Effects of interpregnancy intervals on preterm birth,intrauterine growth retardation,and fetal loss

Abstract

This study examines the magnitude and shape of the interpregnancy interval (IPI) effect on three pregnancy outcomes: preterm low birthweight (PRETERM‐LBW), intrauterine growth‐retardation low birthweight (IUGR‐LBW), and fetal loss (LOSS). A multinomial logistic regression model is estimated, based on data from the 1988 National Survey of Family Growth which contains pregnancy histories. The results indicate that both short and long intervals raise the risk of IUGR‐LBW and LOSS, net of sociodemographic and behavioral variables, but IPI effects on PRETERM‐LBW are not clear.     

Independent and Joint Effects of Prenatal Zinc and Vitamin A Deficiencies on Birthweight in Rural Sidama,Southern Ethiopia: Prospective Cohort Study

Background

The effects of prenatal Zinc Deficiency (ZD) and Vitamin A Deficiency (VAD) on birthweight are controversial and their interaction has not been investigated.

Objective

To assess the independent and interaction effects of prenatal zinc and vitamin A deficiencies on birthweight in rural Sidama, Southern Ethiopia.

Methodology

A community-based prospective cohort study design was employed. Six hundred fifty pregnant women in their second or third trimester were randomly selected and their serum zinc and retinol concentrations were determined. About 575 subjects were successfully followed until delivery and birthweight was measured within 72 hours after delivery. The association between the exposures and birthweight was examined using log-binomial and liner regression analyses. Potential interaction between ZD and VAD was examined using Synergy Index (SI).

Results

The mean birthweight (± standard deviation) was 2896 g (±423). About 16.5% (95% CI: 13.5–19.6%) of the babies had Low Birthweight (LBW). Prenatal ZD and VAD were not significantly associated to LBW with Adjusted Relative Risk (ARR) of 1.25 (95 CI: 0.86–1.82) and 1.27 (95% CI: 0.86–1.87), respectively. Stratified analysis on the basis of gestational trimester showed that the occurrence of the deficiencies neither in the second nor third trimester were associated to LBW. The deficiencies did not show synergetic interaction in causing LBW [SI = 1.04 (95% CI: 0.17–6.28)]. Important risk factors of LBW were maternal illiteracy [RR = 1.80 (95% CI: 1.11–2.93)], female sex of the newborn [RR = 1.79 (95% CI: 1.19–2.67)], primiparity [RR = 1.16 (95% CI: 1.02–1.35)], short maternal stature [RR = 1.63 (95% CI: 1.06–2.51)] and maternal thinness [RR = 1.52 (95% CI: 1.03–2.25)]. In the linear regression model, elevated CRP was also negatively associated to birthweight.

Conclusion

LBW is of public health significance in the locality. The study did not witness any independent or interaction effect of prenatal ZD and VAD on birthweight.     

Academic and psychosocial characteristics of low‐birthweight adolescents

Abstract

A sample of 94 children with low birthweights (LBW ≤ 2500 grams) was identified in a group of 857 children who took part in an 18‐year follow‐up study of the Danish Prospective Perinatal Cohort. The LBW group was compared with the rest of the sample on a set of long‐term intellectual and psychosocial outcomes. In addition, the relative predictive power of low birthweight and a set of environmental variables regressed on two adolescent academic outcomes was examined. No significant residual or complicating effects of LBW were found on any outcomes after 18 years. However, full‐birthweight adolescents possessed diferential characteristics with respect to the pattern of correlated environmental variables. LBW adolescents appear to have a greater sensitivity to environmental influences. For males, stability of adult figures and general order and structure are more conducive to an optimal outcome; for females, the strongest predictor was level of maternal psychological adaptation or general contentment.     

The effect of birthweight on tooth-size variability in twins.

