In 1990 and 1998 15-41-year-old people were patch-tested in 2 cross-sectional studies of random samples of the population in the western part of Copenhagen County, Denmark. In 1990, 290 subjects and in 1998, 469 subjects were patch-tested. The participation rates were 69% and 51%, respectively. Contact sensitivity to one or more haptens was found in 15.9% and 18.6% in 1990 and 1998, respectively. Nickel sensitivity is still the most common contact sensitivity. The risk of contact sensitivity to the cosmetic-related haptens included in the series (formaldehyde was not included) increased significantly from 2.4% in 1990 to 5.8% in 1998 (odds ratio 2.44, 95% confidence interval 1.04-5.73). The prevalence of contact sensitivity to cosmetic-related allergens has been doubled between 1990 and 1998.
OBJECTIVES: To assess the development in frequency and clustering of hypertension, hypercholesterolaemia, high body mass index (BMI), physical inactivity and tobacco smoking in the period 1964-1992, and to evaluate any sex and age differences. DESIGN: Five cross-sectional investigations on cardiovascular risk factors performed in 1964, 1978, 1982-1984, 1986-1987 and 1991-1992 comprising random samples in a suburban area of Copenhagen, Denmark. Physical activity during leisure time and smoking habits were assessed by self-administered questionnaire. Blood pressure, weight, height and serum total cholesterol were measured according to WHO standards. RESULTS: A total of 8644 persons aged 30, 40, 50 and 60 years participated with an equal number of men and women. Women had fewer risk factors than men and younger persons had fewer risk factors than older persons. In the period 1964-1992 there was a decreasing number of risk factors. The 50 year olds show a sex difference in the period 1982-1992, whereas there was no sex difference among the 60 year olds. Tobacco smoking was the most common risk factor. BMI > 27.5 has become more and more frequent throughout the period, especially in men. The BMI has conquered third place in all age groups. The association of BMI > 27.5 and sedentary leisure time physical activity has become the most frequent. CONCLUSION: Clustering among risk factors decreased over time in both sexes. The association of elevated BMI and sedentary leisure time activity may contribute to the rising frequency of chronic disease such as diabetes mellitus and cardiovascular disease.
Does Helicobacter pylori infection explain all socio-economic differences in peptic ulcer incidence? Genetic and psychosocial markers for incident peptic ulcer disease in a large cohort of Danish adults.
Peptic ulcer epidemiology has changed considerably within the past century. The aim of this study was to assess the 11-year cumulative incidence of peptic ulcer disease and examine the relationship between ulcer incidence and psychosocial and genetic factors.
A random sample of 2416 Danish adults with no history of peptic ulcer disease residing in Copenhagen County, Denmark, attended a population-based prospective cohort study in 1983 and 1994. All participants reported whether they had had an ulcer diagnosed within the observation period. Information on socio-economic factors, family history of peptic ulcer disease (PUD) and lifestyle practices was obtained from a questionnaire. Lewis blood group antigens were assessed from blood samples and Helicobacter pylori infection status was determined with an in-house IgG ELISA.
The overall 11-year cumulative incidence proportion of PUD was 2.9% (95% CI (2.2; 3.6)), i.e. 1.6% (95% CI (1.1; 2.1)) for duodenal ulcer, and 1.3% (95% CI (0.8; 1.7)) for gastric ulcer. Poor socio-economic status increased the risk of PUD independently of H. pylori infection (odds ratio 2.7, 95% CI (1.1; 6.1)) and accounted for 17% of all ulcer cases. High physical activity at work increased the risk of PUD in people infected with H. pylori (odds ratio 2.6, 95% CI (0.8; 8.0)). Family history of PUD or Lewis blood group antigens did not relate to ulcer incidence.
Poor socio-economic status is an important risk factor for PUD that exerts its effect independently of H. pylori infection. Strenuous work may increase the risk of PUD in people with H. pylori infection. Genetic factors do not influence the risk of PUD in Danish adults.
The study presents results from a five-year follow-up on abdominal symptoms in an age and sex stratified random sample of 4,581 Danes. Abdominal pain occurred significantly more often among women (prevalence: 49%, incidence: 21%) compared to mean (prevalence: 38%, incidence: 15%). Five years later the pain had disappeared in 43% of the men and 31% of the women (p = 0.003). Distension, borborygmi, and altering consistency of stools occurred with a prevalence of approximately 50% and an incidence of approximately 30%, significantly more often among women compared to men. Five years later these symptoms had disappeared in about 20%. Prevalence of both heartburn and acid regurgitation were significantly higher among men (38%) than women (30%), whereas no sex difference was observed regarding incidence of these symptoms (16%). Approximately 30% of subjects who had experienced heartburn or acid regurgitation did not do so five years later. In conclusion, abdominal symptoms occur frequently and recurrently in the general population. This information is of importance to doctors when they evaluate patients with abdominal complaints, but no obvious organic etiology.
Studies of incidence of contact allergy in a general population have not been reported. Data from incidence studies may support and direct strategies for prevention of contact allergy and allergic contact dermatitis.
To study the incidence of contact allergy and evaluate risk factors for developing contact allergy in an adult general population sample.
In 1990 a random sample of 567 persons of the 15-69-year-old population living in the western part of Copenhagen County (Denmark) was patch tested in a cross-sectional study. In 1998 a follow-up study was performed. Of 540 invited, 365 (68%) were patch tested again.
In the follow-up study, 37 persons (12%) of the 313 patch-test-negative persons in 1990 had developed one or more positive patch tests (incident contact allergy). Twenty cases (6%) of incident nickel allergy and 25 cases (8%) of incident contact allergy to one or more haptens other than nickel were found. The data indicate that female sex, young age and ear piercing (before 1990) were risk factors for developing nickel allergy. Between 1990 and 1998 metal contact dermatitis was reported in seven women with incident nickel allergy. Six of these women had bought the eliciting item in Denmark before 1995, when vigorous control of the Danish nickel legislation was introduced.
