Do preventive child examinations in general practice reduce the risk of overweight and obesity?

Background

The prevalence of children with overweight and obesity is increasing. General practitioners in Denmark follow children throughout early childhood via the preventive child health examinations. These examinations are offered to all children from birth to the age of five. Thus, the general practitioners have a unique opportunity for early tracing and identification of overweight and obesity, but the impact of the examinations are not examined. Therefore, the aim of this study was to examine the association between attending preventive child health examinations and the risk of overweight and obesity at the age of six both for the total pediatric population and within groups of vulnerable children such as children of parents with low educational level or low household income.

Methods

A population-based birth cohort study was conducted including all Danish children born from 2000-2012 using the Danish nationwide registers. Data included information on child participation in preventive health examinations at general practice, height and weight at the age of six, and parental information on socioeconomic factors.

Results

The analyses included 801,444 children. Attending preventive child health examinations were not associated with a lower risk of overweight at the age of six. A lower risk of obesity was seen in children attending the examinations, both in the general population (RR 0.71, 95% CI 0.66-0.76) and within vulnerable groups (low level of maternal education: RR 0.80, 95% CI 0.72-0.89), low household income (RR 0.79, 95% CI 0.72-0.87). The risk of obesity was greater in the vulnerable groups than in the not-vulnerable groups.

Conclusions

Attending preventive child health examinations were associated with a lower risk of obesity at the age of six, but not overweight. This was seen for both the general pediatric population and within vulnerable groups. The lowest risk of obesity was seen in the not-vulnerable groups.

Key messages

• The results indicated that attending preventive child health examinations in general practice reduced the risk of obesity at the age of six, but not the risk of overweight.

• The lowest risk of obesity was seen in the not-vulnerable groups attending the preventive child health examinations in general practice.

Inflammatory bowel disease at a young age – implications for achieving upper secondary education

Background

The incidence of inflammatory bowel disease (IBD) among children and adolescence is increasing worldwide. Having a chronic condition at a young age may affect educational achievement and later employment and self-support. The study aims to examine the impact of being diagnosed with IBD before 18 years of age on achieving an upper secondary education before 25 years of age.

Methods

Using the Danish National Patient Register (1980-2018) all patients (born 1970-1994) diagnosed with IBD at a young age (<18 years) were identified. The IBD-patients were matched on age and sex with 10 references without IBD at the index date (date of diagnosis of IBD). The outcome was achieving an upper secondary education using data from Danish Education Registers. The association between IBD diagnosis and achieving an upper secondary education was analyzed using Cox regression with robust variance estimation adjusting for parents’ highest educational level. Furthermore, stratified analyses were performed on parental socioeconomic status (education and income).

Results

We identified 3,178 patients with IBD: Crohn’s disease (CD) n = 1,344, Ulcerative colitis (UC) n = 1,834. Reference n = 28,220. The median age at diagnosis was 15.3 years (IQR: [13.0;16.9]). At the age of 25 74.0% (CI: 71.6-76.4) for CD, 75.8% (CI: 73.8-77.8) for UC, and 69.7% (CI: 69.2-70.3) for references had achieved an upper secondary education. The adjusted Hazard ratio (HR) of achieving an upper secondary education was 1.05 (CI: 1.00 -1.11) for CD and 1.09 (CI: 1.04 -1.15) for UC. When stratifying the IBD-patient with the lowest socioeconomic status performed better than their peers.

Conclusions

Being diagnosed with IBD before 18 years of age did not reduce the chance of achieving an upper secondary education. Patients with low socioeconomic status performed better than their peers, however the study gives no explanation of this.

Key messages

• Children diagnosed with IBD before 18 years of age had at least the same chance of achieving an upper secondary education compared to references.

• IBD patients with low social economic status performed better than their peers.

The impact of parental mental health and socioeconomic position on child preschool health

Background

Many children, approximately one out of four to five, live in families with parental mental health problems. Knowledge on the impact of other mental health problems than depression or anxiety is sparse as well as the impact of the father. Therefore, we aimed to examine the effect of maternal and paternal mental health on child respiratory illness.

Methods

A population-based birth cohort study was conducted including all Danish children born from 2000-2012 using the Danish nationwide registers. Two follow-up periods were created: From age 1-2 and age 3-5. Mental health was categorised in three: No mental health problems, minor mental health condition if handled in solely primary healthcare; and moderate-severe if handled in psychiatric healthcare settings. Child respiratory illness was identified by prescribed medication or hospital-based diagnoses. Incidence rate ratios (IRR) were calculated using Poisson regression analysis.