Studies indicate that low birthweight (LBW) children display reduced deciduous tooth size but there is little information about permanent tooth size. It has also been shown that dental fluctuating asymmetry (FA) increases in response to various environmental influences, but the relationship between birthweight and FA remains unclear. The aim of this study was to compare tooth size and asymmetry, according to birthweight, in the deciduous and permanent dentitions of a sample of Australian twins. The study sample comprised 436 twins, classified into 2 groups: normal birthweight (NBW > 2500 g) and low birthweight (LBW < or = 2500 g). For each individual it was generally possible to measure maximum mesiodistal crown diameters of both deciduous and permanent central incisors from serial dental models. Correlations were calculated between tooth-size variables and birthweight; subsequently comparisons of tooth size and FA were made between the LBW and NBW samples using Student's t tests. Small positive correlations (around .1) were noted between birthweight and tooth-size variables. There was no evidence of tooth-size reduction in the LBW male sample, but the LBW females displayed tooth-size reduction of approximately 2-3% for both deciduous and permanent incisors, compared to the NBW females. There was no evidence of increased FA in the LBW individuals of either sex. These findings indicate that developing teeth are generally well-protected from developmental disturbances during prenatal and perinatal periods. Further research is needed to clarify the biological basis of an apparently true but weak association between tooth size and birthweight.     

Birthweight and risk of thyroid cancer and its histological types: A large cohort study

BackgroundThe aetiology of thyroid cancer is poorly understood, but it is possible that this malignancy has origins early in life. It is, however, currently unknown if birthweight, as an indicator of prenatal growth, is related to thyroid cancer risk.ObjectiveTo investigate if birthweight is associated with the later risk of thyroid cancer and its histological types.Methods246,141 children (120,505 girls, 125,636 boys) from the Copenhagen School Health Records Register, born 1936–1989, were prospectively followed in the Danish Cancer Registry. Cox regressions were used to estimate hazards ratios (HR) and 95% confidence intervals (CI).ResultsDuring follow up, 241 individuals (172 women, 69 men) were diagnosed with thyroid cancer (162 papillary, 53 follicular). Birthweight was significantly and positively associated with risk of thyroid cancer overall (HR = 1.30 [95% CI: 1.03–1.64] per kilogram). There were no sex differences in the associations. Birthweight was positively and significantly associated with follicular thyroid cancer (HR = 1.74 [95% CI: 1.07–2.82] per kilogram), and although there was an indication of a positive association, it did not reach statistical significance for the more common papillary type (HR = 1.20 [95% CI: 0.90–1.59] per kilogram).ConclusionA heavier weight at birth is associated with an elevated risk of total and follicular thyroid cancer, which underscores that prenatal exposures may be important in thyroid cancer aetiology.     

Birth weight,adult body size,and risk of colorectal cancer

BackgroundEvidence suggests that birth weight may be associated with colorectal cancer (CRC) risk later in life. Whether the association is mediated by adult body size remains unexamined.MethodCox proportional hazards models (Hazard Ratio (HR) and 95 % Confidence Intervals (CI)) were used to evaluate the association between self-reported birth weight (<6 lbs, 6-<8 lbs, ≥8 lbs) and CRC risk among 70,397 postmenopausal women from the Women’s Health Initiative. Further, we assessed whether this association was mediated by adult body size using multiple mediation analyses.ResultsCompared with birth weights of 6-< 8 lbs, birth weight ≥ 8 lbs was associated with higher CRC risk in postmenopausal women (HR = 1.31, 95 % CI 1.16–1.48). This association was significantly mediated by adult height (proportion mediated =11.4 %), weight (11.2 %), waist circumference (10.9 %), and body mass index at baseline (4.0 %). The joint effect of adult height and weight explained 21.6 % of this positive association.ConclusionOur data support the hypothesis that the intrauterine environment and fetal development may be related to the risk of developing CRC later in life. While adult body size partially explains this association, further investigation is required to identify other factors that mediate the link between birth weight and CRC.     

Effects of Maternal Pregnancy Intention,Depressive Symptoms and Social Support on Risk of Low Birth Weight: A Prospective Study from Southwestern Ethiopia

Background

Low birth weight (LBW) is the principal risk factor for neonatal and infant mortality in developing countries. This study examines the effects of unwanted pregnancy, prenatal depression and social support on the risk of low birth weight in rural southwestern Ethiopia. We hypothesized that unwanted pregnancy and prenatal depression increase the risk of low birth weight, while social support mediates this association.

