Evaluation of incomplete maternal smoking data using machine learning algorithms: a study from the Medical Birth Registry of Norway

Background The Medical Birth Registry of Norway (MBRN) provides national coverage of all births. While retrieval of most of the information in the birth records is mandatory, mothers may refrain to provide information on her smoking status. The proportion of women with unknown smoking status varied greatly over time, between hospitals, and by demographic groups. We investigated if incomplete data on smoking in the MBRN may have contributed to a biased smoking prevalence. Methods In a study population of all 904,982 viable and singleton births during 1999–2014, we investigated main predictor variables influencing the unknown smoking status of the mothers’ using linear multivariable regression. Thereafter, we applied machine learning to predict annual smoking prevalence (95% CI) in the same group of unknown smoking status, assuming missing-not-at-random. Results Overall, the proportion of women with unknown smoking status was 14.4%. Compared to the Nordic country region of origin, women from Europe outside the Nordic region had 15% (95% CI 12–17%) increased adjusted risk to have unknown smoking status. Correspondingly, the increased risks for women from Asia was 17% (95% CI 15–19%) and Africa 26% (95% CI 23–29%). The most important machine learning prediction variables regarding maternal smoking were education, ethnic background, marital status and birth weight. We estimated a change from the annual observed smoking prevalence among the women with known smoking status in the range of − 5.5 to 1.1% when combining observed and predicted smoking prevalence. Conclusion The predicted total smoking prevalence was only marginally modified compared to the observed prevalence in the group with known smoking status. This implies that MBRN-data may be trusted for health surveillance and research.publishedVersio

Dietary correlates of an at-risk BMI among Inuit adults in the Canadian high arctic: cross-sectional international polar year Inuit health survey, 2007-2008

Background: The study’s objective was to investigate the dietary correlates of an at-risk body mass index (BMI) among Inuit adults from thirty-six communities across the Canadian Arctic using data from the cross-sectional International Polar Year Inuit Health Survey, conducted in 2007–2008. Methods: The survey included assessments of 24-hr dietary recall, sociodemographics, physical activity, and anthropometry. Dietary characteristics of overweight and obesity were similar and therefore combined into one at- risk BMI category (≥25 kg/m2) for analyses. The relationship between an at-risk BMI and energy intake from macronutrients, high sugar drinks, high-fat foods, saturated fatty acids, and traditional foods were examined entering each dietary variable separately into a logistic regression model as an independent variable. Analyses were adjusted for age, sex, region, kcalories, walking, smoking and alcohol consumption. Further multivariable models considered selected dietary variables together in one model. Results: An at-risk BMI was present for 64% with a prevalence of overweight and obesity of 28% and 36%, respectively. Consumption of high-sugar drinks (>15.5% E) was significantly related with having an at-risk BMI (OR = 1.6; 95% CI 1.2; 2.2), whereas the % E from total carbohydrate evaluated as a continuous variable and as quartiles was inversely related to an at-risk BMI (P -trend < 0.05) in multivariable analyses. While % E from high-fat foods was positively related to an at-risk BMI, the findings were not significant in a model controlling for high-sugar drinks and % E from carbohydrates. Conclusions: The prevalence of overweight and obesity is of public health concern among Inuit. The current findings highlight the obesogenic potential of high-sugar drink consumption in an ethnically distinct population undergoing rapid cultural changes and raises concerns regarding carbohydrate restricted diets. Health promotion programs aimed at preventing the development of an unhealthy body weight should focus on physical activity and the promotion of healthy diets with reduced intake of sugar drinks.publishedVersio

Association between pregravid physical activity and family history of stroke and risk of stillbirth: Population-based cohort study

