Relation of caffeine intake and blood caffeine concentrations during pregnancy to fetal growth: prospective population based study.

OBJECTIVES: To examine the association of plasma caffeine concentrations during pregnancy with fetal growth and to compare this with relations with reported caffeine intake. DESIGN: Prospective population based study. SETTING: District general hospital, inner London. SUBJECTS: Women booking for delivery between 1982 and 1984. Stored plasma was available for 1,500 women who had provided a blood sample on at least one occasion and for 640 women who had provided a sample on all three occasions (at booking, 28 weeks, and 36 weeks). MAIN OUTCOME MEASURE: Birth weight adjusted for gestational age, maternal height, parity, and sex of infant. The exposures of interest were reported caffeine consumption and blood caffeine concentration. Cigarette smoking was assessed by blood cotinine concentration. RESULTS: Caffeine intake showed no changes during pregnancy, but blood caffeine concentrations rose by 75%. Although caffeine intake increased steadily with increasing cotinine concentration above 15 ng/ml, blood caffeine concentrations fell. Caffeine consumption was inversely related to adjusted birth weight, the estimated effect being a 1.3% fall in birth weight for a 1,000 mg per week increase in intake (95% confidence interval 0.5% to 2.1%). The apparent caffeine effect was confined to cigarette smokers, among whom the estimated effect was-1.6%/1000 mg a week (-2.9% to -0.2%) after adjustment for cotinine and -1.3% (-2.7% to 0.1%) after further adjustment for social class and alcohol intake. Adjusted birth weight was unrelated to blood caffeine concentrations overall (P = 0.09, but a positive coefficient), after adjustment for cotinine (P = 0.73), or among current smokers (P = 0.45). CONCLUSIONS: Smokers consume more caffeine than non-smokers. Blood caffeine concentrations during pregnancy are not related to fetal growth, but caffeine intake is negatively associated with birth weight, with this effect being apparent only in smokers. The effect remains of borderline significance after adjustment for other factors. Prudent advice for pregnant women would be to reduce caffeine intake in conjunction with stopping smoking.     

Birth weight from pregnancies dated by ultrasonography in a multicultural British population.

OBJECTIVE--To produce standard curves of birth weight according to gestational age validated by ultrasonography in the British population, with particular reference to the effects of ethnic origin. DESIGN--Retrospective analysis of computerised obstetric database. SETTING--Three large maternity units associated with Nottingham University with over 16,000 deliveries a year. PATIENTS--41,718 women with ultrasound dated singleton pregnancies and delivery between 168 and 300 days'' gestation. MAIN OUTCOME MEASURES--Length of gestation, ethnic origin, parity, maternal height and weight at booking, smoking during pregnancy; the effect of these variables on birth weight. RESULTS--Birth weights from ultrasound dated pregnancies have a higher population mean and show less flattening of the birthweight curve at term than those of pregnancies dated from menstrual history. Significant differences were observed in mean birth weights of babies of mothers of European origin (3357 g), of Afro-Caribbean origin (3173 g), and from the Indian subcontinent (3096 g). There were also significant interethnic differences in length of gestation, parity, maternal height, booking weight, and smoking habit which affected birth weight. The ethnic differences in birth weight were even greater when the effect of smoking was excluded. CONCLUSIONS--Birthweight standards require precise dating of pregnancy and should describe the population from which they were derived. In a heterogeneous maternity population the accurate assessment of an individual baby''s weight needs to take the factors which affect birthweight standards into consideration.     

Psychosocial stress in pregnancy and its relation to low birth weight.

The relation of low birth weight to psychosocial stress in pregnancy was examined using a life events inventory and a state anxiety index. Two hundred and fifty women were randomly selected and interviewed three times during pregnancy and shortly after delivery. Twenty six were excluded. Of the remaining 224 women, nine miscarried, 195 had healthy term babies, and 20 gave birth to babies that were either premature or of low birth weight at term. Low birth weight and prematurity were significantly associated with objective major life events but not state anxiety. The occurrence of objective major life events in the third trimester may be important in precipitating preterm labour. Cigarette smoking was the best predictor and objective major life events the second best predictor of low birth weight. The result was not dependent on social class. These findings suggest that cigarette smoking may be an important mediator of stress on the fetus. Antenatal care should take greater account of stress in pregnancy, and social support systems should be evaluated.     

Social adversity,low birth weight,and preterm delivery.

