Diversity of plant DNA in stool is linked to dietary quality, age, and household income.

Eating a varied diet is a central tenet of good nutrition. Here, we develop a molecular tool to quantify human dietary plant diversity by applying DNA metabarcoding with the chloroplast trnL-P6 marker to 1,029 fecal samples from 324 participants across two interventional feeding studies and three observational cohorts. The number of plant taxa per sample (plant metabarcoding richness or pMR) correlated with recorded intakes in interventional diets and with indices calculated from a food frequency questionnaire in typical diets (ρ = 0.40 to 0.63). In adolescents unable to collect validated dietary survey data, trnL metabarcoding detected 111 plant taxa, with 86 consumed by more than one individual and four (wheat, chocolate, corn, and potato family) consumed by >70% of individuals. Adolescent pMR was associated with age and household income, replicating prior epidemiologic findings. Overall, trnL metabarcoding promises an objective and accurate measure of the number and types of plants consumed that is applicable to diverse human populations.

Frequency and Geographic Distribution of Borrelia miyamotoi, Borrelia burgdorferi, and Babesia microti Infections in New England Residents.

BACKGROUND: Borrelia miyamotoi is a relapsing fever spirochete that relatively recently has been reported to infect humans. It causes an acute undifferentiated febrile illness that can include meningoencephalitis and relapsing fever. Like Borrelia burgdorferi, it is transmitted by Ixodes scapularis ticks in the northeastern United States and by Ixodes pacificus ticks in the western United States. Despite reports of clinical cases from North America, Europe, and Asia, the prevalence, geographic range, and pattern of expansion of human B. miyamotoi infection are uncertain. To better understand these characteristics of B. miyamotoi in relation to other tickborne infections, we carried out a cross-sectional seroprevalence study across New England that surveyed B. miyamotoi, B. burgdorferi, and Babesia microti infections. METHODS: We measured specific antibodies against B. miyamotoi, B. burgdorferi, and B. microti among individuals living in 5 New England states in 2018. RESULTS: Analysis of 1153 serum samples collected at 11 catchment sites showed that the average seroprevalence for B. miyamotoi was 2.8% (range, 0.6%-5.2%), which was less than that of B. burgdorferi (11.0%; range, 6.8%-15.6%) and B. microti (10.0%; range, 6.5%-13.6%). Antibody screening within county residence in New England showed varying levels of seroprevalence for these pathogens but did not reveal a vectoral geographical pattern of distribution. CONCLUSIONS: Human infections caused by B. miyamotoi, B. burgdorferi, and B. microti are widespread with varying prevalence throughout New England.

Dietary patterns and associations with BMI in low-income, ethnic minority youth in the USA according to baseline data from four randomised controlled trials.

Few studies have derived data-driven dietary patterns in youth in the USA. This study examined data-driven dietary patterns and their associations with BMI measures in predominantly low-income, racial/ethnic minority US youth. Data were from baseline assessments of the four Childhood Obesity Prevention and Treatment Research (COPTR) Consortium trials: NET-Works (534 2-4-year-olds), GROW (610 3-5-year-olds), GOALS (241 7-11-year-olds) and IMPACT (360 10-13-year-olds). Weight and height were measured. Children/adult proxies completed three 24-h dietary recalls. Dietary patterns were derived for each site from twenty-four food/beverage groups using k-means cluster analysis. Multivariable linear regression models examined associations of dietary patterns with BMI and percentage of the 95th BMI percentile. Healthy (produce and whole grains) and Unhealthy (fried food, savoury snacks and desserts) patterns were found in NET-Works and GROW. GROW additionally had a dairy- and sugar-sweetened beverage-based pattern. GOALS had a similar Healthy pattern and a pattern resembling a traditional Mexican diet. Associations between dietary patterns and BMI were only observed in IMPACT. In IMPACT, youth in the Sandwich (cold cuts, refined grains, cheese and miscellaneous) compared with Mixed (whole grains and desserts) cluster had significantly higher BMI (ß = 0·99 (95 % CI 0·01, 1·97)) and percentage of the 95th BMI percentile (ß = 4·17 (95 % CI 0·11, 8·24)). Healthy and Unhealthy patterns were the most common dietary patterns in COPTR youth, but diets may differ according to age, race/ethnicity or geographic location. Public health messages focused on healthy dietary substitutions may help youth mimic a dietary pattern associated with lower BMI.

