Number of children and later-life mortality among Finns born 1938-50

Fatherhood timing and men's midlife earnings: A within-family study of Finnish cohorts born in 1938-50

Fathers tend to achieve higher earnings than childless men, but there is limited evidence on the associations between fatherhood timing and men's later earnings. Using a longitudinal census-based sample of Finnish men, including a subsample of brothers, we investigated fatherhood timing and men's midlife earnings using both between- and within-family models. Earnings around age 50 were lower among adolescent and young fathers than for men who became fathers at ages 25-29 or later, but these associations became negligible after accounting for measured confounders and unobserved familial confounding. Overall, our findings highlight the important roles of selection into early childbearing and into childlessness. At the population level, early fatherhood was associated with clear negative distributional shifts in fathers' midlife earnings. However, among all men, any influence of fatherhood timing on men's midlife earnings distribution paled in comparison with that of childlessness.

Health outcomes of only children across the life course: An investigation using Swedish register data

Only children (with no full biological siblings) are a growing subgroup in many high-income settings. Previous studies have largely focused on the short-term developmental outcomes of only children, but there is limited evidence on their health outcomes. Using Swedish population register data for cohorts born 1940-75, we compare the health of only children with that of children from multi-child sibling groups, taking into account birth order, family size, and presence of half-siblings. Only children showed lower height and fitness scores, were more likely to be overweight/obese in late adolescence, and experienced higher later-life mortality than those with one or two siblings. However, only children without half-siblings were consistently healthier than those with half-siblings, suggesting that parental disruption confers additional disadvantages. The health disadvantage was attenuated but not fully explained by adjustment for parental characteristics and after using within-family maternal cousin comparison designs.

What have we learned about mortality patterns over the past 25 years?

In this paper, I examine progress in the field of mortality over the past 25 years. I argue that we have been most successful in taking advantage of an increasingly data-rich environment to improve aggregate mortality models and test pre-existing theories. Less progress has been made in relating our estimates of mortality risk at the individual level to broader mortality patterns at the population level while appropriately accounting for contextual differences and compositional change. Overall, I find that the field of mortality continues to be highly visible in demographic journals, including Population Studies. However much of what is published today in field journals could just as easily appear in neighbouring disciplinary journals, as disciplinary boundaries are shrinking.

The association between parity, CVD mortality and CVD risk factors among Norwegian women and men

BACKGROUND

Several studies have shown that women and men with two children have lower mortality than the childless, but there is less certainty about mortality, including CVD mortality, at higher parities and meagre knowledge about factors underlying the parity-mortality relationship.

METHODS

The association between parity and CVD mortality was analyzed by estimating discrete-time hazard models for women and men aged 40-80 in 1975-2015. Register data covering the entire Norwegian population were used, and the models included a larger number of relevant sociodemographic control variables than in many previous studies. To analyze the relationship between parity and seven CVD risk factors, logistic models including the same variables as the mortality models were estimated from the CONOR collection of health surveys, linked to the register data.

RESULTS

Men (but not women) who had four or more children had higher mortality from CVD than those with two, although this excess mortality was not observed for the heart disease sub-group. Overweight, possibly in part a result of less physical activity, seems to play a role in this. All CVD risk factors except smoking and alcohol may contribute to the relatively high CVD mortality among childless.

CONCLUSIONS

Childbearing is related to a number of well-known CVD risk factors, and becoming a parent or having an additional child is, on the whole, associated with lower-or at least not higher-CVD mortality in Norway. However, for men family sizes beyond three children are associated with increased CVD mortality, with risks of overweight one possible pathway.

