[Alcohol drinking patterns of the Danes 1979-1992]

A questionnaire-based interview on alcohol drinking pattern in a random sample of 4,016 men and 4,179 women in 1992 was compared to an identical interview from 1979. In coherence with alcohol sale statistics, the average alcohol intake was unchanged in the population. Nevertheless, during the period drinking patterns have changed among Danes. Thus, 20 to 39 year-olds drank less, 40 to 59 years-olds drank more, fewer Danes drank during daytime, and fewer drank on weekdays at the second survey.

Trend in incidence and case fatality of meningococcal disease over 16 years in Northern Denmark

The incidence and case fatality rates of meningococcal disease were assessed in the county of Northern Jutland, Denmark, during the 16-year period from 1980 to 1995. A total of 320 patients were identified from the Meningococcal Research Database, which comprises information from the following sources: (i) the Department of Public Health, to whom notification of meningococcal disease is obligatory; (ii) the Regional Hospital Discharge Registry; and (iii) the register of the regional department of clinical microbiology. In order to assess prognostic indicators assessable at admission, information was collected for each patient from hospital records regarding contacts, symptoms and signs on arrival, laboratory data, and course of disease. The mean incidence was 4.3 cases per 100000 persons per year (range, 2.7-7.7). The incidence increased slightly during the period studied. Overall, the case fatality rate was 9.7%, with a significant rise occurring during the period (P=0.016) and a peak occurring in 1992. Advanced age (> or = 50 years), seizures, impaired consciousness, and skin bleeding on arrival at hospital were predictors of death.

Outcome of pre-hospital antibiotic treatment of meningococcal disease

OBJECTIVE

To assess the effect of pre-hospital antibiotic treatment given by general practitioners to patients with meningococcal disease.

DESIGN

A 16-year population-based historical follow-up study based on referral letters and hospital records in the County of North Jutland, Denmark.

SUBJECTS

320 patients with meningococcal disease, of whom 302 were examined by a general practitioner before admission to hospital.

MAIN OUTCOME MEASURES

Death.

RESULTS

44 patients (14.6%) were given antibiotic treatment by the referring general practitioner. Nine of these (20.5%) died, compared with 16 (6.2%) patients who did not receive pre-hospital antibiotic treatment. The presence of skin bleeding, petechiae, and impaired consciousness were strongly associated with case fatality. Even after adjustment for these variables the odds ratio (OR) for death in patients treated with antibiotics was high (OR = 3.2; 95% CI, 0.9-10.6). In the 15 patients with skin bleeding (ecchymoses, suggillations) the case fatality rate was 100% in patients treated with antibiotics, and 50% in patients who did not receive antibiotics before hospitalization. If skin bleeding was replaced in the models by the presence of disseminated intravascular coagulation on admission, the OR for death in patients with pre-hospital antibiotic treatment was 35.9 (95% CI, 2.9-441.8) in the presence of disseminated intravascular coagulation and 1.9 (95% CI, 0.2-19.5) in its absence.

CONCLUSIONS

Pre-hospital treatment is mainly given to the most severe cases with expected high case fatality, and this confounding by indication was probably not fully adjusted for with the available data. The results contradict previous findings but provide reason to doubt the benefit of pre-hospital antibiotic treatment in patients with meningococcal disease.

The risk of bacteremia in patients with monoclonal gammopathy of undetermined significance

We estimated the risk of bacteremia in patients with monoclonal gammopathy of undetermined significance (MGUS) compared with the general population; 1237 cases of MGUS were identified by linking information on detected monoclonal components in the North Jutland County with the Danish Cancer Registry. We evaluated the risk of bacteremia in the MGUS cohort during the 13-yr period from 1981 to 1993 by linkage to the Bacteremia Registry in the County. Follow-up for the occurrence of bacteremia started 30 d after detection of the M-component and continued until malignant transformation, death or until 31 December 1993, whichever came first. The expected numbers of bacteremia was based upon county, age, sex and period-specific incidence rates. The median follow-up period was 3.8 yr. Forty episodes of bacteremia occurred during 5500 person-years versus 18 expected. The crude standardized incidence ratio of bacteremia was 2.2 (95% confidence interval, 1.6-3.0). There was no distinct pattern of bacterial etiology in the MGUS cohort. Although we found an association between MGUS and risk of bacteremia, the overall risk is small and this finding hardly affects the clinical handling of MGUS patients.