A prospective study of 483 pregnant women was undertaken to examine possible associations of social and psychiatric factors with both low birth weight (less than 2500 g) and preterm delivery (less than 37 weeks'' gestation). As few babies were born before term (n = 14) or with a low birth weight (n = 14) further analyses were conducted to investigate predictors of absolute birth weight and gestational age. Low income was found to be an independent predictor of birth weight when birth weight was treated both as a dichotomous and as a continuous variable. Unemployment was found to be associated with absolute birth weight. Although this effect was statistically accounted for by low income, a low income was frequently caused by unemployment. Smoking independently predicted absolute birth weight and tended to be associated with preterm delivery. None of the factors investigated was associated with gestational age. In contrast with previous findings, factors such as social class, adverse life events, and psychiatric state were not associated with birth outcome. The mechanism underlying the association between low income and low birth weight requires further investigation.     

Associations between periconceptional alcohol consumption and craniosynostosis, omphalocele, and gastroschisis

BACKGROUND: Alcohol consumption during pregnancy is known to be associated with certain birth defects, but the risk of other birth defects is less certain. The authors examined associations between maternal alcohol consumption during pregnancy and craniosynostosis, omphalocele, and gastroschisis among participants in the National Birth Defects Prevention Study, a large, multicenter case–control study. METHODS: A total of 6622 control infants and 1768 infants with birth defects delivered from 1997–2005 were included in the present analysis. Maternal alcohol consumption was assessed as any periconceptional consumption (1 month prepregnancy through the third pregnancy month), and by quantity‐frequency, duration, and beverage type. Alcohol consumption throughout pregnancy was explored for craniosynostosis since the period of development may extend beyond the first trimester. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression analysis. OR were adjusted for age, race/ethnicity, and state of residence at time of infant's birth. Gastroschisis OR were also adjusted for periconceptional smoking. RESULTS: Periconceptional alcohol consumption and craniosynostosis showed little evidence of an association (OR = 0.92; CI: 0.78–1.08), but alcohol consumption in the second (OR = 0.65; CI: 0.47–0.92) and third trimesters (OR = 0.68; CI: 0.49–0.95) was inversely associated with craniosynostosis. Periconceptional alcohol consumption was associated with omphalocele (OR = 1.50; CI: 1.15–1.96) and gastroschisis (OR = 1.40; CI: 1.17–1.67). CONCLUSIONS: Results suggest that maternal periconceptional alcohol consumption is associated with omphalocele and gastroschisis, and second and third trimester alcohol consumption are inversely associated with craniosynostosis. Birth Defects Research (Part A) 2011. © 2011 Wiley‐Liss, Inc.     

Maternal fatness and viability of preterm infants

To investigate the effect of maternal fatness on the mortality of infants born preterm up to the corrected age of 18 months 795 mother-infant pairs were studied. Maternal fatness was defined by Quetelet''s index (weight/(height²)) and all infants weighed less than 1850 g at birth. In 771 mother-infant pairs maternal age, complications of pregnancy, mode of delivery, parity, social class, and the baby''s sex and gestation were analysed by a logistic regression model for associations with infant mortality (but deaths from severe congenital abnormalities and those occurring during the first 48 hours after birth were excluded). In a subgroup of 284 mother-infant pairs all infant deaths except those from severe congenital abnormalities were analysed in association with the infant''s birth weight and gestation and the mother''s height and weight; this second analysis included another 24 infants who had died within 48 hours after birth. In the first analysis mortality overall was 7% (55/771), rising from 4% (71/173) in thin mothers (Quetelet''s index <20) to 15% (6/40) in mothers with grades II and III obesity (Quetelet''s index >30). After adjusting for major demographic and antenatal factors, including serious complications of pregnancy, maternal fatness was second in importance only to length of gestation in predicting death of infants born preterm. In the second analysis mortality overall was 15% (44/284), rising from 9% (5/53) in thin mothers to 47% (8/17) in mothers with grades II and III obesity. In both analyses the relative risk of death by 18 months post-term was nearly four times greater in infants born to obese mothers than in those born to thin mothers. In addition, maternal fatness was associated with reduced birth weight, whereas it is associated with macrosomia in term infants.These data differ fundamentally from those reported in full term babies of obese mothers. It is speculated that the altered metabolic milieu in obesity may reduce the ability of the fetus to adapt to extrauterine life if it is born preterm.     