Results

The analyses included 810,243 children. 26% of the mothers and 17% of the fathers were classified with mental health conditions. Children of parents with mental health conditions were more likely to have respiratory illness (10-12% vs. 7.7%). Adjusted IRRs revealed higher risks for children of mothers with minor (IRR 1.32 (CI95% 1.30-1.34)) and moderate-severe mental health conditions (IRR 1.48 (CI95% 1.44-1.51)). For paternal mental health, the IRRs were 1.14 (CI95% 1.12-1.16) for minor and IRR 1.14 (CI95% 1.11-1.17) for moderate-severe mental health conditions. The IRRs were a little higher for the children aged 1-2 years compared to 3-5-years.

Conclusions

Children of parents with mental health conditions were at greater risk of respiratory illness. This was evident for the mental health of both parents, most pronounced for the mother. Not only moderate-severe, but also minor mental health conditions increased the risk of respiratory illness.

The risk of preterm birth in combinations of mental disorder and socioeconomic position among Danish women

Background

Inequality in preterm birth is a public health challenge requiring identification of pregnant women at particularly high risk of preterm birth. Therefore, the aim was to estimate the risk of preterm birth in women with different combinations of mental health conditions and socioeconomic position.

Methods

Based on Danish registries, we conducted a nationwide cohort study including all first-time mothers giving birth to a singleton liveborn infant in Denmark between 2000 through 2016. We examined the risk of preterm birth (<37 weeks of gestation) in different combinations of mental health conditions (no, minor, and moderate/severe) and educational level (high, intermediate, and low) in three age strata (<25, 25-30, and >30 years). The relative risk of preterm birth was estimated using Poisson regression with a robust error variance. We measured the attributable proportion to assess additive interaction between the effects of exposures.

Results

Of the 415,523 included first time mothers, 29,069 (7,0%) gave birth preterm. The risk of preterm birth increased in combinations of higher degree of mental health conditions, lower degree of educational level, and increasing age. Women aged>30 years with moderate/severe mental health conditions and low educational level had the highest risk of preterm birth (13.7%). The analysis of additive interaction revealed only a limited additional effect of being exposed to mental health conditions and lower educational levels in each age strata. However, positive additive interaction was found between age>30 year and combinations of mental health conditions and educational level.

Conclusions

Substantial inequality in preterm birth remains with increasing risk in women with combinations of higher degree of mental health conditions and lower degree of educational level. In the prevention of inequality in preterm birth special attention on women aged>30 years exposed to mental health conditions and lower educational levels is essential

Impact of maternal mental health problems on perinatal outcomes for the infant

Background

Mounting evidence suggests that mental health problems in pregnant women may negatively affect the intra- and extrauterine health and development of the child. This is especially of concern as the prevalence of mental health problems in pregnant women is high and believed to be increasing. We set out to quantify the effect of maternal mental health status on the risk of adverse perinatal outcomes for the infant.

Methods

We undertook a nationwide register-based cohort study including children born alive in Denmark between 2000 and 2016. The exposed cohort was children born to mothers with mental health problems in the two years prior to childbirth that had been cared for in primary care settings only (Group 1, minor problems, n = 71 759) or had required psychiatric intervention (Group 2, moderate-severe problems, n = 41 099). All non-exposed children served as comparison group (n = 908 268). We calculated risk ratios (RRs) with 95% confidence intervals (CI) for each perinatal outcome of interest.

Results

Infants in Group 1 as well as Group 2 were at higher risk of neonatal death than infants born to unaffected mothers, although for Group 2 the trend was non-significant (Group 1: adjusted RR (aRR) 1.34, 95% CI 1.17-1.52; Group 2: aRR 1.11, 95% CI 0.94-1.32). Both exposure groups were furthermore at significantly increased risk of 5-minute Apgar scores <7 (Group 1: aRR 1.27, 95% CI 1.17-1.37; Group 2: aRR 1.52, 95% CI 0.94-1.32) and <4 (Group 1: aRR 1.26, 95% CI 1.10-1.44; Group 2: aRR 1.28, 95% CI 1.08-1.52) and of hospital admission in the neonatal period (Group 1: aRR 1.22, 95% CI 1.19-1.24; Group 2: 1.29, 95% CI 1.26-1.32), paralleled by a significantly higher risk of preterm birth and several neonatal morbidities.

