Birth weight, components of height and coronary heart disease: evidence from the Whitehall II study

The Association between Birthweight and Use of Cardiovascular Medications: The Role of Health Behaviors

BACKGROUND

There is limited evidence on the effect of low birthweight on the use of cardiovascular medications and the role of health behaviors. This study aims to determine the independent effect of low birthweight and its combination with adult health behaviors on the number of dispensed cardiovascular medications.

METHODS

We included 15618 participants with information on birthweight and self-reported health behaviors. Dispensed cardiovascular medications were identified from the Prescribed Drug Register based on a three-digit level Anatomical Therapeutic Chemical classification code (C01 to C10 and B01) and categorized into 0, 1, and ≥2 different types of medications. We applied multinomial logistic regression models estimating odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Participants with low birthweight had a higher estimated OR of using ≥2 types of cardiovascular medications (OR = 1.46, 95% CI = 1.06, 2.01). Further, an increased risk for using ≥2 types of cardiovascular medications was found in participants with poor health behaviors for normal (OR = 2.17, 95% CI = 1.80, 2.62) and high (OR = 1.84, 95% CI = 1.29, 2.62) birthweight. The strongest effect on using ≥2 types of cardiovascular medications was found for low birthweight and poor health behaviors (OR = 3.14, 95% CI = 1.80, 5.50).

CONCLUSION

This cohort study provides evidence that low birthweight increases the risk of using more types of cardiovascular medications in adulthood. This study also suggests that ideal health behaviors reduce this risk.

Preferential deposition of dairy derived fatty acids in muscle tissue is partially due to the upregulation of CD36 in a low-birth-weight swine model

Metabolic syndrome is a worldwide health issue. Previous research has revealed that low-birth weight (LBW) swine fed a high-fat (HF) diet were susceptible to insulin resistance (IR) and developed a preferential intestinal lipid absorption, hypertriglyceridemia, and muscle steatosis. We hypothesized that fatty acid transporters such as CD36, FATP4, and FABP2 could potentially explain the development of these conditions. In addition, dairy-derived fatty acids have been shown to be valid biomarkers to assess dairy intake, which can be utilized to investigate muscle lipid deposition in LBW swine. The overall aim of this study was to delineate molecular transport candidates responsible for intestinal lipid absorption and muscle lipid deposition in LBW swine; and secondly to determine what dietary fatty acids might accumulate preferentially in pork muscle when consuming dairy products. At 5 weeks of age, normal birth weight (NBW) and LBW piglets were randomly assigned to three experimental diets: 1-chow diet, 2-HF diet, or 3-isocaloric HF diet supplemented with full fat dairy products. At 12 weeks of age, piglets were euthanized, and carcass, fasting plasma, biceps femoris and jejunum mucosal scrapings were collected. Results showed that HF-fed LBW swine exhibited early signs of IR (fasting glucose, P < 0.05; fasting insulin, P = 0.091; HOMA-IR, P = 0.086) compared with NBW-Chow, which were attenuated with increased dairy intake. Muscle samples from HF-fed LBW swine contained significantly more triglyceride compared to Chow-fed NBW swine (P < 0.05). Increased dairy intake significantly increased myristic acid (C14:0) and DPA (C22:5n3) relative to HF feeding alone (P < 0.05). All HF-fed LBW swine (regardless of dairy intake) exhibited an upregulation of CD36 expression (but not FABP2) compared with NBW littermates in both the small intestine and muscle (P < 0.05). Interestingly, increased dairy intake significantly increased the Canadian Lean Yield percentage in LBW swine fed an HF diet (P < 0.05). Findings from this study provide evidence on the mechanistic pathway of intestinal and muscle lipid metabolism in an innovative LBW swine model. We have also revealed that increasing dairy intake can enhance the incorporation of dietary long-chain polyunsaturated fatty acids into pork, as well as increasing the predicted lean yield of the carcass.

Associations of birth weight and later life lifestyle factors with risk of cardiovascular disease in the USA: A prospective cohort study

BACKGROUND

Low birth weight has been associated with a greater risk of cardiovascular disease (CVD). However, the interaction between low birth weight and adult lifestyle factors on the risk of CVD remains unclear.

METHODS

We included 20,169 men from the Health Professionals Follow-up Study (HPFS, 1986-2016), 52,380 women from the Nurses' Health Study (NHS, 1980-2018), and 85,350 women from the Nurses' Health Study II (NHS II, 1991-2017) in the USA who reported birth weight and updated data on adult body weight, smoking status, physical activity, and diet every 2-4 years. Incident cases of CVD, defined as a combined endpoint of fatal and nonfatal coronary heart disease (CHD) and stroke, were self-reported and confirmed by physicians through reviewing medical records.

FINDINGS

During 4,370,051 person-years of follow-up, 16,244 incident CVD cases were documented, including 12,126 CHD and 4118 stroke cases. Cox proportional hazards regression models revealed an increased risk of CHD during adulthood across categories of decreasing birth weight in all cohorts (all P for linear trend <0.001). Additionally, we found an additive interaction between decreasing birth weight and unhealthy lifestyles on the risk of CHD among women, with a pooled relative excess risk due to interaction of 0.06 (95% CI: 0.04-0.08). The attributable proportions of the joint effect were 23.0% (95% CI: 11.0-36.0%) for decreasing birth weight alone, 67.0% (95% CI: 58.0-75.0%) for unhealthy lifestyle alone, and 11.0% (95% CI: 5.0-17.0%) for their additive interaction. Lower birth weight was associated with a greater stroke risk only among women, which was independent of later-life lifestyle factors.

INTERPRETATION

Lower birth weight may interact synergistically with unhealthy lifestyle factors in adulthood to further increase the risk of CHD among women.

FUNDING

The National Institutes of Health grants.

The Causal Evidence of Birth Weight and Female-Related Traits and Diseases: A Two-Sample Mendelian Randomization Analysis

Objectives: A large meta-analysis indicated a more pronounced association between lower birth weight (BW) and diseases in women but less concern about the causality between BW and female-related phenotypes and diseases.

Methods: Mendelian randomization (MR) analysis was used to estimate the causal relationship between two traits or diseases using summary datasets from genome-wide association studies. Exposure instrumental variables are variants that are strongly associated with traits and are tested using four different statistical methods, including the inverse variance weighting, MR-Egger, weighted median, and weighted mode in MR analysis. Next, sensitivity analysis and horizontal pleiotropy were assessed using leave-one-out and MR-PRESSO packages.

Results: The body mass index (BMI) in adulthood was determined by BW (corrected β = 0.071, p = 3.19E-03). Lower BW could decrease the adult sex hormone-binding globulin (SHBG) level (β = −0.081, p = 2.08E-06), but it resulted in increased levels of bioavailable testosterone (bio-T) (β = 0.105, p = 1.25E-05). A potential inverse effect was observed between BW and menarche (corrected β = −0.048, p = 4.75E-03), and no causal association was confirmed between BW and the risk of endometriosis, leiomyoma, and polycystic ovary syndrome.

Conclusion: Our results suggest that BW may play an important role and demonstrates a significant direct influence on female BMI, SHBG and bio-T levels, and menarche.

Body height determines carotid stiffness following resistance exercise in young Japanese men

Height is inversely associated with an increase in arterial stiffness after habitual resistance exercise (RE). Considering that RE is performed during exercise prescriptions, the association between height and the acute effects of RE on arterial stiffness should be clarified. We investigated the effects of height on arterial stiffness following transient RE. Thirty-nine young Japanese men were studied under parallel experimental conditions (sham control [seated rest] and RE [5 sets of 10 repetitions at 75% of one-repetition maximum]), which were randomly ordered on two separate days. The subjects were divided into tertiles of height (each group, n = 13). The β-stiffness index (index of arterial stiffness), assessed by carotid pulse pressure and distension, was measured in all subjects. A significant interaction between time, height, and RE was found for the β-stiffness index (P = 0.01). RE significantly increased the β-stiffness index in the lower height group (P < 0.001), but not in the middle and higher height groups. Height was negatively associated with an increase in β-stiffness index following RE, even after controlling the confounders, including exercise volume and changes in heart rate and carotid pulse pressure (P = 0.003). The mediation analysis demonstrated a mediating effect of carotid distension on the relationship between height and changes in the β-stiffness index. These results suggest that short height individuals have increased arterial stiffness following RE due to decreased mechanical distension, rather than through the widening of pulsatile pressure.

The Relationship between Adult Height and Blood Pressure

BACKGROUND

Identification and modification of cardiovascular risk factors is paramount to reducing cardiovascular disease morbidity and mortality. Hypertension is a major risk factor for cardiovascular disease, but its association with height remains largely underrecognized.

OBJECTIVES

The objective of this manuscript is to review the evidence examining the association between blood pressure and human stature and to summarize the plausible pathophysiological mechanisms behind such an association.

METHODS

A systematic review of adult human height and its association with hypertension and coronary artery disease was undertaken. The literature evidence is summarized and tabulated, and an overview of the pathophysiological basis for this association is presented.

