweight/obesity and abdominal obesity, after 7 years of follow-up. In order to estimate the independent effect of MHQ on anthropometric indicators, generalized linear models were computed to obtain adjusted relative risks (95 % CI).

SETTING

The state of Morelos, Mexico.

SUBJECTS

Mexican adults (n 837) aged 18-70 years participating in a cohort study.

RESULTS

Compared with participants classified in the higher MHQ category, individuals in the middle and lower MHQ groups had a 4·1 (2·5, 6·7) and 6·2 (3·9, 9·7) fold greater risk of gain ≥5 % of body weight, respectively; 6·6 (2·8, 15·5) and 8·6 (3·7, 19·8) fold greater risk of becoming overweight/obese, respectively; and 3·8 (2·0, 7·3) and 5·3 (2·8, 9·8) fold greater risk of developing abdominal obesity, respectively.

CONCLUSIONS

This study provides evidence about the influence of a set of mealtime habits on obesity indicators, showing that greater adherence to unadvisable mealtime habits increases the risk of developing unhealthy anthropometric indicators. Since the meal is one of the most important sources of food intake, and consequently weight status, the MHQ scale can be a useful population tool to predict weight gain and obesity.

BMI and all cause mortality: systematic review and non-linear dose-response meta-analysis of 230 cohort studies with 3.74 million deaths among 30.3 million participants

OBJECTIVE

To conduct a systematic review and meta-analysis of cohort studies of body mass index (BMI) and the risk of all cause mortality, and to clarify the shape and the nadir of the dose-response curve, and the influence on the results of confounding from smoking, weight loss associated with disease, and preclinical disease.

DATA SOURCES

PubMed and Embase databases searched up to 23 September 2015.

STUDY SELECTION

Cohort studies that reported adjusted risk estimates for at least three categories of BMI in relation to all cause mortality.

DATA SYNTHESIS

Summary relative risks were calculated with random effects models. Non-linear associations were explored with fractional polynomial models.

RESULTS

230 cohort studies (207 publications) were included. The analysis of never smokers included 53 cohort studies (44 risk estimates) with >738 144 deaths and >9 976 077 participants. The analysis of all participants included 228 cohort studies (198 risk estimates) with >3 744 722 deaths among 30 233 329 participants. The summary relative risk for a 5 unit increment in BMI was 1.18 (95% confidence interval 1.15 to 1.21; I(2)=95%, n=44) among never smokers, 1.21 (1.18 to 1.25; I(2)=93%, n=25) among healthy never smokers, 1.27 (1.21 to 1.33; I(2)=89%, n=11) among healthy never smokers with exclusion of early follow-up, and 1.05 (1.04 to 1.07; I(2)=97%, n=198) among all participants. There was a J shaped dose-response relation in never smokers (Pnon-linearity <0.001), and the lowest risk was observed at BMI 23-24 in never smokers, 22-23 in healthy never smokers, and 20-22 in studies of never smokers with ≥20 years' follow-up. In contrast there was a U shaped association between BMI and mortality in analyses with a greater potential for bias including all participants, current, former, or ever smokers, and in studies with a short duration of follow-up (<5 years or <10 years), or with moderate study quality scores.

CONCLUSION

Overweight and obesity is associated with increased risk of all cause mortality and the nadir of the curve was observed at BMI 23-24 among never smokers, 22-23 among healthy never smokers, and 20-22 with longer durations of follow-up. The increased risk of mortality observed in underweight people could at least partly be caused by residual confounding from prediagnostic disease. Lack of exclusion of ever smokers, people with prevalent and preclinical disease, and early follow-up could bias the results towards a more U shaped association.

Trajectories of Body Mass Index and Their Associations With Mortality Among Older Japanese: Do They Differ From Those of Western Populations?

Few studies have focused on the relationship between the trajectories of long-term changes in body mass index (BMI; weight (kg)/height (m)(2)) and all-cause mortality in old age, particularly in non-Western populations. We evaluated this association by applying group-based mixture models to data derived from the National Survey of the Japanese Elderly, which included 4,869 adults aged 60 or more years, with up to 7 repeated observations between 1987 and 2006. Four distinct BMI trajectories were identified: "low-normal weight, decreasing" (baseline BMI = 18.7; 23.8% of sample); "mid-normal weight, decreasing" (baseline BMI = 21.9; 44.6% of sample); "high-normal weight, decreasing" (baseline BMI = 24.8; 26.5% of sample); and "overweight, stable" (baseline BMI = 28.7; 5.2% of sample). Survival analysis with an average follow-up of 13.8 years showed that trajectories of higher BMI were associated with lower mortality. In particular, relative to those with a mid-normal weight, decreasing BMI trajectory, those with an overweight, stable BMI trajectory had the lowest mortality, and those with a low-normal, decreasing BMI trajectory had the highest mortality. In sharp contrast with prior observations from Western populations, BMI changes lie primarily within the normal-weight range, and virtually no older Japanese are obese. The association between BMI trajectories and mortality varies according to the distribution of BMI within the population.

