Social inequality in prevalence of NCD risk factors: a cross-sectional analysis from the population-based Tromsø Study 2015-2016.

OBJECTIVE: We aimed to examine associations between educational level, serving as an indicator of socioeconomic position, and prevalence of WHO-established leading behavioural and biological risk factors for non-communicable diseases (NCDs), in middle-aged to older women and men. DESIGN: Population-based cross-sectional study. SETTING: All inhabitants of the municipality of Tromsø, Norway, aged ≥40 years, were invited to the seventh survey (2015-2016) of the Tromsø Study; an ongoing population-based cohort study. PARTICIPANTS: Of the 32 591 invited; 65% attended, and a total of 21 069 women (53%) and men aged 40-99 years were included in our study. OUTCOME MEASURES: We assessed associations between educational level and NCD behavioural and biological risk factors: daily smoking, physical inactivity (sedentary in leisure time), insufficient fruit/vegetable intake (<5 units/day), harmful alcohol use (>10 g/day in women, >20 g/day in men), hypertension, obesity, intermediate hyperglycaemia and hypercholesterolaemia. These were expressed as odds ratios (OR) per unit decrease in educational level, with 95% CIs, in women and men. RESULTS: In women (results were not significantly different in men), we observed statistically significant associations between lower educational levels and higher odds of daily smoking (OR 1.69; 95% CI 1.60 to 1.78), physical inactivity (OR 1.38; 95% CI 1.31 to 1.46), insufficient fruit/vegetable intake (OR 1.54, 95% CI 1.43 to 1.66), hypertension (OR 1.25; 95% CI 1.20 to 1.30), obesity (OR 1.23; 95% CI 1.18 to 1.29), intermediate hyperglycaemia (OR 1.12; 95% CI 1.06 to 1.19), and hypercholesterolaemia (OR 1.07; 95% CI 1.03 to 1.12), and lower odds of harmful alcohol use (OR 0.75; 95% CI 0.72 to 0.78). CONCLUSION: We found statistically significant educational gradients in women and men for all WHO-established leading NCD risk factors within a Nordic middle-aged to older general population. The prevalence of all risk factors increased at lower educational levels, except for harmful alcohol use, which increased at higher educational levels.

National health registries - a 'goldmine' for studying non-communicable disease occurrence in Norway - the NCDNOR project.

To estimate occurrence of non-communicable diseases (NCDs) over the life-course in the Norwegian population, national health registries are a vital source of information since they fully represent the entire non-institutionalised population. However, as they are mainly established for administrative purposes, more knowledge about how NCDs are recorded in the registries is needed. To establish this, we begin by counting the number of individuals registered annually with one or more NCDs in any of the registries. The study population includes all inhabitants who lived in Norway from 2004 to 2020 (N~6.4m). The NCD outcomes are diabetes, cardiovascular diseases, chronic obstructive lung diseases, cancer and mental disorders/substance use disorders. Further, we included hip fractures in our NCD concept. The data sources used to identify individuals with NCDs, including detailed information on diagnoses in primary and secondary health care and dispensings of prescription drugs, are the Cancer Registry of Norway, The Norwegian Patient Registry, The Norwegian Control and Payment of Health Reimbursement database, and The Norwegian Prescription Database. The number of individuals registered annually with an NCD diagnosis and/or a dispensed NCD drug increased over the study period. Changes over time may reflect changes in disease incidence and prevalence, but also changes in disease-specific guidelines, reimbursement schemes and access to and use of health services. Data from more than one health registry to identify individuals with NCDs are needed since the registries reflect different levels of health care services and therefore may reflect disease severity.

Clustering and trajectories of key noncommunicable disease risk factors in Norway: the NCDNOR project.

