Alcohol consumption in a Danish cohort during 11 years.

A cohort living in Copenhagen County, originally consisting of 1198 persons, 577 men and 621 women, 40-years of age in 1976, was reexamined in 1981, and again in 1987. Of the original cohort 1052 (88%) participated in 1976, 992 (84%) in 1981, and 965 (85%) in 1987. The purpose of this study was to describe changes in alcohol consumption in the cohort, with the view of identifying subgroups, who have changed their alcohol consumption behaviour to a certain extent. Alcohol consumption was measured by the same questionnaire all three times as to the level of consumption and frequency. Alcohol consumption peaked in 1981 (45-year olds) with 10.4 drinks on average a week. Men increased their consumption by 8% and women by 37%. There was an overall downward tendency in the consumption frequency among men, whereas the opposite was the case among women. The two groups are converging toward a weekly consumption frequency. It seems now that women are leading the change toward a greater wine consumption in relative and absolute terms. It is therefore concluded that female consumption should be considered as a target in future preventive programmes.     

Oral polio vaccine response in the MAL-ED birth cohort study: Considerations for polio eradication strategies

Background

Immunization programs have leveraged decades of research to maximize oral polio vaccine (OPV) response. Moving toward global poliovirus eradication, the WHO recommended phased OPV-to-IPV replacement on schedules in 2012. Using the MAL-ED prospective birth cohort data, we evaluated the influence of early life exposures impacting OPV immunization by measuring OPV response for serotypes 1 and 3.

Respiratory syncytial virus and influenza hospitalizations in Danish children 2010–2016

ObjectiveTo pave the way for universal or risk factor-based vaccination strategies, the present study aimed to describe the epidemiology and compare risk factors for hospitalization associated with respiratory syncytial virus (RSV) and influenza virus infections in Danish children.MethodsNational register-based cohort study among 403,422 Danish children born 2010–2016.ResultsPrior asthma hospitalization, number of children in the household, chronic disease and maternal history of asthma hospitalization were the most important risk factors for both RSV and influenza hospitalization. The incidence of influenza increased at school start.ConclusionsOur findings enable targeted vaccination programs for high-risk children with asthma-like disease, chronic disease, siblings in the household, or maternal history of asthma hospitalization.     

Respiratory cancer in Danish bakers: a 10 year cohort study

A national cohort based on the census at 9 November 1970 and the death registration files from 1970 to 1980 was analysed to see if skilled Danish bakers had an excess of respiratory cancer. The group of skilled bakers was divided into occupational subgroups to try to narrow down the possible causes of cancer. Significant excess mortality was found among skilled bakers in retail bakeries, skilled bakers in hotels and restaurants, and independent bakers. To adjust for confounding factors, the SMR was calculated with control groups of equal social status and smoking habits. With all skilled workers as the reference group, skilled bakers in retail bakeries still had an excess, but now insignificant, risk but skilled bakers in hotels and restaurants had a significant excess risk. Compared with all self employed people in urban occupations in which an average of six or fewer workers were employed as a referent group, independent bakers had an insignificant excess risk. Suspected carcinogens in bakeries include polycyclic aromatic hydrocarbons (PAH), reaction products of PAH, free radicals, n-nitrosodimethylamine, aflatoxin, sterigmatocystin, and zeralenone.     

Respiratory cancer in Danish bakers: a 10 year cohort study.

A national cohort based on the census at 9 November 1970 and the death registration files from 1970 to 1980 was analysed to see if skilled Danish bakers had an excess of respiratory cancer. The group of skilled bakers was divided into occupational subgroups to try to narrow down the possible causes of cancer. Significant excess mortality was found among skilled bakers in retail bakeries, skilled bakers in hotels and restaurants, and independent bakers. To adjust for confounding factors, the SMR was calculated with control groups of equal social status and smoking habits. With all skilled workers as the reference group, skilled bakers in retail bakeries still had an excess, but now insignificant, risk but skilled bakers in hotels and restaurants had a significant excess risk. Compared with all self employed people in urban occupations in which an average of six or fewer workers were employed as a referent group, independent bakers had an insignificant excess risk. Suspected carcinogens in bakeries include polycyclic aromatic hydrocarbons (PAH), reaction products of PAH, free radicals, n-nitrosodimethylamine, aflatoxin, sterigmatocystin, and zeralenone.     

Increased hospitalizations of elderly patients

This issue of Emerging Infectious Diseases contains 2 articles that report increases in England in the incidence of hospitalizations for specific diseases, one on pneumonias and the other on community-acquired staphylococcal diseases. Both articles report increases in disease among those >65 years of age.     

