Adult offspring and their socioeconomic resources for development and survival of stroke: A Swedish and Danish nationwide register-based study.

AIMS: To explore the relationships between adult offspring's socioeconomic resources and the development of stroke and survival after stroke among older adults in Denmark and Sweden. METHODS: The study included 1,464,740 Swedes and 835,488 Danes who had turned 65 years old between 2000 and 2015. Multivariable Cox proportional hazard regression models were used to analyse incident stroke and survival after stroke until 2020. RESULTS: Lower level of offspring's education, occupation and income were associated with higher hazards of stroke among both men and women in Sweden and Denmark. Associations with offspring's education, occupation and income were most consistent for death after the acute phase and for educational level. From one to five years after stroke and compared with a high educational level of offspring, low and medium educational level were associated with 1.34 (95% confidence interval (CI): 1.11; 1.62) and 1.18 (95% CI: 1.10; 1.27) as well as 1.26 (95% CI: 1.06; 1.48) and 1.14 (1.07; 1.21) times higher hazard of death in Swedish women and men, respectively. The corresponding estimates in the Danish population were 1.36 (1.20; 1.53) and 1.10 (1.01; 1.20) for women and 1.23 (95% CI: 1.11; 1.32) and 1.13 (95% CI: 1.05; 1.21) for men. CONCLUSIONS: Adult offspring socioeconomic resources are, independently of how we measure them and of individual socioeconomic characteristics, associated with development of stroke in old age in both Denmark and Sweden. The relationships between offspring socioeconomic resources and death after stroke are present especially after the acute phase and most pronounced for educational level as a measure of offspring socioeconomic resources.

The Association of Children and Their Educational Attainment With Diabetes-related Complications and Mortality Among Older Adults With Type 2 Diabetes: A Nationwide Cohort Study.

OBJECTIVE: Socioeconomic resources and family support have been shown to improve adherence to treatment in people with type 2 diabetes (T2D) and are associated with a lower risk of diabetes-related complications and death. We investigated the associations of having children and their educational level with diabetes-related complications and death among older adults with T2D. METHODS: We included 74,588 adults who were at least 65 years of age at the time of T2D diagnosis over the period from 2000 to 2018 in Denmark and grouped them based on having children (yes [reference]/no), and their children's highest educational level (low/medium/high [reference]). Multistate models were performed with 3 states: T2D diagnosis, diabetes-related complications, and death. All models were stratified by other chronic diseases at baseline (yes/no). RESULTS: During follow-up (mean, 5.5 years), 14.6% of the adults developed a complication and 24.8% died with or without complications. Not having children was associated with a higher hazard of death without complications among adults without (hazard ratio [HR], 1.25; 95% confidence interval [CI], 1.17 to 1.33) and with (HR, 1.10; 95% CI, 1.02 to 1.18) other chronic diseases and after complications among adults without other chronic diseases (HR, 1.25; 95% CI, 1.12 to 1.38). Having children with a lower educational level was associated with a higher hazard of complications (HRlow, 1.14; 95% CI, 1.05 to 1.24; HRmedium, 1.11; 95% CI, 1.05 to 1.17), death without complications (HRlow, 1.26; 95% CI, 1.17 to 1.36; HRmedium, 1.07; 95% CI, 1.02 to 1.14), and after complications (HRlow, 1.22; 95% CI, 1.07 to 1.39) among adults without other chronic diseases. CONCLUSIONS: Among adults without other chronic diseases, having no children or having children with lower educational levels was associated with a higher hazard of death. Among these adults, having children with lower educational levels was also associated with a higher hazard of diabetes-related complications.

Underlying pathways of social inequality in tooth loss: the mediating role of sugary beverages and diabetes.

BACKGROUND: Previous studies show social inequality in tooth loss, but the underlying pathways are not well understood. The aim was to investigate the mediated proportion of sugary beverages (SBs) and diabetes and the association between educational level and tooth loss, and to investigate whether the indirect effect of SBs and diabetes varied between educational groups in relation to tooth loss. METHODS: Data from 47,109 Danish men and women aged 50 years or older included in the Danish Diet, Cancer and Health Study was combined with data from Danish registers. Using natural effect models, SBs and diabetes were considered as mediators, and tooth loss was defined as having <15 teeth present. RESULTS: In total, 10,648 participants had tooth loss. The analyses showed that 3% (95% confidence interval 2-4%) of the social inequality in tooth loss was mediated through SBs and diabetes. The mediated proportion was mainly due to differential exposure to SBs and diabetes among lower educational groups. CONCLUSIONS: The findings show that SBs and diabetes to a minor degree contribute to tooth-loss inequalities. The explanation indicates that individuals in lower educational groups have higher consumption of SBs and more often suffer from diabetes than higher educational groups.

