Weight history from birth through childhood and youth in relation to adult lung function, in Danish juvenile obese and non-obese men

Can birth weight predict offspring's lung function in adult age? Evidence from two Swedish birth cohorts

BACKGROUND

Associations between birth weight (BW) and adult lung function have been inconsistent and limited to early adulthood. We aimed to study this association in two population-based cohorts and explore if BW, adjusted for gestational age, predicts adult lung function. We also tested adult lung function impairment according to the mis-match hypothesis-small babies growing big as adults.

METHODS

We included 3495 individuals (aged 46.4 ± 5.4 years) from the Malmo Preventive Project (MPP), Sweden, born between 1921 and 1949, and 1401 young to middle-aged individuals (aged 28.6 ± 6.7 years) from the Malmo Offspring Study (MOS) with complete data on BW and gestational age. Adult lung function (forced vital capacity [FVC], forced expiratory volume in one second [FEV1] and the FEV1/FVC-ratio) were analysed as level of impairment (z-score), using multiple linear and logistic regressions.

RESULTS

BW (z-score) did not predict adult lung function in MPP, whereas BW was a significant (p = 0.003) predictor of FEV1 following full adjustment in MOS. For every additional unit increase in BW, children were 0.77 (95% CI 0.65-0.92) times less likely to have impaired adult lung function (FEV1). Moreover, adults born with lower BW (< 3510 g) showed improved lung function (FEV1 and FEV1/FVC in MOS and MPP, respectively) if they achieved higher adult body weight.

CONCLUSIONS

Adults born with lower birth weight, adjusted for gestational age, are more likely to have impaired lung function, seen in a younger birth cohort. Postnatal growth pattern may, however, compensate for low birth weight and contribute to better adult lung function.

Assessment of lung function in successfully treated tuberculosis reveals high burden of ventilatory defects and COPD

Background

Burden, phenotype and risk-factors of lung function defects in successfully treated tuberculosis cases are unclear.

Methods

We performed spirometry with bronchodilators in new drug-sensitive adult (≥18 years) pulmonary tuberculosis cases during the 12 months following successful treatment in India. Airflow obstruction was defined as pre-bronchodilator FEV1/FVC<5^th percentile of Global Lung Initiative mixed-ethnicity reference (lower limit of normal [LLN]). Chronic obstructive pulmonary disease (COPD) was defined as post-bronchodilator FEV1/FVC<LLN among participants with obstruction. Restrictive spirometry pattern was defined as FVC<LLN among participants without obstruction. Multivariable logistic and linear regression was used to identify risk-factors for obstruction, restriction and low lung function despite successful treatment.

Results

Of the 172 participants included in the analysis, 82 (48%) were female, 22 (13%) had diabetes and 34 (20%) ever-smoked with a median (IQR) exposure of 3.5 (0.2–9.9) pack-years. Median (IQR) age and body-mass index (BMI) at enrollment was 32 (23–39) years and 18.1 (16.0–20.5) kg/m² respectively. Airflow obstruction was detected in 42 (24%) participants; of whom 9 (21%) responded to short-acting bronchodilators and 25 (56%) had COPD; and was associated with duration of illness prior to treatment (aOR = 1.32 per 30-days, 95%CI 1.04–1.68, p = 0.02). A restrictive spirometry pattern was detected in 89 (52%) participants and was associated with female sex (aOR = 3.73, 95%CI 1.51–9.17, p = 0.004) and diabetes (aOR = 4.06, 95%CI 1.14–14.42, p = 0.03). Higher HbA1c at treatment initiation was associated with greater odds of a restrictive spirometry pattern (aOR = 1.29 per unit higher HbA1c, 95%CI 1.04 to 1.60, p = 0.02).

Conclusion

We found a high burden of lung function defects and COPD in tuberculosis cases who successfully completed treatment. Screening for chronic lung diseases following treatment and linkage to respiratory health clinics should be included in the routine management plan of all tuberculosis cases in India, regardless of conventional COPD risk-factors such as older age and smoking.

Birth weight, early childhood growth and lung function in middle to early old age: 1946 British birth cohort

BACKGROUND

Findings from previous studies investigating the relationship between birth weight and adult lung function have been inconsistent, and data on birth weight and adult lung function decline are lacking. Few studies have investigated the relation between early childhood growth and adult lung function.

METHODS

FEV1 and FVC were measured at ages 43 years, 53 years and 60-64 years in the 1946 British birth cohort study. Multiple linear regression models were fitted to study associations with birth weight and weight gain at age 0-2 years. Multilevel models assessed how associations changed with age, with FEV1 and FVC as repeated outcomes.