Obesogenic home food availability, diet, and BMI in Pakistani and White toddlers.

Individuals of South Asian ethnicity have an increased risk for obesity and related diseases. Foods available in the home during the first 1000 days (conception to 24 months old) are an important determinant of diet, yet no study has examined the association of early-life home food availability (HFA) with later diet and obesity risk in South Asian households. We examined whether obesogenic HFA at 18 months of age is associated with dietary intake and body mass index (BMI) at 36 months of age in low-income Pakistani and White households in the United Kingdom. In this prospective birth cohort study (Born in Bradford 1000), follow-up assessments occurred at 18 (n = 1032) and 36 (n = 986) months of age. Variety and quantity of snack foods and sugar-sweetened beverages (SSBs) in the home and consumed were measured using the HFA Inventory Checklist and food frequency questionnaires, respectively. BMI was calculated using measured length/height and weight. Multinomial logistic regression models examined associations between HFA and tertiles of dietary intake, and multivariable linear regression models assessed associations between HFA and BMI. Pakistani households had a greater variety and quantity of snack foods and SSBs available compared with White households. Variety and quantity of snack foods and SSBs in the home at 18 months were positively associated with children's intake of these items at 36 months, but associations between HFA and BMI were null. Reducing obesogenic HFA during the first 1000 days may promote the development of more healthful diets, though this may not be associated with lower obesity risk during toddlerhood.

Measuring commissioners' willingness-to-pay for community based childhood obesity prevention programmes using a discrete choice experiment.

BACKGROUND: In the UK, rates of childhood obesity remain high. Community based programmes for child obesity prevention are available to be commissioned by local authorities. However, there is a lack of evidence regarding how programmes are commissioned and which attributes of programmes are valued most by commissioners. The aim of this study was to determine the factors that decision-makers prioritise when commissioning programmes that target childhood obesity prevention. METHODS: An online discrete choice experiment (DCE) was used to survey commissioners and decision makers in the UK to assess their willingness-to-pay for childhood obesity programmes. RESULTS: A total of 64 commissioners and other decision makers completed the DCE. The impact of programmes on behavioural outcomes was prioritised, with participants willing to pay an extra £16,600/year if average daily fruit and vegetable intake increased for each child by one additional portion. Participants also prioritised programmes that had greater number of parents fully completing them, and were willing to pay an extra £4810/year for every additional parent completing a programme. The number of parents enrolling in a programme (holding the number completing fixed) and hours of staff time required did not significantly influence choices. CONCLUSIONS: Emphasis on high programme completion rates and success increasing children's fruit and vegetable intake has potential to increase commissioning of community based obesity prevention programmes.

Genetic polymorphisms of diabetes-related genes, their interaction with diabetes status, and breast cancer incidence and mortality: The Long Island Breast Cancer Study Project.

To examine 143 diabetes risk single nucleotide polymorphisms (SNPs), identified from genome-wide association studies, in association with breast cancer (BC) incidence and subsequent mortality. A population-based sample of Caucasian women with first primary invasive BC (n = 817) and controls (n = 1021) were interviewed to assess diabetes status. Using the National Death Index, women with BC were followed for >18 years during which 340 deaths occurred (139 BC deaths). Genotyping was done using DNA extracted from blood samples. We used unconditional logistic regression to estimate age-adjusted odds ratios and 95% confidence intervals (CIs) for BC incidence, and Cox regression to estimate age-adjusted hazard ratios and CIs for all-cause and BC-specific mortality. Twelve SNPs were associated with BC risk in additive genotype models, at α = 0.05. The top three significant SNPs included SLC30A8-rs4876369 (P = 0.0034), HHEX-rs11187146 (P = 0.0086), and CDKN2A/CDKN2B-rs1333049 (P = 0.0094). Diabetes status modified the associations between rs4876369 and rs2241745 and BC incidence, on the multiplicative interaction scale. Six SNPs were associated with all-cause (CDKAL1-rs981042, P = 0.0032; HHEX-rs1111875, P = 0.0361; and INSR-rs919275, P = 0.0488) or BC-specific (CDKN2A/CDKN2B-rs3218020, P = 0.0225; CDKAL1-rs981042, P = 0.0246; and TCF2/HNF1B-rs3094508, P = 0.0344) mortality in additive genotype models, at α = 0.05. Genetic polymorphisms that increase the risk of developing diabetes may also increase the risk of developing and dying from BC.