Healthcare resource utilization in patients with treatment-resistant depression-A Danish national registry study.

OBJECTIVES: To investigate healthcare resource utilization (HRU) and associated costs by depression severity and year of diagnosis among patients with treatment-resistant depression (TRD) in Denmark. METHODS: Including all adult patients with a first-time hospital contact for major depressive disorder (MDD) in 1996-2015, TRD patients were defined at the second shift in depression treatment (antidepressant medicine or electroconvulsive therapy) and matched 1:2 with non-TRD patients. The risk of utilization and amount of HRU and associated costs including medicine expenses 12 months after the TRD-defining date were reported, comparing TRD patients with non-TRD MDD patients. RESULTS: Identifying 25,321 TRD-patients matched with 50,638 non-TRD patients, the risk of psychiatric hospitalization following TRD diagnosis was 138.4% (95%-confidence interval: 128.3-149.0) higher for TRD patients than for non-TRD MDD patients. The number of hospital bed days and emergency department (ED) visits were also higher among TRD patients, with no significant difference for somatic HRU. Among patients who incurred healthcare costs, the associated HRU costs for TRD patients were 101.9% (97.5-106.4) higher overall, and 55.2% (50.9-59.6) higher for psychiatric services than those of non-TRD patients. The relative differences in costs for TRD-patients vs non-TRD patients were greater for patients with mild depression and tended to increase over the study period (1996-2015), particularly for acute hospitalizations and ED visits. LIMITATIONS: TRD was defined by prescription patterns besides ECT treatments. CONCLUSION: TRD was associated with increased psychiatric-related HRU. Particularly the difference in acute hospitalizations and ED visits between TRD and non-TRD patients increased over the study period.

Adverse SARS-CoV-2-associated outcomes among people experiencing social marginalisation and psychiatric vulnerability: A population-based cohort study among 4,4 million people.

Background: Knowledge of the adverse problems related to SARS-CoV-2 infection in marginalised and deprived groups may help to prioritise more preventive efforts in these groups. We examined adverse outcomes associated with SARS-CoV-2 infection among vulnerable segments of society. Methods: Using health and administrative registers, a population-based cohort study of 4.4 million Danes aged at least 15 years from 27 February 2020 to 15 October 2021 was performed. People with 1) low educational level, 2) homelessness, 3) imprisonment, 4) substance abuse, 5) supported psychiatric housing, 6) psychiatric admission, and 7) severe mental illness were main exposure groups. Chronic medical conditions were included for comparison. COVID-19-related outcomes were: 1) hospitalisation, 2) intensive care, 3) 60-day mortality, and 4) overall mortality. PCR-confirmed SARS-CoV-2 infection and PCR-testing were also studied. Poisson regression analysis was used to compute adjusted incidence and mortality rate ratios (IRRs, MRRs). Findings: Using health and administrative registers, we performed a population-based cohort study of 4,412,382 individuals (mean age 48 years; 51% females). In all, 257,450 (5·8%) individuals had a PCR-confirmed SARS-CoV-2 infection. After adjustment for age, calendar time, and sex, we found that especially people experiencing homelessness had high risk of hospitalisation (IRR 4·36, 95% CI, 3·09-6·14), intensive care (IRR 3·12, 95% CI 1·29-7·52), and death (MRR 8·17, 95% CI, 3·66-18·25) compared with people without such experiences, but increased risk was found for all studied groups. Furthermore, after full adjustment, including for status of vaccination against SARS-CoV-2 infection, individuals with experiences of homelessness and a PCR-confirmed SARS-CoV-2 infection had 41-times (95% CI, 24·84-68·44) higher risk of all-cause death during the study period compared with individuals without. Supported psychiatric housing was linked to almost 3-times higher risk of hospitalisation and 60-day mortality following SARS-CoV-2 infection compared with the general population with other living circumstances. Interpretation: Socially marginalised and psychiatrically vulnerable individuals had substantially elevated risks of adverse health outcomes following SARS-CoV-2 infection. The results highlight that pandemic preparedness should address inequalities in health, including infection prevention and vaccination of vulnerable groups. Funding: Novo Nordisk Foundation.