Objectives: To evaluate whether family history of disease and pregravid lifestyle and cardiovascular risk factors are associated with subsequent stillbirth delivery. Design: Prepregnancy cohort study. Setting: Cohort Norway regional health surveys (1994–2003) linked to Medical Birth Registry of Norway for deliveries through 2012. Participants: 13 497 singleton births (> 22 weeks gestation) in 8478 women. Main outcome measure: Risk of stillbirth evaluated by Poisson regression. Results: Mean (SD) length of follow-up was 5.5 (3.5) years. In analyses adjusting for baseline age and length of follow-up, ≥3 hours of baseline past-year vigorous physical activity per week (resulting in shortness of breath/sweating) was associated with increased risk of stillbirth compared with 18.5 and <25 kg/m2). Vigorous activity of ≥3 hours per week (IRR of 4.50; 95% CI 1.72 to 11.79) and a family history of stroke (IRR of 3.81; 95% CI 1.31 to 11.07) were more strongly related to stillbirth risk among women with a normal BMI than that observed for all women combined. Established risk factors also associated with stillbirth risk. Conclusions: The study identified physical activity and family history of stroke as potential new risk factors for stillbirth delivery.publishedVersio

Red blood cell folate levels in Canadian Inuit women of childbearing years: influence of food security, body mass index, smoking, education, and vitamin use

Background: The benefits of folic acid for prevention of congenital anomalies are well known. For the Inuit of Canada, where vitamin use is low and access to folate-rich foods limited, fortification is likely a major source of intake. We sought to determine whether red blood cell folate (RBCF) levels of Inuit women reached accepted target levels. Methods: The Inuit Health Survey, 2007–2008, included evaluation of RBCF levels among 249 randomly selected non-pregnant women of reproductive age. Using descriptive statistics and linear regression analyses, RBCF levels were assessed and compared across several socio-demographic variables to evaluate the characteristics associated with RBCF status. Results: Mean (SD) RBCF levels of 935.5 nmol/L (± 192) reached proposed target levels (> 906 nmol/L); however, 47% of women had lower than target levels. In bivariate analysis, non-smoking, higher education, higher income, food security, increased body mass index, and vitamin use were each significantly associated with higher RBCF. Increased levels of smoking had a negative association with RBCF levels (− 5.8 nmol/L per cigarette smoked per day (p = 0.001)). A total of 6.8% of women reported taking vitamin supplements, resulting in a 226 nmol/L higher RBCF level on average compared to non-users (p < 0.001). Conclusion: While mean levels of folate reached target levels, this was largely driven by the small number of women taking vitamin supplements. Our results suggest that folate status is often too low in Inuit women of childbearing years. Initiatives to improve food security, culturally relevant education on folate-rich traditional foods, vitamin supplements, and smoking cessation/reduction programs may benefit Inuit women and improve birth outcomes.publishedVersio

Low serum magnesium concentrations are associated with a high prevalence of premature ventricular complexes in obese adults with type 2 diabetes

<p>Abstract</p> <p>Background</p> <p>Premature ventricular complexes (PVC) predict cardiovascular mortality among several adult populations. Increased arrhythmia prevalence has been reported during controlled magnesium (Mg) depletion studies in adults. We thus hypothesized that serum magnesium (sMg) concentrations are inversely associated with the prevalence of PVC in adults at high cardiovascular risk.</p> <p>Methods</p> <p>Anthropometric, demographic and lifestyle characteristics were assessed in 750 Cree adults, aged > 18 yrs, who participated in an age-stratified, cross-sectional health survey in Quebec, Canada. Holter electrocardiograms recorded heart rate variability and cardiac arrhythmias for two consecutive hours. Multivariate logistic regression was used to evaluate the associations between sMg and PVC.</p> <p>Results</p> <p>PVC prevalence in adults with hypomagnesemia (sMg ≤ 0.70 mmol/L) was more than twice that of adults without hypomagnesemia (50% vs. 21%, <it>p </it>= 0.015); results were similar when adults with cardiovascular disease history were excluded. All hypomagnesemic adults with PVC had type 2 diabetes (T2DM). Prevalence of PVC declined across the sMg concentration gradient in adults with T2DM only (<it>p </it>< 0.001 for linear trend). In multivariate logistic regressions adjusted for age, sex, community, body mass index, smoking, physical activity, alcohol consumption, kidney disease, antihypertensive and cholesterol lowering drug use, and blood docosahexaenoic acid concentrations, the odds ratio of PVC among T2DM subjects with sMg > 0.70 mmol/L was 0.24 (95% CI: 0.06-0.98) <it>p </it>= 0.046 compared to those with sMg ≤ 0.70 mmol/L.</p> <p>Conclusions</p> <p>sMg concentrations were inversely associated with the prevalence of PVC in patients with T2DM in a dose response manner, indicating that suboptimal sMg may be a contributor to arrhythmias among patients with T2DM.</p