Effects of grandmothers' smoking in pregnancy on birth weight: intergenerational cohort study

Objective To investigate the influences on birth weight of maternal smoking during pregnancy across generations.Design Intergenerational cohort study.Participants Members of the 1958 birth cohort and their offspring and mothers.Setting England, Scotland, and Wales.Main outcome measure Birth weight.Results Information on grandmothers'' smoking during pregnancy was available for 9028 singleton offspring of 4302 female cohort members. Assuming heritable transmission through the intergenerational association, grandmothers'' smoking was predicted to result in a 34 g reduction (95% confidence interval -41 g to -28 g) in the birth weight of grandchildren. Random effects models showed a negative association between grandmothers'' smoking and birth weight of grandchildren (β regression coefficient -24 g, -50 g to 3 g), but this effect was eliminated after adjustment for maternal smoking (0 g, -26 g to 26 g).No association was evident among the offspring of non-smoking mothers (n = 6105; 14 g, -17 g to 46 g), and after adjustment for maternal birth weight, adult height and body mass index, grandmothers'' smoking was positively associated with the birth weight of grandchildren (45 g, 10 g to 80 g).Conclusion Deficits in mothers'' birth weight attributable to their mother smoking was not evident in the grandchildren.     

Familial Trends in Low Birth Weight

The reproductive performance of sisters and sisters-in-law of 185 women who had delivered “light-for-dates” and “premature expulsion” low birth weight infants was studied. Percentile birth weights were compared taking into account length of gestation, fetal sex, and the height, weight, parity, and smoking habits of the mother. Sisters of women who had delivered light-for-dates babies had lighter babies than the general population, their sisters-in-law, or the sisters of women in the premature expulsion group. These other groups, however, had the expected distribution of percentile birth weights. Data on familial trends in smoking habits and unknown gestation are also presented. The results are consistent with the theory that the mother''s own intrauterine experience affects her reproductive performance but could also be explained by shared family learning experience of as yet unidentified microsocial factors related to pregnancy performance.     

Adolescent Self-Organization and Adult Smoking and Drinking over Fifty Years of Follow-Up: The British 1946 Birth Cohort

Variations in markers of adolescent self-organization predict a range of economic and health-related outcomes in general population studies. Using a population-based birth cohort study we investigated associations between adolescent self-organization and two common factors over adulthood influencing health, smoking and alcohol consumption. The MRC National Survey of Health and Development (the British 1946 birth cohort) was used to test associations between a dimensional measure of adolescent self-organization derived from teacher ratings, and summary longitudinal measures of smoking and alcohol consumption over the ensuing five decades. Multinomial regression models were adjusted for sex, adolescent emotional and conduct problems, occupational social class of origin, childhood cognition, educational attainment and adult occupational social class. With all covariates adjusted, higher adolescent self-organization was associated with fewer smoking pack years, although not with quitting; there was no association with alcohol consumption across adulthood (none or heavy compared with light to moderate). Adolescent self-organization appears to be protective against smoking, but not against heavy alcohol consumption. Interpretation of this differential effect should be embedded in an understanding of the social and sociodemographic context in which these health behaviours occur over time.     

The relationship between psychosocial stress, age, BMI, CRP, lifestyle, and the metabolic syndrome in apparently healthy subjects

The aim of this cross-sectional study was to examine the factors which may be associated with the metabolic syndrome by exploring the relationship between psychosocial stress, age, body mass index (BMI), C-reactive protein (CRP), lifestyle factors, and the components of the metabolic syndrome, such as glycated hemoglobin (HbA1c), fasting blood sugar (FBS), body fat percentage, and triglyceride concentration, among apparently healthy subjects. Psychosocial stress was measured by the use of the inventory to measure psychosocial stress (IMPS). One thousand four hundred and ninety-nine people out of 1,941 public school workers admitted to a hospital for a medical check-up responded to the IMPS, yielding a response rate of 77.2%. A total of 1,201 workers excluding 298 who were taking medication for various diseases were analyzed with the use of hierarchical multiple regression models. It was found that IMPS-measured stress score, age, BMI, and smoking habit were associated with an increase in glycated hemoglobin among men, while alcohol consumption was associated with a decrease in glycated hemoglobin. Stress score, age, BMI, and alcohol consumption were found to be associated with an increase in FBS among men, while smoking and exercise habits were associated with a decrease in FBS. CRP was found to be associated with an increase in body fat percentage among men, though stress score was not associated with an increase in body fat percentage. Stress score, age, and BMI were associated with an increase in triglyceride concentration among women. The findings of the present study seem to be in line with the hypothesis that psychosocial stress plays an important role in developing the metabolic syndrome, which may be associated with inflammatory processes in the vascular wall, resulting in atherosclerosis and cardiovascular disease.     