Association of food parenting practice patterns with obesogenic dietary intake in Hispanic/Latino youth: Results from the Hispanic Community Children's Health Study/Study of Latino Youth (SOL Youth).

Some food parenting practices (FPPs) are associated with obesogenic dietary intake in non-Hispanic youth, but studies in Hispanics/Latinos are limited. We examined how FPPs relate to obesogenic dietary intake using cross-sectional data from 1214 Hispanic/Latino 8-16-year-olds and their parents/caregivers in the Hispanic Community Children's Health Study/Study of Latino Youth (SOL Youth). Diet was assessed with 2 24-h dietary recalls. Obesogenic items were snack foods, sweets, and high-sugar beverages. Three FPPs (Rules and Limits, Monitoring, and Pressure to Eat) derived from the Parenting strategies for Eating and Activity Scale (PEAS) were assessed. K-means cluster analysis identified 5 groups of parents with similar FPP scores. Survey-weighted multiple logistic regression examined associations of cluster membership with diet. Parents in the controlling (high scores for all FPPs) vs. indulgent (low scores for all FPPs) cluster had a 1.75 (95% CI: 1.02, 3.03) times higher odds of having children with high obesogenic dietary intake. Among parents of 12-16-year-olds, membership in the pressuring (high Pressure to Eat, low Rules and Limits and Monitoring scores) vs. indulgent cluster was associated with a 2.96 (95% CI: 1.51, 5.80) times greater odds of high obesogenic dietary intake. All other associations were null. Future longitudinal examinations of FPPs are needed to determine temporal associations with obesogenic dietary intake in Hispanic/Latino youth.

Multicomponent Obesity Prevention Intervention in Low-Income Preschoolers: Primary and Subgroup Analyses of the NET-Works Randomized Clinical Trial, 2012-2017.

OBJECTIVES: To evaluate a multicomponent obesity prevention intervention among diverse, low-income preschoolers. METHODS: Parent-child dyads (n = 534) were randomized to the Now Everybody Together for Amazing and Healthful Kids (NET-Works) intervention or usual care in Minneapolis, MN (2012-2017). The intervention consisted of home visits, parenting classes, and telephone check-ins. The primary outcomes were adjusted 24- and 36-month body mass index (BMI). RESULTS: Compared with usual care, the NET-Works intervention showed no significant difference in BMI change at 24 (-0.12 kg/m2; 95% confidence interval [CI] = -0.44, 0.19) or 36 months (-0.19 kg/m2; 95% CI = -0.64, 0.26). Energy intake was significantly lower in the NET-Works group at 24 (-90 kcal/day; 95% CI = -164, -16) and 36 months (-101 kcal/day; 95% CI = -164, -37). Television viewing was significantly lower in the NET-Works group at 24 (rate ratio = 0.84; 95% CI = 0.75, 0.93) and 36 months (rate ratio = 0.88; 95% CI = 0.78, 0.99). Children with baseline overweight or obesity had lower BMI in the NET-Works group than those in usual care at 36 months (-0.71 kg/m2; 95% CI = -1.30, -0.12). Hispanic children had lower BMI in the NET-Works group than those in usual care at 36 months (-0.59 kg/m2; 95% CI = -1.14, -0.04). CONCLUSIONS: In secondary analyses, NET-Works significantly reduced BMI over 3 years among Hispanic children and children with baseline overweight or obesity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01606891.

Effect of a Behavioral Intervention for Underserved Preschool-Age Children on Change in Body Mass Index: A Randomized Clinical Trial.