RESULTS

3276 and 3249 participants were included in FEV1 and FVC analyses, respectively. In women, there was a decreasing association between birth weight and FVC with age. From the multilevel model, for every 1 kg higher birth weight, FVC was higher on average by 66.3 mL (95% CI 0.5 to 132) at 43 years, but significance was lost at 53 years and 60-64 years. Similar associations were seen with FEV1, but linear change (decline) from age 43 years lost statistical significance after full adjustment. In men, associations with birth weight were null in multilevel models. Higher early life weight gain was associated with higher FEV1 at age 43 years in men and women combined but not in each sex.

CONCLUSIONS

Birth weight is positively associated with adult lung function in middle age, particularly in women, but the association diminishes with age, potentially due to accumulating environmental influences over the life course.

Impact of childhood anthropometry trends on adult lung function

BACKGROUND

Poor fetal growth rate is associated with lower respiratory function; however, there is limited understanding of the impact of growth trends and BMI during childhood on adult respiratory function.

METHODS

The current study data are from the Mater-University of Queensland Study of Pregnancy birth cohort. Prospective data were available from 1,740 young adults who performed standard spirometry at 21 years of age and whose birth weight and weight, height, and BMI at 5, 14, and 21 years of age were available. Catch-up growth was defined as an increase of 0.67 Z score in weight between measurements. The impact of catch-up growth on adult lung function and the relationship between childhood BMI trends and adult lung function were assessed using regression analyses.

RESULTS

Lung function was higher at 21 years in those demonstrating catch-up growth from birth to 5 years (FVC, men: 5.33 L vs 5.54 L; women: 3.78 L vs 4.03 L; and FEV1, men: 4.52 L/s vs 4.64 L/s; women: 3.31 L/s vs 3.45 L/s). Subjects in the lowest quintile of birth (intrauterine growth retardation) also showed improved lung function if they had catch-up growth in the first 5 years of life. There was a positive correlation between increasing BMI and lung function at 5 years of age. However, in the later measurements when BMI increased into the obese category, a drop in lung function was observed.

CONCLUSIONS

These data show evidence for a positive contribution of catch-up growth in early life to adult lung function. However, if weight gain or onset of obesity occurs after 5 years of age, an adverse impact on adult lung function is noted.

Obesidade e testes de função pulmonar em crianças e adolescentes: uma revisão sistemática

OBJETIVO: Realizar uma revisão sistemática sobre os estudos observacionais que analisaram a relação entre os parâmetros espirométricos e a obesidade em crianças e adolescentes. FONTES DE DADOS: Os dados foram selecionados sem restrição de idioma, utilizando-se as bases de dados PubMed/Medline, Scopus, Lilacs e SciELO, sem data inicial até dezembro de 2010. Os descritores foram extraídos do Medical Subject Headings e incluíram "respiratory function tests" e "childhood obesity". SINTESE DOS DADOS: Por meio da estratégia de busca, 89 artigos foram encontrados, dos quais apenas cinco foram selecionados. Foram incluídos estudos observacionais com descrição dos parâmetros espirométricos e do índice de massa corpórea, sendo excluídos estudos com outros métodos de avaliação da função pulmonar, população não exclusiva de crianças/adolescentes e presença de comorbidades associadas à obesidade. Para avaliação da qualidade dos estudos utilizou-se a escala para estudos observacionais da Agency for Healthcare Research and Quality. Os estudos avaliaram a capacidade vital forçada e o volume expiratório forçado no primeiro segundo. Quatros artigos avaliaram também o fluxo expiratório forçado entre 25 e 75%, aquele em 50%, o pico de fluxo expiratório e a relação entre o volume expiratório forçado no primeiro segundo e a capacidade vital forçada. CONCLUSÕES: Os artigos mostram evidências significativas de associação entre a diminuição dos valores de capacidade vital forçada e volume expiratório forçado no primeiro segundo com a obesidade em crianças e adolescentes.

Early markers of adult obesity: a review

The purpose of this review was to evaluate factors in early childhood (≤5 years of age) that are the most significant predictors of the development of obesity in adulthood. Factors of interest included exposures/insults in the prenatal period, infancy and early childhood, as well as other socio-demographic variables such as socioeconomic status (SES) or birth place that could impact all three time periods. An extensive electronic and systematic search initially resulted in 8,880 citations, after duplicates were removed. Specific inclusion and exclusion criteria were set, and following two screening processes, 135 studies were retained for detailed abstraction and analysis. A total of 42 variables were associated with obesity in adulthood; however, of these, only seven variables may be considered as potential early markers of obesity based on the reported associations. Possible early markers of obesity included maternal smoking and maternal weight gain during pregnancy. Probable early markers of obesity included maternal body mass index, childhood growth patterns (early rapid growth and early adiposity rebound), childhood obesity and father's employment (a proxy measure for SES in many studies). Health promotion programmes/agencies should consider these factors as reasonable targets to reduce the risk of adult obesity.