We found a considerable number of incident cases of contact allergy in the adult population. The results of the study support the actions taken to restrict the use of the allergens most frequently encountered, and to increase the labelling demands to products intended for prolonged contact with the skin or a combined action.
With the aim to assess the clustering of abdominal symptoms in a random population, data from a cohort study of a 70 year old Danish population were analysed. The cohort comprised 1,119 subjects of which 72% participated in a primary study and 91% of the survivors in a similar study five years later. The following clusters of symptoms were constantly associated. One group constituted abdominal distension, borborygmi, altering stool consistency and number of bowel movements. Pain relieved by bowel movement was associated with this cluster. Nausea and vomiting comprised another cluster. Heartburn/acid regurgitation did not show a consistent association to any other symptoms and may be considered as a cluster of it own. Pain characteristics traditionally related to upper dyspepsia did not specifically relate to any cluster. It is concluded that, in this 70-year-old population abdominal symptoms occur in clusters comparable to clusters in younger populations. The clusters, however, does not totally confirm the traditional concept of Upper Dyspepsia and Irritable Bowel Syndrome.
Changes in lifestyle or environmental factors are responsible for the increasing prevalence of allergic respiratory disease. Establishing the time at which the increase began may provide a clue as to what factors possibly could have contributed to the increase. Many cross-sectional studies have shown that the prevalence of allergic sensitization decreases with increasing age. This could reflect the natural course of allergic sensitization. Alternatively, this could reflect that the increase in sensitization is caused by a cohort effect, i.e. an increase among subjects born during recent decades.
The aim was to investigate age-specific changes in the prevalence of allergic sensitization in a cohort of adults.
A total of 599 subjects aged 15 to 69 years participated in a cross-sectional general population study in 1990. In 1998 they were invited to a follow-up, and 64.4% (386/599) were reexamined. Serum samples obtained from the participants in 1990 and 1998 were analysed for specific IgE to six common inhalant allergens with the same assay.
The prevalence of allergic sensitization (specific IgE to at least one allergen) increased among subjects who were less than c. 30 years at baseline (1990), i.e. subjects born during the 1960s or later, while the prevalence was unchanged among subjects who were more than c. 30 years at baseline.
The results support the notion that the increasing prevalence of allergic respiratory disease is caused by a cohort effect. Thus, changes in lifestyle or environmental factors that occurred around or after 1960 may have contributed to this increase.
Peptic ulcer prevalence and five year incidence were assessed in a sex and age stratified population sample of 3608 Danish subjects aged 30-60 years. Statements of peptic ulcer disease obtained from questionnaires were scrutinised by reviewing medical records. Life time ulcer prevalence (95% confidence intervals) was 5.6 (4.9-6.4) per cent. Male to female prevalence ratio was 2.2:1, and duodenal to gastric ulcer prevalence ratio was 3.8:1. Thirty two participants with no previous history of peptic ulceration developed an ulcer within the observation period resulting in a five year ulcer incidence of 11.3 (7.4-15.2) per 1000 persons at risk with no demonstrable sex difference. The prevalence of duodenal ulcer has declined in Denmark whereas gastric ulcer prevalence in men has increased slightly. A decline in male duodenal ulcer incidence has probably contributed to the low male to female ulcer incidence ratio, implying that women today incur the same risk of developing an ulcer as men. If such trends continue, they will bring about a new era in ulcer epidemiology characterised by equal incidence in men and women and an even distribution of lesions in the stomach and duodenum.
OBJECTIVES: To review the trends in prostate cancer (PC) incidence and mortality rates in Denmark during a 50-year period. METHODS: A population-based register study was performed of all new cases of PC recorded in the Danish Cancer Registry from 1943 to 1992. RESULTS: The age-standardized incidence rate for PC increased from 11.5/100,000 in 1943 to 1947 to 30.9/100,000 in 1988 to 1992. Age-specific incidence rates increased in all age groups over 50 years of age. Mortality rates increased from 13.5/100,000 in 1953 to 1957 to 17.8/100,000 in 1988 to 1992. No major changes in the distribution of age, stage at the time of diagnosis, or in diagnostic procedures were found, indicating that the observed change in incidence rates was not caused by attempted early detection or changes in diagnostic strategy. CONCLUSIONS: Our data suggest that the increased PC incidence observed during the period of cancer registration in Denmark represents a true increase in the number of patients with clinical PC.
OBJECTIVE: To prospectively evaluate if repeated measurements of organochlorine exposure provide a more precise measure of breast cancer risk. METHODS: In the Copenhagen City Heart Study (CCHS) participants donated blood twice, in 1976-1978 and 1981 1983. Information on breast cancer risk factors was obtained through standardized questionnaires. A cohort nested case-control study of 155 cases and 274 matched breast cancer-free controls who had participated in both CCHS examinations was conducted. The average serum organochlorine concentration over the course of the two examinations was used, testing a possible association between organochlorine exposure and breast cancer risk. RESULTS: A high serum concentration of p,p'-DDT over the course of the two examinations was associated with a more than three-fold significantly increased risk of breast cancer, and a dose-response relationship was apparent. Furthermore, the risk of breast cancer increased with increasing serum concentrations of PCB congener 118 and 138 and the total amount of DDT isomers (sigmaDDT), but the trends were not significant. CONCLUSION: This study provides new evidence of the adverse effect of some organochlorines on breast cancer risk. Furthermore, repeated assessment of exposure during a relevant time period may provide a more precise risk estimate than a single measurement.