Methods

Data for the study comes from a prospective study in which women were followed from pregnancy through to delivery. Six hundred twenty two women were followed and 537 birth weights were measured within 72 hours. Multivariable log binomial regression was used to model the risk of low birth weight.

Results

The mean birth weight was 2989 grams (SD±504 grams), and the incidence of LBW was 17.88%. The mean birth weight of babies after unwanted pregnancy was 114 g lower compared to births from intended pregnancy. Similarly, mean birth weight for babies among women with symptoms of antenatal depression was 116 grams lower. Results of unadjusted log-binomial regression showed that unwanted pregnancy, prenatal depression and social support were associated with LBW. The relationship between antenatal depressive symptoms and LBW was mediated by the presence of social support, while the association between LBW and unwanted pregnancy remained after multivariable adjustment.

Conclusion

The incidence of low birth weight is high in the study area. Poverty, nonuse of antenatal care, low social support and unwanted pregnancy contribute to this high incidence of low birth weight. Hence, identifying women’s pregnancy intention during antenatal care visits, and providing appropriate counseling and social support will help improve birth outcomes.     

Birthweight‐specific infant mortality risks for native Americans and whites,United States, 1960 and 1984

Abstract

We used NCHS natality and linked‐birth/death certificate tapes to compare birthweight‐specific neonatal and postneonatal mortality risks for Native Americans and whites in 1960 and in 1984. The birthweight distributions for the two groups were similar both years. Native American neonatal mortality risk dropped from 20.2 in 1960 to 5.2 in 1984, and the relative risk for Native Americans with respect to whites fell from 1.31 in 1960 to a nonsignificant difference in 1984. Postneonatal mortality risks for Native Americans fell from 27.5 in 1960 to 6.2 in 1984, with a drop in the relative risk from 5.2 to 2.1. Although the relative improvements for Native Americans were highest in postneonatal survival, Native Americans still had over twice the level of white postneonatal mortality. Birthweight was positively associated with survival for both groups, but the odds of Native American neonatal death were affected less by low and very low birthweights. For both groups, improvements in neonatal mortality were highest at the lower birthweights, while the gains in postneonatal survival benefitted normal and high birthweight infants most.     

Depression in pregnancy,infant birth weight and DNA methylation of imprint regulatory elements

Depressed mood in pregnancy has been linked to low birth weight (LBW, < 2,500 g), a risk factor for adult-onset chronic diseases in offspring. We examined maternal depressed mood in relation to birth weight and evaluated the role of DNA methylation at regulatory sequences of imprinted genes in this association. We measured depressed mood among 922 pregnant women using the CES-D scale and obtained birth weight data from hospital records. Using bisulfite pyrosequencing of cord blood DNA from 508 infants, we measured methylation at differentially methylated regions (DMRs) regulating imprinted genes IGF2/H19, DLK1/MEG3, MEST, PEG3, PEG10/SGCE, NNAT and PLAGL1. Multiple regression models were used to examine the relationship between depressed mood, birth weight and DMR methylation levels. Depressed mood was associated with a more that 3-fold higher risk of LBW, after adjusting for delivery mode, parity, education, cigarette smoking, folic acid use and preterm birth. The association may be more pronounced in offspring of black women and female infants. Compared with infants of women without depressed mood, infants born to women with severe depressed mood had a 2.4% higher methylation at the MEG3 DMR. Whereas LBW infants had 1.6% lower methylation at the IGF2 DMR, high birth weight (> 4,500 g) infants had 5.9% higher methylation at the PLAGL1 DMR compared with normal birth weight infants. Our findings confirm that severe maternal depressed mood in pregnancy is associated with LBW, and that MEG3 and IGF2 plasticity may play important roles.     