Cross-Sectional Average Length of Life Childless

Increases in the average age at first birth and in the proportion of women remaining childless have extended the total number of years that women spend childless during their reproductive lifetime in several countries. To quantify the number of years that reproductive-age women live without children, we introduce the cross-sectional average length of life childless (CALC). This measure includes all the age-specific first-birth information available for the cohorts present at time t; it is a period measure based on cohort data. Using the Human Fertility Database, CALC is calculated for the year 2015 for all countries with long enough histories of fertility available. Results show that women in the majority of the studied countries spend, on average, more than half of their reproductive lives childless. Furthermore, the difference between CALCs in two countries can be decomposed to give a clear visualization of how each cohort contributes to the difference in the duration of the length of childless life in those populations. Our illustration of the decomposition shows that (1) in recent years, female cohorts in Japan and Spain at increasingly younger ages have been contributing to more years of childless life compared with those in Sweden, (2) the United States continues to represent an exception among the high-income countries with a low expectation for childless life of women, and (3) Hungary experienced a strong period effect of the recent Great Recession. These examples show that CALC and its decomposition can provide insights into first-birth patterns.

Male childlessness as independent predictor of risk of cardiovascular and all-cause mortality: A population-based cohort study with more than 30 years follow-up

In a recent population-based study, an elevated risk of the Metabolic syndrome (MetS) and type 2 diabetes was found in childless men compared to those who have fathered one or more children. Therefore, by using a larger cohort of more than 22 000 men from the Malmo Preventive Project (MPP) we aimed to expand our observations in order to evaluate the metabolic profile of childless men and to evaluate if childlessness is an additional and independent predictor of major adverse cardiovascular events (MACE), mortality and incident diabetes when accounting for well-known biochemical, anthropometric, socio-economic and lifestyle related known risk factors. Logistic regression was used to assess risk of MACE, diabetes and MetS at baseline. Multivariate Cox regression was used to evaluate the risks of MACE and mortality following the men from baseline screening until first episode of MACE, death from other causes, emigration, or end of follow-up (31^st December 2016) adjusting for age, family history, marital status, smoking, alcohol consumption, educational status, body mass index, prevalent diabetes, high blood lipids, increased fasting glucose and hypertension. Childless men presented with a worse metabolic profile than fathers at the baseline examination, with elevated risk of high triglycerides, odds ratio (OR) 1.24 (95%CI: 1.10–1.42), high fasting glucose OR 1.23 (95%CI: 1.05–1.43) and high blood pressure, OR 1.28 (95%CI: 1.14–1.45), respectively. In the fully adjusted prospective analysis, childless men presented with elevated risk of cardiovascular mortality, HR: 1.33 (95% CI: 1.18–1.49) and all-cause mortality, HR 1.23 (95%CI: 1.14–1.33), respectively. In conclusion, these results add to previous studies showing associations between male reproductive health, morbidity and mortality. Male childlessness, independently of well-known socio-economic, behavioral and metabolic risk factors, predicts risk of cardiovascular disease and mortality. Consequently, this group of men should be considered as target population for preventive measures.

Alcohol-related mortality following the loss of a child: a register-based follow-up study from Norway

OBJECTIVES

The death of one's child is one of the most stressful events a person can experience. Research has shown that bereaved parents have a higher mortality than non-bereaved parents. This increased mortality might partly be caused directly by long-term stress. However, changes in health behaviour such as an increase in alcohol consumption might also play a role. This study examines the association between losing a child and alcohol-related mortality. In addition to Cox regression models using data covering the entire Norwegian adult population, we employ sibling fixed-effect models in order to partly control for genes and childhood experiences that might be associated with both losing a child and alcohol-related mortality.

DESIGN

A follow-up study between 1986 and 2014 based on Norwegian register data.

SETTING

Norway.

PARTICIPANTS

The entire Norwegian adult population.

PRIMARY OUTCOME MEASURE

Alcohol-related mortality.

RESULTS

An increased alcohol-related mortality was found among parents who had experienced the death of a child. The HR of alcohol-related mortality among those bereaved of a child was 1.59 (95% CI 1.48 to 1.71) compared with non-bereaved parents, for women 2.03 (95% CI 1.78 to 2.32) and for men 1.46 (95% CI 1.34 to 1.59). After including sibling fixed effects, the HR of alcohol-related mortality among parents who had lost a child was 1.30 (95% CI 1.03 to 1.64).