Weight loss and premature death: the 1946 British birth cohort study

Objective

The relationship between weight loss and mortality has important clinical and public health significance but has proved to be complex. Evidence is mixed and particularly limited on the association between weight loss in mid-life and premature death (i.e. before 65 years of age), a small albeit important segment of total mortality. We aimed to study the association between midlife weight change and mortality accounting for health and lifestyle characteristics, and also considering potential bias due to preexisting chronic diseases and smoking status.

Design

Longitudinal, population-based, ‘the 1946 British’ birth cohort study.

Subjects and Measures

In 2750 men and women, mortality from age 53 through 65 years was analyzed according to categories of measured 10 year weight change between 43 and 53 years. Cox's hazard ratios (HR) were progressively adjusted for socio-demographic, lifestyle and health characteristics.

Results

Nearly 20% of participants lost weight and over 50% gained 5 kg or more in midlife. There were 164 deaths. Compared to those who gained between 2 and 5 kg, those who lost 5 kg or more had an increased risk of premature death independently of midlife physical activity, socio-economic circumstances and educational attainment. This association was unaltered when highest weight loss (lost more than 15 Kg) (p = 0.04) and early deaths were excluded (p<0.001), but was no longer significant after adjustment for cardiovascular risk factors and health status (HR = 1.8; 95% CI: 0.9 to 3.5).

Conclusion

The inverse association between weight loss in midlife and higher risk of premature death may be explained by vascular risk factors and ill health. In consideration of the burden of premature death, closer monitoring of weight loss in mid-life is warranted.

Body mass and weight change in adults in relation to mortality risk

Using data from the National Institutes of Health-AARP Diet and Health Study, we evaluated the influence of adulthood weight history on mortality risk. The National Institutes of Health-AARP Diet and Health Study is an observational cohort study of US men and women who were aged 50-71 years at entry in 1995-1996. This analysis focused on 109,947 subjects who had never smoked and were younger than age 70 years. We estimated hazard ratios of total and cause-specific mortality for recalled body mass index (BMI; weight (kg)/height (m)(2)) at ages 18, 35, and 50 years; weight change across 3 adult age intervals; and the effect of first attaining an elevated BMI at 4 successive ages. During 12.5 years' follow-up through 2009, 12,017 deaths occurred. BMI at all ages was positively related to mortality. Weight gain was positively related to mortality, with stronger associations for gain between ages 18 and 35 years and ages 35 and 50 years than between ages 50 and 69 years. Mortality risks were higher in persons who attained or exceeded a BMI of 25.0 at a younger age than in persons who reached that threshold later in adulthood, and risks were lowest in persons who maintained a BMI below 25.0. Heavier initial BMI and weight gain in early to middle adulthood strongly predicted mortality risk in persons aged 50-69 years.

Obesity and mortality risk: new findings from body mass index trajectories

Little research has addressed the heterogeneity and mortality risk in body mass index (BMI) trajectories among older populations. Applying latent class trajectory models to 9,538 adults aged 51 to 77 years from the US Health and Retirement Study (1992-2008), we defined 6 latent BMI trajectories: normal weight downward, normal weight upward, overweight stable, overweight obesity, class I obese upward, and class II/III obese upward. Using survival analysis, we found that people in the overweight stable trajectory had the highest survival rate, followed by those in the overweight obesity, normal weight upward, class I obese upward, normal weight downward, and class II/III obese upward trajectories. The results were robust after controlling for baseline demographic and socioeconomic characteristics, smoking status, limitations in activities of daily living, a wide range of chronic illnesses, and self-rated health. Further analysis suggested that BMI trajectories were more predictive of mortality risk than was static BMI status. Using attributable risk analysis, we found that approximately 7.2% of deaths after 51 years of age among the 1931-1941 birth cohort were due to class I and class II/III obese upward trajectories. This suggests that trajectories of increasing obesity past 51 years of age pose a substantive threat to future gains in life expectancy.

Factors associated with long-term weight loss and weight maintenance: analysis of a comprehensive workplace wellness program

OBJECTIVE

To examine factors associated with long-term weight loss and maintenance for participants of a comprehensive workplace wellness program.

METHODS

Data came from Health Risk Assessments completed by 89,746 overweight and obese persons between 2005 and 2010 to examine the association between demographics, improved nutrition, improved exercise and reduced stress and odds of weight loss and weight maintenance, as well as changes in bodyweight at 1 year follow-up. Generalized estimating equations were used to estimate coefficients of interest while controlling for confounds.

RESULTS

Factors significantly associated with increased odds and amount of weight loss were male gender, older age, reduced psychosocial stress, improved nutrition, and increased exercise when combined with improved nutrition.

CONCLUSIONS

Comprehensive workplace wellness programs that address weight management through an integrated stress management approach can be effective in addressing the obesity epidemic.

