Overweight and obesity at age 19 after pre-natal famine exposure.

BACKGROUND: Weight for height has been used in the past as an indicator of obesity to report that prenatal exposure to the Dutch famine of 1944-1945 determined subsequent obesity. Further evaluation is needed as unresolved questions remain about the possible impact of social class differences in fertility decline during the famine and because being overweight is now defined by a Body Mass Index (BMI: kg/m2) from 25 to <30 and obesity by a BMI of 30 or more. METHODS: We studied heights and weights of 371,100 men in the Netherlands born between 1943 and 1947 and examined for military service at age 19. This group includes men with and without prenatal exposure to the Dutch famine. RESULTS: There was a 1.3-fold increase in the risk of being overweight or obese in young adults at age 19 after prenatal famine exposure in early gestation. The increase was only seen in sons of manual workers born in the large cities of Western Netherlands and not among those born in smaller cities or rural areas in the West. Social class differentials in fertility decline during the famine did not bias study results. CONCLUSIONS: The long-term adverse impact of prenatal famine on later life type 2 diabetes and mortality through age 63 is already showing at age 19 in this population as a significant increase in overweight risk.

Parental lifespan and the likelihood of reaching the age of 90 years in the Netherlands Cohort Study.

AIM: Growing evidence suggests an association between parental longevity and lifespan of subsequent generations. We aimed to reproduce earlier findings, showing a positive association between parental longevity and offspring's longevity. Additionally, we investigated whether this is mainly driven by the maternal or paternal germline in male and female offspring. METHODS: For these analyses, data from the oldest birth cohort (1916-17) of the Netherlands Cohort Study was used. Participants filled in a baseline questionnaire in 1986 (at age 68-70 years). Follow up for vital status information until the age of 90 years (2006-07) was >99.9% complete. Multivariable-adjusted Cox regression analyses with a fixed follow-up time were based on 2368 men and 2657 women with complete parental survival data and relevant confounders to calculate risk ratios (RR) of reaching longevity. RESULTS: In age-adjusted models, paternal and maternal age at death were significantly positively associated with reaching 90 years in both male and female offspring. In male offspring, paternal age at death (≥90 years vs <80 years) showed the strongest association with survival to 90 years (RR 1.42, 95% CI 1.07-1.89), after confounder correction. In female offspring, maternal age at death (≥90 years vs <80 years) showed the strongest association with survival to 90 years (RR 1.20, 95% CI 1.04-1.40). DISCUSSION: After confounder adjustment, stronger and significant associations were observed between paternal lifespan and male offspring longevity, and maternal lifespan and female offspring longevity. Future research should investigate through which pathways a longer lifespan of parents is transmitted to their offspring. Geriatr Gerontol Int 2021; 21: 215-221.

Female reproductive factors and the likelihood of reaching the age of 90 years. The Netherlands Cohort Study.

OBJECTIVES: The aim of this study was to prospectively assess the relationship between several reproductive factors in women and the likelihood of reaching the age of 90 years (achieving longevity). STUDY DESIGN: For this study, data from the oldest birth cohort (1916-17) of the prospective Netherlands Cohort Study (NLCS) were used. These participants filled in a baseline questionnaire in 1986 (at age 68-70 years). Follow-up for vital status information until the age of 90 years (2006-07) was >99.9% complete. MAIN OUTCOME MEASURES: Multivariable-adjusted Cox regression analyses with a fixed follow-up time were based on 2,697 women with complete exposure and co-variable data to calculate risk ratios (RR) of reaching age 90. RESULTS: No associations were observed between the likelihood of reaching the age of 90 years, and age at menarche, age at menopause, parity, menstrual lifespan, and oral contraceptive use after adjustment for potential confounders. A later age at first childbirth pointed towards a higher chance of achieving longevity (age ≥30 vs. 20-24; RR,1.17; 95%CI,0.98-1.39). Ever-use of hormone replacement therapy (HRT) was significantly associated with a higher chance of achieving longevity compared with never HRT-users, but only in women who had had an early menopause (<50 years)(RR,1.32; 95% CI, 1.07-1.61). CONCLUSION: Age at first childbirth, and ever-use of HRT in women with an early menopause (<50 years) were associated with the likelihood of reaching the age of 90 years.

The 100-plus Study of cognitively healthy centenarians: rationale, design and cohort description.