Importance: Prevention of obesity during childhood is critical for children in underserved populations, for whom obesity prevalence and risk of chronic disease are highest. Objective: To test the effect of a multicomponent behavioral intervention on child body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) growth trajectories over 36 months among preschool-age children at risk for obesity. Design, Setting, and Participants: A randomized clinical trial assigned 610 parent-child pairs from underserved communities in Nashville, Tennessee, to a 36-month intervention targeting health behaviors or a school-readiness control. Eligible children were between ages 3 and 5 years and at risk for obesity but not yet obese. Enrollment occurred from August 2012 to May 2014; 36-month follow-up occurred from October 2015 to June 2017. Interventions: The intervention (n = 304 pairs) was a 36-month family-based, community-centered program, consisting of 12 weekly skills-building sessions, followed by monthly coaching telephone calls for 9 months, and a 24-month sustainability phase providing cues to action. The control (n = 306 pairs) consisted of 6 school-readiness sessions delivered over the 36-month study, conducted by the Nashville Public Library. Main Outcomes and Measures: The primary outcome was child BMI trajectory over 36 months. Seven prespecified secondary outcomes included parent-reported child dietary intake and community center use. The Benjamini-Hochberg procedure corrected for multiple comparisons. Results: Participants were predominantly Latino (91.4%). At baseline, the mean (SD) child age was 4.3 (0.9) years; 51.9% were female. Household income was below $25 000 for 56.7% of families. Retention was 90.2%. At 36 months, the mean (SD) child BMI was 17.8 (2.2) in the intervention group and 17.8 (2.1) in the control group. No significant difference existed in the primary outcome of BMI trajectory over 36 months (P = .39). The intervention group children had a lower mean caloric intake (1227 kcal/d) compared with control group children (1323 kcal/d) (adjusted difference, -99.4 kcal [95% CI, -160.7 to -38.0]; corrected P = .003). Intervention group parents used community centers with their children more than control group parents (56.8% in intervention; 44.4% in control) (risk ratio, 1.29 [95% CI, 1.08 to 1.53]; corrected P = .006). Conclusions and Relevance: A 36-month multicomponent behavioral intervention did not change BMI trajectory among underserved preschool-age children in Nashville, Tennessee, compared with a control program. Whether there would be effectiveness for other types of behavioral interventions or implementation in other cities would require further research. Trial Registration: ClinicalTrials.gov Identifier: NCT01316653.

Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents.

BACKGROUND: Overweight and obesity are increasing worldwide. To help assess their relevance to mortality in different populations we conducted individual-participant data meta-analyses of prospective studies of body-mass index (BMI), limiting confounding and reverse causality by restricting analyses to never-smokers and excluding pre-existing disease and the first 5 years of follow-up. METHODS: Of 10 625 411 participants in Asia, Australia and New Zealand, Europe, and North America from 239 prospective studies (median follow-up 13·7 years, IQR 11·4-14·7), 3 951 455 people in 189 studies were never-smokers without chronic diseases at recruitment who survived 5 years, of whom 385 879 died. The primary analyses are of these deaths, and study, age, and sex adjusted hazard ratios (HRs), relative to BMI 22·5-<25·0 kg/m(2). FINDINGS: All-cause mortality was minimal at 20·0-25·0 kg/m(2) (HR 1·00, 95% CI 0·98-1·02 for BMI 20·0-<22·5 kg/m(2); 1·00, 0·99-1·01 for BMI 22·5-<25·0 kg/m(2)), and increased significantly both just below this range (1·13, 1·09-1·17 for BMI 18·5-<20·0 kg/m(2); 1·51, 1·43-1·59 for BMI 15·0-<18·5) and throughout the overweight range (1·07, 1·07-1·08 for BMI 25·0-<27·5 kg/m(2); 1·20, 1·18-1·22 for BMI 27·5-<30·0 kg/m(2)). The HR for obesity grade 1 (BMI 30·0-<35·0 kg/m(2)) was 1·45, 95% CI 1·41-1·48; the HR for obesity grade 2 (35·0-<40·0 kg/m(2)) was 1·94, 1·87-2·01; and the HR for obesity grade 3 (40·0-<60·0 kg/m(2)) was 2·76, 2·60-2·92. For BMI over 25·0 kg/m(2), mortality increased approximately log-linearly with BMI; the HR per 5 kg/m(2) units higher BMI was 1·39 (1·34-1·43) in Europe, 1·29 (1·26-1·32) in North America, 1·39 (1·34-1·44) in east Asia, and 1·31 (1·27-1·35) in Australia and New Zealand. This HR per 5 kg/m(2) units higher BMI (for BMI over 25 kg/m(2)) was greater in younger than older people (1·52, 95% CI 1·47-1·56, for BMI measured at 35-49 years vs 1·21, 1·17-1·25, for BMI measured at 70-89 years; pheterogeneity<0·0001), greater in men than women (1·51, 1·46-1·56, vs 1·30, 1·26-1·33; pheterogeneity<0·0001), but similar in studies with self-reported and measured BMI. INTERPRETATION: The associations of both overweight and obesity with higher all-cause mortality were broadly consistent in four continents. This finding supports strategies to combat the entire spectrum of excess adiposity in many populations. FUNDING: UK Medical Research Council, British Heart Foundation, National Institute for Health Research, US National Institutes of Health.