Age of 40 years or younger is an independent risk factor for locoregional failure in early breast cancer: a single-institutional analysis in saudi arabia

Background. This study was undertaken to evaluate the impact of prognostic factors on the locoregional failure-free survival of early breast cancer patients. Methods. In this single-institutional study, 213 breast cancer patients were retrospectively analysed. Fifty-five of 213 patients were ≤40 years of age at diagnosis. The impact of patient- or treatment-related factors on the locoregional failure-free survival was assessed using the Kaplan-Meier method. The simultaneous impact of factors on the locoregional failure-free survival was assessed using the Cox proportional hazards regression analysis. Results. The median follow-up time of the censored patients was 22 months (mean 28 months, range 3-92 months). On univariate analysis, statistically significant factors for the locoregional failure-free survival were the age (≤40 versus >40 years), T stage (Tis, T0-2 versus T3-4), molecular tumor type (luminal A versus luminal B, Her2neu overexpression, or triple negative), and lymphovascular status (LV0 versus LV1). On multivariate analysis, age and T stage remained statistically significant. Conclusions. Being 40 years or younger has a statistically significant independent adverse impact on the locoregional failure-free survival of patients with early breast cancer.

Inverse associations between long-term weight change and serum concentrations of persistent organic pollutants

There is emerging evidence that persistent organic pollutants (POPs) can increase the risk of various chronic diseases. As POPs mainly bioaccumulate in adipose tissue, weight change can affect serum concentrations of POPs. However, there are few population-based studies on effects of long-term weight change on serum concentrations of POPs. We examined associations between self-reported weight change over 1 year and 10 years and serum concentrations of seven POPs in 1099 adults aged ≥ 40. Serum concentrations of most POPs were higher in those with long-term weight loss, whereas they were lower in those with long-term weight gain. Adjusted correlation coefficients of each POP with weight change for 10 years were -0.23 (P < 0.01) for trans-nonachlor, -0.16 (P < 0.01) for p,p'-dichlorodiphenyldichloroethylene, and -0.21 (P < 0.01) for β-hexachlorocyclohexane, -0.16 (P < 0.01) for PCB169, -0.20 (P < 0.01) for PCB180 and -0.17 (P < 0.01) for 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin. Weight change for 1 year showed similar but weaker associations, compared with those of long-term weight changes. Although both beneficial health effects after weight loss and harmful health effects after weight gain are generally expected, changes in serum concentrations of POPs in relation to weight change may act on health in directions opposite to what we expect with weight change.

Weight change in later life and risk of death amongst the elderly: the European Prospective Investigation into Cancer and Nutrition-Elderly Network on Ageing and Health study

OBJECTIVE

Later life weight change and mortality amongst elders.

DESIGN

Nested case-control study.

SETTING

Six countries from the European Investigation into Cancer and nutrition-Elderly, Network on Ageing and Health.

SUBJECTS

A total of 1712 deceased (cases) and 4942 alive (controls) were selected from 34,239 participants, > or = 60 years at enrolment (1992-2000) who were followed-up until March 2007. Annual weight change was estimated as the weight difference from recruitment to the most distant from-date-of-death re-assessment, divided by the respective time.

OUTCOME MEASURES

Mortality in relation to weight change was examined using conditional logistic regression.

RESULTS

Weight loss > 1 kg year(-1) was associated with statistically significant increased death risk (OR = 1.65; 95% CI: 1.41-1.92) compared to minimal weight change (+/-1 kg year(-1)). Weight gain > 1 kg year(-1) was also associated with increased risk of death (OR = 1.15; 95% CI: 0.98-1.37), but this was evident and statistically significant only amongst overweight/obese (OR = 1.55; 95% CI: 1.17-2.05). In analyses by time interval since weight re-assessment, the association of mortality with weight loss was stronger for the interval proximal (< 1 year) to death (OR = 3.10; 95% CI: 2.03-4.72). The association of mortality with weight gain was stronger at the interval of more than 3 years and statistically significant only amongst overweight/obese (OR = 1.58; 95% CI: 1.07-2.33). Similar patterns were observed regarding death from circulatory diseases and cancer.

CONCLUSIONS

In elderly, stable body weight is a predictor of lower subsequent mortality. Weight loss is associated with increased mortality, particularly short-term, probably reflecting underlying nosology. Weight gain, especially amongst overweight/obese elders, is also associated with increased mortality, particularly longer term.

Factors in selecting the optimal bariatric procedure for a specific patient and parameters by which to measure appropriate response to surgery

Bariatric operations are increasingly being used to induce weight loss and ameliorate or cure most of the morbidities that accompany obesity. These procedures not only produce substantial weight loss (>50% body weight), but they cure or ameliorate the comorbidities (diabetes type 2, hypertension, sleep apnea, hyperlipidemia) in the vast majority of patients. These procedures can usually be performed laparoscopically with a mortality of less than 0.5% and a hospital stay of 1 to 3 days. Presently they are the only effective treatment for weight loss in the extremely obese patient (body mass index >/= 35).