Although the incidence of dementia increases exponentially with age, some individuals reach more than 100 years with fully retained cognitive abilities. To identify the characteristics associated with the escape or delay of cognitive decline, we initiated the 100-plus Study ( www.100plus.nl ). The 100-plus Study is an on-going prospective cohort study of Dutch centenarians who self-reported to be cognitively healthy, their first-degree family members and their respective partners. We collect demographics, life history, medical history, genealogy, neuropsychological data and blood samples. Centenarians are followed annually until death. PET-MRI scans and feces donation are optional. Almost 30% of the centenarians agreed to post-mortem brain donation. To date (September 2018), 332 centenarians were included in the study. We analyzed demographic statistics of the first 300 centenarians (25% males) included in the cohort. Centenarians came from higher socio-economic classes and had higher levels of education compared to their birth cohort; alcohol consumption of centenarians was similar, and most males smoked during their lifetime. At baseline, the centenarians had a median MMSE score of 25 points (IQR 22.0-27.5); most centenarians lived independently, retained hearing and vision abilities and were independently mobile. Mortality was associated with cognitive functioning: centenarians with a baseline MMSE score ≥ 26 points had a mortality percentage of 17% per annual year  in the second year after baseline, while centenarians with a baseline MMSE score < 26 points had a mortality of  42% per annual year (p = 0.003). The cohort was 2.1-fold enriched with the neuroprotective APOE-ε2 allele relative to 60-80 year-old population controls (p = 4.8 × 10-7), APOE-ε3 was unchanged and the APOE-ε4 allele was 2.3-fold depleted (p = 6.3 × 10-7). Comprehensive characterization of the 100-plus cohort of cognitively healthy centenarians might reveal protective factors that explain the physiology of long-term preserved cognitive health.

[Medical training did not give survival advantage; life expectancy of Dutch medical professionals born between 1550 and 1909]. / Medische opleiding gaf geen overlevingsvoordeel.

OBJECTIVE: To examine if, over a period of centuries, the Dutch medical establishment enjoyed a survival advantage over a population group with a comparable social background and level of education. DESIGN: Retrospective database research. METHOD: We used documents which provided data on the births and deaths of 15,649 male and 659 female medical professionals and of 15,304 male clergy. We calculated the remaining life expectancy at the age of 25 of those generations born between the middle of the 16th century and the beginning of the 20th century. We applied event history analysis to estimate remaining life expectancy, dependently of survival at the age of 25. In doing this we applied Gompertz distribution and made a maximum likelihood estimation. RESULTS: From the middle of the 16th century onwards, the development of the life expectancy of medical professionals and clergy was comparable; it was characterised by a continuing increase in remaining life expectancy which was only interrupted in those generations who were confronted with a series of epidemics. The level of the remaining life expectancy was also comparable. Only in the generation born in the first decade of the 20th century did the life expectancy of medical professionals become on par with that of the total male population. The remaining life expectancy of female medical professionals born from 1850 onwards was higher than that of the total female population. CONCLUSION: For a long time, medical training conferred no advantage on survival.

Agency in Fertility Decisions in Western Europe During the Demographic Transition: A Comparative Perspective.

We use a set of linked reproductive histories taken from Sweden, the Netherlands, and Spain for the period 1871-1960 to address key issues regarding how reproductive change was linked specifically to mortality and survivorship and more generally to individual agency. Using event-history analysis, this study investigates how the propensity to have additional children was influenced by the number of surviving offspring when reproductive decisions were made. The results suggest that couples were continuously regulating their fertility to achieve reproductive goals. Families experiencing child fatalities show significant increases in the hazard of additional births. In addition, the sex composition of the surviving sibset also appears to have influenced reproductive decisions in a significant but changing way. The findings offer strong proof of active decision-making during the demographic transition and provide an important contribution to the literature on the role of mortality for reproductive change.

Can resource dilution explain differences in height by birth order and family size? A study of 389,287 male recruits in twentieth-century Netherlands.

'Resource dilution' has been invoked as a possible mechanism to explain the inverse relation between sibship size and sibling heights in European populations (Öberg, 2015). Alternative explanations include confounding of the relation by other measured or unmeasured family characteristics including socio-economic position or birth order. It is difficult to quantify the contribution of any factor in isolation. To examine the question, we accessed data from the national birth cohort of 389,287 Dutch conscripts born in 1944-1947 and examined for military service at age 18. The records include all men of Dutch nationality born between January 1, 1944 and December 31, 1947 examined for military service in the Netherlands. The birth cohorts provide a well-defined study population to reliably assess the impact of family size and birth order on adult height, accounting for potential confounders. The cohorts include a large number of high-parity families, provide reliable information on both family size and birth order, and differentiate between all birth orders. The military examinations provide reliable information on height for all study subjects and uniform measurements at age 18. We show that recruits from larger families are shorter than recruits from smaller families; that birth order effects are small in relation to family size effects; and that birth order and family size effects are comparable in recruits from higher to lower socio-economic backgrounds. Recruits from higher backgrounds are significantly taller however. Our findings are compatible with a 'resource dilution' hypothesis, but our data provide no information on any specific differences in the childhood environment in terms of nutrition, education, or other family behaviours could explain the observed height differences at age 18. Additional studies will be needed to identify what differences in specific family behaviours could lead to changes in height development.