Cardiovascular Disease Mortality Among Breast Cancer Survivors.

BACKGROUND: Cardiovascular disease (CVD) is of increasing concern among breast cancer survivors. However, the burden of this comorbidity in this group relative to the general population, and its temporal pattern, remains unknown. METHODS: We compared deaths due to CVD in a population-based sample of 1,413 women with incident breast cancer diagnosed in 1996-1997, and 1,411 age-matched women without breast cancer. Date and cause of death through December 31, 2009 were assessed through the national death index and covariate data was gathered through structured interviews and medical record abstraction. Hazard ratios (HR) and 95% confidence intervals were calculated using Cox regression for overall mortality (HR) and CVD-specific death (cause-specific HR). Subdistribution HRs for CVD death were estimated from the Fine-Gray model. RESULTS: Risk of death was greater among breast cancer survivors compared with women without breast cancer (HR: 1.8 [1.5, 2.1]). An increase in CVD-related death among breast cancer survivors was evident only 7 years after diagnosis (years 0-7, cause-specific HR: 0.80 [0.53, 1.2], subdistribution HR: 0.59 [0.40, 0.87]); years 7+, cause-specific HR: 1.8 [1.3, 2.5], subdistribution HR: 1.9 [1.4, 2.7]; P interaction: 0.001). An increase in CVD-related mortality was observed among breast cancer survivors receiving chemotherapy. CONCLUSIONS: Breast cancer survivors are at greater risk for CVD-related mortality compared with women without breast cancer and this increase in risk is manifested approximately 7 years after diagnosis. Efforts should be made to identify risk factors and interventions that can be employed during this brief window to reduce the excess burden of CVD in this vulnerable population.

Validity and reliability of the semi-quantitative self-report Home Food Availability Inventory Checklist (HFAI-C) in White and South Asian populations.

BACKGROUND: Despite interest in the importance of the home food environment and its potential influence on children's diets and social norms, there remain few self-report checklist methods that have been validated against the gold standard of researcher-conducted inventories. This study aimed to assess the criterion validity and reliability of the 'Home Food Availability Inventory Checklist' (HFAI-C), a 39-item checklist including categories of fruit, vegetables, snacks and drinks. METHODS: The HFAI-C was completed by 97 participants of White and Pakistani origin in the UK. Validity was determined by comparing participant-reported HFAI-C responses to data from researcher observations of home food availability using PABAK and weighted kappa statistics. The validity of measuring the amount of items (in addition to presence/absence) available was also determined. Test-retest reliability compared repeated administrations of the HFAI-C using intra-class correlation coefficients. RESULTS: Validity and reliability was fair to moderate overall. For validity, the average category-level PABAK ranged from 0.31 (95% CI: 0.25, 0.37) for vegetables to 0.44 (95% CI: 0.40, 0.49) for fruits. Assessment of the presence/absence of items demonstrated higher validity compared to quantity measurements. Reliability was increased when the HFAI-C was repeated close to the time of the first administration. For example, ICCs for reliability of the measurement of fruits were 0.52 (95%CI: 0.47, 0.56) if re-administered within 5 months, 0.58 (95% CI: 0.51, 0.64) within 30 days and 0.97 (95%CI: 0.94, 1.00) if re-administered on the same day. CONCLUSIONS: Overall, the HFAI-C demonstrated fair to moderate validity and reliability in a population of White and South Asian participants. This evaluation is consistent with previous work on other checklists in less diverse, more affluent populations. Our research supports the use of the HFAI-C as a useful, albeit imperfect, representation of researcher-conducted inventories. The feasibility of collecting information using the HFAI-C in large, multi-ethnic samples can facilitate examination of home food availability in relation to exposures such as ethnicity and outcomes including behavioural, social and health outcomes. Future work using the HFAI-C could provide important insights into a modifiable influence with potential to impact health.