Risk of colorectal cancer in relatives of patients with inflammatory bowel disease (Denmark)

OBJECTIVES

It has been suggested that inflammatory bowel disease (IBD) and colon cancer are associated because they have genetic susceptibility in common, rather than IBD causing cancer. We examined the risk of colorectal cancer in first-degree relatives of patients with IBD in order to evaluate if they share the same genetic susceptibility.

METHODS

We identified patients with IBD in the Danish Hospital Discharge Registry. A cohort of all first-degree relatives to these patients were linked to the Danish Cancer Registry. Colorectal cancers observed were compared with expected values based on age, gender, and calendar-specific incidence rates in the general population.

RESULTS

Among 4,496 patients with IBD, a total of 19,645 relatives were identified. For parents of patients with Crohn's disease, we observed 19 cases of colorectal cancer compared with 20 expected (standardized incidence ratio [SIR] = 1.0, 95 percent confidence interval [CI] = 0.6-1.5). For parents of patients with ulcerative colitis, 55 cases were observed compared with 51 expected (SIR = 1.1, CI = 0.8-1.4).

CONCLUSIONS

The study did not corroborate the hypothesis that the same genetic factors play a significant role in the etiology of colorectal cancer and IBD, but more information is needed to disregard the possible link between IBD and colon cancer.

A comparative study of scientific evaluation of abstracts submitted to the 1995 European Association for the Study of the Liver Copenhagen meeting

OBJECTIVE

Peer review is an important part of the publication of scientific results. We analysed the peer review process of abstracts submitted to the European Association for the Study of the Liver (EASL) congress in Copenhagen in 1995.

DESIGN

Comparative study. All abstracts were reviewed by all six members of the EASL scientific committee. Furthermore, each abstract was evaluated by three to six experts within 17 specific study fields, appointed by the scientific committee. All abstracts received a score on a scale from 1 to 5, one being the best. For each abstract the average was calculated for the scores of the committee members and the expert reviewers separately.

MAIN OUTCOME MEASURE

Abstract score.

RESULTS

There was a significant difference in the scores between the committee members, who scored 3.31 on average, and the expert reviewers, who scored 3.02 on average. Within most of the study fields the tendency was that the expert reviewers gave the highest scores. Moreover, there was a significant variation in the estimates among the individual reviewers as well as between the 2 groups of reviewers. Only 25% of the abstracts that received the best scores by the expert reviewers were classified in the same way by the committee members. The predictive value of a positive evaluation by the committee members was 0.6, the predictive value of a negative evaluation was 0.90.

CONCLUSIONS

There was a considerable variation in the peer review process for abstracts submitted to the 1995 EASL congress depending on selection of reviewers. Various types of peer review strategies should be tested and evaluated to secure the highest possible scientific quality of published research results.

Antibiotic therapy and outcome of monomicrobial gram-negative bacteraemia: a 3-year population-based study

Within the 3-y period 1992-94 a total of 815 episodes of monomicrobial bacteraemia caused by Enterobacteriaceae not including Salmonella were registered in the County of Northern Jutland. The 30-d case fatality rate was 24%, ranging from 21% for Enterobacter spp. (n = 43), 22% for E. coli (n = 577) to 32% for both Klebsiella spp. (n = 138) and a group of miscellaneous enterobacteria (n = 57). In 16% of the bacteraemias, antibiotic treatment was not instituted before notification of positive blood cultures; in 9% empirical antibiotic treatment was inappropriate. Antibiotic regimens mainly included beta-lactams, ampicillin or mecillinam in combination with an aminoglycoside. The following factors were independently associated with case fatality: age > or = 75 y, high comorbidity index, admission to a medical ward or an intensive care unit, nosocomial acquisition, a source of infection outside the urinary tract or an undetermined focus, Klebsiella spp., inappropriate coverage or lack of antibiotic treatment before notification of positive blood culture. It is a matter of concern that in one-sixth of patients the physicians had not responded to the possibility of bacteraemia with institution of empirical antibiotic therapy.