CONCLUSIONS

This study provides evidence of an elevated alcohol-related mortality among parents who have lost a child compared with non-bereaved parents. Although strongly attenuated, there is still an association when adjusting for genetic predisposition for alcohol problems as well as childhood environment using sibling fixed-effect models.

Men's age at first birth and alcohol-related morbidity and mortality among siblings

BACKGROUND

Men's age at first birth may negatively or positively affect alcohol-related morbidity and mortality, although little evidence is available.

METHODS

We used register data of over 22,000 brothers to analyze the associations between age at first birth and alcohol-related morbidity and mortality from the age of 35 until the age of 60 or 72. We employed conventional Cox models and inter-sibling models, which allowed adjustment for unobserved social and genetic characteristics shared by brothers.

RESULTS

The findings show that men's age at first birth was inversely associated with alcohol-related morbidity and mortality, independent of unobserved characteristics shared by brothers and of observed demographic confounders. Men who had their first child late at 35-45 years experienced lower alcohol-related morbidity and mortality (hazard ratio (HR) = 0.57, 95 % confidence interval (CI) = 0.43, 0.75) than men who had their first child at 25-29. Men who had their first child before age 20 had the highest morbidity and mortality among all fathers (HR = 1.36, 95 % CI = 1.09, 1.69), followed by men who had their child at 20-24 (HR = 1.12, 95 % CI = 1.00, 1.25).

CONCLUSIONS

The results imply that the inverse association between men's age at first birth and alcohol-related morbidity and mortality is not driven by familial characteristics.

Parents survive longer after stroke than childless individuals: a prospective cohort study of Swedes over the age of 65

BACKGROUND

Parents have lower mortality than childless individuals, and one possible explanation is support provided by adult children. Since stroke often results in functional limitations, support from children may be of particular importance. Here, we examine whether the presence of children matters for survival after stroke among older Swedish men and women.

METHODS

This prospective cohort study linked data from several Swedish population registers. Individuals aged 65 years and older hospitalized for their first ischemic stroke between 1998 and 2002 (33 960 men and 36 189 women) were followed 12 years for survival. Hazard ratios for all-cause mortality were calculated by number of children using Cox proportional hazard regression stratified by sex and marital status and adjusted for education, income and comorbidities.

RESULTS

Childlessness and having only one child was associated with higher mortality after stroke compared with having two children among men and women. The relative survival disadvantage of childless individuals was largest among married women [HR 1.28 (1.18-1.39)] and smallest among married men [1.09 (1.03-1.15)]. The differences in predicted median survival between childless individuals and those with two children were 4 and 7 months among married and unmarried men, and 15 and 9 months among married and unmarried women, respectively.

CONCLUSIONS

Having children is associated with a longer survival after stroke among men and women regardless of marital status. Our findings further suggest that the presence of children is especially connected to married women's survival. These results may have implications for the improvement of informal care for childless older individuals.

The role of children and their socioeconomic resources for the risk of hospitalisation and mortality - a nationwide register-based study of the total Swedish population over the age 70

Background

Previous studies have shown that mortality in old age is associated with both number of children and their socioeconomic resources. The underlying mechanisms are unclear, as well as when during the process of health deterioration the advantage of parents over non-parents arises. This study aims to examine how the number of children and their socioeconomic resources are associated with different health outcomes among their parents, namely the hazard for i) first hospitalisation, ii) re-admission, iii) mortality after first hospitalisation, and iv) overall mortality.

Method

This longitudinal cohort study includes all individuals born 1920–1940 who were living in Sweden at age 70 years (890,544 individuals). Individuals were linked to their offspring and spouse using administrative registers and followed for up to 25 years. Associations were estimated using multivariable Cox models adjusted for index persons’ education and income, marital status, their partners’ education, and age at first birth.