RESULTS

Shorter arterial lengths found in shorter individuals may predispose to hypertension in a complex hemodynamic interplay, which is explained predominantly by summated arterial wave reflections and an elevated augmentation index. Our systemic review suggests that an inverse relationship between adult height and blood pressure exists. However, differences in the studied populations and heterogeneity in the methods applied across the various studies limit the generalizability of these findings and their clinical application.

CONCLUSION

Physiological studies and epidemiological data suggest a potential inverse association between adult height and blood pressure. Further research is required to define the relationship more clearly between adult height and blood pressure and to assess whether antihypertensive therapeutic approaches and goals should be modified according to patients' heights.

Association between serum uric acid and triglycerides in Chinese children and adolescents with short stature

Background

Elevated triglyceride (TG) levels are a biomarker for cardiovascular disease (CVD) risk. The correlation between serum uric acid (SUA) and TG concentrations in adults or obese children is well established. However, studies on SUA and TG in children with short stature are limited.

Aim

To determine the relationship between SUA and TG levels in short children and adolescents.

Method

This was a cross-sectional evaluation of a cohort of 1095 patients with short stature (720 males and 375 females). The related clinical characteristics, including anthropometric and biochemical parameters, were determined.

Results

Smooth curve fitting, adjusted for potential confounders was performed, which indicated the existence of a non-linear relationship between these measures. Piecewise multivariate linear analysis revealed a significant positive relationship between SUA and TG at SUA concentrations over 7 mg/dL (β = 0.13, 95% CI: 0.05–0.22, P = 0.002) but no significant correlation at lower SUA levels (β = 0.01, 95% CI: 0.01–0.04, P = 0.799). Furthermore, a stratified analysis was performed to appraise changes in this relationship for different sexes and standard deviation levels of body mass index (BMI). The non-linear relationship remained consistent in males and females with BMI standard deviation scores (BMI SDS) ≥ 0, with inflection points of 6.71 mg/dL and 3.93 mg/dL, respectively. Within these two groups, SUA and TG levels showed a positive association when SUA levels were higher than the inflection point (β = 0.21, 95% CI: 0.11–0.31, P < 0.001 for males and β = 0.1, 95% CI: 0.03–0.17, P = 0.005 for females). However, a specific relationship was not observed at lower SUA levels. No significant relationships were found between SUA and TG levels in males and females with BMI SDS < 0.

Conclusion

The present study identified the non-linear association of SUA and TG levels with short children and adolescents. This relationship was based on BMI status. This finding suggests that health status should be considered for short stature children with high SUA levels, especially in children with a high BMI standard deviation score.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-020-01429-x.

Developmental and Early Life Origins of Cardiometabolic Risk Factors: Novel Findings and Implications

The intent of this review is to critically consider the data that support the concept of programming and its implications. Birth weight and growth trajectories during childhood are associated with cardiometabolic disease in adult life. Both extremes, low and high birth weight coupled with postnatal growth increase the early presence of cardiometabolic risk factors and vascular imprinting, crucial elements of this framework. Data coming from epigenetics, proteomics, metabolomics, and microbiota added relevant information and contribute to better understanding of mechanisms as well as development of biomarkers helping to move forward to take actions. Research has reached a stage in which sufficiently robust data calls for new initiatives focused on early life. Prevention starting early in life is likely to have a very large impact on reducing disease incidence and its associated effects at the personal, economic, and social levels.

Disproportion and dysmorphism in an adult Belgian population with Turner syndrome: risk factors for chronic diseases?

BACKGROUND

Turner syndrome (TS) is characterized by dysmorphism and body disproportion. TS women are also susceptible to a range of chronic disorders including arterial hypertension (AHT), osteoporosis, sensorineural hearing loss (SNHL), type 2 diabetes mellitus (DM2) and thyroid disease. The association between dysmorphism/body disproportion and chronic disease has never been studied in TS women. The effect of growth hormone treatment on body disproportion is also unclear. Objectives: to analyze dysmorphic features and body disproportion in TS women in relation to the presence of chronic disease and to document the effect of growth hormone therapy on body disproportion.

METHOD

76 adult TS women with a regular follow up at the TS clinic UZ Ghent were invited to participate. Detailed body measurements were performed in 44 volunteering TS women. Scoring systems for overall dysmorphism, craniofacial dysmorphism, thoracic and limb abnormalities and skeletal disproportion were developed.

RESULTS

TS women with a higher dysmorphism score were more at risk for AHT (p = 0.04) as well as those with a higher sitting height/standing height ratio (p < 0.05). Prevalence of AHT, osteoporosis and DM 2 was lower in TS women treated with GH during childhood (p < 0.05).

CONCLUSIONS

Adult TS women with relatively short legs or with more physical dysmorphic stigmata were more at risk for AHT. GH therapy does not seem to increase the risk of chronic disease on the long term.

Birth Weight and Risk of Type 2 Diabetes Mellitus, Cardiovascular Disease, and Hypertension in Adults: A Meta-Analysis of 7 646 267 Participants From 135 Studies

Background Low birth weight has been associated with increased risk of type 2 diabetes mellitus, cardiovascular disease, and hypertension, but the risk at high birth weight levels remains uncertain. This systematic review and meta-analysis aimed to clarify the shape of associations between birth weight and aforementioned diseases in adults and assessed sex-specific risks. Methods and Results We systematically searched PubMed, EMBASE , and Web of Science for studies published between 1980 and October 2016. Studies of birth weight and type 2 diabetes mellitus (T2 DM ), cardiovascular disease ( CVD ), and hypertension were included. Random-effects models were used to derive the summary relative risks and corresponding 95% confidence intervals.We identified 49 studies with 4 053 367 participants assessing the association between birth weight and T2 DM , 33 studies with 5 949 477 participants for CVD , and 53 studies with 4 335 149 participants for hypertension and high blood pressure. Sex-specific binary analyses showed that only females had an increased risk of T2 DM and CVD at the upper tail of the birth weight distribution. While categorical analyses of 6 birth weight groups and dose-response analyses showed J-shaped associations of birth weight with T2 DM and CVD , the association was inverse with hypertension. The lowest risks for T2 DM , CVD , and hypertension were observed at 3.5 to 4.0, 4.0 to 4.5, and 4.0 to 4.5 kg, respectively. Conclusions These findings indicate that birth weight is associated with risk of T2 DM and CVD in a J-shaped manner and that this is more pronounced among females.

Low-density lipoprotein cholesterol levels are associated with insulin-like growth factor-1 in short-stature children and adolescents: a cross-sectional study

BACKGROUND

Elevated low-density lipoprotein cholesterol (LDL-C) levels in childhood have recently been found to be the strongest predictive risk factor for coronary artery disease in adulthood. There is an increased level of LDL-C in children and adolescents with short stature. However, the underlying factors associated with increased LDL-C levels in children and adolescents with short stature are unknown. In addition, the insulin-like growth factor 1 (IGF-1) level in the short-stature population is usually below the normal reference range. The aim of this study was to investigate the relationship between IGF-1 standard deviation score (IGF-1 SDS) and LDL-C level in children and adolescents with short stature.

METHODS

A cross-sectional study was conducted in a single centre of China, 557 short-stature children and adolescents whose height SDS was lower than - 2 SD after adjustment for age and gender were included. The related clinical and laboratory examinations, including anthropometric parameters, lipid profiles, IGF-1 levels and the levels of other cofactors, were assessed in all participants.

RESULTS

The univariate analysis results showed a significant negative correlation between IGF-1 SDS and LDL-C levels (P = 0.006). Furthermore, a nonlinear relationship was observed between IGF-1 SDS and LDL-C by smooth curve fitting after adjusting for possible confounders. A multivariate piecewise linear regression model revealed a significant negative correlation between IGF-1 SDS and LDL-C when the IGF-1 level was greater than - 2 SDS (β - 0.07, 95% CI -0.12, - 0.02; P = 0.006). However, we did not observe a significant relationship between IGF-1 SDS and LDL-C when the IGF-1 level was lower than - 2 SDS (β 0.08, 95% CI -0.02, 0.17; P = 0.119).

CONCLUSION

This study demonstrated a nonlinear relationship between IGF-1 and LDL-C independent of other potential confounding factors, suggesting that circulating IGF-1 may contribute to the regulation of LDL-C levels, thus meriting further investigation.

Distinctive lung function trajectories from age 10 to 26 years in men and women and associated early life risk factors - a birth cohort study

Pre-bronchodilator lung function including forced vital capacity (FVC), forced expiratory flow in 1 second (FEV1), their ratio (FEV1/FVC), and forced expiratory flow 25-75% (FEF25-75) measured at age 10, 18, and 26 years in the Isle of Wight birth cohort was analyzed for developmental patterns (trajectories). Early life risk factors before the age of 10 years were assessed for the trajectories.