Effect of Prenatal Alcohol Exposure on Childhood Academic Outcomes: Contrasting Maternal and Paternal Associations in the ALSPAC Study

Background

The impact of low-to-moderate levels of alcohol consumption during pregnancy on child cognitive outcomes has been of recent concern. This study has tested the hypothesis that low-to-moderate maternal alcohol use in pregnancy is associated with lower school test scores at age 11 in the offspring via intrauterine mechanisms.

Methods

We used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a birth cohort study based in the South West of England. Analyses were conducted on 7062 participants who had complete data on: maternal and paternal patterns of alcohol use in the first trimester and at 18 weeks'' gestation, child''s academic outcomes measured at age 11, gender, maternal age, parity, marital status, ethnicity, household crowding, home ownership status and parental education. We contrasted the association of mother''s alcohol consumption during pregnancy with child''s National Curriculum Key Stage 2 (KS2) test scores with the association for father''s alcohol consumption (during the time the mother was pregnant) with child''s National Curriculum Key Stage 2 (KS2) test scores. We used multivariate linear regression to estimate mean differences and 95% confidence intervals [CI] in KS2 scores across the exposure categories and computed f statistics to compare maternal and paternal associations.

Findings and conclusions

Drinking up to 1 unit of alcohol a day during pregnancy was not associated with lower test scores. However, frequent prenatal consumption of 4 units (equivalent to 32 grams of alcohol) on each single drinking occasion was associated with reduced educational attainment [Mean change in offspring KS2 score was −0.68 (−1.03, −0.33) for maternal alcohol categories compared to 0.27 (0.07, 0.46) for paternal alcohol categories]. Frequent consumption of 4 units of alcohol during pregnancy may adversely affect childhood academic outcomes via intrauterine mechanisms.     

Association of paternal alcohol use with gestational age and birth weight.

Paternal alcohol use has been associated with a number of adverse reproductive outcomes in laboratory animals and there is one epidemiologic report of a detrimental effect on infant birth weight. To expand the epidemiologic evidence, data from the Child Health and Development Studies were analyzed. Data collected from the onset of prenatal care in 10,232 women enrolled in the Kaiser Foundation Health Plan and residing in the San Francisco East Bay area between June 1959 and September 1966 were available, including information on the mother's report of paternal alcohol consumption and a number of potential confounders. Pregnancy outcomes included preterm delivery (< 37 weeks completed gestation), moderately low birth weight (1,501-2,500 g), very low birth weight (< or = 1,500 g), small-for-gestational-age (< 10th percentile of weight for gestational age), and mean birth weight. Paternal alcohol use, analyzed in intervals from 0 to 2.0 or more drinks per day, showed no association with any of the outcomes of interest. Adjusted prevalence odds ratios ranged from 0.7 to 1.5, with no indication of a monotonic dose-response gradient. Mean birth weight was also virtually unrelated to paternal alcohol use. Compared with the earlier report, this population had a very modest level of alcohol consumption. Nonetheless, within the range that was studied there appears to be no association between paternal alcohol use and birth outcome.     

Sleep Quality during Exam Stress: The Role of Alcohol,Caffeine and Nicotine

Academic exam stress is known to compromise sleep quality and alter drug consumption in university students. Here we evaluated if sleeping problems and changes in legal drug consumption during exam stress are interrelated. We used the Pittsburgh Sleep Quality Index (PSQI) to survey sleep quality before, during, and after an academic exam period in 150 university students in a longitudinal questionnaire study. Self-reports of alcohol, caffeine, and nicotine consumption were obtained. The Perceived Stress Questionnaire (PSQ-20) was used as a measure of stress. Sleep quality and alcohol consumption significantly decreased, while perceived stress and caffeine consumption significantly increased during the exam period. No significant change in nicotine consumption was observed. In particular, students shortened their time in bed and showed symptoms of insomnia. Mixed model analysis indicated that sex, age, health status, as well as the amounts of alcohol and caffeine consumed had no significant influence on global sleep quality. The amount of nicotine consumed and perceived stress were identified as significant predictors of diminished sleep quality. Nicotine consumption had a small-to-very-small effect on sleep quality; perceived stress had a small-to-moderate effect. In conclusion, diminished sleep quality during exam periods was mainly predicted by perceived stress, while legal drug consumption played a minor role. Exam periods may pose an interesting model for the study of stress-induced sleeping problems and their mechanisms.     