Depression in pregnancy,infant birth weight and DNA methylation of imprint regulatory elements

Depressed mood in pregnancy has been linked to low birth weight (LBW, < 2,500 g), a risk factor for adult-onset chronic diseases in offspring. We examined maternal depressed mood in relation to birth weight and evaluated the role of DNA methylation at regulatory sequences of imprinted genes in this association. We measured depressed mood among 922 pregnant women using the CES-D scale and obtained birth weight data from hospital records. Using bisulfite pyrosequencing of cord blood DNA from 508 infants, we measured methylation at differentially methylated regions (DMRs) regulating imprinted genes IGF2/H19, DLK1/MEG3, MEST, PEG3, PEG10/SGCE, NNAT and PLAGL1. Multiple regression models were used to examine the relationship between depressed mood, birth weight and DMR methylation levels. Depressed mood was associated with a more that 3-fold higher risk of LBW, after adjusting for delivery mode, parity, education, cigarette smoking, folic acid use and preterm birth. The association may be more pronounced in offspring of black women and female infants. Compared with infants of women without depressed mood, infants born to women with severe depressed mood had a 2.4% higher methylation at the MEG3 DMR. Whereas LBW infants had 1.6% lower methylation at the IGF2 DMR, high birth weight (> 4,500 g) infants had 5.9% higher methylation at the PLAGL1 DMR compared with normal birth weight infants. Our findings confirm that severe maternal depressed mood in pregnancy is associated with LBW, and that MEG3 and IGF2 plasticity may play important roles.     

Low Birthweight (LBW) and Neonatal Hyperbilirubinemia (NNH) in an Indian Cohort: Association of Homocysteine,Its Metabolic Pathway Genes and Micronutrients as Risk Factors

Background & Aims

Indian subcontinent has the highest child mortality rates along with a very high frequency of low birthweight (LBW). Folate and vitamin B12 (Vit-B12) are necessary during foetal development and their deficiency prevalence in Indians is very high. The objective of the present paper is to assess whether foetal homocysteine (Hcy)/folate metabolic pathway genes, their cofactors and homocysteine level independently (or collectively) predispose children to Low birth weight.

Methods

Cord blood was collected for the study. Frequency of 5 SNPs in 4-Hcy-pathway genes, and levels of Hcy, Vit-B12 and folate were evaluated.

Results

Of the 421 newborns recruited for the study, 38% showed low birth weight (<2.5kg) and 16% were preterm babies. 101 neonates developed neonatal hyperbilirubinemia (NNH). High prevalence of Vit-B12 (65%) and folate (27%) deficiency was observed in newborns along with hyperhomocystinemia (hypHcy-25%). Preterm delivery, micronutrient deficiency, hypHcy and MTHFR 677T SNP are associated as risk factor while G allele of TCN2 C776G is protective against LBW. MTHFR 677T allele and folate deficiency are also independent risk factors for NNH.

Conclusion

We record the highest incidence of Vit-B12, folate deficiency and elevated Hcy levels, of all the studies so far reported on neonates. These together with MTHFR 677T are potential risk factors for LBW. Association of impaired folate/Hcy metabolism with NNH is reported for the first time and the possible way of interaction is discussed. It appears that proper nutritional management during pregnancy would reduce the risk of complex clinical outcomes.     

Ecological study of social fragmentation,poverty, and suicide

ObjectivesTo investigate the association between suicide and area based measures of deprivation and social fragmentation.DesignEcological study.Setting633 parliamentary constituencies of Great Britain as defined in 1991.ResultsMortality from suicide and all other causes increased with increasing Townsend deprivation score, social fragmentation score, and abstention from voting in all age and sex groups. Suicide mortality was most strongly related to social fragmentation, whereas deaths from other causes were more closely associated with Townsend score. Constituencies with absolute increases in social fragmentation and Townsend scores between 1981 and 1991 tended to have greater increases in suicide rates over the same period. The relation between change in social fragmentation and suicide was largely independent of Townsend score, whereas the association with Townsend score was generally reduced after adjustment for social fragmentation.ConclusionsSuicide rates are more strongly associated with measures of social fragmentation than with poverty at a constituency level.