METHOD

Members of the birth cohort (1989/90) were followed at age 1, 2, 4, 10, 18, and 26 years. Allergic sensitization and questionnaire data were collected. Spirometry tests were performed and evaluated according to the American Thoracic Society (ATS) criteria at 10, 18, and 26 years. To identify developmental trajectories for FVC, FEV1, FEV1/FVC, and FEF25-75 from 10 to 26 years, a finite mixture model was applied to the longitudinal lung function data, separately for males and females. Associations of early life factors with the respective lung function trajectories were assessed using log-linear and logistic regression analyses.

RESULTS

Both high and low lung function trajectories were observed in men and women. FVC continued to grow beyond 18 years in men and women, whereas FEV1 peaked at age 18 years in female trajectories and in one male trajectory. For the FEV1/FVC ratios and FEF25-75 most trajectories appeared highest at age 18 and declined thereafter. However, the low FEV1/FVC trajectory in both sexes showed an early decline at 10 years. Lower birth weight was linked with lower lung function trajectories in males and females. Eczema in the first year of life was a risk factor for later lung function deficits in females, whereas the occurrence of asthma at 4 years of age was a risk factor for later lung function deficits in males. A positive skin prick test at age four was a risk for the low FEV1 trajectory in females and for the low FEV1/FVC trajectory in males.

CONCLUSION

Men and women showed distinctive lung function trajectories and associated risk factors. Lower lung function trajectories can be explained by not achieving maximally attainable function at age 18 years and by a function decline from 18 to 26 years.

Maternal undernutrition during early pregnancy inhibits postnatal growth of the tibia in the female offspring of rats by alteration of chondrogenesis

Epidemiological research has suggested that birth weights are correlated with adult leg lengths. However, the relationship between prenatal undernutrition (UN) and postnatal leg growth remains controversial. We investigated the effects of UN during early pregnancy on postnatal hindlimb growth and determined whether early embryonic malnutrition affects the functions of postnatal chondrocytes in rats. Undernourished Wistar dams were fed 40% of the daily intake of rats in the control groups from gestational days 5.5-11.5, and femurs, tibias, and trunks or spinal columns were morphologically measured at birth and at 16 weeks of age in control and undernourished offspring of both sexes. We evaluated cell proliferation and differentiation of cultured chondrocytes derived from neonatal tibias of female offspring and determined chondrocyte-related gene expression levels in neonatal epiphysis and embryonic limb buds. Tibial lengths of undernourished female, but not male, offspring were longer at birth and shorter at 16 weeks of age (p < .05) compared with those of control rats. In chondrocyte culture studies, stimulating effects of IGF-1 on cell proliferation (p < .01) were significantly decreased and levels of type II collagen were lower in female undernourished offspring (p < .05). These phenomena were accompanied by decreased expression levels of Col2a1 and Igf1r and increased expression levels of Fgfr3 (p < .05), which might be attributable to the decreased expression of specificity protein 1 (p < .05), a key transactivator of Col2a1 and Igf1r. In conclusion, UN stress during early pregnancy reduces postnatal tibial growth in female offspring by altering the function of chondrocytes, likely reflecting altered expression of gene transactivators.

Early-life nutritional status and metabolic syndrome: gender-specific associations from a cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

OBJECTIVE

In the present study we investigated gender-specific associations of low birth weight (LBW) and shorter relative leg length with metabolic syndrome (MetS) after adjusting for sociodemographic characteristics and health-related behaviours. We also investigated whether these associations are independent of age at menarche and BMI at 20 years old.

DESIGN

Cross-sectional analysis.

SUBJECTS

Baseline data from 12 602 participants (35-74 years) of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), 2008-2010.

SETTING

MetS was defined according to the revised National Cholesterol Education Program Adult Treatment Panel III guidelines. LBW (<2·5 kg) and age- and sex-standardized relative leg length (high, medium and low) were the explanatory variables studied. The strength of the associations between the explanatory variables and MetS was estimated by Poisson regression with robust variance.

RESULTS

MetS prevalence was 34·2 %; it was more prevalent in men (36·8 %) than in women (32·2 %). In multivariate analysis, LBW was associated (prevalence ratio; 95 % CI) with MetS only in women (1·28; 1·24, 1·45). Shorter leg length was associated with MetS in both men (1·21; 1·09, 1·35 and 1·46; 1·29, 1·65 for low and medium lengths, respectively) and women (1·12; 1·00, 1·25 and 1·40; 1·22, 1·59 for low and medium lengths, respectively). Additional adjustments for age at menarche and BMI at 20 years old did not change the associations.

CONCLUSIONS

Poor nutritional status as estimated by LBW and lower leg length in childhood was associated with a higher prevalence of MetS, although LBW was a significant factor only among women.

Explaining ethnic disparities in lung function among young adults: A pilot investigation

Background

Ethnic disparities in lung function have been linked mainly to anthropometric factors but have not been fully explained. We conducted a cross-sectional pilot study to investigate how best to study ethnic differences in lung function in young adults and evaluate whether these could be explained by birth weight and socio-economic factors.

Methods

We recruited 112 university students of White and South Asian British ethnicity, measured post-bronchodilator lung function, obtained information on respiratory symptoms and socio-economic factors through questionnaires, and acquired birth weight through data linkage. We regressed lung function against ethnicity and candidate predictors defined a priori using linear regression, and used penalised regression to examine a wider range of factors. We reviewed the implications of our findings for the feasibility of a larger study.

Results

There was a similar parental socio-economic environment and no difference in birth weight between the two ethnic groups, but the ethnic difference in FVC adjusted for sex, age, height, demi-span, father’s occupation, birth weight, maternal educational attainment and maternal upbringing was 0.81L (95%CI: -1.01 to -0.54L). Difference in body proportions did not explain the ethnic differences although parental immigration was an important predictor of FVC independent of ethnic group. Participants were comfortable with study procedures and we were able to link birth weight data to clinical measurements.

Conclusion

Studies of ethnic disparities in lung function among young adults are feasible. Future studies should recruit a socially more diverse sample and investigate the role of markers of acculturation in explaining such differences.

Life course socioeconomic adversities and 10-year risk of cardiovascular disease: cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health

OBJECTIVES

To investigate whether life course exposure to adverse socioeconomic positions (SEP) as well as maintaining a low SEP or decreasing the SEP intra- and intergeneration was associated with an increased 10-year cardiovascular disease (CVD) risk predicted by the Framingham Risk Score.

METHODS

This is a cross-sectional analysis of baseline data (2008-2010) of 13,544 active workers from ELSA-Brasil cohort. Maternal education, leg length, social class of first occupation and education were used to evaluate childhood, youth and adulthood SEP.

RESULTS

After considering adulthood SEP, exposure to early-life low SEP remained associated with an increased 10-year CVD risk. The 10-year CVD risk also rose as the number of exposures to low SEP throughout life increased. Compared to individuals in high-stable intragenerational trajectory, those in upward, downward, or stable low trajectory presented higher 10-year CVD risk. Increasing individuals' SEP over generation showed no increased risk of 10-year CVD risk compared to individuals in high-stable trajectory.

CONCLUSIONS

Childhood may be a critical period for exposures to social adversities. Life course low SEP may also affect the 10-year CVD risk via accumulation of risk and social mobility.

Growth in Total Height and Its Components and Cardiometabolic Health in Childhood

BACKGROUND

Short stature or short legs is associated with cardiometabolic disease. Few studies have addressed this issue in children, incorporated repeated measures, or studied modern cohorts.

METHODS

We examined if change in total height, leg length and trunk length between two time points from early (median: 3.2 years) to mid-childhood (median: 7.7 years), with and without adjustment for concurrent change in adiposity (subscapular plus triceps skinfold thickness), was associated with mid-childhood cardiometabolic risk in 315 boys and 295 girls from Project Viva. The main outcome was a cardiometabolic risk score based on sex-specific internal z-scores for systolic blood pressure, waist circumference, homeostatic model assessment of insulin resistance, triglycerides and high-density lipoprotein-cholesterol.

RESULTS

Mean (SD) total height was 97.9 (4.5) cm in boys and 97.1 (4.7) cm in girls in early childhood and 129.1 (7.2) cm in boys and 128.3 (7.9) cm in girls in mid-childhood. Trunk length constituted about half of total height. In linear regression models adjusted for parental anthropometry and socio-demographics, faster growth in total height, leg length and particularly trunk length, were associated with higher cardiometabolic risk in mid-childhood. Per 1 cm annual increase in trunk length, the cardiometabolic risk score was 0.23 z-score (95% confidence interval [CI] 0.08, 0.39) higher among boys and 0.47 z-score (95% CI 0.33, 0.60) higher among girls. Estimates were attenuated after adjusting for adiposity (boys: 0.03 z-score, 95% CI -0.11, 0.18; girls: 0.32 z-score, 95% CI 0.19, 0.45).

CONCLUSION

Rapid linear growth, particularly in trunk length, was associated with higher cardiometabolic risk in childhood, which was explained by relationships of linear growth with adiposity in boys, but only partly in girls.