Invited commentary: limitations and usefulness of the metabolically healthy obesity phenotype.

The fraction of the obese population who appear to be free of the metabolic abnormalities that usually accompany excess adiposity has garnered a great deal of attention recently. The so-called "metabolically healthy obesity" concept is thought to offer a refinement of the traditional obesity definitions that are based solely on anthropometry. The commentary by Rey-López et al. (Am J Epidemiol. 2015;182(9):737-741) in this issue of the Journal highlights several limitations of the "metabolically healthy obesity" concept and calls into question its usefulness as a public health metric. We discuss several of the issues raised by these authors and offer some perspective on why the utility of this concept remains unresolved.

Longitudinal study of acculturation and BMI change among Asian American men.

BACKGROUND: Cross-sectional studies examining the association between Western acculturation and BMI in Asians have been inconsistent, and studies on BMI change are lacking. OBJECTIVE: This study examined the associations between indicators of acculturation (generational status, length of US residence, and age at immigration) and overweight (BMI ≥25kg/m(2)) as well as 5-year BMI changes in 7,073 Chinese, Japanese, Korean, Filipino, and Vietnamese men who lived in the US and were 44-71years old at baseline of the California Men's Health Study (2002-2003). METHODS: Indicators of acculturation were reported at baseline. Repeated clinical measures of BMI were extracted from electronic health records (2005-2012). RESULTS: Using generalized estimating equations we found that lower generational status, shorter duration of US residence and older age at immigration were inversely associated with being overweight. However, analysis of BMI curves using linear mixed models showed that shorter length of US residence and older age at immigration were associated with larger 5-year increases in BMI. CONCLUSIONS: Asian immigrants who were less acculturated had larger BMI increases as they became more acculturated but had not achieved overweight status. Healthy weight interventions among Asians immigrants may be most effective when targeting weight maintenance early in the process of acculturation.

Body mass index at early adulthood, subsequent weight change and cancer incidence and mortality.

Obesity later in adulthood is associated with increased risks of many cancers. However, the effect of body fatness in early adulthood, and change in weight from early to later adulthood on cancer risk later in life is less clear. We used data from 13,901 people aged 45-64 in the Atherosclerosis Risk in Communities cohort who at baseline (1987-1989) self-reported their weight at the age of 25 and had weight and height measured. Incident cancers were identified through 2006 and cancer deaths were ascertained through 2009. Multivariable Cox proportional hazard models were used to relate body mass index (BMI) at age 25 and percent weight change from age 25 to baseline to cancer incidence and mortality. After adjusting for weight change from age 25 until baseline, a 5 kg/m(2) increment in BMI at age 25 was associated with a greater risk of incidence of all cancers in women [hazard ratio (95% confidence interval): 1.10 (1.02-1.20)], but not in men. Associations with incident endometrial cancer were strong [1.83 (1.47-2.26)]. After adjusting for BMI at age 25, a 5% increment in weight from age 25 to baseline was associated with a greater risk of incident postmenopausal breast cancer [1.05 (1.02-1.07)] and endometrial cancer [1.09 (1.04-1.14)] in women and incident colorectal cancer [1.05 (1.00-1.10)] in men. Excess weight during young adulthood and weight gain from young to older adulthood may be independently associated with subsequent cancer risk. Excess weight and weight gain in early adulthood should be avoided.

Post-diagnosis physical activity and survival after breast cancer diagnosis: the Long Island Breast Cancer Study.

Physical activity (PA) is associated with physiological responses thought to beneficially affect survival after breast cancer diagnosis, yet few studies have considered the entire survivorship experience. Effects of post-diagnosis activity on survival were examined in a cohort of 1,423 women diagnosed with in situ or invasive breast cancer in 1996-1997. Subjects were interviewed soon after diagnosis and again after approximately 5 years to assess breast cancer-related factors, including recreational PA before and after diagnosis. Date and cause of death through 2009 were determined from the National Death Index. Adjusted estimates were obtained using proportional hazards regression and a selection model to account for missing data. Survival was improved among women who were highly active after diagnosis (>9.0 MET h/week) compared to inactive women (0 MET h/week) for all-cause [hazard ratio (HR) (95 % credible interval): 0.33 (0.22, 0.48)] and breast cancer-specific mortality [HR: 0.27 (0.15, 0.46)]. The association of PA with overall mortality appeared stronger in the first 2 years after diagnosis [HR: 0.14 (0.03, 0.44)] compared to 2+ years since diagnosis [HR: 0.37 (0.25, 0.55)]. These findings show that post-diagnosis PA is associated with improved survival among women with breast cancer.