Key messages

• Place of residence may affect health, and mortality from most common diseases tends to be higher in areas characterised by low socioeconomic position
• Research dating back over 100 years suggests that social fragmentation may influencesuicide
• In the 1980s and 1990s, parliamentary constituencies with high levels of social fragmentation had high rates of suicide, independent of deprivation
• Constituencies with the greatest increases in social fragmentation between 1981 and 1991 also had the greatest increases in suicide rates over the same period
• Any targeting of suicide prevention may be more effective if aimed at socially fragmented rather than deprived areas

     

Biomarkers of dairy fat intake,incident cardiovascular disease,and all-cause mortality: A cohort study,systematic review,and meta-analysis

BackgroundWe aimed to investigate the association of serum pentadecanoic acid (15:0), a biomarker of dairy fat intake, with incident cardiovascular disease (CVD) and all-cause mortality in a Swedish cohort study. We also systematically reviewed studies of the association of dairy fat biomarkers (circulating or adipose tissue levels of 15:0, heptadecanoic acid [17:0], and trans-palmitoleic acid [t16:1n-7]) with CVD outcomes or all-cause mortality.Methods and findingsWe measured 15:0 in serum cholesterol esters at baseline in 4,150 Swedish adults (51% female, median age 60.5 years). During a median follow-up of 16.6 years, 578 incident CVD events and 676 deaths were identified using Swedish registers. In multivariable-adjusted models, higher 15:0 was associated with lower incident CVD risk in a linear dose–response manner (hazard ratio 0.75 per interquintile range; 95% confidence interval 0.61, 0.93, P = 0.009) and nonlinearly with all-cause mortality (P for nonlinearity = 0.03), with a nadir of mortality risk around median 15:0. In meta-analyses including our Swedish cohort and 17 cohort, case–cohort, or nested case–control studies, higher 15:0 and 17:0 but not t16:1n-7 were inversely associated with total CVD, with the relative risk of highest versus lowest tertile being 0.88 (0.78, 0.99), 0.86 (0.79, 0.93), and 1.01 (0.91, 1.12), respectively. Dairy fat biomarkers were not associated with all-cause mortality in meta-analyses, although there were ≤3 studies for each biomarker. Study limitations include the inability of the biomarkers to distinguish different types of dairy foods and that most studies in the meta-analyses (including our novel cohort study) only assessed biomarkers at baseline, which may increase the risk of misclassification of exposure levels.ConclusionsIn a meta-analysis of 18 observational studies including our new cohort study, higher levels of 15:0 and 17:0 were associated with lower CVD risk. Our findings support the need for clinical and experimental studies to elucidate the causality of these relationships and relevant biological mechanisms.

Kathy Trieu and co-workers study biomarkers of dairy fat intake and associated health outcomes.     

Hypertensive diseases of pregnancy and risk of hypertension and stroke in later life: results from cohort study

ObjectiveTo examine the association between hypertensive diseases of pregnancy (gestational hypertension and pre-eclampsia) and the development of circulatory diseases in later life.DesignCohort study of women who had pre-eclampsia during their first singleton pregnancy. Two comparison groups were matched for age and year of delivery, one with gestational hypertension and one with no history of raised blood pressure.SettingMaternity services in the Grampian region of Scotland.ParticipantsWomen selected from the Aberdeen maternity and neonatal databank who were resident in Aberdeen and who delivered a first, live singleton from 1951 to 1970.ResultsThere were significant positive associations between pre-eclampsia/eclampsia or gestational hypertension and later hypertension in all measures. The adjusted relative risks varied from 1.13-3.72 for gestational hypertension and 1.40-3.98 for pre-eclampsia or eclampsia. The adjusted incident rate ratio for death from stroke for the pre-eclampsia/eclampsia group was 3.59 (95% confidence interval 1.04 to 12.4).ConclusionsHypertensive diseases of pregnancy seem to be associated in later life with diseases related to hypertension. If greater awareness of this association leads to earlier diagnosis and improved management, there may be scope for reducing a proportion of the morbidity and mortality from such diseases.