Chronic disease outcomes after severe acute malnutrition in Malawian children (ChroSAM): a cohort study

BACKGROUND

Tackling severe acute malnutrition (SAM) is a global health priority. Heightened risk of non-communicable diseases (NCD) in children exposed to SAM at around 2 years of age is plausible in view of previously described consequences of other early nutritional insults. By applying developmental origins of health and disease (DOHaD) theory to this group, we aimed to explore the long-term effects of SAM.

METHODS

We followed up 352 Malawian children (median age 9·3 years) who were still alive following SAM inpatient treatment between July 12, 2006, and March 7, 2007, (median age 24 months) and compared them with 217 sibling controls and 184 age-and-sex matched community controls. Our outcomes of interest were anthropometry, body composition, lung function, physical capacity (hand grip, step test, and physical activity), and blood markers of NCD risk. For comparisons of all outcomes, we used multivariable linear regression, adjusted for age, sex, HIV status, and socioeconomic status. We also adjusted for puberty in the body composition regression model.

FINDINGS

Compared with controls, children who had survived SAM had lower height-for-age Z scores (adjusted difference vs community controls 0·4, 95% CI 0·6 to 0·2, p=0·001; adjusted difference vs sibling controls 0·2, 0·0 to 0·4, p=0·04), although they showed evidence of catch-up growth. These children also had shorter leg length (adjusted difference vs community controls 2·0 cm, 1·0 to 3·0, p<0·0001; adjusted difference vs sibling controls 1·4 cm, 0·5 to 2·3, p=0·002), smaller mid-upper arm circumference (adjusted difference vs community controls 5·6 mm, 1·9 to 9·4, p=0·001; adjusted difference vs sibling controls 5·7 mm, 2·3 to 9·1, p=0·02), calf circumference (adjusted difference vs community controls 0·49 cm, 0·1 to 0·9, p=0·01; adjusted difference vs sibling controls 0·62 cm, 0·2 to 1·0, p=0·001), and hip circumference (adjusted difference vs community controls 1·56 cm, 0·5 to 2·7, p=0·01; adjusted difference vs sibling controls 1·83 cm, 0·8 to 2·8, p<0·0001), and less lean mass (adjusted difference vs community controls -24·5, -43 to -5·5, p=0·01; adjusted difference vs sibling controls -11·5, -29 to -6, p=0·19) than did either sibling or community controls. Survivors of SAM had functional deficits consisting of weaker hand grip (adjusted difference vs community controls -1·7 kg, 95% CI -2·4 to -0·9, p<0·0001; adjusted difference vs sibling controls 1·01 kg, 0·3 to 1·7, p=0·005,)) and fewer minutes completed of an exercise test (sibling odds ratio [OR] 1·59, 95% CI 1·0 to 2·5, p=0·04; community OR 1·59, 95% CI 1·0 to 2·5, p=0·05). We did not detect significant differences between cases and controls in terms of lung function, lipid profile, glucose tolerance, glycated haemoglobin A1c, salivary cortisol, sitting height, and head circumference.

INTERPRETATION

Our results suggest that SAM has long-term adverse effects. Survivors show patterns of so-called thrifty growth, which is associated with future cardiovascular and metabolic disease. The evidence of catch-up growth and largely preserved cardiometabolic and pulmonary functions suggest the potential for near-full rehabilitation. Future follow-up should try to establish the effects of puberty and later dietary or social transitions on these parameters, as well as explore how best to optimise recovery and quality of life for survivors.

FUNDING

The Wellcome Trust.

Trajectories of Unhealthy Behaviors in Midlife and Risk of Disability at Older Ages in the Whitehall II Cohort Study

BACKGROUND

Most of the evidence on the association between unhealthy behaviors and disability comes from studies in the elderly, where reverse causation and selection bias may distort associations; thus, studies based on midlife trajectories of health behaviors are needed. We examined the association of trajectories of four health behaviors (physical activity, fruit and vegetable consumption, smoking, alcohol), starting in midlife and over 20 years, with subsequent disability risk in early old age (range = 54-84 years) in the Whitehall II cohort study.

METHODS

Disability was assessed three times over 3 years. A hierarchical disability indicator was constructed; participants were considered disabled if they reported difficulties with mobility and instrumental activities of daily living or with mobility and instrumental and basic activities of daily living. Behavior trajectories were defined using group-based trajectory models. Multivariable generalized estimating equations logistic models were used to examine their independent associations with disability.

RESULTS

Of 6,825 participants, 19.2% reported being disabled at least once. In mutually adjusted models, participants with persistent inactivity or declining physical activity, recent ex- or current smokers, and persistent/recent abstainers or persistent heavy drinkers had a higher disability risk, whereas fruit and vegetable consumption was not associated with disability. Disability risk increased progressively with the number of unhealthy behavior trajectories: the odds ratio of disability for 2-3 unhealthy trajectories was 2.69 (95% confidence interval = 2.26-3.19); these associations remained after adjustment for a wide range of covariates.

CONCLUSIONS

Unhealthy behavior trajectories in midlife are associated with greater disability risk later in life.

A life course approach to cardiovascular aging

A life course approach in epidemiology investigates the biological, behavioral and social pathways that link physical and social exposures and experiences during gestation, childhood, adolescence and adult life, and across generations, to later-life health and disease risk. We illustrate how a life course approach has been applied to cardiovascular disease, highlighting the evidence in support of the early origins of disease risk. We summarize how trajectories of cardiometabolic risk factors change over the life course and suggest that understanding underlying 'normal' or 'healthy' trajectories and the characteristics that drive deviations from such trajectories offer the potential for early prevention and for identifying means of preventing future disease.

Detection of Outliers Due to Participants' Non-Adherence to Protocol in a Longitudinal Study of Cognitive Decline

Background

Participants’ non adherence to protocol affects data quality. In longitudinal studies, this leads to outliers that can be present at the level of the population or the individual. The purpose of the present study is to elaborate a method for detection of outliers in a study of cognitive ageing.

Methods

In the Whitehall II study, data on a cognitive test battery have been collected in 1997-99, 2002-04, 2007-09 and 2012-13. Outliers at the 2012-13 wave were identified using a 4-step procedure: (1) identify cognitive tests with potential non-adherence to protocol, (2) choose a prediction model between a simple model with socio-demographic covariates and one that also includes health behaviours and health measures, (3) define an outlier using a studentized residual, and (4) study the impact of exclusion of outliers by estimating the effect of age and diabetes on cognitive decline.

Results

5516 participants provided cognitive data in 2012-13. Comparisons of rates of annual decline over the first three and all four waves of data suggested outliers in three of the 5 tests. Mean residuals for the 2012-13 wave were larger for the basic compared to the more complex prediction model (all p<0.001), leading us to use the latter for the identification of outliers. Residuals greater than two standard deviation of residuals identified approximately 7% of observations as being outliers. Removal of these observations from the analyses showed that both age and diabetes had associations with cognitive decline similar to that observed with the first three waves of data; these associations were weaker or absent in non-cleaned data.

Conclusions

Identification of outliers is important as they obscure the effects of known risk factor and introduce bias in the estimates of cognitive decline. We showed that an informed approach, using the range of data collected in a longitudinal study, may be able to identify outliers.

Structural and functional measures of social relationships and quality of life among older adults: does chronic disease status matter?

PURPOSE

To evaluate the relative importance of structural and functional social relationships for quality of life (QoL) and the extent to which diagnosed chronic disease modifies these associations.

METHODS

Multivariate linear regression was used to investigate time-lagged associations between structural and functional measures of social relationships and QoL assessed 5 years apart by CASP-19, in 5925 Whitehall II participants (mean age 61, SD 6.0). Chronic disease was clinically verified coronary heart disease, stroke, diabetes or cancer.

RESULTS

Social relationships-QoL associations were consistent across disease status (P-values for interaction: 0.15-0.99). Larger friend network (β = 1.9, 95% CI 1.5-2.3), having a partner (β = 1.2, 95% CI 0.5-1.7), higher confiding support (β = 2.2, 95% CI 1.8-2.7) and lower negative aspects of close relationships (β = 3.3, 95% CI 2.8-3.8) were independently related to improved QoL in old age. The estimated difference in QoL due to social relationships was equivalent to up to 0.5 SD of the CASP-19 score and was stronger than the effect of chronic disease (coronary heart disease β = 2.0, 95% CI 1.4-2.6).

CONCLUSIONS

We found that beneficial aspects of social relationships in relation to QoL were, in order of importance: avoiding negative aspects of close relationships, having confiding support, having a wide network of friends and having a partner. These associations were not modified by chronic disease. Thus, despite inevitable physical deterioration, we may be able to enhance a satisfying late life by optimizing our social relationships.

Association between adult height and tooth loss in a representative sample of Koreans

OBJECTIVES

Evidence suggests that taller individuals have better health than that of shorter individuals. However, evidence for links to tooth loss is scarce. The aim of this study was to examine the association between adult height and tooth loss and to examine the roles of covariates in explaining the association in different birth cohorts in Korea.