Differential associations of weight dynamics with coronary artery calcium versus common carotid artery intima-media thickness: The CARDIA Study

Change and fluctuation in body mass index (BMI; weight (kg)/height (m)(2)) may be associated differently with coronary artery calcification (CAC) than with carotid artery intima-media thickness (IMT). The authors analyzed data on 2,243 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, initially aged 18-30 years, who were examined every 2-5 years over a 20-year period (1985-2006). BMI at year 0 was associated positively and linearly with CAC at year 20; however, the association of BMI with year 20 CAC became progressively U-shaped in subsequent examinations (years 10, 15, and 20). To understand the deepening U shape, the authors modeled year 20 BMI and its history using 3 indices: year 0 BMI, linear slope of BMI during 20 years, and BMI fluctuation during 20 years. In models including these 3 terms, year 0 BMI was associated positively with CAC, as was BMI fluctuation. However, adjusted odds ratios across quintiles of BMI slope (vs. the lowest quintile) were 0.7, 0.4, 0.5, and 0.4 (P(trend) < 0.01), suggesting higher risk of CAC with weight loss, plateauing after moderate weight gain. In contrast, IMT was associated positively with BMI at all examinations and with 20-year BMI slope and was unassociated with BMI fluctuation. Surprisingly, CAC risk was higher with BMI loss and lower with BMI gain, whereas associations with IMT were as expected.

Weight loss and mortality: a gender-specific analysis of the Tromsø study

BACKGROUND

Weight loss has been associated with increased mortality, but findings have been inconsistent.

OBJECTIVE

The aim of this study was to examine the association between weight loss and mortality, with a focus on gender differences.

METHODS

This was a population-based cohort study in northern Norway of adults, aged 20 to 54 years in 1979, who participated in 2 or 3 consecutive health surveys in 1979-80, 1986-87, and 1994-95. Weight and height were measured at each survey. The Cox proportional hazards regression model was used to estimate hazard ratios for mortality between levels of body mass index (BMI) change during 11 years of follow-up. Participants with prior cardiovascular disease or cancer, or incident cancer within the first 2 years of follow-up, were excluded, as were participants who were pregnant, had missing data, or did not give written consent.

RESULTS

A total of 4881 men and 5051 women participated in the present study. The mean age at start of follow-up was 50.8 years (range, 35-70 years) in men and 49.2 years (range, 35-65 years) in women. In men, weight loss was associated with increased all-cause, cardiovascular, and noncardiovascular mortality. The hazard ratio for men for all-cause mortality with a 10-year BMI decrease of 2 kg/m(2) versus a BMI increase of 1 kg/m(2) was 2.09 (95% CI, 1.56-2.81). The association was not significantly modified by initial BMI, age, smoking status, or self-reported attempts of weight loss, or by exclusion of subjects with self-reported poor health, diabetes mellitus, high blood pressure, or high alcohol intake. In women, no association between BMI change and mortality was observed. However, in the subgroup of women who reported no weight-loss attempts, BMI change was significantly associated with mortality risk (P = 0.022).

CONCLUSIONS

In this study of a Norwegian population, weight loss was associated with excess mortality in men in all subgroups of weight-loss attempts, daily smoking, and overweight. In women, the only significant effect of BMI change on mortality was observed in those who reported no weight-loss attempts. The observed findings could not be explained by preexisting disease.

Minimal limb volume change has a significant impact on breast cancer survivors

We sought to define the incidence, risk factors, symptoms, and quality of life (QOL) outcomes associated with various degrees of postoperative limb volume change (LVC). A prospective cohort study was performed obtaining serial limb volume measurements using a perometer on 269 women undergoing surgery for breast cancer. Four groups were created based on maximum LVC: none < 5.0%, mild 5.0-9.9%, moderate 10.0-14.9%, and severe 15.0%. Symptoms and QOL were assessed. 81 (30.1%), 70 (26.0%), and 14 (5.2%) women developed mild, moderate, and severe LVC, respectively. Increases in body mass index (p < 0.001) and post-operative complications (p = 0.002) were associated with increasing LVC. Lower QOL scores were associated with a moderate LVC (OR = 3.72, 95% CI, 1.29-10.73, p = 0.015) and postoperative infections (OR = 5.04, 95% CI, 1.73-14.70, p = 0.003). LVC at 5.0% occurs in up to 61.3% of breast cancer survivors and is associated with a significant increase in symptoms and a change in reported quality of life.

A review and meta-analysis of the effect of weight loss on all-cause mortality risk