War-related excess mortality in The Netherlands, 1944-45: New estimates of famine- and non-famine-related deaths from national death records.

Despite there being several estimates for famine-related deaths in the west of The Netherlands during the last stage of World War II, no such information exists for war-related excess mortality among the civilian population from other areas of the country. Previously unavailable data files from Statistics Netherlands allow researchers to estimate the number of war-related excess deaths during the last stage of the war in the whole country. This study uses a seasonal-adjusted mortality model combined with a difference-in-difference approach to estimate the number of excess deaths in the period between January 1944 and July 1945 at a total of close to 91,000 (75%) excess deaths. Almost half of all war-related excess mortality during the last year of the war occurred outside the west.

Early-life conditions and adult mortality decline in Dutch cohorts born 1812-1921.

Mounting evidence suggests that early-life conditions have an enduring effect on an individual's mortality risks as an adult. The contribution of improvements in early-life conditions to the overall decline in adult mortality, however, remains a debated issue. We provide an estimate of the contribution of improvements in early-life conditions to mortality decline after age 30 in Dutch cohorts born between 1812 and 1921. We used two proxies for early-life conditions: median height and early-childhood mortality. We estimate that improvements in early-life conditions contributed more than five years or about a third to the rise in women's life expectancy at age 30. Improvements in early-life conditions contributed almost three years or more than a quarter to the rise in men's life expectancy at age 30. Height appears to be the more important of the two proxies for early-life conditions.

The Trade-Off between Female Fertility and Longevity during the Epidemiological Transition in the Netherlands.

Several hypotheses have been put forward to explain the relationship between women's fertility and their post-reproductive longevity. In this study, we focus on the disposable soma theory, which posits that a negative relationship between women's fertility and longevity can be understood as an evolutionary trade-off between reproduction and survival. We examine the relationship between fertility and longevity during the epidemiological transition in the Netherlands. This period of rapid decline in mortality from infectious diseases offers a good opportunity to study the relationship between fertility and longevity, using registry data from 6,359 women born in The Netherlands between 1850 and 1910. We hypothesize that an initially negative relationship between women's fertility and their longevity gradually turns less negative during the epidemiological transition, because of decreasing costs of higher parities. An initially inversed U-shaped association between fertility and longevity changes to zero during the epidemiological transition. This does suggest a diminishing environmental pressure on fertility. However, we find no evidence of an initial linear trade-off between fertility and post-reproductive survival.

Gains in Life Expectancy Associated with Higher Education in Men.

BACKGROUND: Many studies show large differences in life expectancy across the range of education, intelligence, and socio-economic status. As educational attainment, intelligence, and socio-economic status are highly interrelated, appropriate methods are required to disentangle their separate effects. The aim of this paper is to present a novel method to estimate gains in life expectancy specifically associated with increased education. Our analysis is based on a structural model in which education level, IQ at age 18 and mortality all depend on (latent) intelligence. The model allows for (selective) educational choices based on observed factors and on an unobserved factor capturing intelligence. Our estimates are based on information from health examinations of military conscripts born in 1944-1947 in The Netherlands and their vital status through age 66 (n = 39,798). RESULTS: Our empirical results show that men with higher education have lower mortality. Using structural models to account for education choice, the estimated gain in life expectancy for men moving up one educational level ranges from 0.3 to 2 years. The estimated gain in months alive over the observational period ranges from -1.2 to 5.7 months. The selection effect is positive and amounts to a gain of one to two months. Decomposition of the selection effect shows that the gain from selection on (latent) intelligence is larger than the gain from selection on observed factors and amounts to 1.0 to 1.7 additional months alive. CONCLUSION: Our findings confirm the strong selection into education based on socio-economic status and intelligence. They also show significant higher life expectancy among individuals with higher education after the selectivity of education choice has been taken into account. Based on these estimates, it is plausible therefore that increases in education could lead to increases in life expectancy.

The Adoption of Smoking and Its Effect on the Mortality Gender Gap in Netherlands: A Historical Perspective.