Mortality following first-time hospitalization with acute myocardial infarction in Norway, 2001-2014: Time trends, underlying causes and place of death

Background Trends on cause-specific mortality following acute myocardial infarction (AMI) are poorly described and no studies have analyzed where do AMI patients die. We analyzed trends in 28-day and one-year mortality following an incident AMI with focus on changes over time in the underlying cause and place of death. Methods We identified in the ‘Cardiovascular Disease in Norway’ Project all patients 25+ years, hospitalized with an incident AMI in Norway, 2001–2014. Information on date, underlying cause and place of death was obtained from the Cause of Death Registry. Results Of 144,473 patients included in the study, 11.4% died within first 28 days. The adjusted 28-day mortality declined by 5.2% per year (ptrend < 0.001). Of 118,881 patients surviving first 28 days, 10.1% died within one year. The adjusted one-year CVD mortality declined by 6.2% per year (ptrend < 0.001) while non-CVD mortality increased by 1.4% per year (ptrend < 0.001), mainly influenced by increased risk of dying from neoplasms. We observed a shift over time in the underlying cause of death toward more non-CVD deaths, and in the place of death toward more deaths occurring in nursing homes. Conclusions We observed a decline in 28-day mortality following an incident AMI hospitalization. One-year CVD mortality declined while one-year risk of dying from non-CVD conditions increased. The resulting shift toward more non-CVD deaths and deaths occurring outside a hospital need to be considered when formulating priorities in treating and preventing adverse events among AMI survivors.acceptedVersio

Heart failure in Norway, 2000-2014: analyzing incident, total and readmission rates using data from the Cardiovascular Disease in Norway (CVDNOR) Project

Postponed access until 23rd October 2020.Aims To examine trends in heart failure (HF) hospitalization rates and risk of readmissions following an incident HF hospitalization. Methods and results During 2000–2014, we identified in the Cardiovascular Disease in Norway Project 142 109 hospitalizations with HF as primary diagnosis. Trends of incident and total (incident and recurrent) HF hospitalization rates were analysed using negative binomial regression models. Changes over time in 30-day and 3-year risk of HF recurrences or cardiovascular disease (CVD)-related readmissions were analysed using Fine and Grey competing risk regression, with death as competing events. Age-standardized rates declined on average 1.9% per year in men and 1.8% per year in women for incident HF hospitalizations (both Ptrend < 0.001) but did not change significantly in either men or women for total HF hospitalizations. In men surviving the incident HF hospitalization, 30-day and 3-year risk of a HF recurrent event increased 1.7% and 1.2% per year, respectively. Similarly, 30-day and 3-year risk of a CVD-related hospitalization increased 1.5% and 1.0% per year, respectively (all Ptrend < 0.001). No statistically significant changes in the risk of HF recurrences or CVD-related readmissions were observed among women. In-hospital mortality for a first and recurrent HF episode declined over time in both men and women. Conclusions Incident HF hospitalization rates declined in Norway during 2000–2014. An increase in the risk of recurrences in the context of reduced in-hospital mortality following an incident and recurrent HF hospitalization led to flat trends of total HF hospitalization rates.acceptedVersio

Heart Failure Complicating Acute Myocardial Infarction; Burden and Timing of Occurrence: A Nation-wide Analysis Including 86 771 Patients From the Cardiovascular Disease in Norway (CVDNOR) Project

Background: Coronary heart disease (CHD) represents often the underlying conditions for the development of heart failure (HF). We aimed at exploring the burden and timing of HF complicating an acute myocardial infarction (AMI), using the total population of AMI patients hospitalized during 2001–2009 in Norway. Methods and Results: A total of 86 771 patients with a first AMI during 2001–2009 and without previous HF were identified in the “Cardiovascular Disease in Norway” project and followed until HF development, death, or December 31, 2009. In 16 219 patients (18.7%), HF was present on admission or developed during hospitalization for the incident AMI. HF occurrence varied according to age (8.9%, 15.2%, and 25.6% among men and 10.2%, 16.8%, and 27.1% among women ages 25–54, 55–74, and 75–85 years). Among 63 853 patients discharged alive without HF, 8058 (12.6%) were hospitalized with or died because of HF during a median follow‐up time of 3.2 years. HF incidence rates (IRs) per 1000 person‐years during follow‐up were 31 (95% CI, 30–32) for men and 46 (95% CI, 44–47) for women (P<0.01). IRs of HF were highest during the first 6 months of follow‐up, after which they leveled off and remained stable until the end of follow‐up. Conclusions: In this nation‐wide cohort study, we observed that HF remains a frequent complication of the first AMI; both during the acute phase and shortly after the discharge from the hospital.publishedVersio