Overweight and obesity are associated with increased morbidity and mortality, although the range of body weights that is optimal for health is controversial. It is less clear whether weight loss benefits longevity and hence whether weight reduction is justified as a prime goal for all individuals who are overweight (normally defined as BMI>25 kg/m2). The purpose of the present review was to examine the evidence base for recommending weight loss by diet and lifestyle change as a means of prolonging life. An electronic search identified twenty-six eligible prospective studies that monitored subsequent mortality risk following weight loss by lifestyle change, published up to 2008. Data were extracted and further analysed by meta-analysis, giving particular attention to the influence of confounders. Moderator variables such as reason for weight loss (intentional, unintentional), baseline health status (healthy, unhealthy), baseline BMI (normal, overweight, obese), method used to estimate weight loss (measured weight loss, reported weight loss) and whether models adjusted for physical activity (adjusted data, unadjusted data) were used to classify subgroups for separate analysis. Intentional weight loss per se had a neutral effect on all-cause mortality (relative risk (RR) 1·01; P = 0·89), while weight loss which was unintentional or ill-defined was associated with excess risk of 22 to 39 %. Intentional weight loss had a small benefit for individuals classified as unhealthy (with obesity-related risk factors) (RR 0·87 (95 % CI 0·77, 0·99); P = 0·028), especially unhealthy obese (RR 0·84 (95 % CI 0·73, 0·97); P = 0·018), but appeared to be associated with slightly increased mortality for healthy individuals (RR 1·11 (95 % CI 1·00, 1·22); P = 0·05), and for those who were overweight but not obese (RR 1·09 (95 % CI 1·02, 1·17); P = 0·008). There was no evidence for weight loss conferring either benefit or risk among healthy obese. In conclusion, the available evidence does not support solely advising overweight or obese individuals who are otherwise healthy to lose weight as a means of prolonging life. Other aspects of a healthy lifestyle, especially exercise and dietary quality, should be considered. However, well-designed intervention studies are needed clearly to disentangle the influence of physical activity, diet strategy and body composition, in order to define appropriate advice to those populations that might be expected to benefit.

Long-term weight loss effects on all cause mortality in overweight/obese populations

This systematic review assesses the long-term effectiveness of weight loss on all cause mortality in overweight/obese people. Medline, Embase and Cinahl were searched (1966-2005). Cohort studies and trials on participants with body mass index > or =25 kg m(-2), with weight change and mortality with > or =2-year follow-up, were included finally identifying 11 papers based on eight studies. There may be gender differences in the benefits for all cause mortality. The impact of weight loss in men on mortality was not clear with some studies indicating weight loss to be detrimental, while a recent cohort study showed benefits, if it were a personal decision. Other studies with no gender separation had similarly mixed results. However, one study indicated that overweight/obese women with obesity-related illness, who lost weight intentionally within 1 year, had significantly reduced mortality rates of 19-25%. In contrast, studies of overweight/obese diabetics irrespective of gender showed significant benefit of intentional weight loss on mortality in a meta-analysis, hazard ratios = 0.75 (0.67-0.83). There is some evidence that intentional weight loss has long-term benefits on all cause mortality for women and more so for diabetics. Long-term effects especially for men are not clear and need further investigation.

Quality of Life as a Predictor of Weight Loss in Obese, Early-Stage Breast Cancer Survivors

PURPOSE/OBJECTIVES

To investigate whether quality of life (QOL) assessed before weight loss intervention predicts weight loss and, in turn, what the effect of weight loss is on QOL measures after 12 months in early-stage breast cancer survivors.

DESIGN

A clinical trial of a weight loss intervention in breast cancer survivors.

SETTING

Community-wide recruitment in Detroit, MI.

SAMPLE

39 breast cancer survivors (body mass index = 30-44 kg/m2), within three years of initial diagnosis and at least three months after chemotherapy or radiation therapy.

METHODS

Participants were randomized to one of three weight loss methods or a control group. The Functional Assessment of Cancer Therapy-Anemia (FACT-An) QOL questionnaire was administered at baseline and after the intervention.

MAIN RESEARCH VARIABLES

Six subscales of the FACT-An and weight change.

FINDINGS

Modest but statistically significant associations were found for the physical and functional subscales of the FACT-An with weight loss for 39 subjects who completed 12 months of the study. Those reporting relatively impaired physical or functional QOL at baseline lost more weight, which accounted for 8%-9% of the weight loss variance beyond that resulting from the diet arm assignment. At 12 months, greater weight loss was associated with significant improvements in overall FACT-An score and in the physical, functional, fatigue, and anemia subscales (p < 0.05).

CONCLUSIONS

Relatively low physical function at baseline was not a barrier to weight loss; indeed, it may have been a motivating factor in adherence to the weight loss intervention. Weight loss was associated with improvement in several QOL subscale measures in breast cancer survivors, but the emotional and social subscales were not affected.

IMPLICATIONS FOR NURSING

Counseling for weight loss that includes recommendations for exercise should not be withheld for patients with relatively low physical functioning.

Nine-year changes in cardiovascular disease risk factors with weight maintenance in the atherosclerosis risk in communities cohort

Few studies have focused on the impact of weight maintenance on cardiovascular disease risk factors or addressed whether changes differ by baseline weight status and medication usage. The authors examined these issues using 9 years of follow-up data on 3,235 men and women from the Atherosclerosis Risk in Communities (ARIC) Study who were aged 45-64 years at baseline (1987-1989). In participants not using medications, glucose (3.0 mg/dl, 95% confidence interval (CI): 2.4, 3.5) and triglycerides (10.1 mg/dl, 95% CI: 8.3, 11.9) increased, while total cholesterol (-9.6 mg/dl, 95% CI: -10.6, -8.6), low density lipoprotein cholesterol (-9.9 mg/dl, 95% CI: -10.9, -9.0), and high density lipoprotein cholesterol (-1.7 mg/dl, 95% CI: -2.1, -1.3) decreased. Systolic blood pressure (7.9 mmHg, 95% CI: 7.3, 8.4) increased, but diastolic blood pressure (-1.1 mmHg, 95% CI: -1.4, -0.7) declined. Normal weight (body mass index: 18.5-<25.0 kg/m(2)) participants had smaller increases in glucose compared with obese (body mass index: >/=30.0 kg/m(2)) participants. In contrast, the authors found less favorable changes in total, low density lipoprotein, and high density lipoprotein cholesterol, triglycerides, and diastolic blood pressure among normal weight compared with obese participants who maintained their weight. These patterns were similar across weight status groups regardless of medication usage.