Socioeconomic Position and Late-Onset Dementia: A Nationwide Register-Based Study.

OBJECTIVES: Previous research on the association between socioeconomic position (SEP) and dementia has not sufficiently accounted for the complex relationship between education and occupation. We investigated the independent and joint effects of educational attainment and occupation-based SEP on dementia. METHODS: We used register-based information about educational attainment, occupation-based SEP, and dementia from 1,210,720 individuals. Information about cognitive ability at conscription was available for a subsample of men. RESULTS: When mutually adjusted, lower educational attainment and occupation-based SEP were associated with higher dementia risk in a dose-response manner. Higher occupation-based SEP partly mitigated the higher dementia risk associated with lower educational attainment. After adjusting for cognitive ability in a subgroup of men, only unskilled work was associated with higher dementia risk. DISCUSSION: Occupation-based SEP is independently associated with dementia and may mitigate the higher dementia risk associated with short education. Future research should elucidate the mechanisms underlying social inequality in dementia.

Data-Driven Model Building for Life-Course Epidemiology.

Life-course epidemiology is useful for describing and analyzing complex etiological mechanisms for disease development, but existing statistical methods are essentially confirmatory, because they rely on a priori model specification. This limits the scope of causal inquiries that can be made, because these methods are suited mostly to examine well-known hypotheses that do not question our established view of health, which could lead to confirmation bias. We propose an exploratory alternative. Instead of specifying a life-course model prior to data analysis, our method infers the life-course model directly from the data. Our proposed method extends the well-known Peter-Clark (PC) algorithm (named after its authors) for causal discovery, and it facilitates including temporal information for inferring a model from observational data. The extended algorithm is called temporal PC. The obtained life-course model can afterward be perused for interesting causal hypotheses. Our method complements classical confirmatory methods and guides researchers in expanding their models in new directions. We showcase the method using a data set encompassing almost 3,000 Danish men followed from birth until age 65 years. Using this data set, we inferred life-course models for the role of socioeconomic and health-related factors on development of depression.

Are Advances in Survival Among the Oldest Old Seen Across the Spectrum of Health and Functioning?

BACKGROUND: Mortality rates have been reduced by half over the last 60 years for nonagenarians, and the progress is continuing. The greater survival might be due to overtreatment of severely physically and cognitively disabled individuals, which is a big concern for societies and individuals. METHODS: The study population comprised two Danish birth cohorts: the 1905 Cohort and the 1915 Cohort. At age 95, all from the two cohorts who were still alive and living in Denmark were invited to participate in a health survey that used the same assessment instrument. A total of 2,670 (56.8%) persons participated in the two surveys and survival was assessed through a 7.3-year follow-up period during which 2,497 (93.5%) had died, and with virtually no loss to follow-up. RESULTS: Despite the increasing chance of surviving to age 95, the 1915 Cohort had significantly better health and functioning than the 1905 Cohort. The survival advantage in the 1915 Cohort continued in the follow-up period after age 95: Median survival length was 2.4 months longer, p = .011. This advantage was not statistically associated with different levels of activities of daily living, physical performance, cognitive functioning, self-rated health and life satisfaction. However, the advantage tended to be more pronounced among people with better health. CONCLUSIONS: Life span and health increases among the oldest old. The improvement in survival for 95-year olds born in 1915 compared with 1905 was seen across the whole spectrum of health and functioning, with a tendency towards bigger improvement among those in good health.

Chronic Diseases in High-Cost Users of Hospital, Primary Care, and Prescription Medication in the Capital Region of Denmark.

BACKGROUND: A small proportion of patients account for the majority of health care costs. This group is often referred to as high-cost users (HCU). A frequently described characteristic of HCU is chronic disease. Yet, there is a gap in understanding the economic burden of chronic diseases associated with HCU to different types of health care services. OBJECTIVE: To analyze which frequent chronic diseases have the strongest association with HCU overall, and HCU in hospital, primary care, and prescription medication. DESIGN: This is a register-based observational study on Danish health service costs for various diseases in different medical settings. PARTICIPANTS: A total of 1,350,677 individuals aged ≥ 18 years living in the Capital Region of Denmark by 1 January 2012 were included. MAIN MEASURES: Chronic diseases, costs, and sociodemographic data were extracted from the nationwide registers, including data from hospitals, primary care, and medicine consumption. These information were merged on an individual level. KEY RESULTS: Cancer, mental disorders except depression, and heart diseases have the strongest association with HCU overall. Mental disorders except depression were in the three diseases most prevalent in HCU in all the three health care services. CONCLUSIONS: Our results show that the chronic diseases that have the strongest association with HCU differ between different types of health care services. Our findings may be helpful in informing future policies about health care organization and may guide to different prevention, treatment, and rehabilitation strategies that could lessen the burden in the hospital.