METHODS

Using data from the Fourth and Fifth Korea National Health and Nutritional Examination Survey (KNHANES IV and V), the subjects were grouped into two birth cohorts based on their historical context: born from 1920 to 1945 and 1946 to 1962. The dependent variables were loss of 8 or more teeth and total tooth loss (edentulism), while the independent variable was the height quartile. Demographic factors (survey year, age, and gender), early childhood/adult socioeconomic status (SES) (father's education, own education, income, and place of residence), health behaviors (cigarette smoking, binge drinking, frequency of toothbrushing, and regular dental visit), and health problems (diabetes and hypertension) were included in a series of analytical models.

RESULTS

The survey year-, age-, and gender-adjusted prevalence ratios (PR) of the loss of 8 or more teeth for the shortest quartile were 1.23 (95% confidence intervals, CI: 1.13-1.35) for the 1920-1945 birth cohorts and 1.39 (95% CI: 1.20-1.62) for the 1946-1962 birth cohorts. The PRs for edentulousness were 1.64 (95% CI: 1.34-2.02) for the 1920-1945 birth cohorts and 2.26 (95% CI: 1.31-3.91) for the 1946-1962 birth cohorts. These associations were moderately attenuated after adjusting for own education but still significant in the fully adjusted models. After full adjustment for the covariates, those in the shortest height quartiles in the relatively young birth cohorts (1946-1962 birth cohorts) had a 1.93 (95% CI: 1.09-3.43) times greater prevalence of edentulism than that of their tallest counterparts.

CONCLUSIONS

Given that adult height reflects early-life conditions, independent associations between height and tooth loss support the view that early-life circumstances significantly influence oral health outcomes in later life.

Birth weight and risk factors for cardiovascular disease and type 2 diabetes in US children and adolescents: 10 year results from NHANES

Previous studies have shown that birth weight and other birth characteristics may be associated with risk for type 2 diabetes and cardiovascular disease (CVD) later in life; however, results using large US national survey data are limited. Our goal was to determine the aforementioned associations using nationally representative data. We studied children and adolescents 6-15 years using data from the National Health and Nutrition Examination Survey cycles 2001-2010. Survey and examination data included demographic and early childhood characteristics, current health status, physical activity information, anthropometric measurements, dietary data (total energy, saturated fat, sodium, and sugar intakes), biomarkers related to selected risk factors of CVD [systolic blood pressure (SBP), plasma C-reactive protein (CRP) and lipid profiles], and type 2 diabetes [fasting glucose, insulin, and homeostasis model assessment (HOMA)]. Birth weight (proxy-reported) was inversely associated with SBP among girls; SBP levels increased 1.4 mmHg for each 1,000 g decrease in birth weight (p = 0.003) after controlling for potential confounders. Birth weight was not associated with levels of CRP or lipid profiles across the three racial groups. In addition, birth weight was inversely related to levels of fasting insulin and HOMA among non-Hispanic Whites; for each 1,000 g decrease in birth weight, fasting insulin levels increased 9.1% (p = 0.007) and HOMA scores increased 9.8% (p = 0.007). Birth weight was inversely associated with the levels of SBP, fasting insulin, and HOMA. These results support a role for birth weight, independent of the strong effects of current body weight status, in increasing risk for CVD and type 2 diabetes.

Association between leg length-to-height ratio and metabolic syndrome in Chinese children aged 3 to 6 years

Objective

The aim of this study is to investigate the association between leg-length-to-height ratio (LLHR) and metabolic syndrome (MetS) among Chinese children.

Methods

1236 children (619 obese and 617 nonobese children) aged 3–6 years participated in a cross-sectional survey in 2005 in Tianjin, China. Information on body adiposity, metabolic traits, and related covariates was obtained using a standardized protocol. LLHR was calculated as the ratio of leg length to stature.

Results

In the multivariable logistic regression analyses, compared with those in the lowest quartile, odds ratios (OR) and 95% confidence intervals (CI) of MetS among children in the second through the highest quartiles of LLHR Z-score were 0.89 (95% CI, 0.64–1.25), 0.45 (95% CI, 0.32–0.63), and 0.37 (95% CI, 0.26–0.53), respectively, (P_{for trend} < 0.0001 across LLHR Z-score quartiles). Compared with children with both higher levels of LLHR and lower levels of adipose indices, the corresponding ORs of MetS for those with both lower levels of LLHR and higher levels of anthropometric indices were 4.51 (95% CI, 3.08–6.62) for BMI Z-score, 3.86 (95% CI, 2.60–5.73) for waist circumference, and 2.75 (95% CI, 1.85–4.10) for waist-to-hip ratio, respectively.

Conclusions

Greater LLHR is inversely associated with MetS in Chinese children.

•

Leg-length-to-height ratio (LLHR) is negatively associated with childhood obesity.

•

Greater LLHR is inversely associated with childhood metabolic syndrome (MetS).

•

LLHR and adiposity have a synergistic effect in relation to pediatric MetS.

Body composition, leg length and blood pressure in a rural Italian population: a test of the capacity-load model

BACKGROUND AND AIMS

Whereas adult weight or body mass index (BMI) are directly associated with blood pressure (BP), birth weight is inversely associated with BP. The scenario for height is more complex, as both tall and short stature have been associated with higher BP. We used a theoretical model treating sitting height (SH) and tissue masses (fat mass, lean mass) as components of metabolic load, and leg length (LL) as a marker of homeostatic metabolic capacity. We predicted that decreased capacity and increased load would be independently associated with increased BP..

METHODS AND RESULTS

Anthropometry, body composition (bio-electrical impedance analysis) and BP were measured in 601 adults (228 male) aged 20-91 years from three hill villages in southern Italy. Multiple regression analysis was used to investigate associations of body composition and anthropometry with BP. Adjusting for age, systolic BP (SBP) was associated with lean mass in males, and with adiposity in females, whereas diastolic BP (DBP) was associated with fat mass in both sexes. Associations of LL and SH with BP were in opposite directions. LL was inversely associated with SBP and DBP in males, with a similar trend evident in females. SH was directly associated with SBP and DBP in females, and with DBP in males.

CONCLUSIONS

Consistent with our theoretical model, metabolic load is associated with increased BP, though differently between the sexes, whereas metabolic capacity is independently associated with lower BP. Our findings suggest that early growth improves hemodynamic tolerance of high metabolic load in adulthood..

Birth weight and risk of coronary heart disease in adults: a meta-analysis of prospective cohort studies

Some studies have found a significant relationship between birth weight (BW) and the risk of coronary heart disease (CHD) in adulthood, but results were inconsistent. The purpose of this study was to characterize the association between BW and the risk of CHD in adults. Among 144 papers detected by our search, 27 papers provided data on the relationship between BW and CHD, of which 23 papers considered BW as a continuous variable, and 14 articles considered BW as a categorical variable for this meta-analysis. Based on 23 papers, the mean weighted estimate for the association between BW and the combined outcome of non-fatal and fatal CHD was 0.83 [95% confidence interval (CI), 0.80-0.86] per kilogram of BW (P<0.0001). Low birth weight (LBW<2500 g) was associated with increased risk of CHD [odds ratio (OR), 1.19; 95% confidence interval (CI), 1.11-1.27] compared with subjects with BW⩾2500 g. LBW, as compared with normal BW (2500-4000 g), was associated with increased risk of CHD (OR, 1.16; 95% CI, 1.08-1.25). High birth weight (HBW⩾4000 g) was associated with decreased risk of CHD (OR, 0.89; 95% CI, 0.81-0.98) compared with subjects with BW<4000 g. In addition, there was an indication (not quite significant) that HBW was associated with a lower risk of CHD (OR, 0.89; 95% CI, 0.79-1.01), as compared with normal BW. No significant evidence of publication bias was present. These results suggest that LBW is significantly associated with increased risk of CHD and a 1 kg higher BW is associated with a 10-20% lower risk of CHD.

Bidirectional association between mental health and physical activity in older adults: Whitehall II prospective cohort study

OBJECTIVE

To investigate longitudinal and bidirectional associations between mental health and physical activity from midlife into old age.

METHODS

Analysis was based on data from 6909 participants (aged 45 to 69 in 1997/99) from the Whitehall II cohort in the UK. Latent growth curve analysis examined possible bidirectional associations between the SF-36 Mental Component Summary and weekly physical activity measured at three time-points over ten years.

RESULTS

Mental health and physical activity were associated at baseline (β=0.17, 95% CI 0.13, 0.21) and associations persisted into old age. In the latent growth curve model, both mental health and physical activity increased and their rates of change 'moved together' over time (β=0.24, 95% CI 0.11, 0.37). Relatively high baseline levels of either variable were associated with slightly slower increases in the other outcome (β=-0.02, 95% CI -0.03, -0.01; β=-0.07, 95% CI -0.11, -0.13), which are thought to reflect regression to the mean. However, those who started high on either variable remained the most advantaged at end of follow-up.

CONCLUSIONS

From midlife to old age, greater physical activity is associated with better mental health and vice versa. These findings suggest persistent longitudinal and bidirectional associations between physical activity and mental health.