Noncommunicable diseases (NCDs) are a leading cause of premature death globally and have common preventable risk factors. In Norway, the NCDNOR-project aims at establishing new knowledge in the prevention of NCDs by combining information from national registries with data from population-based health studies. In the present study, we aimed to harmonize data on key NCD risk factors from the health studies, describe clustering of risk factors using intersection diagrams and latent class analysis, and identify long-term risk factor trajectories using latent class mixed models. The harmonized study sample consisted of 808,732 individuals (1,197,158 participations). Two-thirds were exposed to ≥ 1 NCD risk factor (daily smoking, physical inactivity, obesity, hypertension, hypercholesterolaemia or hypertriglyceridaemia). In individuals exposed to ≥ 2 risk factors (24%), we identified five distinct clusters, all characterized by fewer years of education and lower income compared to individuals exposed to < 2 risk factors. We identified distinct long-term trajectories of smoking intensity, leisure-time physical activity, body mass index, blood pressure, and blood lipids. Individuals in the trajectories tended to differ across sex, education, and body mass index. This provides important insights into the mechanisms by which NCD risk factors can occur and may help the development of interventions aimed at preventing NCDs.

Achievements of primary prevention targets in individuals with high risk of cardiovascular disease: an 8-year follow-up of the Tromsø study.

Aims: To study change over 8 years in cardiovascular risk, achievement of national guideline-based treatment targets of lipids, blood pressure (BP) and smoking in primary prevention of cardiovascular disease (CVD), medication use, and characteristics associated with target achievement among individuals with high CVD risk in a general population. Methods and results: We followed 2524 women and men aged 40-79 years with high risk of CVD attending the population-based Tromsø study in 2007-08 (Tromsø6) to their participation in the next survey in 2015-16 (Tromsø7). We used descriptive statistics and regression models to study change in CVD risk and medication use, and characteristics associated with treatment target achievement. In total, 71.4% reported use of BP- and/or lipid-lowering medication at second screening. Overall, CVD risk decreased during follow-up, with a larger decrease among medication users compared with non-users. Treatment target achievement was 31.0% for total cholesterol <5 mmol/L, 27.3% for LDL cholesterol <3 mmol/L, 43.4% for BP <140/90 (<135/85 if diabetes) mmHg, and 85.4% for non-smoking. A total of 9.8% reached all treatment targets combined. Baseline risk factor levels and current medication use had the strongest associations with treatment target achievement. Conclusion: We found an overall improvement in CVD risk factors among high-risk individuals over 8 years. However, guideline-based treatment target achievement was relatively low for all risk factors except smoking. Medication use was the strongest characteristic associated with achieving treatment targets. This study has demonstrated that primary prevention of CVD continues to remain a major challenge.

Impact of Blood Pressure in the Early 40s on Left Atrial Volumes in the Mid-60s: Data From the ACE 1950 Study.

Background Echocardiographic measures of left atrial volumes are powerful predictors of cardiovascular events and important for assessing diastolic dysfunction. Despite this, there is limited knowledge of factors influencing left atrial remodeling. In particular, the impact of blood pressure in those in their early 40s on left atrial volumes later in life has not been sufficiently elucidated. Methods and Results We linked data from individuals born in 1950 who participated in the Age 40 Program, and the ACE (Akershus Cardiac Examination) 1950 Study. We divided the study population into quartiles of systolic blood pressure in their early 40s and assessed the proportion of individuals with an enlarged left atrium in their mid-60s. The associations between blood pressure and left atrial volumes were assessed in linear regression analyses. Of the 2591 individuals included in this study, 1302 (50.3%) were women, and the mean age in the Age 40 Program was 40.1±0.3 years. Systolic blood pressure was 128.1±13.6 mm Hg and diastolic blood pressure was 78.3±9.5 mm Hg. Mean age in the ACE 1950 Study was 64.0±0.6 years. The proportion of individuals with an enlarged left atrium increased across the quartiles of systolic blood pressure (P=0.001). Systolic blood pressure was independently associated with left atrial volumes; the end-systolic volume was 0.09 mL (95% CI, 0.04-0.14 mL) larger per 1-mm Hg higher systolic blood pressure. Conclusions Our findings suggest that increased blood pressure in those in their early 40s is relevant for left atrial remodeling later in life. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01555411.