Socioeconomic Position Across the Life Course and Cognitive Ability Later in Life: The Importance of Considering Early Cognitive Ability.

Objective: Investigate direct and indirect associations between markers of socioeconomic position (SEP) across the life course and midlife cognitive ability while addressing methodological limitations in prior work. Method: Longitudinal data from the Danish Metropolit cohort of men born in 1953 (N = 2,479) who completed ability tests at age 12, 18, and 56-58 linked to register-based information on paternal occupational class, educational attainment, and occupational level. Associations were assessed using structural equation models, and different models were estimated to examine the importance of accounting for childhood ability and measurement error. Results: Associations between adult SEP measures and midlife ability decreased significantly when adjusting for childhood ability and measurement error. The association between childhood and midlife ability was by far the strongest. Discussion: The impact of adult SEP on later life ability may be exaggerated when not accounting for the stability of individual differences in cognitive ability and measurement error in test scores.

Childhood socioeconomic position and physical capability in late-middle age in two birth cohorts from the Copenhagen aging and midlife biobank.

This study examines the association between childhood socioeconomic position and objective physical capability including new functional measures of potential relevance to a population in late-middle age. The study population covers two Danish birth cohorts followed-up in the Copenhagen Aging and Midlife Biobank (age 48-58 years, 2009-2011, N = 4,204). Results from linear regression models revealed that being born in higher socioeconomic position was associated with higher jump height: Paternal occupational class four = 0.19 cm (95% confidence interval (CI): -0.44, 0.82), three = 0.59 cm (95% CI: -0.02, 1.19), two = 1.29 cm (95% CI: 0.64, 1.94), and one = 1.29 cm (95% CI: 0.45, 2.13) (reference = five); medium parental social class = 0.88 cm (95% CI: 0.03, 1.72) and high = 1.79 cm (95% CI: 0.94, 2.63) (reference = low). Higher childhood socioeconomic position was also associated with better chair rise performance and hand grip strength, while among women it was related to reduced flexibility: Medium parental social class = -1.31 cm (95% CI: -3.05, 0.42) and high = -2.20 cm (95% CI: -3.94, -0.47) (reference = low); unwed mother = 1.75 cm (95% CI: 0.36, 3.14) (reference = married). Overall, the findings suggest that higher childhood socioeconomic position is primarily related to moderately better scores in the most strenuous physical capability measures and hand grip strength among healthy adults in late-middle age.

Universal infant health interventions and young adult outcomes.

Three recent studies have documented short- and long-run benefits of early-infancy health interventions in Norway, Sweden, and Denmark: Universal nurse home visiting (NHV) and well-baby center care decreased infant mortality and positively impacted long-run survival (DK, S), morbidity (DK, N), and educational and labor market outcomes (N). Using Danish conscription data, this paper examines intermediate outcomes to assess both potential mechanisms and the importance of selective survival for the long-run health effects of NHV. We do not find strong effects of NHV for young adult's height or obesity status, but we find that NHV increases treated individuals' probability of emigration. As emigrants in our sample are positively selected and as they are not part of the samples used in long-run analyses, this finding suggests that the established long-run health benefits of NHV may be lower bounds.

Educational inequality in cardiovascular diseases: a sibling approach.

AIMS: Educational inequality in diseases in the circulatory system (here termed cardiovascular disease) is well documented but may be confounded by early life factors. The aim of this observational study was to examine whether the associations between education and all cardiovascular diseases, ischaemic heart disease and stroke, respectively, were explained by family factors shared by siblings. METHODS: The study population included all individuals born in Denmark between 1950 and 1979 who had at least one full sibling born in the same period. Using Cox regression, data were analysed in conventional cohort and within-sibship analyses in which the association was examined within siblings discordant on education. Assuming that attenuation of associations in the within-sibship as compared with the cohort analyses would indicate confounding from factors shared within families. RESULTS: A lower educational status was associated with a higher risk of cardiovascular disease, ischaemic heart disease and stroke. All associations attenuated in the within-sibship analyses, in particular in the analyses on ischaemic heart disease before age 45 years. For instance, in the cohort analyses, the hazard rate of ischaemic heart disease among women less than 45 years who had a primary school education was 94% (hazard ratio 1.94 (1.78-2.12) higher than among those with a vocational education, while it attenuated to 51% (hazard ratio 1.51 (1.34-1.71)) in the within-sibship analysis. CONCLUSIONS: Confounding from factors shared by siblings explained the associations between education and the cardiovascular disease outcomes but to varying degrees. This should be taken into account when planning interventions aimed at reducing educational inequalities in the development of cardiovascular disease, ischaemic heart disease and stroke.