What is already known on this topic

Much is known about the effect of cardiovascular risks factors that are shared by men and women, but less on those specific to womenRetrospective studies, based on patient recall, suggest that hypertension in pregnancy may be associated with increased risk of cardiovascular diseases in later life

What this study adds

Prospective recording of blood pressure and proteinuria shows that women who experienced raised blood pressure in pregnancy have a long term risk of hypertensionWomen who experience raise blood pressure in pregnancy have an increased risk of stroke and, to a lesser extent, an increased risk of ischaemic heart diseaseLong term cardiovascular risks are greater for women who had pre-eclampsia than those who experienced gestational hypertension (hypertension without proteinuria)     

Risk Factors for Low Birthweight in Zimbabwean Women: A Secondary Data Analysis

Background

Low birth weight (LBW) remains the main cause of mortality and morbidity in infants, and a problem in the care of pregnant women world-wide particularly in developing countries. The purpose of this study was to describe the socio-demographic, nutritional, reproductive, medical and obstetrical risk factors for delivering a live LBW infant at Harare Maternity Hospital, Zimbabwe.

Methods

A secondary data analysis from data obtained through a questionnaire and delivery records was conducted. Linear regression models with a complimentary log-log link function were used to estimate the relative risks for all LBW, term LBW and preterm LBW.

Results

The frequency of LBW was 16.7%. Lack of prenatal care (adjusted relative risk [ARR] 1.69, 95% CI 1.44, 1.98), mother’s mid-arm circumference below 28.5 cm, (ARR 1.35, 95% CI 1.19, 1.54) and rural residence (ARR 1.22, 95% CI 1.04, 1.40) increased the risk of LBW. Eclampsia, anemia, and ante-partum hemorrhage, were associated with LBW (ARR 2.64, 95% CI 1.30, 5.35; ARR = 2.63, 95% CI 1.16, 5.97; and ARR = 2.39, 95% CI 1.55, 3.68), respectively. Malaria increased the risk of LBW (ARR = 1.89, 95% CI 1.21, 2.96). Prenatal care, infant sex, anemia, antepartum hemorrhage, premature rapture of membranes and preterm labor were associated with the three LBW categories. History of abortion or stillbirth, history of LBW, malaria, eclampsia, and placenta Previa, were associated with all LBW and preterm LBW, while pregnancy induced hypertension, and number of children alive were associated with all LBW and term LBW.

Conclusions

LBW frequency remains high and is associated with nutritive, reproductive, medical and obstetrical factors. Preterm LBW and term LBW have similar and also different risk factors. Understanding the role of different risk factors in these different LBW categories is important if the goal is to reduce LBW frequency, and its complications, in Zimbabwe.     

Long-term prognostic significance of homocysteine in middle-aged and elderly

Objective: We investigated the association among increased levels of plasma homocysteine (Hcy), all-cause mortality, and cardiovascular events. Methods: Hcy was measured in 670 middle-aged and elderly subjects with no previous manifest cardiovascular disease. The follow-up period was 15 years. Results: Subjects with Hcy?≥?10.8?μmol/l (n?=?231) had a significant higher incidence of all-cause mortality (p?<?0.001) and CV events (p?<?0.001) compared with subjects with Hcy?<?10.8?μmol/l (n?=?439). However, there was no association on high levels of Hcy and VTE events or stroke. Conclusion: Increased levels of Hcy are associated with all-cause mortality and CV events.     