Variation in size at birth and cigarette smoking during pregnancy

The influence of cigarette smoking during pregnancy and other familial factors on size at birth and gestation length is investigated among 458 births to 227 mothers living in a suburban community in the U.S. In this sample, 56% of the births were to mothers who reported not smoking during the pregnancy and 35% were to mothers who reported smoking 20 cigarettes or less. Multiple stepwise regression analysis was employed to examine the influence of cigarette smoking after statistical adjustment for such social and biological characteristics of the family as parents' sizes, education, income, and aspects of mother's reproductive history. After correction for significant social and biological characteristics, smoking status was a significant contributor to birth weight variation. In fact, cigarette smoking had the next-largest partial correlation coefficient (r = -0.26) second to gestation length. Birth length is also negatively associated with cigarette smoking, though not so strongly as is birth weight. The reduction in birth lengths can be attributed to the reduction in birth weights. Gestation length was not associated with cigarette smoking in this sample. The analysis of collinearity between smoking status and the other independent variables indicates that the effect of smoking appears to be independent of interrelationships among the independent variables.     

Mental health,job satisfaction,and job stress among general practitioners.

OBJECTIVE--To identify sources of job stress associated with high levels of job dissatisfaction and negative mental wellbeing among general practitioners in England. DESIGN--Multivariate analysis of large database of general practitioners compiled from results of confidential questionnaire survey. Data obtained on independent variables of job stress, demographic factors, and personality. Dependent variables were mental health, job satisfaction, alcohol consumption, and smoking. SETTING--National sample of general practitioners studied by university department of organisational psychology. SUBJECTS--One thousand eight hundred seventeen general practitioners selected at random by 20 family practitioner committees in England. INTERVENTIONS--None. END POINT--Determination of the combination of independent variables that were predictive of mental health and job satisfaction. MEASUREMENTS AND MAIN RESULTS--Women general practitioners both had job satisfaction and showed positive signs of mental wellbeing in contrast with other normative groups. Conversely, male doctors showed significantly higher anxiety scores than the norms, had less job satisfaction, and drank more alcohol than their women counterparts. Multivariate analysis disclosed four job stressors that were predictive of high levels of job dissatisfaction and lack of mental wellbeing; these were demands of the job and patients'' expectations, interference with family life, constant interruptions at work and home, and practice administration. CONCLUSIONS--There may be substantial benefit in providing a counselling service for general practitioners and other health care workers who suffer psychological pressure from their work.     

Quantifying the impact of deprivation on preterm births: a retrospective cohort study

Background

Social deprivation is associated with higher rates of preterm birth and subsequent infant mortality. Our objective was to identify risk factors for preterm birth in the UK''s largest maternity unit, with a particular focus on social deprivation, and related factors.

Methodology/Principal Findings

Retrospective cohort study of 39,873 women in Liverpool, UK, from 2002–2008. Singleton pregnancies were stratified into uncomplicated low risk pregnancies and a high risk group complicated by medical problems. Multiple logistic regression, and generalized additive models were used to explore the effect of covariates including area deprivation, smoking status, BMI, parity and ethnicity on the risk of preterm birth (34⁺⁰ weeks). In the low risk group, preterm birth rates increased with deprivation, reaching 1.6% (CI₉₅ 1.4 to 1.8) in the most deprived quintile; the unadjusted odds ratio comparing an individual in the most deprived quintile, to one in the least deprived quintile was 1.5 (CI₉₅ 1.2 to 1.9). Being underweight and smoking were both independently associated with preterm birth in the low risk group, and adjusting for these factors explained the association between deprivation and preterm birth. Preterm birth was five times more likely in the high risk group (RR 4.8 CI₉₅ 4.3 to 5.4), and there was no significant relationship with deprivation.

Conclusions

Deprivation has significant impact on preterm birth rates in low risk women. The relationship between low socio-economic status and preterm births appears to be related to low maternal weight and smoking in more deprived groups.     