[Benzodiazepines still play a role in modern psychiatric therapy].

Benzodiazepines (BZ) are widely used for anxiety across psychiatric diagnoses, but for the last decades regulation has been increasingly tight due to problems with tolerance, addiction, withdrawal symptoms and cognitive side effects. Some guidelines claim that BZ only work for a few weeks, and that BZ cause traffic accidents, increased mortality and dementia. In Denmark, the use of BZ has been substantially reduced. In this article it is argued, that not all patients habituate, that most of the epidemiological findings are hampered by confounding, and that there still is a role for long-term use of BZ in the treatment of anxiety.

Survival Prognosis in Very Old Adults.

OBJECTIVES: To determine whether simple functional indicators are predictors of survival prognosis in very old adults. DESIGN: In-person survey conducted over a 3-month period in 1998; assessment of survival over a 15-year follow-up period. SETTING: Denmark. PARTICIPANTS: All 3,600 Danes born in 1905 and living in Denmark in 1998, were invited to participate regardless of residence and health; 2,262 (63%) participated in the survey: 1,814 (80.2%) in person and 448 (19.8%) through a proxy. MEASUREMENTS: Socioeconomic factors, medications and diseases, activities of daily living, physical performance, cognition, depression symptomatology, self-rated health, and all-cause mortality, evaluated as average remaining lifespan and chance of surviving to 100 years. RESULTS: Men aged 92 to 93 had an overall 6.0% chance of surviving to 100 years, whereas the chance for women was 11.4%. Being able to rise without use of hands increased the chance for men to 11.2% (95% confidence interval (CI)=7.7-14.7) and for women to 22.0% (95% CI=18.9-25.1). When combining this with a Mini-Mental State Examination (MMSE) scores from 28 to 30, the chances were 21.7% (95% CI=11.5-31.9) for men and 34.2% (95% CI=24.8-43.5) for women. CONCLUSION: Chair stand score combined with MMSE score is a quick and easy way to estimate overall chance of survival in very old adults, which is particularly relevant when treatment with potential side effects for nonacute diseases is considered.

Socio-economic position and time trends in invasive management and case fatality after acute myocardial infarction in Denmark.

BACKGROUND: Lower case fatality and increased use of evidence-based invasive management incl. coronary angiography (CAG) have been reported for patients admitted with acute myocardial infarction (AMI) in the last 25 years. This article seeks to investigate whether these advances have benefitted patients in all socio-economic groups and how this has impacted on inequality in case fatality. METHODS: Forty three thousand eight hundred and forty three patients admitted with AMI in the period from 2001 to 2009 were included. Socio-economic position was measured using individual information on education. Age-standardized cumulative incidence of CAG within 1, 3 and 30 days along with age-standardized case fatality within 30 and 365 days were estimated. Cox regression models were used to model the relative inequality over time. RESULTS: Use of CAG within 1, 3 and 30 days increased for all educational groups over time and the inequality in CAG within 1 and 3 days seen in the beginning of the time frame was eliminated. Case fatality decreased in all educational groups and the relative inequality in 30 days case fatality decreased for women but not 365 days case fatality. No change was seen for inequality in case fatality for men. CONCLUSION: Increased use of CAG within the evidence based time frame was observed along with a decrease in inequality. However, a reduction in inequality was only observed for short term case fatality, and only for women. These results suggest that inequality in case fatality is not primarily driven by inequality in invasive management of AMI.

Does access to invasive examination and treatment influence socioeconomic differences in case fatality for patients admitted for the first time with non-ST-elevation myocardial infarction or unstable angina?