Obesity and prognosis of breast cancer

Obesity has a complicated relationship to both breast cancer risk and the clinical behaviour of the established disease. It is suggested that obesity is associated with both an increased risk of developing breast cancer risk and worse prognosis after disease onset. In post-menopausal women, various measures of obesity such as body mass index, weight, weight gain and waist : hip ratio have all been positively associated with risk of developing breast cancer. In most but not all case-control and prospective cohort studies, an inverse relationship has been found between weight and breast cancer among pre-menopausal women. Some data suggest that adult weight gain and central obesity increase the risk of pre-menopausal breast cancer. Obesity at the time of diagnosis is thought to be significant as a poor prognostic factor. Obesity is associated with adverse outcomes in both pre- and post-menopausal women with breast cancer. Many cancer survivors seek ways to minimize the risk of recurrence and death because of breast cancer. Despite complex and at times controversial data, enough evidence is available at present to suggest that weight management should be a part of the strategy to prevent the occurrence, recurrence and death because of breast cancer. In this review the effect of obesity on the prognosis of breast cancer is examined in detail.

Association of body mass index and weight change with all-cause mortality in the elderly

The authors explored the relation of body mass index (BMI; weight (kg)/height (m)(2)) and weight change to all-cause mortality in the elderly, using data from a large, population-based California cohort study, the Leisure World Cohort Study. They estimated relative risks of mortality associated with self-reported BMI at study entry, BMI at age 21 years, and weight change between age 21 and study entry. Participants were categorized as underweight (BMI <18.5), normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9), or obese (BMI >or=30). Of 13,451 participants aged 73 years (on average) at study entry (1981-1985), 11,203 died during 23 years of follow-up (1981-2004). Relative to normal weight, being underweight (relative risk (RR) = 1.51, 95% confidence interval (CI): 1.38, 1.65) or obese (RR = 1.25, 95% CI: 1.13, 1.38) at study entry was associated with increased mortality. People who were either overweight or obese at age 21 also had increased mortality (RR = 1.17, 95% CI: 1.09, 1.25). Participants who lost weight between age 21 and study entry had increased mortality regardless of their BMI category at age 21. Obesity was significantly associated with increased mortality only among persons under age 75 years and among never or past smokers. This study highlights the influence on older-age mortality risk of being overweight or obese in young adulthood and underweight or obese in later life.

Heart Disease Risk Determines Menopausal Age Rather Than the Reverse

OBJECTIVES

The purpose of this study was to investigate whether a harmful cardiovascular risk profile accelerates menopause.

BACKGROUND

Women with an early menopause are at an increased risk of cardiovascular disease. Although increased cardiovascular risk has been proposed as consequence of menopause, the alternative hypothesis, that increased premenopausal cardiovascular risk promotes early menopause, needs to be examined.

METHODS

We used data from the Framingham Heart Study cohort. This study started in 1948 and has followed up participants biennially since then. Women who were premenopausal at study entry and who reached natural menopause after at least two examination rounds were included in the study (n = 695). Premenopausal age-independent levels of serum total cholesterol, relative weight, blood pressure, and Framingham risk score were determined, as well as premenopausal changes in cholesterol, body weight, and blood pressure.

RESULTS

A higher premenopausal serum total cholesterol level was statistically significantly associated with an earlier age at menopause, as were increases in total serum cholesterol, relative weight, and blood pressure in the premenopausal period. A decrease in total serum cholesterol during premenopause was statistically significantly associated with later age at menopause. Decreasing blood pressure was associated with a later menopausal age, but this association was not statistically significant. A decrease in relative weight was associated with a significant earlier age at menopause. Each 1% higher premenopausal Framingham risk score was associated with a decrease in menopausal age of 1.8 years (95% confidence interval -2.72 to -0.92).

CONCLUSIONS

The findings support the view that heart disease risk determines age at menopause. This offers a novel explanation for the inconsistent findings on cardiovascular disease rate and its relationship to menopausal age and effects of hormone replacement therapy.

The definition of weight maintenance

There is currently no consensus on the definition of weight maintenance in adults. Issues to consider in setting a standard definition include expert opinion, precedents set in previous studies, public health and clinical applications, comparability across body sizes, measurement error, normal weight fluctuations and biologic relevance. To be useful, this definition should indicate an amount of change less than is clinically relevant, but more than expected from measurement error or fluctuations in fluid balance under normal conditions. It is an advantage for the definition to be graded by body size and to be easily understood by the public as well as scientists. Taking all these factors into consideration, the authors recommend that long-term weight maintenance in adults be defined as a weight change of <3% of body weight.