Lifecourse Social Position and D-Dimer; Findings from the 1958 British Birth Cohort

The aim is to examine the association of lifecourse socioeconomic position (SEP) on circulating levels of D-dimer. Data from the 1958 British birth cohort were used, social class was determined at three stages of respondents'' life: at birth, at 23 and at 42 years. A cumulative indicator score of SEP (CIS) was calculated ranging from 0 (always in the highest social class) to 9 (always in the lowest social class). In men and women, associations were observed between CIS and D-dimer (P<0.05). Thus, the respondents in more disadvantaged social classes had elevated levels of D-dimer compared to respondents in less disadvantaged social class. In multivariate analyses, the association of disadvantaged social position with D-dimer was largely explained by fibrinogen, C-reactive protein and von Willebrand Factor in women, and additionally by smoking, alcohol consumption and physical activity in men. Socioeconomic circumstances across the lifecourse at various stages also contribute independently to raised levels of D-dimer in middle age in women only. Risk exposure related to SEP accumulates across life and contributes to raised levels of D-dimer. The association of haemostatic markers and social differences in health may be mediated by inflammatory and other markers.     

Risk factors for perinatal mortality in Canada

A population-based computer record-linkage study of infant births and deaths in 1978 and 1979 in eight Canadian provinces (Quebec and Newfoundland were excluded) was undertaken to permit analysis of perinatal mortality in relation to maternal and infant characteristics. Perinatal mortality rates were significantly higher in nonurban than in urban areas (p < 0.05). A logistic regression model was used to assess the effects on perinatal mortality of variables reported on birth and stillbirth records. This model included length of gestation, infant''s birth weight and sex, number of previous births and number of previous stillbirths as well as an interaction term for length of gestation and birth weight. For early-neonatal mortality, odds ratios over 8 were observed for birth weight less than 2500 g or gestation less than 35 weeks. About 75% of early-neonatal mortality was attributable to low birth weight or fetal immaturity. Greater emphasis should be placed on the prevention of low birth weight.     

Size at birth,maternal nutritional status in pregnancy,and blood pressure at age 17: population based analysis.

OBJECTIVE: To assess the effect of size at birth, maternal nutrition, and body mass index on blood pressure in late adolescence. DESIGN: Population based analysis of birth weight corrected for gestational age, mother''s weight before pregnancy and weight gain in pregnancy, obtained from the Jerusalem perinatal study, and blood pressure and body mass index at age 17, available from military draft records. SETTING: Jerusalem, Israel. SUBJECTS: 10,883 subjects (6684 men and 4199 women) born in Jerusalem during 1974-6 and subsequently drafted to the army. MAIN OUTCOME MEASURES: Systolic and diastolic blood pressures measured at age 17 and their correlation with birth weight, size at birth, mother''s body mass index and weight gain during pregnancy, and height and weight at age 17. RESULTS: Systolic and diastolic blood pressures were significantly and positively correlated with body weight, height, body mass index at age 17, and with mother''s body weight and body mass index before pregnancy, but not with birth weight or mother''s weight gain in pregnancy. CONCLUSION: Variables reflecting poor intrauterine nutrition, including low maternal body mass index before pregnancy, poor maternal weight gain in pregnancy, and being born small for gestational age, were not associated with a higher blood pressure in late adolescence.     

Outdoor artificial light at night,obesity, and sleep health: Cross-sectional analysis in the KoGES study

Obesity is a common disorder with many complications. Although chronodisruption plays a role in obesity, few epidemiological studies have investigated the association between artificial light at night (ALAN) and obesity. Since sleep health is related to both obesity and ALAN, we investigated the association between outdoor ALAN and obesity after adjusting for sleep health. We also investigated the association between outdoor ALAN and sleep health. This cross-sectional survey included 8526 adults, 39–70 years of age, who participated in the Korean Genome and Epidemiology Study. Outdoor ALAN data were obtained from satellite images provided by the US Defense Meteorological Satellite Program. We obtained individual data regarding outdoor ALAN; body mass index; depression; and sleep health including sleep duration, mid-sleep time, and insomnia; and other demographic data including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking status and consumption of caffeine or alcohol before sleep. A logistic regression model was used to investigate the association between outdoor ALAN and obesity. The prevalence of obesity differed significantly according to sex (women 47% versus men 39%, p < 0.001) and outdoor ALAN (high 55% versus low 40%, p < 0.001). Univariate logistic regression analysis revealed a significant association between high outdoor ALAN and obesity (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.14–1.35, p < 0.001). Furthermore, multivariate logistic regression analyses showed that high outdoor ALAN was significantly associated with obesity after adjusting for age and sex (OR 1.25, 95% CI 1.14–1.37, p < 0.001) and even after controlling for various other confounding factors including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking, consumption of caffeine or alcohol before sleep, delayed sleep pattern, short sleep duration and habitual snoring (OR 1.20, 95% CI 1.06–1.36, p = 0.003). The findings of our study provide epidemiological evidence that outdoor ALAN is significantly related to obesity.