AIMS: Our aim was to investigate whether there is social inequality in access to invasive examination and treatment, and whether access explains social inequality in case fatality in a nationwide sample of patients admitted for the first time with unstable angina or non-ST-elevation myocardial infarction (NSTEMI) in Denmark. METHODS AND RESULTS: All patients admitted for the first time with NSTEMI (n=16,625) or unstable angina (n=8,800) from 2001 to 2009 in Denmark were included. We measured time from admission to coronary angiography (CAG), percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The outcomes were 30-day and one-year case fatality. We found social inequality in access to CAG and one-year case fatality for both NSTEMI and unstable angina patients, but the time waited for CAG did not explain the social inequality in case fatality. CONCLUSIONS: Despite nominal equal access to health care, social inequality in case fatality after NSTEMI and unstable angina exists in Denmark. The patients with the shortest education waited longer for angio-graphy; however, this did not seem to explain inequality in case fatality. This register-based study was approved by the Danish Data Protection Agency (Approval number 2010-41-5263). Register-based studies do not need approval by a medical ethics committee in Denmark.

Is Intelligence in Early Adulthood Associated With Midlife Physical Performance Among Danish Males?

OBJECTIVE: Insights into the causes of variances in physical performance are important to prevent mobility limitations in old age. We examined associations between intelligence in early adulthood and midlife physical performance. METHOD: Data from the Copenhagen Aging and Midlife Biobank were analyzed using linear regression. In total, 2,848 male cohort members had intelligence scores from conscription and physical performance measures from midlife. RESULTS: In adjusted models, a 1 SD increase in intelligence resulted in 1.10 more chair-rises (p < .001), a 1.03 cm higher jump (p < .001), a 3.69% smaller balance area (p < .001), a 0.71 kg increase in handgrip strength (p < .001), and a 5.03 N increase in back force (p < .001). Results for flexibility and abdominal force were not significant. DISCUSSION: Public health interventions should focus on addressing people with different cognitive abilities and bear in mind that prevention of mobility limitations might need to start early in life.

Lifetime socio-economic position and depression: an analysis of the influence of cognitive function, behaviour and inflammatory markers.

BACKGROUND: Little is known about the influence of lifetime socio-economic position (SEP) on adult depression. We examined the association of SEP during the life course with depressive mood in late midlife and explored whether cognitive function at age 20, health-related behaviour and inflammatory biomarkers explained any associations. METHODS: A cohort of 2482 Danish men born in 1953 with information from birth, and conscript board examinations was followed-up with assessment of depressive mood and blood sampling in 2010. Simple and multiple linear regression were used to investigate associations among variables. RESULTS: Social circumstances during the life course were associated with depressive mood. Further, low lifetime SEP was associated with lower cognitive score, smoking, alcohol use, high body mass index (BMI) and increased level of high sensitive ProReactive Protein and Interleukin-6. These covariables were also associated with depressive mood and when they were included into the regression model together with life time SEP, the ß-estimates for the latter attenuated, when smoking, alcohol and BMI were entered, while the inclusion of cognitive function and the inflammatory biomarkers had limited effect on the relation between lifetime SEP and depressive mood. CONCLUSIONS: Lifetime SEP was associated with depressive mood and health-related behaviour explained a part of the relation.

Exploring educational disparities in risk of preterm delivery: a comparative study of 12 European birth cohorts.

BACKGROUND: An association between education and preterm delivery has been observed in populations across Europe, but differences in methodology limit comparability. We performed a direct cross-cohort comparison of educational disparities in preterm delivery based on individual-level birth cohort data. METHODS: The study included data from 12 European cohorts from Denmark, England, France, Lithuania, the Netherlands, Norway, Italy, Portugal, and Spain. The cohorts included between 2434 and 99 655 pregnancies. The association between maternal education and preterm delivery (22-36 completed weeks of gestation) was reported as risk ratios, risk differences, and slope indexes of inequality with 95% confidence intervals (CIs). RESULTS: Singleton preterm live delivery proportion varied between 3.7% and 7.5%. There were large variations between the cohorts in the distribution of education and maternal characteristics. Nevertheless, there were similar educational differences in risk of preterm delivery in 8 of the 12 cohorts with slope index of inequality varying between 2.2 [95% CI 1.1, 3.3] and 4.0 [95% CI 1.4, 6.6] excess preterm deliveries per 100 singleton deliveries among the educationally most disadvantaged, and risk ratio between the lowest and highest education category varying from 1.4 [95% CI 1.1, 1.8] to 1.9 [95% CI 1.2, 3.1]. No associations were found in the last four cohorts. CONCLUSIONS: Educational disparities in preterm delivery were found all over Europe. Despite differences in the distributions of education and preterm delivery, the results were remarkably similar across the cohorts. For those few cohorts that did not follow the pattern, study and country characteristics did not explain the differences.