Treatable Traits in Misdiagnosed Chronic Obstructive Pulmonary Disease: Data from the Akershus Cardiac Examination 1950 Study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is often misdiagnosed. We aimed to estimate the prevalence of misdiagnosed COPD in middle-aged Norwegians, and to assess potentially treatable clinical traits in over- and undiagnosed individuals. METHODS AND FINDINGS: The Akershus Cardiac Examination (ACE) 1950 Study is a population-based study of the 1950 birth cohort of Akershus county including 3706 participants aged 62-65 years at baseline. COPD was defined as a forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) ratio < lower limit of normal (LLN). Misdiagnosed COPD was defined according to self-reported COPD. A total of 259 (7.1%) participants had spirometry confirmed COPD. Of these, only 72 (28%) reported having COPD, thus 187 (72%) were undiagnosed. A total of 92 (2.5%) of the 164 particpants who reported having COPD had an FEV1/FVC ratio ≥ LLN and were overdiagnosed. They had lower lung function, and more respiratory symptoms, self-reported asthma, eosinophils, and sleep apnea than other non-COPD participants . The main predictor of being overdiagnosed was overweight. Spirometry in participants reporting wheezing or cough and current smokers or participants with ≥20 tobacco pack-year history would have identified 85% of the undiagnosed cases. CONCLUSION: Both over- and underdiagnosis of COPD is frequent. Undiagnosed individuals have better lung function and less symptoms, but similar prevalence of comorbidities and systemic inflammation. Overdiagnosed individuals have treatable traits including asthma, eosinophilic inflammation, and sleep apnea. The main predictor of being overdiagnosed was being overweight.

Occupational physical activity and longevity in working men and women in Norway: a prospective cohort study.

BACKGROUND: Studies suggest that high occupational physical activity increases mortality risk. However, it is unclear whether this association is causal or can be explained by a complex network of socioeconomic and behavioural factors. We aimed to examine the association between occupational physical activity and longevity, taking a complex network of confounding variables into account. METHODS: In this prospective cohort study, we linked data from Norwegian population-based health examination surveys, covering all parts of Norway with data from the National Population and Housing Censuses and the Norwegian Cause of Death Registry. 437 378 participants (aged 18-65 years; 48·7% men) self-reported occupational physical activity (mutually exclusive groups: sedentary, walking, walking and lifting, and heavy labour) and were followed up from study entry (between February, 1974, and November, 2002) to death or end of follow-up on Dec 31, 2018, whichever came first. We estimated differences in survival time (death from all causes, cardiovascular disease, and cancer) between occupational physical activity categories using flexible parametric survival models adjusted for confounding factors. FINDINGS: During a median of 28 years (IQR 25-31) from study entry to the end of follow-up, 74 203 (17·0%) of the participants died (all-cause mortality), of which 20 111 (27·1%) of the deaths were due to cardiovascular disease and 29 886 (40·3%) were due to cancer. Crude modelling indicated shorter mean survival times among men in physically active occupations than in those with sedentary occupations. However, this finding was reversed following adjustment for confounding factors (birth cohort, education, income, ethnicity, prevalent cardiovascular disease, smoking, leisure-time physical activity, body-mass index), with estimates suggesting that men in occupations characterised by walking, walking and lifting, and heavy labour had life expectancies equivalent to 0·4 (95% CI -0·1 to 1·0), 0·8 (0·3 to 1·3), and 1·7 (1·2 to 2·3) years longer, respectively, than men in the sedentary referent category. Results for mortality from cardiovascular disease and cancer showed a similar pattern. No clear differences in survival times were observed between occupational physical activity groups in women. INTERPRETATION: Our results suggest that moderate to high occupational physical activity contributes to longevity in men. However, occupational physical activity does not seem to affect longevity in women. These results might inform future physical activity guidelines for public health. FUNDING: The Norwegian Research Council (grant number 249932/F20).

Underlying conditions in adults with COVID-19. / Underliggende tilstander hos voksne med covid-19.