Respiratory distress syndrome in preterm infants and risk of epilepsy in a Danish cohort

Infant respiratory distress syndrome (IRDS) may be complicated by intracerebral hemorrhage, a known trigger of epilepsy. However, few data exist on long term epilepsy risk following IRDS. We therefore examined the association between IRDS in preterm infants and childhood epilepsy. We conducted a population-based cohort study using individual-level data linkage among nationwide registries. All infants born at 32–36 weeks of gestation in 1978–2009 were identified in the Medical Birth Registry. We identified children with IRDS and those with epilepsy using the Danish National Patient Registry. We computed the cumulative incidence of epilepsy with follow-up from birth until epilepsy, emigration, death, age 15, or December 31, 2014. We used Cox’s regression analysis to compute hazard ratios comparing children with and without IRDS, adjusting for sex, birth year, gestational age, multiplicity, major malformations, and maternal age. We identified 95,026 infants, of whom 6426 (6.8%) had IRDS. The cumulative incidence of epilepsy was 3.4% by age 15 in children with IRDS and 2.1% in children without IRDS. The adjusted hazard ratio of epilepsy among children with IRDS compared to those without was 1.4 (95% CI 1.2–1.6). When we restricted the IRDS cohort to children with no simultaneous morbidities that had clinical symptoms overlapping with IRDS, the overall adjusted HR was 1.1 (95% CI 0.9–1.4). In children born preterm at 32–36 weeks’ gestation, IRDS was associated with increased risk of childhood epilepsy.     

Cancer incidence among Danish seafarers: a population based cohort study

Aims: Seafarers aboard oil and chemical tankers may be exposed to many chemicals, including substances like benzene that are known to be carcinogenic. Other seafarers are exposed to engine exhaust, different oil products, and chemicals used aboard and some years ago asbestos was also used extensively in ships. The aim of this study was to study cancer morbidity among Danish seafarers in relation to type of ship and job title. Methods: A cohort of all Danish seafarers during 1986–1999 (33 340 men; 11 291 women) registered by the Danish Maritime Authority with an employment history was linked with the nationwide Danish Cancer Registry and followed up for cancer until the end of 2002. The number of person years at risk was 517 518. Standardised incidence ratios (SIR) were estimated by use of the corresponding national rates. Results: The SIR of all cancers combined was higher than expected: 1.26 (95% CI 1.19 to 1.32) for men and 1.07 (95% CI 0.95 to 1.20) for women. This was mainly due to an excess of cancer of the larynx, lung, tongue, mouth, pharynx, oesophagus, pancreas, kidney, urinary bladder, colon, and bone as well as skin melanomas among men (the three latter borderline significantly increased), and an excess of cancer of the lung, rectum, and cervix uteri among women. The differences in risk pattern for lung cancer between the different job categories among men ranged in terms of SIR from 1.2 (95% CI 0.9 to 1.7) (engine officers) to 2.3 (1.6 to 3.3) (engine room crew), and 4.1 (2.1 to 7.4) among maintenance crew. Non-officers had a 1.5 times higher lung cancer risk than officers. No increased occurrence of all lymphatic and haematopoietic malignancies combined was found for employees on tankers, but the number of cases was limited to a total of 7. Conclusions: Danish seafarers, especially men, face an increased overall cancer risk, in particular a risk for lung cancer and other tobacco associated cancers.     

Background and design of a Danish cohort study of workers in phenoxy herbicide manufacture

In 1982, a Danish cohort study was initiated of workers in the manufacture of 2,4-dichlorophenol- and 4-chloro-ortho-cresol-based phenoxy herbicides, after a governmental working group had indicated the need for further data on the long-term health consequences of exposure to these phenoxy herbicides. A cohort study of workers in the manufacture of these substances was considered to be a valuable supplement to the Swedish case-control studies of patients exposed mainly in spraying. Manufacture of phenoxy herbicides was commenced in Denmark by Kemisk Vaerk Koege (KVK) in 1947, and this company has produced 2,4-D and MCPA, and later 2,4-DP and MCPP. Very limited amounts of 2,4,5-T have been processed in this plant, mainly in the formation of esters based on a purchased acid. Manufacture of MCPA was commenced by Esbjerg Kemikaliefabrik (EK) in 1951, and this production was later supplemented with 2,4-DP. Furthermore, MCPA was produced by Cheminova and Danske Gasvaerkers Tjaerekompagni for short periods in the late 1950s. All persons employed at KVK and EK from the time when these plants began operation, in 1933 and 1951 respectively, until 1982 were intended to be included in this cohort study. The registration was based on company records and, from 1964 onward, supplemented with data from a public pension scheme (ATP). Linkage of company records from KVK with ATP records for the overlapping period 1964-1980 showed 2,163 persons to be known in both datasets, whereas 614 persons were known only from the ATP records. The data collection has consequently shown that ATP provides a valuable data source for control of company records in Denmark. For the study period before 1964, the number of registered employees could be controlled by comparison with the number of employees reported by the companies on questionnaires for the national industrial statistics 1945-1969. In the analysis of this cohort study, special attention was given to soft tissue sarcomas and malignant lymphomas, which are the diagnostic groups associated with exposure to phenoxy herbicides in the Swedish case-control studies. Soft tissue sarcomas, in both organs and connective tissue, can be identified using the classifications found in the Danish Cancer Registry.     