Smoking and risk of coronary heart disease in younger, middle-aged, and older adults.

OBJECTIVES: We investigated associations of smoking and coronary heart disease (CHD) by age. METHODS: Data came from the Pooling Project on Diet and Coronary Heart Disease (8 prospective studies, 1974-1996; n = 192,067 women and 74,720 men, aged 40-89 years). RESULTS: During follow-up, 4326 cases of CHD were reported. Relative to never smokers, CHD risk among current smokers was highest in the youngest and lowest in the oldest participants. For example, among women aged 40 to 49 years the hazard ratio was 8.5 (95% confidence interval [CI] = 5.0, 14) and 3.1 (95% CI = 2.0, 4.9) among those aged 70 years or older. The largest absolute risk differences between current smokers and never smokers were observed among the oldest participants. Finally, the majority of CHD cases among smokers were attributable to smoking. For example, attributable proportions of CHD by age group were 88% (40-49 years), 81% (50-59 years), 71% for (60-69 years), and 68% (≥ 70 years) among women who smoked. CONCLUSIONS: Among smokers, the majority of CHD cases are attributable to smoking in all age groups. Smoking prevention is important, irrespective of age.

Childhood obesity prevention trials: A systematic review and meta-analysis on trial design and the impact of type 1 error.

Effect sizes from previously reported trials are often used to determine the meaningful change in weight in childhood obesity prevention interventions because information on clinically meaningful differences is lacking. Estimates from previous trials may be influenced by statistical significance; therefore, it is important that they have a low risk of type 1 error. A systematic review and meta-analysis were conducted to report on the design of child obesity prevention randomized controlled trials and effectiveness according to risk of type 1 error. Eighty-four randomized controlled trials were identified. A large range of assumptions were applied in the sample size calculations. The most common primary outcome was BMI, with detectable effect size differences used in sample size calculations ranging from 0.25 kg/m2 (followed up at 2 years) to 1.1 kg/m2 (at 9 months) and BMI z-score ranging from 0.1 (at 4 years) to 0.67 (at 3 years). There was no consistent relationship between low risk of type 1 error and reports of higher or lower effectiveness. Further clarity of the size of a meaningful difference in weight in childhood obesity prevention trials is required to support evaluation design and decision-making for intervention and policy. Type 1 error risk does not appear to impact effect sizes in a consistent direction.

Long- and short-term weight change and incident coronary heart disease and ischemic stroke: the Atherosclerosis Risk in Communities Study.

Weight gain increases the prevalence of obesity, a risk factor for cardiovascular disease. Nevertheless, unintentional weight loss can be a harbinger of health problems. The Atherosclerosis Risk in Communities Study (1987-2009) included 15,792 US adults aged 45-64 years at baseline and was used to compare associations of long-term (30 years) and short-term (3 years) weight change with the risks of coronary heart disease (CHD) and ischemic stroke. Age-, gender-, and race-standardized incidence rates were 4.9 (95% confidence interval (CI): 4.6, 5.2) per 1,000 person-years for CHD and 2.5 (95% CI: 2.3, 2.8) per 1,000 person-years for stroke. After controlling for baseline body mass index and other covariates, long-term weight gain (since age 25 years) of more than 2.7% was associated with elevated CHD risk, and any long-term weight gain was associated with increased stroke risk. Among middle-aged adults, short-term (3-year) weight loss of more than 3% was associated with elevated immediate CHD risk (hazard ratio = 1.46, 95% CI: 1.18, 1.81) and stroke risk (hazard ratio = 1.45, 95% CI: 1.10, 1.92). Risk tended to be larger in adults whose weight loss did not occur through dieting. Avoidance of weight gain between early and middle adulthood can reduce risks of CHD and stroke, but short-term, unintentional weight loss in middle adulthood may be an indicator of immediate elevated risk that has not previously been well recognized.