BACKGROUND: Cardiovascular diseases, cancer, type-2 diabetes and chronic obstructive pulmonary disease (COPD) were initially noted as the most common diseases among individuals who were hospitalised for COVID-19. However, the evidence base is weak. The objective of this study is to describe how selected diseases were distributed among adults with confirmed COVID-19 (COVID-19 positive tests) and among those hospitalised for COVID-19 compared to the general population. MATERIAL AND METHOD: We used data from the Norwegian Patient Registry, the Norwegian Registry for Primary Health Care and the Norwegian Surveillance System for Communicable Diseases for adults from the age of 20 and older for the period 1 March 2020-13 May 2020. RESULTS: Of all those who tested positive for COVID-19, 7 632 (94 %) were aged 20 years or older, and 1 025 (13.4 %) of these had been hospitalised. Among those hospitalised with COVID-19, there was a higher proportion of individuals with cardiovascular diseases (18.3 % versus 15.6 %), cancer (6.9 % versus 5.4 %), type-2 diabetes (8.6 % versus 5.2 %) and COPD (3.8 % versus 2.7 %) than in the general population as a whole after adjusting for age. The proportion of hospitalised patients with asthma, other chronic respiratory disease, cardiovascular disease, ongoing cancer treatment, complications related to hypertension, obesity and overweight, neurological disorders and cardiac and renal failure was also higher than in the general population. There were few differences between persons who had tested positive for COVID-19 and the general population in terms of underlying conditions. INTERPRETATION: Among those hospitalised for COVID-19, there was a higher proportion of patients with underlying illnesses than in the general population. This may indicate that these patients tend to have a more severe course of disease or that they are more likely to be hospitalised compared to healthy individuals. The results must be interpreted with caution, since the sample of COVID-19 individuals is non-random.

Is the Disease Burden from COPD in Norway Falling off? A Study of Time Trends in Three Different Data Sources.

Background: Less smoking should lead to fewer COPD cases. We aimed at estimating time trends in the prevalence and burden of COPD in Norway from 2001 to 2017. Methods: We used pre-bronchodilator spirometry and other health data from persons aged 40-84 years in three surveys of the Tromsø Study, 2001-2002, 2007-2008 and 2015-2016. We applied spirometry lower limits of normal (LLN) according to Global Lung Initiative 2012. Age-standardized prevalence was determined. We defined COPD as FEV1/FVC

Early adulthood weight, subsequent midlife weight change and risk of cardiovascular disease mortality: an analysis of Norwegian cardiovascular surveys.

BACKGROUND: The time between early adulthood and midlife is important for obesity development. There is paucity of studies using objectively measured body mass index (BMI) at both time points with full range of midlife cardiovascular risk factors. We aimed to investigate the risk of cardiovascular disease (CVD) mortality associated with different levels of objectively measured change in body weight from early adulthood to midlife, and to assess whether risk is primarily explained by midlife cardiovascular risk factors. METHODS: Pooled data from Norwegian health surveys (1985-2003), Tuberculosis screenings, Conscript data and the Norwegian Educational database were linked to the Cause of Death Registry. Health survey participants with data on objectively measured weight and height in both early adulthood (18-20 years) and midlife (40-50 years) were included, n = 148,021. Cox regression models were used to assess associations between weight change and CVD mortality. RESULTS: Total analysis time included 2,841,174 person years. Mean follow-up was 19 (standard deviation 4) years. Participants being normal weight in early adulthood and obese in midlife had a hazard ratio (HR) of CVD mortality of 2.09 (95% CI 1.74-2.50) relative to those who were normal weight at both times. The corresponding HR of those being obese at both times was 5.15 (3.61-7.36). Adjustment for CVD risk factors attenuated these associations. Gaining ≥15 kg between early adulthood and midlife was associated with higher CVD mortality after adjustment for early adulthood weight (HR 1.51 (1.20-1.89)), and for smoking and education (HR 1.63 (1.30-2.04)), however not after adjustment for mediating CVD risk factors. CONCLUSIONS: Obesity both in early adulthood and in midlife was associated with CVD mortality. Weight gain of ≥15 kg from early adulthood to midlife was also associated with CVD mortality, but not after adjustment for mediating CVD risk factors.