Trivalent inactivated influenza vaccine is not associated with sickle cell hospitalizations in adults from a large cohort

We evaluated the risk of hospitalization for sickle cell crisis (SCC) following influenza vaccination (trivalent inactivated vaccine, TIV) in adults with sickle cell disease. The cohort consisted of all adults aged 18years and older who had a diagnosis of sickle cell disease in the Vaccine Safety Datalink from 1991 to 2006. The outcome measure was any hospitalization for SCC with the main exposure being influenza vaccine. We used a self controlled case series design to compare the incidence rates of hospitalization for SCC during the exposed and unexposed periods after TIV. No significant association between influenza vaccination and hospitalization for sickle cell crisis was found (IRR ratio 0.92, 95% confidence limits 0.66-1.28). These results provide evidence that the seasonal influenza vaccine is safe as recommended in adults who are at high risk for complications of influenza sequelae due to sickle cell disease.     

Predictors of changes in physical activity in a prospective cohort study of the Danish adult population

AIM: To investigate predictors of changes in physical activity, in a prospective population-based study. METHODS: Data were from the Danish Health Interview Surveys in 1994 and 2000, and included persons between 16 and 64 years of age who answered the questions on physical activity and various covariates in 1994, and who were re-interviewed in 2000. In total 2,957 subjects participated (62% of the original sample). Data were analysed using logistic regression. RESULTS: Predictors of physical inactivity were, for men and women respectively, heavy smoking (odds ratio (OR) 2.07, 95% confidence interval (CI) 1.24-3.48, and OR 2.23, 95% CI 1.34-3.71), poor self-rated health (OR 2.11, 95% CI 1.25-3.58, and OR 1.75, 95% CI 1.10-2.80), and believing that one's own effort has no effect on health (OR 1.86, 95% CI 1.20-2.88, and OR 1.63, 95% CI 1.00-2.65). For men, further predictors for physical inactivity were obesity as compared to normal weight (OR 2.10, 95% CI 1.11-3.98), and being unmarried as compared to being married (OR 2.22, 95% CI 1.40-3.51). The only predictor for becoming physically active among initially sedentary respondents was meeting often with family (p=0.011). CONCLUSIONS: Our results show a number of strong predictors for physical inactivity. Variables of an unhealthy lifestyle tend to cluster in some individuals, and physical inactivity interventions may therefore be more successful if they also address smoking, self-belief, and obesity. Interventions tailored to raise inactive people's level of activity should focus on social support from the family.     

Identification and reproducibility of dietary patterns in a Danish cohort: the Inter99 study

We aimed to identify dietary patterns in a Danish adult population and assess the reproducibility of the dietary patterns identified. Baseline data of 3,372 women and 3,191 men (30-60 years old) from the population-based survey Inter99 was used. Food intake, assessed by a FFQ, was aggregated into thirty-four separate food groups. Dietary patterns were identified by principal component analysis. Confirmatory factor analysis and Bland Altman plots were used to assess the reproducibility of the dietary patterns identified. The Bland Altman plots were used as an alternative and new method. Two factors were retained for both women and men, which accounted for 15.1-17.4 % of the total variation. The 'Traditional' pattern was characterised by high loadings ( > or = 0.40) on paté or high-fat meat for sandwiches, mayonnaise salads, red meat, potatoes, butter and lard, low-fat fish, low-fat meat for sandwiches, and sauces. The 'Modern' pattern was characterised by high loadings on vegetables, fruit, mixed vegetable dishes, vegetable oil and vinegar dressing, poultry, and pasta, rice and wheat kernels. Small differences were observed between patterns identified for women and men. The root mean square error approximation from the confirmatory factor analysis was 0.08. The variation observed from the Bland Altman plots of factors from explorative v. confirmative analyses and explorative analyses from two sub-samples was between 18.8 and 47.7 %. Pearson's correlation was >0.89 (P < 0.0001). The reproducibility was better for women than for men. We conclude that the 'Traditional' and 'Modern' dietary patterns identified were reproducible.