Results

In this study, having children was associated with reduced mortality risk of their parents, but not with the risk of being hospitalised, which increased as number of children increased. A higher education of children was protective for all parental outcomes independent of number of children and their financial resources. In fact, income of the children was only weakly associated with the health of their parents.

Conclusions

The benefit of having children compared to childlessness for health in old age seems to arise once individuals have become ill rather than before. Children’s education is important for parental health and mortality, in fact more important than the number of children itself in this Swedish cohort.

Electronic supplementary material

The online version of this article (10.1186/s12877-019-1134-y) contains supplementary material, which is available to authorized users.

The parental co-immunization hypothesis: An observational competing risks analysis

The main interest of this study is the hypothesis that contact with small children may be beneficial for the parents’ later health and mortality (because of changes in their immune system). For this purpose, we document the relationship of a set of individual characteristics—including parenthood and marital state—and socioeconomic status with an individual’s cause of death. Using a novel and rich data set made available by the Office for National Statistics Longitudinal Study (ONS-LS), which follows 1% of the population of England and Wales along five census waves 1971, 1981, 1991, 2001, and 2011, our competing risks analysis yields several striking results: (1) Females with children have a 72.5% reduced risk of dying of cancer compared to childless females (for childless females of age 70, this corresponds to a risk of dying of cancer of 1.3% compared to a risk of about 1.3 × 0.275 = 0.4% for females with children). (2) Males have a 171% increased chance of dying of cancer when they are married (e.g., a baseline probability of 1.2% when 75 year old) compared to unmarried males. (3) Females with children have only a 34% risk of dying of heart disease (corresponding to a conditional probability of 0.3% when aged 65) relative to females without children and (4) a 53% chance of dying of infections (i.e., 0.1% at 65 years of age) compared to the risk for females without children. (5) At the same age, married men have an increased expectation of 123% of dying of heart disease (corresponding to an expected death probability of 0.7%) compared to unmarried men. (6) High income and house ownership is always associated with higher survival but less so than having children. While these results document a relationship between the presence of children and mortality, the specific transmission mechanisms remain unclear and we cannot make causality assertions.

Hearing loss, family status and mortality - Findings from the HUNT study, Norway

Hearing loss as well as being single has been associated with an increased risk of all-cause mortality. The purpose of the study is to assess whether being single or childless moderates the elevated risk of mortality in hearing impaired. The Nord-Trøndelag hearing Loss Study examined 50,462 persons above 20 years of age during 1996-1998. The Norwegian Cause of Death Registry was used to identify deaths until 2016. Data on marital status was obtained from the Norwegian Population Registry. Hearing loss was defined as the pure-tone average (0.5-4 kHz) of hearing thresholds greater than 25 dB hearing level (dB HL) in the better ear. Associations between hearing loss and mortality risk were estimated using Cox regression after an average follow-up of 17.6 years. Hearing loss was associated with increased risk of all-cause mortality before 75 years of age (hazard ratio [HR] 1.3, 95% confidence interval [CI] 1.2-1.4) and cardiovascular mortality (HR 1.8, 95% CI 1.5-2.1) but not with cancer mortality (HR 1.1, 95% CI 0.9-1.3) or mortality due to injuries (HR 1.4, 95% CI 0.9-2.3). Adjusting for socio-economic characteristics, cardiovascular risk-factors, diseases, and family status, reduced the associations for all-cause mortality (HR 1.1, 95% CI 1.0-1.2) and cardiovascular mortality (HR 1.4, 95% CI 1.2-1.6). The adjusted mortality risk was found to be significantly related to family status. Being divorced raised the mortality risk associated with hearing loss among those below 75 years of age. There was a similar tendency also for being childless, although this was only significant for females. There was also a trend for a lower mortality related to hearing loss in subjects with a well-hearing partner. More focus should be given to those who lack a family when having functional limitations such as hearing impairment.