Relationships between neonatal weight, limb lengths, skinfold thicknesses, body breadths and circumferences in an Australian cohort

Background

Low birth weight has been consistently associated with adult chronic disease risk. The thrifty phenotype hypothesis assumes that reduced fetal growth impacts some organs more than others. However, it remains unclear how birth weight relates to different body components, such as circumferences, adiposity, body segment lengths and limb proportions. We hypothesized that these components vary in their relationship to birth weight.

Methods

We analysed the relationship between birth weight and detailed anthropometry in 1270 singleton live-born neonates (668 male) from the Mater-University of Queensland Study of Pregnancy (Brisbane, Australia). We tested adjusted anthropometry for correlations with birth weight. We then performed stepwise multiple regression on birth weight of: body lengths, breadths and circumferences; relative limb to neck-rump proportions; or skinfold thicknesses. All analyses were adjusted for sex and gestational age, and used logged data.

Results

Circumferences, especially chest, were most strongly related to birth weight, while segment lengths (neck-rump, thigh, upper arm, and especially lower arm and lower leg) were relatively weakly related to birth weight, and limb lengths relative to neck-rump length showed no relationship. Skinfolds accounted for 36% of birth weight variance, but adjusting for size (neck-rump, thigh and upper arm lengths, and head circumference), this decreased to 10%. There was no evidence that heavier babies had proportionally thicker skinfolds.

Conclusions

Neonatal body measurements vary in their association with birth weight: head and chest circumferences showed the strongest associations while limb segment lengths did not relate strongly to birth weight. After adjusting for body size, subcutaneous fatness accounted for a smaller proportion of birth weight variance than previously reported. While heavier babies had absolutely thicker skinfolds, this was proportional to their size. Relative limb to trunk length was unrelated to birth weight, suggesting that limb proportions at birth do not index factors relevant to prenatal life.

Impact of size at birth and prematurity on adult anthropometry in 4744 middle-aged Danes - The Inter99 study

Low birth weight is related to increased risk of developing cardiovascular disease and type 2 diabetes in adult life. Since obesity is closely associated with type 2 diabetes and cardiovascular disease, the relationship between size at birth and adult anthropometry is of interest as a mediator of the relationship between birth weight and metabolic diseases. The aim of this study was, therefore, to examine the effect of size at birth and prematurity on measures of adult anthropometry taking adult socio-economic status and lifestyle variables into account. Midwife records with information on mother's age and parity as well as weight, length and maturity at birth were traced in 4744 Danes born between 1939 and 1970. Measures of adult anthropometry (weight, height, body mass index (BMI), waist circumference, hip circumference and waist/hip ratio) had previously been recorded together with information on socio-economic factors, lifestyle and parental diabetes status. Mother's age, parity and diabetes status were associated with offspring birth weight. Size at birth was positively associated with adult height and weight, but only weakly associated with BMI and not associated with waist/hip ratio when adjusted for socio-economic and lifestyle factors. Infants born preterm were less growth restricted at birth and grew to be taller and heavier compared with term infants born small for gestational age. Altogether, this study does not find evidence that obesity or a central fat distribution is mediating the relationship between low birth weight and risk of cardiovascular disease or type 2 diabetes in later life.

Alcohol consumption and cognitive decline in early old age

Objective:

To examine the association between alcohol consumption in midlife and subsequent cognitive decline.

Methods:

Data are from 5,054 men and 2,099 women from the Whitehall II cohort study with a mean age of 56 years (range 44–69 years) at first cognitive assessment. Alcohol consumption was assessed 3 times in the 10 years preceding the first cognitive assessment (1997–1999). Cognitive tests were repeated in 2002–2004 and 2007–2009. The cognitive test battery included 4 tests assessing memory and executive function; a global cognitive score summarized performances across these tests. Linear mixed models were used to assess the association between alcohol consumption and cognitive decline, expressed as z scores (mean = 0, SD = 1).

Results:

In men, there were no differences in cognitive decline among alcohol abstainers, quitters, and light or moderate alcohol drinkers (<20 g/d). However, alcohol consumption ≥36 g/d was associated with faster decline in all cognitive domains compared with consumption between 0.1 and 19.9 g/d: mean difference (95% confidence interval) in 10-year decline in the global cognitive score = −0.10 (−0.16, −0.04), executive function = −0.06 (−0.12, 0.00), and memory = −0.16 (−0.26, −0.05). In women, compared with those drinking 0.1 to 9.9 g/d of alcohol, 10-year abstainers showed faster decline in the global cognitive score (−0.21 [−0.37, −0.04]) and executive function (−0.17 [−0.32, −0.01]).

Conclusions:

Excessive alcohol consumption in men (≥36 g/d) was associated with faster cognitive decline compared with light to moderate alcohol consumption.

Components of height and blood pressure in childhood

BACKGROUND

In children being taller is associated with higher blood pressure (BP), but few studies have divided height into its components: trunk and leg length. We examined the associations of total height, trunk length and leg length with systolic BP (SBP), diastolic BP (DBP) and pulse pressure (PP) at early childhood and mid-childhood visits, as well as change between the two visits.

METHODS

We obtained five measures of SBP and DBP at the early childhood visit (N = 1153, follow-up rate = 54%) and at the mid-childhood visit (N = 1086, follow-up rate = 51%) respectively, in Project Viva, a US cohort study. We measured total height and sitting height (a measure of trunk length that includes head and neck) and calculated leg length as the difference between the two. Using mixed models, we adjusted the cross-sectional analyses for leg length when trunk length was the exposure of interest, and vice versa. We also adjusted for maternal race/ethnicity, child age, sex, overall adiposity and BP measurement conditions.

RESULTS

At the mid-childhood visit, total height was positively associated with SBP [0.34 (0.24; 0.45) mmHg/cm] but not with DBP [0.07 (-0.003; 0.15)]. In models examining trunk and leg length separately, each was positively associated with SBP [0.72 (0.52; 0.92) and 0.33 (0.16; 0.49) respectively]. In a fully adjusted model with both leg and trunk length, only trunk length remained associated with BP. For a given leg length, a 1-cm increment in trunk length was associated with a 0.63-mmHg (0.42; 0.83) higher SBP and a 0.17-mmHg (0.02; 0.31) higher DBP. For a given trunk length, however, the associations of leg length with SBP [0.13 (-0.03; 0.30)] and with DBP [0.002 (-0.11; 0.12)] were null. These patterns were similar at the early childhood visit.

CONCLUSIONS

Children with greater trunk lengths have higher BPs, perhaps because of the additional pressure needed to overcome gravity to perfuse the brain.

Association of walking speed in late midlife with mortality: results from the Whitehall II cohort study

Slow walking speed is associated with increased mortality in the elderly, but it is unknown whether a similar association is present in late midlife. Our aim was to examine walking speed in late midlife as a predictor of mortality, as well as factors that may explain this association. Data are drawn from the Whitehall II longitudinal cohort study of British civil servants. The analyses are based on 6,266 participants (29% women; mean age = 61 years, SD = 6) for whom "walking speed at usual pace" was measured over 8 ft (2.44 m) at baseline. Participants were followed for all-cause and cause-specific mortalities during a mean of 6.4 (SD = 0.8) years. During this period, 227 participants died. Participants in the bottom sex-specific third of walking speed (men, <1.26 m/s; women, <1.09 m/s) had an increased risk of death compared to those in the middle and top thirds (age- and sex-adjusted hazard ratio = 1.89, 95% confidence interval (CI) = 1.45-2.46), with no evidence of effect modification by age or sex (interactions, P ≥ 0.40). The association between walking speed and mortality was partially explained by baseline inflammatory markers (percentage reduction of the association 22.8%), height and body mass index (16.6%), chronic diseases (14.0%), and health behaviors (13.4%). Together these and other baseline factors (socioeconomic status, cardiovascular risk factors, cognitive function) explained 48.5% of the association (adjusted hazard ratio = 1.39, 95% CI = 1.04-1.84). In conclusion, walking speed measured in late midlife seems to be an important marker of mortality risk; multiple factors, in particular inflammatory markers, partially explain this association.

Influence of individual and combined healthy behaviours on successful aging

BACKGROUND

Increases in life expectancy make it important to remain healthy for as long as possible. Our objective was to examine the extent to which healthy behaviours in midlife, separately and in combination, predict successful aging.

METHODS

We used a prospective cohort design involving 5100 men and women aged 42-63 years. Participants were free of cancer, coronary artery disease and stroke when their health behaviours were assessed in 1991-1994 as part of the Whitehall II study. We defined healthy behaviours as never smoking, moderate alcohol consumption, physical activity (≥ 2.5 h/wk moderate physical activity or ≥ 1 h/wk vigorous physical activity), and eating fruits and vegetables daily. We defined successful aging, measured over a median 16.3-year follow-up, as good cognitive, physical, respiratory and cardiovascular functioning, in addition to the absence of disability, mental health problems and chronic disease (coronary artery disease, stroke, cancer and diabetes).