Associations of tobacco smoking with body mass distribution; a population-based study of 65,875 men and women in midlife.

BACKGROUND: Studies indicate an effect of smoking toward abdominal obesity, but few assess hip and waist circumferences (HC and WC) independently. The present study aimed to assess the associations of smoking status and volume smoked with HC and WC and their ratio in a population with low prevalence of obesity together with high prevalence of smoking. METHODS: We used cross-sectional survey data from 11 of a total 19 Norwegian counties examined in 1997-99 including 65,875 men and women aged 39-44 years. Analysis of associations were adjusted for confounding by socioeconomic position, health indicators, and additionally for BMI. RESULTS: Compared with never-smokers, when adjusting for confounders and in addition for BMI, mean HC remained lower while mean WC and waist-hip-ratio (WHR) were higher in current smokers. The finding of a lower HC and higher WHR level among smokers was consistent by sex and in strata by levels of education and physical activity, while the finding of higher WC by smoking was less consistent. Among current smokers, BMI-adjusted mean HC decreased whereas WC and WHR increased by volume smoked. Compared with current smokers, former smokers had higher BMI-adjusted HC, lower WHR and among women WC was lower. CONCLUSIONS: The main finding in this study was the consistent negative associations of smoking with HC. In line with the hypothesis that lower percentage gluteofemoral fat is linked with higher cardiovascular risk, our results suggest that smoking impacts cardiovascular risk through mechanisms that reduce the capacity of fat storage in the lower body region.

Impact of snus use in teenage boys on tobacco use in young adulthood; a cohort from the HUNT Study Norway.

BACKGROUND: As smoking rates decreased, the use of Swedish snus (smokeless tobacco) concordantly increased in Norway. The role of snus as possible contributor to the reduction of smoking has been widely discussed. Our aim was to quantitate transitions in snus use, smoking and dual use of snus and cigarettes in a young male population. METHODS: This prospective cohort study includes 1346 boys participating in the Nord-Trøndelag Health Study in Young-HUNT1 1995-97, age 13-19 and in HUNT3 2006-08, age 23-30. Participants reported on tobacco use at both points of time. Models with binominal regression were applied to examine relative risks (RRs), of adolescent ever snus users, dual users or smokers (reference: never tobacco use), to be current snus only users, smokers (including dual users), or tobacco free in adulthood. RESULTS: Current tobacco use in this male cohort increased from 27% in adolescence to 49% in adulthood, increasing more for snus only use and dual use than for smoking only. The adjusted RR (95% CI) of becoming a smoker as young adult, was 2.2 (CI 1.7-2.7) for adolescent snus users, 3.6 (CI 3.0-4.3) for adolescent dual users, and 2.7 (CI 2.2-3.3) for adolescent smokers. RR to become snus only users as adults was 3.1 (2.5-3.9) for adolescent dual users, 2.8 (2.2-3.4) for adolescent snus users and 1.5 (1.0-2.2) for adolescent smokers. The adjusted RR for the transition from adolescent tobacco use to no tobacco use in adulthood was similar for snus users and smokers with RR 0.5 (CI 0.4-0.7), but considerably lower for dual users with RR 0.2 (CI 0.2-0.3). CONCLUSIONS: The use of snus, with or without concurrent smoking, carried a high risk of adult smoking as well as adult snus only use. Dual use seemed to promote the opportunity to become snus only users in adulthood, but made it also more difficult to quit. The benefit of snus use for harm reduction is not evident in our cohort, as the combination of smoking and dual use resulted in high smoking rates among the young adults.

The educational gradient in premature cardiovascular mortality: Examining mediation by risk factors in cohorts born in the 1930s, 1940s and 1950s.