Fertility History and Physical and Mental Health Changes in European Older Adults

Previous studies have shown that aspects of reproductive history, such as earlier parenthood and high parity, are associated with poorer health in mid and later life. However, it is unclear which dimensions of health are most affected by reproductive history, and whether the pattern of associations varies for measures of physical, psychological and cognitive health. Such variation might provide more insight into possible underlying mechanisms. We use longitudinal data for men and women aged 50–79 years in ten European countries from the Survey of Health, Ageing and Retirement in Europe to analyse associations between completed fertility history and self-reported and observed health indicators measured 2–3 years apart (functional limitations, chronic diseases, grip strength, depression and cognition), adjusting for socio-demographic, and health factors at baseline. Using multiple imputation and pattern mixture modelling, we tested the robustness of estimates to missing data mechanisms. The results are partly consistent with previous studies and show that women who became mothers before age 20 had worse functional health at baseline and were more likely to suffer functional health declines. Parents of 4 or more children had worse physical, psychological and cognitive health at baseline and were more likely to develop circulatory disease over the follow-up period. Men who delayed fatherhood until age 35 or later had better health at baseline but did not experience significantly different health declines. This study improves our understanding of linkages between fertility histories and later life health and possible implications of changes in fertility patterns for population health. However, research ideally using prospective life course data is needed to further elucidate possible mechanisms, considering interactions with partnership histories, health behaviour patterns and socio-economic trajectories.

U-shaped association between fertility and mortality in a community-based sample of Japanese women

BACKGROUND

Prospective cohort studies of contemporary populations in both Western and Asian settings have reported a U-shaped association between fertility and mortality. We examined whether an association exists between fertility and all-cause and cause-specific mortality in a sample of Japanese women.

METHODS

A prospective cohort study was conducted in one rural and one urban community in Gunma Prefecture, Japan, in 1993. A follow-up survey was conducted in the year 2000 in 4858 women aged 47-77 years, and information on demographic and lifestyle characteristics was collected. Mortality and migration data through December 2008 were obtained. A Cox proportional hazard model was used to examine the relationship between parity and mortality.

RESULTS

Compared with women with 2-4 children (reference group), higher total mortality was observed among women with 0-1 or 5+ children. Low (HR 1.7, 95% CI 1.2 to 2.3) and high (HR 2.1, 95% CI 1.0 to 4.7) parities were both associated with higher all-cause mortality even after adjusting for potential confounders. Mortality due to ischaemic heart disease exhibited a significant association with parity; the HRs were 3.2 (95% CI 1.1 to 9.2) for women with 0-1 child and 8.7 (95% CI 1.7 to 45.5) for women with 5 or more children. No significant association was observed for mortality from malignancies, cancer of the digestive system, cardiovascular disease or cerebrovascular disease.

CONCLUSIONS

There exists a U-shaped association between parity and all-cause mortality and cause-specific mortality due to ischaemic heart disease among Japanese women.

Age Trajectories of Physical Health Among Older Adults of Mexican Descent: Implications of Immigrant Status, Age at Immigration, and Gender

OBJECTIVE

This study examines consequences of immigrant status, age at immigration, and gender on age trajectories of activities of daily living (ADL) limitations and chronic conditions among older adults of Mexican descent.

METHOD

This research draws on 7 waves of the Hispanic Established Populations for the Epidemiologic Study of the Elderly and employs growth curve models.

RESULTS

All men had similar age trajectories of ADL limitations, regardless of immigrant status and age at immigration. All women experienced steeper increases in ADL limitations, although U.S.-born women and those who immigrated by age 19 had lower initial levels. Men who immigrated between ages 20 and 49 had steeper increases in chronic conditions, despite lower initial levels. U.S.-born women and those women who immigrated by age 50 had more chronic conditions at age 65.

DISCUSSION

This study highlights the multidimensional nature of physical health by demonstrating that immigrant status-gender disparities can vary by the health outcome examined.