Association of dietary vitamin K and risk of coronary heart disease in middle-age adults: the Hordaland Health Study Cohort

Objective: The role of vitamin K in the regulation of vascular calcification is established. However, the association of dietary vitamins K1 and K2 with risk of coronary heart disease (CHD) is inconclusive. Design: Prospective cohort study. Setting: We followed participants in the community-based Hordaland Health Study from 1997 - 1999 through 2009 to evaluate associations between intake of vitamin K and incident (new onset) CHD. Baseline diet was assessed by a past-year food frequency questionnaire. Energy-adjusted residuals of vitamin K1 and vitamin K2 intakes were categorised into quartiles. Participants: 2987 Norwegian men and women, age 46–49 years. Methods: Information on incident CHD events was obtained from the nationwide Cardiovascular Disease in Norway (CVDNOR) Project. Multivariable Cox regression estimated HRs and 95% CIs with test for linear trends across quartiles. Analyses were adjusted for age, sex, total energy intake, physical activity, smoking and education. A third model further adjusted K1 intake for energy-adjusted fibre and folate, while K2 intake was adjusted for energy-adjusted saturated fatty acids and calcium. Results: During a median follow-up time of 11 years, we documented 112 incident CHD cases. In the adjusted analyses, there was no association between intake of vitamin K1 and CHD (HRQ4vsQ1 = 0.92 (95% CI 0.54 to 1.57), p for trend 0.64), while there was a lower risk of CHD associated with higher intake of energy-adjusted vitamin K2 (HRQ4vsQ1 = 0.52 (0.29 to 0.94), p for trend 0.03). Further adjustment for potential dietary confounders did not materially change the association for K1, while the association for K2 was slightly attenuated (HRQ4vsQ1 = 0.58 (0.28 to 1.19)). Conclusions: A higher intake of vitamin K2 was associated with lower risk of CHD, while there was no association between intake of vitamin K1 and CHD.publishedVersio

Treatment and 30-day mortality after myocardial infarction in prostate cancer patients: A population-based study from Norway

Introduction: There is limited knowledge about the use of invasive treatment and mortality after acute myocardial infarction (AMI) in prostate cancer (PCa) patients. We therefore wanted to compare rates of invasive treatment and 30-day mortality between AMIs in patients with PCa and AMIs in the general Norwegian male population. Methods: Norwegian population-based registry data from 2013 to 2019 were used in this cohort study to identify AMIs in patients with a preceding PCa diagnosis. We compared invasive treatment rates and 30-day mortality in AMI patients with PCa to the same outcomes in all male AMI patients in Norway. Invasive treatment was defined as performed angiography with or without percutaneous coronary intervention or coronary artery bypass graft surgery. Standardized mortality (SMR) and incidence ratios, and logistic regression were used to evaluate the association between PCa risk groups and invasive treatment. Results: In 1,018 patients with PCa of all risk groups, the total rates of invasive treatment for AMIs were similar to the rates in the general AMI population. In patients with ST-segment elevation AMIs, rates were lower in metastatic PCa compared to localized PCa (OR 0.15, 95% CI: 0.04–0.49). For non-ST-segment elevation AMIs, there were no differences between PCa risk groups. The 30-day mortality after AMI was lower in PCa patients than in the total population of similarly aged AMI patients (SMR 0.77, 95% CI: 0.61–0.97). Conclusion: Except for patients with metastatic PCa experiencing an ST-segment elevation AMI, PCa patients were treated as frequent with invasive treatment for their AMI as the general AMI population. 30-day all-cause mortality was lower after AMI in PCa patients compared to the general AMI population.publishedVersio