AIMS: Educational inequality in cardiovascular disease and in modifiable risk factors changes over time and between birth cohorts. We aimed to assess how cardiovascular disease risk factors mediate educational differences in premature cardiovascular disease mortality and how this varies over birth cohorts and sex. METHODS: We followed 360,008 40-45-year-olds born in the 1930s, 1940s or 1950s from Norwegian health examination surveys (1974-1997) for premature cardiovascular disease mortality. Cox proportional hazard and Aalen's additive survival analyses provided hazard ratios and rate differences of excess deaths in participants with basic versus tertiary education. RESULTS: Relative educational differences in premature cardiovascular disease mortality were stable, whereas absolute differences narrowed from the 1930s to the 1950s cohorts; rate differences per 100 000 person years declined from 170 (95% confidence interval 117, 224) to 49 (36, 61) in men and from 60 (34, 85) to 23 (16, 29) in women. Cardiovascular disease risk factors attenuated rate differences by 69% in both cohorts in men, and in women by 102% in 1930s and 61% in 1950s cohorts. Smoking had the single strongest influence on the educational differences for men in all three cohorts, and for women in the two most recent cohorts. CONCLUSION: Smoking appeared to be the driving force behind educational differences in premature cardiovascular disease mortality in the 1930s to 1950s birth cohorts for men and in the two recent birth cohorts for women. This suggests that strategies for smoking prevention and cessation might have the strongest impact for reducing educational inequality in premature cardiovascular disease mortality.

Educational inequalities in midlife risk factors for non-communicable diseases in two Norwegian counties 1974-2002.

Background: The absolute educational differences in the mortality of Norwegian women and men increased during 1960-2000 and thereafter levelled off in men, but continued to widen in women. Which of the risk factors for non-communicable diseases (NCDs) might explain these trends? Aim: The aim of this study was to investigate trends in gender-specific, absolute educational differences in established risk factors during 1974-2002. Methods: We used cross-sectional data from 40-45-year-old women and men who participated in one of three health surveys in two counties, from the years 1974-1978, 1985-1988 and 2001-2002. To account for increasing educational attainment through the period we used a regression-based index of inequality (Slope Index of Inequality) to assess the educational gradients over time. Results: From 1974 to 2002, the mean levels of serum total cholesterol and blood pressure decreased and body mass index (BMI) increased in all subgroups by education in both sexes. In men, the educational gradient tended to diminish toward the null for serum total cholesterol and narrowed for systolic blood pressure, but increased for BMI. In women, the educational gradient increased to the double for smoking and increased for triglycerides. Conclusions: In two Norwegian counties, the NCD risk factors showed dynamic patterns during 1974-2002. For blood pressure and serum total cholesterol, the levels showed consistent beneficial changes in all educational subgroups, with a narrowing tendency for educational gradients in men. In women, the educational gradient for smoking increased markedly. Knowledge on midlife trends in the educational gradients of risk factors may help to explain recent and future NCD mortality.

The association between BMI and mortality using early adulthood BMI as an instrumental variable for midlife BMI.

The article aims to describe the association between midlife body mass index (BMI) and cardiovascular disease (CVD)- and all-cause mortality, and to use early adulthood BMI as an instrumental variable for midlife BMI, in order to obtain an estimate less distorted by midlife confounders and reverse causality. Data from Norwegian health surveys (1974-2003) (midlife BMI, smoking, blood pressure, total cholesterol, heart rate), Military Conscription Records, National Tuberculosis Screenings (early adulthood BMI), National Educational Registry and Cause of Death Registry were linked. Participants with data on BMI in early adulthood and midlife were included (n = 148.886). Hazard Ratio (HR) for CVD mortality was higher in men with midlife obesity relative to normal weight (HR = 1.46(95% CI 1.25, 1.70). For all-cause mortality, HR was higher in those with obesity or underweight in midlife relative to normal weight (Men:HR = 1.19(95% CI 1.09, 1.29), HR = 2.49(95% CI 1.81, 3.43) Women:HR = 1.33(95% CI 1.13, 1.56), HR = 1.61(95% CI 1.22, 2.13)). In instrumental variable analyses, increased BMI became more strongly associated with CVD and all-cause mortality, and the increased risk of all-cause mortality among the underweight attenuated.