Childhood IQ in relation to obesity and weight gain in adult life: the National Child Development (1958) Study

OBJECTIVE

To examine the relation of childhood intelligence (IQ) test results with obesity in middle age and weight gain across the life course.

METHODS

We analysed data from the National Child Development (1958) Study, a prospective cohort study of 17 414 births to parents residing in Great Britain in the late 1950s. Childhood IQ was measured at age 11 years and body mass index (BMI), an indicator of adiposity, was assessed at 16, 23, 33 and 42 years of age. Logistic regression (in which BMI was categorised into obese and non-obese) and structural equation growth curve models (in which BMI was retained as a continuous variable) were used to estimate the relation between childhood IQ and adult obesity, and childhood IQ and weight gain, respectively.

RESULTS

In unadjusted analyses, lower childhood IQ scores were associated with an increased prevalence of adult obesity at age 42 years. This relation was somewhat stronger in women (OR(per SD decrease in IQ score) [95% CI]: 1.38 [1.26, 1.50]) than men (1.26 [1.15, 1.38]). This association remains statistically significant after adjusting for childhood characteristics, including socio-economic factors, but was heavily attenuated following control for adult characteristics, particularly education (women: 1.11 [0.99, 1.25]; men: 1.10 [0.98, 1.23]). When weight gain between age 16 and 42 years was the outcome of interest, structural equation modelling revealed that education and dietary characteristics in adult life mediated the association with childhood IQ.

CONCLUSIONS

A lower IQ score in childhood is associated with obesity and weight gain in adulthood. In the present study, this relation appears to be largely mediated via educational attainment and the adoption of healthy diets in later life.

Increased exercise capacity after surgically induced weight loss in morbid obesity

OBJECTIVE

To investigate the effects of surgically induced weight loss on exercise capacity in patients with morbid obesity (MO).

RESEARCH METHODS AND PROCEDURES

A prospective 1-year follow-up study was carried out, with patients being their own controls. A symptom-limited cardiopulmonary exercise stress test was performed in 31 MO patients (BMI > 40 kg/m2) before and 1 year after undergoing bariatric surgery.

RESULTS

At 1 year after surgery, weight was reduced from 146 +/- 33 to 95 +/- 19 kg (p < 0.001), and BMI went from 51 +/- 4 to 33 +/- 6 kg/m2 (p < 0.001). After weight loss, obese patients performed each workload with lower oxygen consumption, heart rate, systolic arterial pressure, and ventilatory volume (p < 0.001). This reduced energy expenditure allowed them to increase the duration of their effort test from 13.8 +/- 3.8 to 21 +/- 4.2 minutes (p < 0.001). Upon finishing the exercise, MO patients before surgery were able to reach only 83% of their age-predicted maximal heart rate, and their respiratory exchange ratio was 0.87 +/- 0.06. After weight loss, those values were 90% and 1 +/- 0.08, respectively (p < 0.01). When we compared the peak O2 pulse corrected by fat free mass before and after surgery, no significant differences between the groups were found.

DISCUSSION

After surgically induced weight loss, MO patients markedly improved their exercise capacity. This is due to the fact that they were able to perform the external work with lower energy expenditure and also to increase cardiovascular stress, optimizing the use of cardiac reserve. There were no differences in cardiac function before and after surgery.

Weight change in adult life and health outcomes

OBJECTIVE

To investigate the relationship between weight change in adult life and subsequent mortality and cancer incidence in women.

RESEARCH METHODS AND PROCEDURES

In 1994 to 1995, all women (age range, 42 to 81) still under general practitioner observation in the United Kingdom's Royal College of General Practitioners Oral Contraception Study (n = 12,303) were sent a health survey asking about health and lifestyle issues, including current weight and weight at age 30. The main outcome measures were 6-year all-cause mortality and cancer incidence among different weight change deciles. Cox regression was used to calculate hazard ratios that were adjusted for: social class at recruitment, BMI at age 30, and age group, parity, smoking status, and hormone replacement therapy status in 1995.

RESULTS

Women who had been obese at age 30 were more likely to die and significantly more likely to develop cancer in the 6 years after the health survey than non-obese respondents. Women reporting weight gains between age 30 and 1995 were significantly less likely to die during the 6 years after the health survey than those with a stable weight, whereas those with weight loss did not fare any better than those in the stable-weight group.

DISCUSSION

Although obesity at young age was associated with subsequent mortality and cancer incidence, weight gain over a time period of 12 to 51 years appeared to be beneficial when compared with women with stable weight over the same time period. Further research is needed to confirm or refute our findings and to allow detailed examination of potential explanations for them.

Comparison of isocaloric very low carbohydrate/high saturated fat and high carbohydrate/low saturated fat diets on body composition and cardiovascular risk

Background

It is speculated that high saturated fat very low carbohydrate diets (VLCARB) have adverse effects on cardiovascular risk but evidence for this in controlled studies is lacking. The objective of this study was to compare, under isocaloric conditions, the effects of a VLCARB to 2 low saturated fat high carbohydrate diets on body composition and cardiovascular risk.