RESULTS

At the end of follow-up, 549 participants had died and 953 qualified as aging successfully. Compared with participants who engaged in no healthy behaviours, participants engaging in all 4 healthy behaviours had 3.3 times greater odds of successful aging (95% confidence interval [CI] 2.1-5.1). The association with successful aging was linear, with the odds ratio (OR) per increment of healthy behaviour being 1.3 (95% CI 1.2-1.4; population-attributable risk for 1-4 v. 0 healthy behaviours 47%). When missing data were considered in the analysis, the results were similar to those of our main analysis.

INTERPRETATION

Although individual healthy behaviours are moderately associated with successful aging, their combined impact is substantial. We did not investigate the mechanisms underlying these associations, but we saw clear evidence of the importance of healthy behaviours for successful aging.

Impact of smoking on cognitive decline in early old age: the Whitehall II cohort study

CONTEXT

Smoking is a possible risk factor for dementia, although its impact may have been underestimated in elderly populations because of the shorter life span of smokers.

OBJECTIVE

To examine the association between smoking history and cognitive decline in the transition from midlife to old age.

DESIGN

Cohort study.

SETTING

The Whitehall II study. The first cognitive assessment was in 1997 to 1999, repeated over 2002 to 2004 and 2007 to 2009.

PARTICIPANTS

Data are from 5099 men and 2137 women in the Whitehall II study, mean age 56 years (range, 44-69 years) at the first cognitive assessment.

MAIN OUTCOME MEASURES

The cognitive test battery was composed of tests of memory, vocabulary, executive function (composed of 1 reasoning and 2 fluency tests), and a global cognitive score summarizing performance across all 5 tests. Smoking status was assessed over the entire study period. Linear mixed models were used to assess the association between smoking history and 10-year cognitive decline, expressed as z scores.

RESULTS

In men, 10-year cognitive decline in all tests except vocabulary among never smokers ranged from a quarter to a third of the baseline standard deviation. Faster cognitive decline was observed among current smokers compared with never smokers in men (mean difference in 10-year decline in global cognition=-0.09 [95% CI, -0.15 to -0.03] and executive function=-0.11 [95% CI, -0.17 to -0.05]). Recent ex-smokers had greater decline in executive function (-0.08 [95% CI, -0.14 to -0.02]), while the decline in long-term ex-smokers was similar to that among never smokers. In analyses that additionally took dropout and death into account, these differences were 1.2 to 1.5 times larger. In women, cognitive decline did not vary as a function of smoking status.

CONCLUSIONS

Compared with never smokers, middle-aged male smokers experienced faster cognitive decline in global cognition and executive function. In ex-smokers with at least a 10-year cessation, there were no adverse effects on cognitive decline.

Low birth weight does not predict the ontogeny of relative leg length of infants and children: an allometric analysis of the NHANES III sample

Previous research links both low birth weight (LBW) and relative leg length (RLL) to a similar set of adult pathologies, including type II diabetes, coronary vascular disease, and some cancers. Historically, LBW has been frequently used as a broad indicator of the quality of the intrauterine environment, while RLL has been considered a sensitive measure of childhood environmental quality. While these observations have been taken to suggest that these measures reflect independent exposures at different life-stages, their mutual association with a similar set of later pathologies makes this assumption less certain than it may have previously seemed. Nationally representative data from the Third National Health and Nutrition Examination Survey (NHANES III) are used to test the hypothesis that LBW predicts reductions in the development of leg length relative to stature. After controls for important socioeconomic exposures that might confound measurement of such a relationship, we find statistical and biological evidence that variation in birth weight and variation in the development of leg length relative to stature (RLL) are independent. The results suggest that these two measures may represent independent information on prenatal and postnatal environmental quality.

Associations of adult height and its components with mortality: a report from cohort studies of 135,000 Chinese women and men

BACKGROUND

Although several studies have evaluated the relationship between adult height and mortality, their results have not been entirely consistent. Little is known about components of adult height in relation to mortality, particularly in developing countries.

METHODS

We examined the association of adult height and its components (leg and trunk length) with mortality using data from 74 869 Chinese women and 61,333 men in the Shanghai Women's (1996-2008) and Men's (2002-2008) Health Studies. Anthropometric measurements, including standing and sitting height and weight, were taken at baseline by trained interviewers according to a standard protocol. Deaths were ascertained by biennial home visits and linkage with the vital statistics registry. Cox regression models were used to evaluate the associations.

RESULTS

Neither height nor its components were associated with all-cause mortality. Height and, less consistently, its components were positively associated with cancer mortality, but inversely associated with cardiovascular disease (CVD) mortality. Hazard ratios (HRs) [95% confidence intervals (CIs)] for cancer mortality per 1-SD increment in height, trunk and leg length were 1.06 (1.01-1.12), 1.07 (1.01-1.12) and 1.03 (0.98-1.08), respectively, in women, and 1.13 (1.05-1.22), 1.09 (1.00-1.19) and 1.10 (1.03-1.16), respectively, in men. The corresponding HRs for CVD mortality were 0.89 (0.84-0.95), 0.93 (0.87-0.99) and 0.91 (0.86-0.98) in women, and 0.93 (0.86-1.02), 0.89 (0.81-0.98) and 0.99 (0.92-1.06) in men.

CONCLUSIONS

Our results suggest that different mechanisms may be involved in linking height and its components with cancer and CVD mortality.

Birth size and adult size in same-sex siblings discordant for fetal growth in the Early Determinants of Adult Health study

Many studies have reported on relations between birth size and adult size but the findings to date are hard to compare due to the lack of uniform measures across studies. Interpretation of findings is also hampered by potential confounding by ethnic, socioeconomic and family factors. The purpose of this study is to explore these relationships in a comprehensive fashion, with multiple measures of birth size and adult size, using same-sex sibling controls discordant in birth weight to address potential confounding at the family level. Study subjects include pregnant women enrolled during 1959-1966 in the Child Health and Development Study in Oakland, CA and the Boston, MA, and providence, RI, sites of the Collaborative Perinatal Project in New England, currently combined into the New England Family Study. We assessed 392 offspring (mean age 43 years), the great majority as sibships as available. Our analyses confirm the positive association between birth weight and adult length reported in other studies, with a change in adult height of 1.25 cm (95% CI: 0.79 to 1.70 cm) for each quintile change in standardized birth weight. No associations were seen between birth weight and adult fatness for which findings in other studies are highly variable. As adult weight is likely to reflect recent variations in the adult nutritional environment rather than the early environment, it may be more useful for studies of birth size and adult size to focus on adult length rather than weight measures in evaluating the role of early influences on adult health.

Effect of intensity and type of physical activity on mortality: results from the Whitehall II cohort study

OBJECTIVES

We examined the association of intensity and type of physical activity with mortality.

METHODS

We assessed the duration of physical activity by intensity level and type in 7456 men and women from the Whitehall II Study by questionnaire in 1997-1999 (mean ±SD age = 55.9 ± 6.0 years) and 5 years later. All-cause mortality was assessed until April 2009.

RESULTS

A total of 317 participants died during the mean follow-up of 9.6 years (SD = 2.7). Reporting at least 1 hour per week of moderate activity was associated with a 33% (95% confidence interval [CI] = 14%, 45%) lower risk of mortality compared with less than 1 hour. For all physical activity types examined, except housework, a duration of physical activity greater than 0 (≥ 3.5 hours for walking) was associated with lower mortality in age-adjusted analyses, but only the associations with sports (hazard ratio [HR] = 0.71; 95% CI = 0.56, 0.91) and do-it-yourself activity (HR = 0.68; 95% CI = 0.53, 0.98) remained in fully adjusted analyses.

CONCLUSIONS

It is important to consider both intensity and type of physical activity when examining associations with mortality.

Why socially deprived populations have a faster resting heart rate: impact of behaviour, life course anthropometry, and biology--the RECORD Cohort Study

Although studies have shown that resting heart rate (RHR) is predictive of cardiovascular morbidity/mortality, few studies focused on the epidemiology and social aetiology of RHR. Using the RECORD Cohort Study (7158 participants, 2007-2008, Paris region, France), we investigated individual/neighbourhood socioeconomic variables associated with resting heart rate, and assessed which of a number of psychological factors (depression and stress), behaviour (sport-related energy expenditure, medication use, and alcohol, coffee, and tobacco consumption), life course anthropometric factors (body mass index, waist circumference, and leg length as a marker of childhood environmental exposures), and biologic factors (alkaline phosphatase and gamma-glutamyltransferase) contributed to the socioeconomic disadvantage-RHR relationship. Combining individual/neighbourhood socioeconomic factors in a socioeconomic score, RHR increased with socioeconomic disadvantage: +0.9 [95% credible interval (CrI): +0.2, +1.6], +1.8 (95% CrI: +1.0, +2.5), and +3.6 (95% CrI: +2.9, +4.4) bpm for the 3 categories reflecting increasing disadvantage, compared with the lowest disadvantage category. Twenty-one percent of the socioeconomic disadvantage-RHR relationship was explained by sport practise variables, 9% by waist circumference, 7% by gamma-glutamyltransferase, 5% by alkaline phosphatase, and 3% by leg length. Future research should further clarify the mechanisms through which socioeconomic disadvantage influences resting heart rate, as a pathway to social disparities in cardiovascular morbidity/mortality.