We examine in depth the effect of differences in the smoking adoption patterns of men and women on the mortality gender gap in Netherlands, employing a historical perspective. Using an indirect estimation technique based on observed lung cancer mortality from 1931 to 2012, we estimated lifetime smoking prevalence and smoking-attributable mortality. We decomposed the sex difference in life expectancy at birth into smoking-related and nonsmoking-related overall and cause-specific mortality. The smoking epidemic in Netherlands, which started among men born around 1850 and among women from birth cohort 1900 onwards, contributed substantially to the increasing sex difference in life expectancy at birth from 1931 (1.3 years) to 1982 (6.7 years), the subsequent decline to 3.7 years in 2012, and the high excess mortality among Dutch men born between 1895 and 1910. Smoking-related cancer mortality contributed most to the increase in the sex difference, whereas smoking-related cardiovascular disease mortality was mainly responsible for the decline from 1983 onwards. Examining nonsmoking-related (cause-specific) mortality shed new light on the mortality gender gap and revealed the important role of smoking-related cancers, the continuation of excess mortality among women aged 40-50, and a smaller role of biological factors in the sex difference than was previously estimated.

Prenatal famine exposure and adult mortality from cancer, cardiovascular disease, and other causes through age 63 years.

Nutritional conditions in early life may affect adult health, but prior studies of mortality have been limited to small samples. We evaluated the relationship between pre-/perinatal famine exposure during the Dutch Hunger Winter of 1944-1945 and mortality through age 63 years among 41,096 men born in 1944-1947 and examined at age 18 years for universal military service in the Netherlands. Of these men, 22,952 had been born around the time of the Dutch famine in 6 affected cities; the remainder served as unexposed controls. Cox proportional hazards models were used to estimate hazard ratios for death from cancer, heart disease, other natural causes, and external causes. After 1,853,023 person-years of follow-up, we recorded 1,938 deaths from cancer, 1,040 from heart disease, 1,418 from other natural causes, and 523 from external causes. We found no increase in mortality from cancer or cardiovascular disease after prenatal famine exposure. However, there were increases in mortality from other natural causes (hazard ratio = 1.24, 95% confidence interval: 1.03, 1.49) and external causes (hazard ratio = 1.46, 95% confidence interval: 1.09, 1.97) after famine exposure in the first trimester of gestation. Further follow-up of the cohort is needed to provide more accurate risk estimates of mortality from specific causes of death after nutritional disturbances during gestation and very early life.

Differences in height by education among 371,105 Dutch military conscripts.

Adult height is associated with a variety of familial and socio-economic factors and large, well-defined populations are needed for a reliable assessment of their relative contributions. We therefore analyzed recorded heights from the military health examinations of 18-year conscripts in the Netherlands born between 1944 and 1947 and observed large differences by their attained education and by their father's occupation. The 5.1 cm height gradient from lowest to highest education level was more than twice as large as the gradient between father's occupation levels. The education gradient was not explained by common determinants of height including paternal occupation as a measure of familial background, region of birth, family size, or religion.

Too old to have children? Lessons from natural fertility populations.

STUDY QUESTION: Is it possible to construct an age curve denoting the ages above which women are biologically too old to reproduce? SUMMARY ANSWER: We constructed a curve based on the distribution of female age at last birth in natural fertility populations reflecting the ages above which women have become biologically too old to have children. WHAT IS KNOWN ALREADY: The median age at last birth (ALB) for females is ∼40-41 years of age across a range of natural fertility populations. This suggests that there is a fairly universal pattern of age-related fertility decline. However, little is known about the distribution of female ALB and in the present era of modern birth control, it is impossible to assess the age-specific distribution of ALB. Reliable information is lacking that could benefit couples who envisage delaying childbearing. STUDY DESIGN, SIZE, DURATION: This study is a review of high-quality historical data sets of natural fertility populations in which the distributions of female age at last birth were analysed. The studies selected used a retrospective cohort design where women were followed as they age through their reproductive years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Using a common set of eligibility criteria, large data files of natural fertility populations were prepared such that the analysis could be performed in parallel across all populations. Data on the ALB and confounding variables are presented as box and whisker plots denoting the 5th, 25th, 50th, 75th and 95th percentile distribution of the age at last birth for each population. The analysis includes the estimation of Kaplan-Meier curves for age at last birth of each population. The hazard curve for ALB was obtained by plotting the smoothed hazard curve of each population and taking the lowest hazard within a time period of at least 5 years. This lowest hazard curve was then transformed into a cumulative distribution function representing the composite curve of the end of biological fertility. This curve was based on the data from three of the six populations, having the lowest hazards of end of fertility. MAIN RESULTS AND THE ROLE OF CHANCE: We selected six natural fertility populations comprising 58 051 eligible women. While these populations represent different historical time periods, the distribution of the ages at last birth is remarkably similar. The curve denoting the end of fertility indicates that <3% of women had their last birth at age 20 years meaning that almost 98% were able to have at least one child thereafter. The cumulative curve for the end of fertility slowly increases from 4.5% at age 25 years, 7% at age 30 years, 12% at age 35 years and 20% at age 38 years. Thereafter, it rises rapidly to about 50% at age 41, almost 90% at age 45 years and approaching 100% at age 50 years. LIMITATIONS, REASONS FOR CAUTION: It may be argued that these historical fertility data do not apply to the present time; however, the age-dependent decline in fertility is similar to current populations and is consistent with the pattern seen in women treated by donor insemination. Furthermore, for reproductive ageing, we note that it is unlikely that such a conserved biological process with a high degree of heritability would have changed significantly within a century or two. WIDER IMPLICATIONS OF THE FINDINGS: We argue that the age-specific ALB curve can be used to counsel couples who envisage having children in the future. Our findings challenge the unsubstantiated pessimism regarding the possibility of natural conception after age 35 years. STUDY FUNDING/COMPETING INTEREST(S): No external funding was either sought or obtained for this study. There are no conflicts of interest to be declared.