The risk of a diagnosis of cancer after primary deep venous thrombosis or pulmonary embolism

BACKGROUND

Several small studies have indicated an association between deep venous thrombosis or pulmonary embolism and a subsequent diagnosis of cancer, but the subject is controversial.

METHODS

We conducted a nationwide study of a cohort of patients with deep venous thrombosis or pulmonary embolism that was drawn from the Danish National Registry of Patients for the years 1977 through 1992. The occurrence of cancer in the cohort was determined by linkage to the Danish Cancer Registry. The expected number of cancer cases was estimated on the basis of national age-, sex-, and site-specific incidence rates.

RESULTS

A total of 15,348 patients with deep venous thrombosis and 11,305 patients with pulmonary embolism were identified. We observed 1737 cases of cancer in the cohort with deep venous thrombosis, as compared with 1372 expected cases (standardized incidence ratio, 1.3; 95 percent confidence interval, 1.21 to 1.33). Among the patients with pulmonary embolism, the standardized incidence ratio was 1.3, with a 95 percent confidence interval of 1.22 to 1.41. The risk was substantially elevated only during the first six months of follow-up and declined rapidly thereafter to a constant level slightly above 1.0 one year after the thrombotic event. Forty percent of the patients given a diagnosis of cancer within one year after hospitalization for thromboembolism had distant metastases at the time of the diagnosis of cancer. There were strong associations with several cancers, most pronounced for those of the pancreas, ovary, liver (primary hepatic cancer), and brain.

CONCLUSIONS

An aggressive search for a hidden cancer in a patient with a primary deep venous thrombosis or pulmonary embolism is not warranted.

Can hospital discharge diagnosis be used for surveillance of bacteremia? A data quality study of a Danish hospital discharge registry

OBJECTIVE

To assess the data quality of septicemia and sepsis registration in a hospital discharge registry in the County of Northern Jutland, Denmark.

DESIGN

Comparison of data from the discharge registry of an 880-bed, public, urban hospital in the County of Northern Jutland with data from a computerized bacteremia database at the regional department of clinical microbiology.

SETTING

Urban hospital with approximately 45,000 admissions per year.

PATIENTS

The study included 406 episodes of bacteremia in the bacteremia database and 83 discharges with the diagnosis of septicemia registered in the hospital discharge registry between January 1, 1994, and December 31, 1994.

INTERVENTIONS

None.

RESULTS

Eighteen episodes were registered in both the hospital discharge registry and the bacteremia database. Using the bacteremia database as reference standard, the sensitivity for the diagnosis of septicemia in the hospital discharge registry was 4.4% (18/406; 95% confidence intervals [CI95, 2.4%-6.4%]). By review of hospital records, we estimated the positive predictive value of septicemia registration in the hospital discharge registry as 21.7% (18/83; CI95, 12.8%-30.5%). No blood culture had been obtained in 44.4% (36/81; CI95, 33.6%-55.3%) of the cases with a discharge diagnosis of septicemia. In 33.3% (27/81; CI95, 23.1%-43.6%), the discharge diagnosis of septicemia was given, although blood cultures were negative.

CONCLUSIONS

The hospital discharge registry revealed numerous misclassifications, and the system was found not suited for surveillance of, or research in, bacteremia at present.

The cumulative incidence of venous thromboembolism during pregnancy and puerperium--an 11 year Danish population-based study of 63,300 pregnancies

OBJECTIVES

The aim of the study was to estimate the cumulative incidence of venous thromboembolism during pregnancy and the puerperium.

METHODS

All diagnoses concerning venous thromboembolism in the Hospital Discharge Registry from a Danish County in women less than 49 years of age from 1984 to 1994 were included. The number of deliveries in the County during this period was obtained from The Medical Registry of Birth.

