Heart failure describing the underlying cause of death – a misconception, lack of information on the true underlying causes or both?

Aim: The underlying cause of death represents the most important information on death certificates. Often, conditions that cannot represent a true underlying cause of death are listed as such. This phenomenon affects the quality of vital statistics and results of studies using cause-specific mortality as endpoints. We aimed at exploring the magnitude and factors associated with the use of heart failure to describe the underlying cause of death. Methods: In this cross-sectional, register based study we linked data from the Norwegian Cause of Death Registry and the Norwegian Patient Registry. We used logistic regression models to analyse the association between external factors and heart failure listed as the underlying cause of death. Results: Heart failure was listed as the underlying cause of death in 3.6% of all deaths. The odds of heart failure increased: (a) by 35% for 5-year increment in age; (b) by 78% for deaths occurring at nursing homes (compared with in-hospital deaths); and (c) by 602% for deaths not followed by an autopsy (compared with those followed by an autopsy). Deceased with a previous hospitalisation with heart failure as the discharge diagnosis had 514% higher odds of having heart failure listed as their underlying cause of death. Of the deceased with heart failure listed as the underlying cause of death, 9.4% did not have any, and 69.2% had only irrelevant additional information for assessing the true underlying cause of death in their death certificates. Conclusions: Heart failure listed as the underlying cause of death was associated with age, place of death, autopsy and previous hospitalisations – all factors that should not influence coding procedures. Better completion of death certificates in accordance with the World Health Organization rules will help reduce the use of heart failure to describe the underlying cause of death.acceptedVersio

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 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

Cervical cancer in women under 30 years of age in Norway: a population-based cohort study

Background We compared women with incident cervical cancer under the age of 30 with older women with regard to stage, morphology, screening history and cervical cancer mortality in a population-based cohort study. Methods We included data from the Cancer Registry of Norway. Incidence rates (per 100,000 women-years) were calculated and joinpoint regression was used to analyse trends. The Nelson-Aalen cumulative hazard function for risk of cervical cancer death during a 15-year follow-up was displayed. The hazard ratios (HRs) of cervical cancer mortality with 95% confidence intervals (CIs) were derived from Cox regression models. Results The incidence of cervical cancer in women under the age of 30 has almost tripled since the 1950s, with the steepest increase during 1955–80 (with an annual percentage change (APC) of 7.1% (95%CI 4.4–9.8)) and also an increase after 2004 (3.8% (95%CI -1.3–9.2)). Out of 21,160 women with cervical cancer (1953–2013), 5.3% were younger than 30 years. A lower proportion of younger women were diagnosed at more advanced stages and a slightly higher proportion were diagnosed with adenocarcinoma and adenosquamous carcinoma comparing women above 30 years. The cumulative risk of cervical cancer death was lower for patients under the age of 30. However, the difference between the age groups decreased over time. The overall adjusted HR of cervical cancer mortality was 0.69 (95% CI 0.58–0.82) in women diagnosed under the age of 30 compared to older women. Conclusion There has been an increase in cervical cancer incidence in women under the age of 30. Cervical cancer in younger women was not more advanced at diagnosis compared to older women, and the cervical cancer mortality was lower.publishedVersio

Lockdown and non-COVID-19 deaths: cause-­specific mortality during the first wave of the 2020 pandemic in Norway: a population-­based register study

Objective To explore the potential impact of the first wave of COVID-19 pandemic on all cause and cause-specific mortality in Norway. Design Population-based register study. Setting The Norwegian cause of Death Registry and the National Population Register of Norway. Participants All recorded deaths in Norway from March to May from 2010 to 2020. Main outcome measures Rate (per 100 000) of all-cause mortality and causes of death in the European Shortlist for Causes of Death from March to May 2020. The rates were age standardised and adjusted to a 100% register coverage and compared with a 95% prediction interval (PI) from linear regression based on corresponding rates for 2010–2019. Results 113 710 deaths were included, of which 10 226 were from 2020. We did not observe any deviation from predicted total mortality. There were fewer than predicted deaths from chronic lower respiratory diseases excluding asthma (11.4, 95% PI 11.8 to 15.2) and from other non-ischaemic, non-rheumatic heart diseases (13.9, 95% PI 14.5 to 20.2). The death rates were higher than predicted for Alzheimer’s disease (7.3, 95% PI 5.5 to 7.3) and diabetes mellitus (4.1, 95% PI 2.1 to 3.4). Conclusions There was no significant difference in the frequency of the major causes of death in the first wave of the 2020 COVID-19 pandemic in Norway compared with corresponding periods 2010–2019. There was an increase in diabetes mellitus and Alzheimer’s deaths. Reduced mortality due to some heart and lung conditions may be linked to infection control measures.publishedVersio

Limited Benefit of Fish Consumption on Risk of Hip Fracture among Men in the Community-Based Hordaland Health Study

Hip fractures have a high prevalence worldwide. Few studies have investigated whether fish consumption is associated with risk of hip fractures. The objective of the present study was to investigate the effect of fish intake on the subsequent risk of a hip fracture because of the low number of studies on this topic. A community-based prospective cohort study of 2865 men and women from Hordaland county in Norway, born between 1925–1927 and enrolled in the study in 1997–1999. Information on hip fracture cases was extracted from hospital records until 31 December 2009. Baseline information on the intake of fish was obtained from a semi-quantitative food frequency questionnaire. Cox proportional hazard regression models with death as a competing risk were used to evaluate the association of fish intake with risk of hip fracture. During a mean (SD) follow-up time of 9.6 (2.7) years, 226 hip fractures (72 in men, 154 in women) were observed. The mean (SD) fish intake was 48 (25) g/1000 kcal. The association between fish intake and risk of hip fracture was not linear and displayed a threshold, with low intake of fish being associated with an increased risk of hip fracture in men (HR (Hazard Ratio) = 1.84, 95% CI 1.10, 3.08). In this community-based prospective study of men and women, a low intake of fish was associated with the risk of a hip fracture in men.publishedVersio

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

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

Smoking, plasma cotinine and risk of atrial fibrillation: the Hordaland Health Study

Background: Cigarette smoking has been identified as a major modifiable risk factor for coronary heart disease and mortality. However, findings on the relationship between smoking and atrial fibrillation (AF) have been inconsistent. Furthermore, findings from previous studies were based on self‐reported smoking. Objective: To examine the associations of smoking status and plasma cotinine levels, a marker of nicotine exposure, with risk of incident AF in the Hordaland Health Study. Methods: We conducted a prospective analysis of 6682 adults aged 46‐74 years without known AF at baseline. Participants were followed via linkage to the Cardiovascular Disease in Norway (CVDNOR) project and the Cause of Death Registry. Smoking status was assessed by both questionnaire and plasma cotinine levels. Results: A total of 538 participants developed AF over a median follow‐up period of 11 years. Using questionnaire data, current smoking (HR: 1.41, 95% CI: 1.09–1.83), but not former smoking (HR: 1.03, 95% CI: 0.83–1.28), was associated with an increased risk of AF after adjustment for gender, age, body mass index, hypertension, physical activity and education. Using plasma cotinine only, the adjusted HR (95% CI) was 1.40 (1.12–1.75) for participants with cotinine ≥85 nmol L−1 compared to those with cotinine <85 nmol L−1. However, the risk increased with elevated plasma cotinine levels until 1199 nmol L−1 (HR: 1.55, 95% CI: 1.16–2.05 at the third group vs. the reference group) and plateaued at higher levels. Conclusions: Current, but not former smokers, had a higher risk of developing AF. Use of plasma cotinine measurement corroborated this finding.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