Cardiovascular risk profile at the age of 40-45 in women with previous hyperemesis gravidarum or hypertensive disorders in pregnancy: A population-based study.

OBJECTIVE: To assess midlife cardiovascular risk profiles in women with a history of hyperemesis or hypertensive disorders in pregnancy compared to women with none of the studied pregnancy complications. STUDY DESIGN: Population-based study. Cardiovascular risk factors at the age of 40-45 among women with previous singleton births only were studied through linkage of the Norwegian Birth Registry and a Norwegian screening program (the Age 40 Program). MAIN OUTCOME MEASURES: Family history of coronary heart disease, body mass index, smoking, physical activity, systolic and diastolic blood pressure, heart rate, cholesterol, triglycerides, antihypertensive treatment and diabetes. RESULTS: Among 178,231 women participating in the Age 40 Program with previous singleton births; 2140 (1.2%) had experienced hyperemesis and 13,348 (7.5%) hypertensive disorders in pregnancy. Women who had suffered from hyperemesis were less physically active. The differences in mean systolic blood pressure and body mass index were probably clinically irrelevant. In women with a history of hypertensive disorders in pregnancy, systolic and diastolic blood pressure and body mass index were higher, and they were more likely to report diabetes in midlife. Women who had suffered from hyperemesis or hypertensive disorders in pregnancy were less likely to be daily smokers. CONCLUSION: Women with hypertensive disorders in pregnancy seemed to have an unfavorable cardiovascular risk profile in midlife compared to women with uncomplicated pregnancies. In contrast there was no consistent evidence of increased risk subsequent to hyperemesis gravidarum. The proportion of daily smokers was lower in women with either of the two pregnancy complications.

Life course socioeconomic position, alcohol drinking patterns in midlife, and cardiovascular mortality: Analysis of Norwegian population-based health surveys.

BACKGROUND: Socioeconomically disadvantaged groups tend to experience more harm from the same level of exposure to alcohol as advantaged groups. Alcohol has multiple biological effects on the cardiovascular system, both potentially harmful and protective. We investigated whether the diverging relationships between alcohol drinking patterns and cardiovascular disease (CVD) mortality differed by life course socioeconomic position (SEP). METHODS AND FINDINGS: From 3 cohorts (the Counties Studies, the Cohort of Norway, and the Age 40 Program, 1987-2003) containing data from population-based cardiovascular health surveys in Norway, we included participants with self-reported information on alcohol consumption frequency (n = 207,394) and binge drinking episodes (≥5 units per occasion, n = 32,616). We also used data from national registries obtained by linkage. Hazard ratio (HR) with 95% confidence intervals (CIs) for CVD mortality was estimated using Cox models, including alcohol, life course SEP, age, gender, smoking, physical activity, body mass index (BMI), systolic blood pressure, heart rate, triglycerides, diabetes, history of CVD, and family history of coronary heart disease (CHD). Analyses were performed in the overall sample and stratified by high, middle, and low strata of life course SEP. A total of 8,435 CVD deaths occurred during the mean 17 years of follow-up. Compared to infrequent consumption (

The importance of early life family factors in the association between cardiovascular risk factors and early cardiovascular mortality.