RESULTS

The cumulative incidence of venous thromboembolism during pregnancy and puerperium was 0.85 (95% CI: 0.64-1.11) per 1000 deliveries. The cumulative incidence was 0.49 (95% CI: 0.28-04).80) in 1984-89 but increased to 1.23 (95% CI: 0.87-1.69) after the introduction of ultrasound.

CONCLUSION

The risk of diagnosed venous thromboembolism is low but estimates of the incidence are probably procedure dependent.

Biomechanical properties of normal and varicose internal spermatic veins

To investigate possible differences in biomechanical properties between varicose spermatic veins and controls. During surgery on 12 patients for grade 3 left-sided varicocele testis, 2 cm of the vein was obtained for comparison with: (i) samples of the left internal spermatic vein taken from the same anatomical localization from 8 patients without scrotal disease, and (ii) samples from the right internal spermatic vein from 7 other patients also without scrotal disease. The biomechanical properties of ring-shaped venous specimens were investigated by loading the specimen at a constant deformation rate until rupture. The relative amounts of collagen in the specimens were determined as the contents of hydroxyproline. There was a significant difference between varicocele testis/right spermatic vein in UC (unit collagen), F-max (maximum strength), Strain (ultimate extensibility) and E-fail (relative failure energy), but not in LD (diameter) and Tan-a (stiffness of the specimen). There were no significant differences between left and right spermatic vein in LD, UC, F-max, Strain, Tan-a and E-fail. There was a significant difference in LD between varicocele testis/left spermatic vein, but no relationship in UC, F-max, Strain, Tan-a and E-fail. Biomechanical analyses of the spermatic veins from patients operated for varicocele seem to support the hypothesis that a difference in biomechanical properties plays a part in the development of varicocele because a significant increase in extensibility of varicocele samples was found compared with normal right spermatic vein samples.

Risk of breast cancer in men with liver cirrhosis

OBJECTIVE

Liver cirrhosis is associated with increased levels of estrogens, which may be causally related to breast cancer. Because background estrogen levels are lower in men than in women, an estrogen-mediated link between liver cirrhosis and breast cancer would be easier to detect in men.

METHODS

Men hospitalized with liver cirrhosis in Denmark from January 1, 1977, to December 31, 1989, were followed up, through record linkage, until the end of December 1993 for the possible occurrence of breast cancer.

RESULTS

A total of 11,642 men with liver cirrhosis were identified and were followed for a mean period of 4.3 yr, for a total of 49,687 person-years. Three cases of male breast cancer were observed whereas 0.75 was expected, for a standardized incidence ratio of 4.0 (95% confidence interval, 0.8-11.7).

CONCLUSIONS

Cirrhosis, possibly via high levels of endogenous estrogens, increases the risk of breast cancer in men.

Third generation oral contraceptives and heritable thrombophilia as risk factors of non-fatal venous thromboembolism

Third generation oral contraceptives (OCs) are apparently stronger risk factors for venous thromboembolism (VTE) than other OCs, however, the increased risk may be due to confounding by indication related to differences in prescription behaviour. We estimated the risk of VTE associated with use of OCs with and without the presence of Factor V Leiden mutation, protein C-, protein S- or antithrombin deficiency. Sixty-seven cases with VTE were compared with 134 controls. The risk of VTE in the presence of thrombophilia was of the same magnitude for third generation OC users as for users of other OCs; OR: 52.5 (95% CI: 3.7-738.1) and OR: 63.3 (95% CI: 6.2-648.4), respectively. It is unlikely that confounding by indication entirely explains the risk of VTE associated with third generation OCs since the combined effect exceeds what could be explained if this source of error was the only determinant of the association.

Short Communication - Continued increase in prevalence of obesity in Danish young men

BACKGROUND

Previous studies of Danish young men showed a steep increase of obesity since the birth years of the early 1940s with a levelling off in the 1950s.

OBJECTIVE

To study the current prevalence of obesity and its recent changes in Danish young men.

DESIGN

Cross-sectional study based on weight and height measured at the military board for the birth cohorts 1955, 1965 and 1973-75.