Arts and ageing; life expectancy of historical artists in the Low Countries.

Practising arts has been linked to lowering stress, anxiety and blood pressure. These mechanisms are all known to affect the ageing process. Therefore, we examine the relation between long-term involvement in arts and life expectancy at age 50 (LE50), in a cohort of 12,159 male acoustic, literary and visual artists, who were born between 1700 and 1899 in the Low Countries. We compared the life expectancy at age 50 of the various artists with the elite and middle class of that time. In the birth cohorts before 1850, acoustic (LE50:14.5-19.5) and literary artists (LE50:17.8-20.8) had a similar life expectancy at age 50 compared to the elite (LE50:18.0-19.0). Only visual artists (LE50:15.5-17.1) had a lower life expectancy at age 50 compared to the elite at that time. For the most recent birth cohorts from 1850 through 1899, the comparison between artists and the elite reversed and acoustic and literary artist had a lower life expectancy at age 50, while visual artists enjoyed a similar life expectancy at age 50. Although artists belonged to the middle socioeconomic class and lived predominantly in urban areas with poor living conditions, they had a life expectancy similar to the elite population. This is in line with observed favourable effects of practicing arts on health in the short-term. From our historical analysis, we hypothesize several mechanisms through which artistic creativity could influence the ageing process and life expectancy. These hypotheses, however, should be formally tested before any definite conclusions on effects of arts on ageing can be drawn.

Life expectancy of artists in the Low Countries from the fifteenth to the twentieth century.

We investigated the role that urbanization and plague may have played in changes in life expectancy amongst artists in the Low Countries who were born between 1450 and 1909. Artists can be considered to be representative of a middle-class population living mostly in urban areas. The dataset was constructed using biographical information collected by the Rijksbureau voor Kunsthistorische Documentatie in The Hague, the Netherlands. As early as the beginning of the sixteenth century, life expectancy at age 20 amongst the artists had reached 40 years. After a substantial decline in the late sixteenth and the early seventeenth centuries, when plague hit the region, life expectancy at age 20 began to rise again, and this upward trend accelerated after 1850. The life expectancy of female artists commonly exceeded that of males, and sculptors had better survival prospects than painters. In comparison with elite groups in the Low Countries and elsewhere in Europe, life expectancy amongst the artists was rather high.

Historical trends in the correlation of sibling deaths in infancy in the Netherlands.

In this article, we study temporal, regional, and social variation in infant and childhood death clustering in The Netherlands, using data from three provinces. The data relate to children born in 90,000 marriages contracted between the beginning and the last quarter of the nineteenth century. Descriptive indicators show that death clustering was more frequent in the province of Zeeland and more common in the lower classes, and that it increased in two provinces over time. Shared frailty hazard models make it clear that the number of children who died before the birth of an index child had a negative effect on the mortality of index children, whereas earlier stillbirths and the number of children who died when the index child was at a young age had an increasing effect on the mortality of index children.

Marital fertility decline in the Netherlands: child mortality, real wages, and unemployment, 1860-1939.

Previous studies of the fertility decline in Europe are often limited to an earlier stage of the marital fertility decline, when the decline tended to be slower and before the large increase in earnings in the 1920s. Starting in 1860 (before the onset of the decline), this study follows marital fertility trends until 1939, when fertility reached lower levels than ever before. Using data from the Historical Sample of the Netherlands (HSN), this study shows that mortality decline, a rise in real income, and unemployment account for the decline in the Netherlands. This finding suggests that marital fertility decline was an adjustment to social and economic change, leaving little room for attitudinal change that is independent of social and economic change.