Treatment trajectory of tobacco-related cancer patients: A study in Assam,India

BackgroundIn India, more than half of the total cancer cases are diagnosed at an advanced stage resulting in a high mortality rate. Early diagnosis and proper treatment may result in reduced mortality. Understanding the treatment trajectory followed by a patient is important for reducing diagnostic delay which may result in improved prognosis and treatment. With this background, the current study attempts to understand the treatment-seeking processes of Tobacco-related Cancer (TRC) patients in the state of Assam.MethodsExplanatory Sequential Mixed design was adopted for the study. In the first phase of the study, 100 participants were interviewed using an interview schedule and then 11 in-depth interviews were conducted in the later phase to understand the subject matter in more depth.ResultsThe study revealed that the initial point of contact for seeking help for most of the participants was their family, which was followed by an alternative system of medicine including faith healers and quacks. Participants with a lower level of literacy and economic instability were seen to have approached family members, faith healers and quacks more as compared to the people with a higher level of literacy and economic stability who approached health professionals, friends, and others for initial help-seeking. Also, an association between causal health beliefs and treatment choices of the patients were discovered.ConclusionsThe study suggests addressing the beliefs and practices associated with cancer care (both modern and traditional) by engaging mass awareness. Need for designing cancer-education programmes for the general population was also advocated.     

Objectively Measured Daily Steps and Subsequent Long Term All-Cause Mortality: The Tasped Prospective Cohort Study

BackgroundSelf–reported physical activity has been inversely associated with mortality but the effect of objectively measured step activity on mortality has never been evaluated. The objective is to determine the prospective association of daily step activity on mortality among free-living adults.ConclusionsHigher daily step count was linearly associated with subsequent long term mortality among free living adults. These data are the first to quantify mortality reductions using an objective measure of physical activity in a free living population. They strongly underscore the importance of physical inactivity as a major public health problem.     

Parental death in childhood and pathways to increased mortality across the life course in Stockholm,Sweden: A cohort study

BackgroundPrevious studies have shown that the experience of parental death during childhood is associated with increased mortality risk. However, few studies have examined potential pathways that may explain these findings. The aim of this study is to examine whether familial and behavioural factors during adolescence and socioeconomic disadvantages in early adulthood mediate the association between loss of a parent at age 0 to 12 and all-cause mortality by the age of 63.Methods and findingsA cohort study was conducted using data from the Stockholm Birth Cohort Multigenerational Study for 12,615 children born in 1953, with information covering 1953 to 2016. Familial and behavioural factors at age 13 to 19 included psychiatric and alcohol problems in the surviving parent, receipt of social assistance, and delinquent behaviour in the offspring. Socioeconomic disadvantage in early adulthood included educational attainment, occupational social class, and income at age 27 to 37. We used Cox proportional hazard regression models, combined with a multimediator analysis, to separate direct and indirect effects of parental death on all-cause mortality.Among the 12,582 offspring in the study (men 51%; women 49%), about 3% experienced the death of a parent in childhood. During follow-up from the age of 38 to 63, there were 935 deaths among offspring. Parental death was associated with an elevated risk of mortality after adjusting for demographic and household socioeconomic characteristics at birth (hazard ratio [HR]: 1.52 [95% confidence interval: 1.10 to 2.08, p-value = 0.010]). Delinquent behaviour in adolescence and income during early adulthood were the most influential mediators, and the indirect associations through these variables were HR 1.03 (1.00 to 1.06, 0.029) and HR 1.04 (1.01 to 1.07, 0.029), respectively. After accounting for these indirect paths, the direct path was attenuated to HR 1.35 (0.98 to 1.85, 0.066). The limitations of the study include that the associations may be partly due to genetic, social, and behavioural residual confounding, that statistical power was low in some of the subgroup analyses, and that there might be other relevant paths that were not investigated in the present study.ConclusionsOur findings from this cohort study suggest that childhood parental death is associated with increased mortality and that the association was mediated through a chain of disadvantages over the life course including delinquency in adolescence and lower income during early adulthood. Professionals working with bereaved children should take the higher mortality risk in bereaved offspring into account and consider its lifelong consequences. When planning and providing support to bereaved children, it may be particularly important to be aware of their increased susceptibility to delinquency and socioeconomic vulnerability that eventually lead to higher mortality.

In this cohort study, Ayako Hiyoshi and colleagues show associations between parental death in a child’s life and mortality risk later in that child’s life.