Early markers of adult obesity: a review

The purpose of this review was to evaluate factors in early childhood (≤5 years of age) that are the most significant predictors of the development of obesity in adulthood. Factors of interest included exposures/insults in the prenatal period, infancy and early childhood, as well as other socio-demographic variables such as socioeconomic status (SES) or birth place that could impact all three time periods. An extensive electronic and systematic search initially resulted in 8,880 citations, after duplicates were removed. Specific inclusion and exclusion criteria were set, and following two screening processes, 135 studies were retained for detailed abstraction and analysis. A total of 42 variables were associated with obesity in adulthood; however, of these, only seven variables may be considered as potential early markers of obesity based on the reported associations. Possible early markers of obesity included maternal smoking and maternal weight gain during pregnancy. Probable early markers of obesity included maternal body mass index, childhood growth patterns (early rapid growth and early adiposity rebound), childhood obesity and father's employment (a proxy measure for SES in many studies). Health promotion programmes/agencies should consider these factors as reasonable targets to reduce the risk of adult obesity.

Longitudinal associations of adiposity with adult lung function in the Childhood Determinants of Adult Health (CDAH) study

Childhood BMI has been reported to be positively associated with adult lung function. The aim of this study was to investigate the effect of childhood BMI on young adult lung function independently of the effects of lean body mass (LBM). Clinical and questionnaire data were collected from 654 young Australian adults (aged 27-36 years), first studied when age 9, 12, or 15 years. Adult lung function was measured by forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC ratio, and the forced expiratory flow in the middle 50% of FVC (FEF(25-75)). BMI and LBM were derived from anthropometric measures at baseline (1985) and at follow-up (2004-2006). Multivariable models were used to investigate the effect of age and sex standardized BMI in childhood on adult lung function, before and after adjustment for LBM. Adult adiposity had a strong deleterious effect on lung function, irrespective of childhood BMI, and adjustment for childhood LBM eliminated any apparent beneficial effect of childhood BMI on adult FEV(1) or FVC. This suggests that the beneficial effect of increased BMI in childhood on adult FEV(1) and FVC observed in previous longitudinal studies is likely to be attributable to greater childhood LBM not adiposity. Obese children who become obese adults can expect to have poorer lung function than those who maintain healthy weight but large deficits in lung function are also likely for healthy weight children who become obese adults. This highlights the importance of lifetime healthy weight maintenance.

Relation of early childhood growth and wheezing phenotypes to adult lung function

RATIONALE

Several studies have reported associations between indicators of birth size and postnatal growth rates with levels of pulmonary function achieved as adults. The objective of this study was to determine if levels and/or rates of weight gain, measured in early life (birth-6 years), are associated with FVC or FEV1 levels achieved in young adulthood and if these associations differ by early childhood wheezing phenotypes.

METHODS

We used data from participants in the Tucson Children's Respiratory Study (CRS), a prospective birth cohort study. Weight was measured quarterly up to age 3 years and again at age 6 years. Pulmonary function was assessed at ages 16 and 22. Mean weight and slope of weight growth between 3 and 6 years were estimated using standardized residuals. Longitudinal models were used to determine predictors of FVC and FEV1 at ages 16 and 22 years.

RESULTS

There were 127 non-Hispanic white subjects that had at least four weight measures and one or more pulmonary function measures as young adults. After adjusting for sex, height, and age, the standardized slope of weight growth (between 3 and 6 years) was positively associated with higher levels of FVC at age 16 and 22 years (P = 0.0001) among subjects who did not have preschool wheezing. However, this association was completely absent among subjects who had wheezing lower respiratory tract illnesses in the first 3 years of life. Similar trends were found for FEV1.

CONCLUSION

The rate of weight gain between 3 and 6 years is significantly positively related to adult FVC and FEV1 and this association is modified by early wheezy phenotypes.

Obesity research based on the Copenhagen School Health Records Register

INTRODUCTION

To summarise key findings from research performed using data from the Copenhagen School Health Records Register over the last 30 years with a main focus on obesity-related research. The register contains computerised anthropometric information on 372,636 schoolchildren from the capital city of Denmark. Additional information on the cohort members has been obtained via linkages with population studies and national registers.

RESEARCH TOPICS

Studies using data from the register have made important contributions in the areas of the aetiology of obesity, the development of the obesity epidemic, and the long-term health consequences of birth weight as well as body size and growth in childhood.

CONCLUSION

Research using this unique register is ongoing, and its contributions to the study of obesity as well as other topics will continue for years to come.