Methods

Eighty three subjects, 48 ± 8 y, total cholesterol 5.9 ± 1.0 mmol/L, BMI 33 ± 3 kg/m² were randomly allocated to one of 3 isocaloric weight loss diets (6 MJ) for 8 weeks and on the same diets in energy balance for 4 weeks: Very Low Fat (VLF) (CHO:Fat:Protein; %SF = 70:10:20; 3%), High Unsaturated Fat (HUF) = (50:30:20; 6%), VLCARB (4:61:35; 20%)

Results

Percent fat mass loss was not different between diets VLCARB -4.5 ± 0.5, VLF-4.0 ± 0.5, HUF -4.4 ± 0.6 kg). Lean mass loss was 32-31% on VLCARB and VLF compared to HUF (21%) (P < 0.05). LDL-C increased significantly only on VLCARB by 7% (p < 0.001 compared with the other diets) but apoB was unchanged on this diet and HDL-C increased relative to the other 2 diets. Triacylglycerol was lowered by 0.73 ± 0.12 mmol/L on VLCARB compared to -0.15 ± 0.07 mmol/L on HUF and -0.06 ± 0.13 mmol/L on VLF (P < 0.001). Plasma homocysteine increased 6.6% only on VLCARB (P = 0.026). VLCARB lowered fasting insulin 33% compared to a 19% fall on HUF and no change on VLF (P < 0.001). The VLCARB meal also provoked significantly lower post prandial glucose and insulin responses than the VLF and HUF meals. All diets decreased fasting glucose, blood pressure and CRP (P < 0.05).

Conclusion

Isocaloric VLCARB results in similar fat loss than diets low in saturated fat, but are more effective in improving triacylglycerols, HDL-C, fasting and post prandial glucose and insulin concentrations. VLCARB may be useful in the short-term management of subjects with insulin resistance and hypertriacylglycerolemia.

Factores sociodemográficos y de hábitos de vida asociados al cambio de peso en la población adulta de mayor edad en España

BACKGROUND AND OBJECTIVE

Our purpose was to examine sociodemographic factors and lifestyle customs associated with weight change in the older adult population of Spain.

SUBJECTS AND METHOD

Prospective cohort study conducted from 2001 to 2003 among a cohort of 2,384 people representative of the non-institutionalized Spanish population aged 60 years and over. Data were collected through home interviews, and main statistical analysis was performed through polytomous logistic regression.

RESULTS

Over the 2-year follow-up, 27.9% of men and 27.3% of women lost > or = 3 kg, and 18.2% of men and 16.9% of women gained > or = 3 kg. Among men, a loss of > or = 3 kg was more likely among former smokers (odds ratio [OR] = 1.58; 95% confidence interval [CI], 1.13-2.23) and among those with higher body mass index (BMI) (p for linear trend < 0.0001). A weight gain of > or = 3 kg was also more frequent in former smokers (OR = 1.93; 95% IC, 1.28-2.90). In addition, the risk of gaining > or = 3 kg decreased progressively with the increase in the frequency of physical activity at leisure time (p for linear trend < 0.0001). Among women, results were similar to those in men, though in former smokers there was no association with weight changes.

CONCLUSIONS

In the older adult population, BMI, physical activity at leisure time, and a former smoker status are associated with weight change in the short term. Intervention on physical activity should be a priority, because it is the main modifiable factor, is associated with health-related quality of life, and it could contribute to avoid excess weight.

Weight change and mortality: the Nord-Trøndelag Health Study

OBJECTIVES

The prevalence of obesity is increasing. Overweight and obese people have increased mortality compared with normal weight people. We investigated the effect of weight change on mortality.

DESIGN

Prospective population study.

SETTING

We utilized data from two large population-based health studies conducted in 1984-86 and 1995-97 respectively. Cox proportional hazards models were used to calculate mortality rate ratios (RRs) with 95% confidence intervals (CIs) between people with a stable weight and people who lost or gained weight. Subjects. Totally 20,542 men and 23,712 women aged 20 years or more, without cardiovascular disease or diabetes at the first survey and without a history of cancer at the second survey were followed up on all-cause mortality for 5 years after the second survey.

RESULTS

We found no association between weight gain and mortality. People who lost weight had a higher total mortality rate compared with those who were weight stable [RR was 1.6 (95% CI: 1.4-1.8) in men and 1.7 (95% CI: 1.5-2.0) in women]. Similar associations were found for cardiovascular and noncardiovascular mortality. Additional analysis showed a linear increase in mortality rates across categories of weight loss for both men and women (P < 0.001). There was a statistically significant interaction between weight change and initial BMI, but only amongst men (P = 0.001).

CONCLUSIONS

Weight loss, but not weight gain, was associated with increased mortality amongst men and women. Although underlying undiagnosed disease is the most plausible explanation for this finding, the similar associations found for total mortality, cardiovascular mortality, and noncardiovascular mortality makes the causal pathway somewhat enigmatic.