SUBJECTS

We obtained information from the old paper files comprising the two cohorts of men born in 1955 (6549 adults) and 1965 (6404 adults) and prospectively examined 4300 from the birth cohorts 1973-75 in a conscription district in Denmark during the period 1 August 1993 to 31 July 1994.

RESULTS

The prevalence of obesity (defined as body mass index (BMI) > or = 30 kg/m2) was 1.5% in 1955, 2.1% in 1965 and 4.6% in 1973-75 birth cohorts. The median BMI has increased during the period from 21.7-22.8 kg/m2.

CONCLUSION

Obesity is relatively common and has increased among Danish young men.

Major haemorrhagic complications during oral anticoagulant therapy in a Danish population-based cohort

OBJECTIVES

To estimate the incidence of bleeding leading to death or hospital admission in out-patients treated with oral anticoagulants.

DESIGN

Population-based historical cohort study 1 January 1992 to 31 September 1994.

SETTING

The County of North Jutland, Denmark (488,000 inhabitants).

SUBJECTS

Six hundred and eighty-two consecutive patients commencing oral anticoagulant therapy.

MAIN OUTCOME MEASURES

Fatal bleeding or bleeding demanding hospital admission.

RESULTS

In 756 treatment-years of follow-up, there were 45 major haemorrhagic events (6.0 per 100 treatment-years) in 42 patients, of which seven (0.9 per 100 treatment-years) were fatal. The risk of a first major haemorrhagic episode was highest during the first 90 days of treatment compared with duration above one year (incidence rate ratio, IRR, 1.9; 95% CI, 0.8-4.1). The rate was highest above the age of 60 years, 6.8 per 100 treatment-years, compared with 2.9 per 100 treatment-years below 60 years (IRR 2.3; 95% CI, 1.0-5.6). The rate for a bleeding event was slightly higher in females than in males (IRR 1.3; 95% CI, 0.7-2.3), but did not vary according to type of anticoagulant drug.

CONCLUSIONS

The reported rates of major bleeding in this routine community setting implied a higher bleeding risk than was found in randomized trials or when patients are monitored in specialist anticoagulation clinics.

High prescribers of antibiotics among general practitioners--relation to prescribing habits of other drugs and use of microbiological diagnostics

General practitioners' (GPs') prescriptions of antibiotics have shown large variations and may not always be rational. We analysed GPs' prescriptions and use of microbiological diagnostics in Viborg County during a 6-month period in 1992 based on Danish Health Service data. In a logistic regression model we tried to identify potential predictors for a high prescriber of antibiotics, i.e. the GPs with the highest number of prescriptions per patient (upper quartile). Two categories were calculated for the predictor variables, dividing the distribution by the median value. The most liberal GP wrote 15 times as many prescriptions for antibiotics per patient as the most restrictive GP. A strong predictor for high prescribing of antibiotics was the number of prescriptions for other drugs per patient [odds ratio (OR) 12.3, 95% CI: 2.8-54.4] after adjustment for age and sex. High use of throat swabs was a strong negative predictor of high prescribing of antibiotics (OR 0.2, 95% CI: 0.1-0.8) while high use of cultures (OR 2.4, 95% CI: 0.8-6.9) and of urinary susceptibility tests (OR 3.1, 95% CI: 1.1-9.3) were positive predictors. The GP's general attitude to pharmacotherapy seems important for antimicrobial chemotherapy, and if use of antibiotics should be reduced, targeted strategies should be aimed at high prescribers.

The Danish strong analgesic surveillance system

The legal consumption of strong analgesics is increasing and research addressing the complex consequences of this expansion is needed. We describe the Danish strong analgesic surveillance system comprising copies of all prescriptions of strong analgesics purchased at Danish pharmacies. The system is operated by the Public Health officers and has been computerized since 1993. In addition to specific informations about the drugs in question the system comprises personal registration numbers (CPR) of both patients and doctors issuing the prescription. The system therefore allows: 1) a precise and valid identification of the individuals purchasing and prescribing strong analgesics, 2) an option to describe possible changes in consumption over time, and 3) the possibility of a highly reliable record linkage with other Danish population-based data sources. Validation studies are reported and strengths and limitations of the system are discussed.