Sex-specific relationships between adiposity and anthropometric measures and carotid intima-media thickness in Koreans: the Healthy Twin Study

BACKGROUND/OBJECTIVES

Increased adiposity, shorter stature, shorter leg length and carotid intima-media thickening are associated with cardiovascular (CV) disease. This study aimed to evaluate the sex-specific phenotypic and genetic associations between adiposity and anthropometric measures and carotid intima-media thickness (IMT).

SUBJECTS/METHODS

We measured IMT at common carotid artery (CCA-IMT), carotid bifurcation and internal carotid artery (ICA-IMT) using B-mode ultrasound, and adiposity and anthropometric measures, including body mass index (BMI), height, leg length, waist circumference (WC), waist-to-hip ratio and percentage of body fat; we also assessed conventional CV risk factors among 706 Korean adults from the Healthy Twin Study. The associations were analyzed using quantitative genetic and linear mixed analyses.

RESULTS

In linear mixed analyses, BMI and WC had independent associations with the IMT at CCA-IMT and ICA-IMT and CCA-IMT, respectively, after adjusting for age and conventional CV risk factors in men. By comparison, in women, adiposity and anthropometric measures were associated with carotid IMT only before adjusting for the covariates. In men, there were significant genetic correlations between BMI and CCA-IMT (ρ(G)=0.32±0.11), BMI and ICA-IMT (ρ(G)=0.35±0.11) and WC and ICA-IMT (ρ(G)=0.32±0.13) after adjusting for covariates, whereas in women the cross-trait genetic correlations were no longer significant after adjusting for the covariates.

CONCLUSIONS

In this Korean twins and families, we found sex-specific associations between adiposity and anthropometric measures and the IMT at each segment of the carotid artery, and BMI and WC in men can be indicators predicting carotid intima-media thickening regardless of age and CV risk factors.

Is relative leg length a biomarker of childhood nutrition? Long-term follow-up of the Hyderabad Nutrition Trial

BACKGROUND

Relative leg length is frequently used as a biomarker of childhood nutrition in epidemiological studies, but evidence is lacking. We examined the association between supplemental nutrition in pregnancy and childhood and relative proportions of components of height in adolescence.

METHODS

In a community trial of nutritional supplementation, villages from adjacent administrative areas were selected to serve as intervention (n = 15) and control (n = 14) arms. In the intervention villages, balanced protein-calorie supplementation (2.51 MJ, 20 g protein) was offered daily to pregnant women and their offspring until the age of 6 years. Children born in the trial were re-examined 15 years later to assess components of height.

RESULTS

A total of 1165 adolescents (intervention: 654, 49% of trial participants; control: 511, 41% of trial participants) aged 13-18 years were examined. Supplemented children were 10 mm taller [95% confidence interval (CI): 1.4 to 18.7 mm], but almost all of the increase was in trunk length (9 mm, 95% CI: 2.6 to 15.4 mm). The age- and gender-adjusted β-coefficients for the association of nutritional supplementation with relative trunk, leg and lower leg lengths (expressed as standard deviation scores) were 0.26 (95% CI: 0.11 to 0.42), 0.08 (95% CI: -0.03 to 0.19) and 0.03 (95% CI: -0.08 to 0.15) respectively, thereby unsupportive of cephalocaudal gradient in growth.

CONCLUSIONS

In this nutritional supplementation trial in an undernourished population, we were unable to confirm relative leg length as a biomarker of childhood nutrition. Alternative explanations may underlie the reported associations between childhood conditions and relative leg length.

Height loss and future coronary heart disease in London: the Whitehall II study

BACKGROUND

Although several plausible biological mechanisms have been advanced for the association between greater physical stature and lower coronary heart disease (CHD) risk in prospective cohort studies, the importance of one of the principal artefactual explanations--reverse causality due to shrinkage--remains unresolved. To explore this issue, studies with repeat measurements of height are required, but, to date, such data have been lacking.

OBJECTIVE

To examine the possible relationship between height loss and future CHD.

METHODS

Data were analysed from the Whitehall II prospective cohort study of 3802 men and 1615 women who participated in a physical examination in 1985-8, had their height re-measured in 1997-9, and were then followed up for fatal and non-fatal CHD.

RESULTS

A mean follow-up of 7.4 years after the second height measurement gave rise to 69 CHD events in men and 18 in women. After adjustment for baseline CHD risk factors, greater loss of physical stature between survey and resurvey was associated with an increased risk of CHD in men (HR; 95% CI for a one SD increase: 1.24; 1.00 to 1.53) but not women (0.93; 0.58 to 1.50).

CONCLUSIONS

Reverse causality due to shrinkage may contribute to the inverse association between a single measurement of height and later CHD in other studies.

Why does lung function predict mortality? Results from the Whitehall II Cohort Study

The authors examined the extent to which socioeconomic position, behavior-related factors, cardiovascular risk factors, inflammatory markers, and chronic diseases explain the association between poor lung function and mortality in 4,817 participants (68.9% men) from the Whitehall II Study aged 60.8 years (standard deviation, 5.9), on average. Forced expiratory volume in 1 second (FEV(1)) was used to measure lung function in 2002-2004. A total of 139 participants died during a mean follow-up period of 6.4 years (standard deviation, 0.8). In a model adjusted for age and sex, being in the lowest tertile of FEV(1)/height(2) was associated with a 1.92-fold (95% confidence interval: 1.35, 2.73) increased risk of mortality compared with being in the top 2 tertiles. Once age, sex, and smoking history were taken into account, the most important explanatory factors for this association were inflammatory markers (21.3% reduction in the FEV(1)/height(2)-mortality association), coronary heart disease, stroke, and diabetes (11.7% reduction), and alcohol consumption, diet, physical activity, and body mass index (9.8% reduction). The contribution of socioeconomic position and cardiovascular risk factors was small (≤ 3.5% reduction). Taken together, these factors explained 32.5% of the association. Multiple pathways link lung function to mortality; these results show inflammatory markers to be particularly important.

Short stature is associated with coronary heart disease: a systematic review of the literature and a meta-analysis

AIMS

The aim of this study was to assess the relationship between short stature and coronary heart disease (CHD) morbidity and mortality.

METHODS AND RESULTS

We performed a systematic search from MEDLINE, PREMEDLINE, and All EBM Reviews as well as from a reference list of relevant articles. We used SPICO (Study design, Patient, Intervention, Control-intervention, Outcome) criteria. The methodological quality of studies was analysed by modified Borghoust criteria. From a total of 1907 articles, we selected 52 studies comprising population-based follow-up studies and patient cohorts followed after a CHD event, as well as case-control studies with height either as a continuous or categorical variable, totalling 3 012 747 individuals. The short ones were below 160.5 cm and tall ones over 173.9 cm on average. Among the shortest height category, the relative risks were 1.35 (95% CI 1.25-1.44) for all-cause mortality, 1.55 (1.37-1.74) for all cardiovascular disease (CVD) mortality, 1.49 (1.33-1.67) for CHD, and 1.52 (1.28-1.81) for myocardial infarction when compared with those within the highest height category. The mean relative risk was 1.46 (1.37-1.55). Short stature was associated with increased cardiovascular morbidity and mortality in both genders.

CONCLUSION

The relationship between short stature and CVD appears to be a real one. On the basis of comparison, adults within the shortest category had an approximately 50% higher risk of CHD morbidity and mortality than tall individuals.

Leg length, body proportion, and health: a review with a note on beauty

Decomposing stature into its major components is proving to be a useful strategy to assess the antecedents of disease, morbidity and death in adulthood. Human leg length (femur + tibia), sitting height (trunk length + head length) and their proportions, for example, (leg length/stature), or the sitting height ratio (sitting height/stature x 100), among others) are associated with epidemiological risk for overweight (fatness), coronary heart disease, diabetes, liver dysfunction and certain cancers. There is also wide support for the use of relative leg length as an indicator of the quality of the environment for growth during infancy, childhood and the juvenile years of development. Human beings follow a cephalo-caudal gradient of growth, the pattern of growth common to all mammals. A special feature of the human pattern is that between birth and puberty the legs grow relatively faster than other post-cranial body segments. For groups of children and youth, short stature due to relatively short legs (i.e., a high sitting height ratio) is generally a marker of an adverse environment. The development of human body proportions is the product of environmental x genomic interactions, although few if any specific genes are known. The HOXd and the short stature homeobox-containing gene (SHOX) are genomic regions that may be relevant to human body proportions. For example, one of the SHOX related disorders is Turner syndrome. However, research with non-pathological populations indicates that the environment is a more powerful force influencing leg length and body proportions than genes. Leg length and proportion are important in the perception of human beauty, which is often considered a sign of health and fertility.