OBJECTIVE: To explore the importance of early life factors shared by siblings, such as parental socioeconomic position, parental practices, housing and neighbourhood, for the association between cardiovascular disease (CVD) risk factors and mortality from CVD, ischaemic heart disease (IHD) and cerebrovascular disease. METHODS: Norwegian health surveys (1974-2003) were linked with data from the Norwegian Family Based Life Course Study and the Cause of Death Registry. Participants with at least one full sibling among survey participants (n=2 71 643) were included. Data on CVD risk factors, body mass index (BMI), height, systolic blood pressure (SBP) and total cholesterol (TC) were stratified into 'low', 'medium' and 'high' risk, and smoking to 'daily smoking' and 'not daily smoking'. RESULTS: Mean age of participants was 41 years, mean follow-up time was 19 years and during follow-up 2512 died from CVD. For each category of increased risk factor level, the per step HR of CVD mortality was increased by 1.91 (95% CI 1.78 to 2.05) for SBP, 1.67 (1.58 to 1.76) for TC, 1.44 (1.36 to 1.53) for BMI, 1.26 (1.18 to 1.35) for height and 2.89 (2.66 to 3.14) for smoking. In analyses where each sibship (groups of full siblings) had a group-specific baseline hazard, these associations were attenuated to 1.74, 1.51, 1.29, 1.18 and 2.63, respectively. The associations between risk factors and IHD mortality followed the same pattern. CONCLUSION: Early life family factors explained a small part of the association between risk factors and mortality from CVD and IHD in a relatively young sample.

The educational gradient in cardiovascular risk factors: impact of shared family factors in 228,346 Norwegian siblings.

BACKGROUND: Various indicators of childhood socioeconomic position have been related to cardiovascular disease (CVD) risk in adulthood. We investigated the impact of shared family factors on the educational gradient in midlife CVD risk factors by assessing within sibling similarities in the gradient using a discordant sibling design. METHODS: Norwegian health survey data (1980-2003) was linked to educational and generational data. Participants with a full sibling in the health surveys (228,346 individuals in 98,046 sibships) were included. Associations between attained educational level (7-9 years, 10-11 years, 12 years, 13-16 years, or >16 years) and CVD risk factor levels in the study population was compared with the corresponding associations within siblings. RESULTS: Educational gradients in risk factors were attenuated when factors shared by siblings was taken into account: A one category lower educational level was associated with 0.7 (95% confidence interval 0.6 to 0.8) mm Hg higher systolic blood pressure (27% attenuation), 0.4 (0.4 to 0.5) mmHg higher diastolic blood pressure (30%), 1.0 (1.0 to 1.1) more beats per minute higher heart rate (21%), 0.07 (0.06 to 0.07) mmol/l higher serum total cholesterol (32%), 0.2 (0.2 to 0.2) higher smoking level (5 categories) (30%), 0.15 (0.13 to 0.17) kg/m2 higher BMI (43%), and 0.2 (0.2 to 0.2) cm lower height (52%). Attenuation increased with shorter age-difference between siblings. CONCLUSION: About one third of the educational gradients in modifiable CVD risk factors may be explained by factors that siblings share. This implies that childhood environment is important for the prevention of CVD.

Do repeated risk factor measurements influence the impact of education on cardiovascular mortality?

OBJECTIVE: It has been questioned if the excess cardiovascular disease (CVD) mortality by lower educational level can be fully explained by conventional modifiable CVD risk factors. Our objective was to examine whether repeated measures over time of risk factors (smoking, physical inactivity, blood pressure, total cholesterol and body mass index) explain more of the socioeconomic gradient in CVD mortality than if they are measured only once. METHODS: A cohort of 34 884 men and women attended all three screenings (1974-1978, 1977-1983 and 1985-1988) in the Norwegian Counties Study and were followed for CVD mortality through 2009 by linkage to the Norwegian Cause of Death Registry. RESULTS: Age-adjusted and sex-adjusted HR of CVD mortality was 2.32 (95% CI 1.93 to 2.80) for basic relative to tertiary educated individuals. The HR was attenuated by 48% (HR 1.54 (1.28 to 1.87)) when adjusted for CVD risk factors measured at baseline and by 56% (HR 1.45 (1.20 to 1.75)) when two repeated measurements ascertained 5 years apart were added to the model. Similarly, absolute risk difference in CVD mortality by education was attenuated by 62% when adjusted for baseline and by 72% when adjusted for repeated measurements of risk factors. CONCLUSIONS: In this cohort, repeated measurements of risk factors seemed to explain more of the educational gradient in CVD mortality. This suggests that a substantial part of the excess CVD mortality among those with lower education might be explained by conventional risk factors.