Lung function and overweight in school aged children after early childhood wheezing

BACKGROUND AND PURPOSE

Recently, obesity has been connected with wheezing, asthma and reduced lung function. Most previous studies have been cross-sectional. The aim of the present follow-up study was to evaluate the association of preceding or current overweight or obesity with lung function at early and late school age after early childhood wheezing.

MATERIAL AND METHODS

From the 100 children hospitalized for infection associated wheezing at <24 months of age, 83 attended the control visit at 4.0 years, 82 at 7.2 years and 81 at 12.3 years of age. Flow-volume spirometry was performed in 79 children at 7.2 years and in 80 children at 12.3 years of age. The weight status was assessed by calculating body mass index (BMI) at all visits. Age- and gender-specific BMI standard deviation scores (BMI-SDS) of >1.3 SD and >2.0 SD were defined to mean overweight and obesity, respectively.

RESULTS

Overweight at both 7.2 and 12.3 years of age was associated with decreased FEV1 /FVC (forced expiratory volume in 1 sec/forced vital capacity). Overweight and obesity at 7.2 years of age were associated with decreased FEV1 /FVC and MEF50 (maximal expiratory flow at 50% of FVC) at 12.3 years of age. The results were similar by continuous and categorized analyses, being robust to adjustments for viral findings during early childhood wheezing and asthma maintenance medication at school age.

CONCLUSION

Overweight and obesity are significant risk factors for reduced lung function at school age after early childhood wheezing. Thus, early-life wheezers should avoid excessive weight gain during childhood.

[Asthma and obesity in childhood: what is the link?]

According to the definition (body mass index>97 degrees percentile), overweight and obesity concern 15% of French children. The parallel trends in the increase in asthma and obesity may indicate a potential link between these two conditions. The purpose of this study was to review the epidemiological data indicating a relationship between asthma and obesity, to evaluate the consequences of obesity on asthma and to assess the mechanisms of this association. We conclude with the implications for treatment strategies.

Longitudinal association of body mass index with lung function: the CARDIA study

Background

Lung function at the end of life depends on its peak and subsequent decline. Because obesity is epidemic in young adulthood, we quantified age-related changes in lung function relative to body mass index (BMI).

Methods

The Coronary Artery Risk Development in Young Adults (CARDIA) study in 1985–86 (year 0) recruited 5,115 black and white men and women, aged 18–30. Spirometry testing was conducted at years 0, 2, 5 and 10. We estimated 10 year change in FVC, FEV₁ and FEV₁/FVC according to baseline BMI and change in BMI within birth cohorts with initial average ages 20, 24, and 28 years, controlling for race, sex, smoking, asthma, physical activity, and alcohol consumption.

Measurements and Main Results

Participants with baseline BMI < 21.3 kg/m² experienced 10 year increases of 71 ml in FVC and 60 ml in FEV₁ and neither measure declined through age 38. In contrast, participants with baseline BMI ≥ 26.4 kg/m² experienced 10 year decreases of 185 ml in FVC and 64 ml in FEV₁. FEV₁/FVC increased with increasing BMI. Weight gain was also associated with lung function. Those who gained the most weight over 10 years had the largest decrease in FVC, but FVC increased with weight gain in those initially thinnest. In contrast, FEV₁ decreased with increasing weight gain in all participants, with maximum decline in obese individuals who gained the most weight during the study.

Conclusion

Among healthy young adults, increasing BMI in the initially thin participants was associated with increasing then stable lung function through age 38, but there were substantial lung function losses with higher and increasing fatness. These results suggest that the obesity epidemic threatens the lung health of the general population.

[Associations between family history of allergy, exposure to tobacco smoke, active smoking, obesity, and asthma in adolescents]

OBJECTIVE

The relationships between asthma in adolescents and various environmental and social exposures needs to be clarified. The aim of this study was to determine the association between family history of allergy, passive or active tobacco smoking, obesity, and asthma in adolescents.

SUBJECTS AND METHODS

A population-based case-control study was carried out. A random sample of 4003 students aged 13 to 18 years old was selected from secondary and preparatory schools in an urban area in northeastern Mexico. Data was gathered in physical examinations and with a questionnaire administered by trained staff. Two study groups were formed: a group of 253 adolescents with asthma and a control group of students without asthma.

RESULTS

Variables associated with asthma were family history of allergy (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.28-2.06), passive smoking (OR, 1.53; 95% CI, 1.18-1.99), and obesity (OR, 1.96; 95% CI, 1.45-2.65). Female gender and active smoking were unrelated to asthma. The percentage of obese adolescents was higher in the group of asthmatics (18.2%) than in the control group (12.8%).

CONCLUSIONS

Family history of allergy, passive tobacco smoking, and obesity seem to be the main risk factors for the development of asthma in adolescents. The relationship of active smoking and asthma requires further study.