Conclusions

Infants born to mothers with moderate-severe as well as minor mental health problems were at increased risk of multiple adverse perinatal outcomes, thus calling for effective preventive strategies to improve outcomes in both groups.

The effect of breast cancer on work participation in different sectors. A Danish registry based study

Background

A breast cancer diagnosis affects an individual’s affiliation to the labor market, but whether the effect of breast cancer variates in different sectors in a Danish setting has not been examined. The present study investigated the effect of stage IA breast cancer (tumor<20 mm and no lymph nodes involved in six sectors among Danish women being part of the work force. Stage IA breast cancer has a good prognosis, and it would be assumed that the majority have returned to work after 1 year.

Methods

This registry-based cohort study was based on data from linked Danish nationwide registries. We identified 5,543 women (aged 25-63 years) diagnosed with breast cancer (BC) stage IA (exposed) and 65.889 women without breast cancer (unexposed) and included women from the different sectors. We calculated a yearly Work Participation Score (WPS), defined as the proportion of weeks being self-supported during a year. We compared the means of WPS for exposed and unexposed women in six different sectors: 1) teaching, 2) childcare, 3) eldercare, 4) cleaning, 5) administration and 6) hospitality industry.

Results

BC had a negative effect on being self-supporting for women in all six sectors in all three years, although the effect declined. In the first year, the difference in WPS varied between 0.38 and 0.54. During the second year all BC patients had still significantly lower WPS with the largest difference in hospitality industry (0.65 (95% CI 0.50-0.80) for exposed women and 0.86 (95% CI 0.83-0.88) for unexposed women). In the third year, the effect further declined although WPS was still significantly lower for most sectors with the biggest difference in the cleaning sector.

Conclusions

A stage IA BC diagnosis had a negative effect on being self-supportive after 2 and 3 years among women in all six sectors, although the difference was largest among cleaning workers. This may indicate, that individual follow-up in relation to work participation is necessary.

Key messages

Although breast cancer stage IA has a good prognosis, it still affects being self-supporting after three years. A diagnosis of breast cancer affects the affiliation to the labour market, but the effect differs according to different sectors.

Parental mental vulnerability and use of healthcare services in infants

Background

Parental mental illness has been associated with a number of consequences for the health and use of healthcare services of the child. However, most research has focused on maternal depression. Research examining the impact of paternal mental vulnerability (MV) as well as different degrees of MV are needed to plan interventions. Therefore, the aim of this study was to examine the association between different categories of individual and combined parental MV and the child’s use of healthcare services the first year of life.

Methods

A population-based birth cohort study was conducted including all Danish children born from 2000-2016 using the Danish national registers. Exposure was parental MV of three categories according to the degree of MV: Group 1 “minor MV” with mental related contacts to primary healthcare and/or prescribed psychopharmaceuticals, group 2 “moderate MV” and group 3 “severe MV” both with contacts to psychiatric hospital. Outcome was contacts to GP the first year of life expressed as incidence-rate ratios (IRR) using Poission’s regression analyses.

Results

The analyses included 952,709 children. 21% of the mothers and 11% of the fathers were in the MV groups. Parental MV (any parent, any MV-group) was associated with an increased risk of GP contacts daytime and out-of-hour contacts. If both parents were classified as group 1 MV, IRR were 1.21 (CI95 1.20-1.22). IRR were 1.18 (1.17-1.18) resp. IRR 1.05 (1.04-1.06) if only the mother resp. father were in MV group 1. The same pattern were seen for out-of-hour contacts; IRR 1.28 (1.26-1.31) for both parents in group 1 and IRR 1.19 (1.18-1.20) resp. IRR 1.09 (1.08-1.11) for the mother resp. father.

Conclusions

Maternal and paternal MV were associated with an increased risk of GP contacts daytime and out-of-hour contacts although maternal MV had the highest risk. Even minor MV had an impact on healthcare contacts and the risk increased further if both parents were classified as minor MV.

Key messages

Both maternal and paternal mental vulnerability has an impact on the child’s healthcare contacts. Our results indicate the need for a focus also on minor mental vulnerability in the planning of interventions.

Socioeconomic consequences for adults with atrial septal defect: A register based follow-up study

Background

Atrial Septal Defect (ASD) is considered one of the most benign defects among congenital heart disease. The very good short and midterm outcomes after closure in the recent decades has led to believe that the ASD population is almost comparable to the background population after treatment. However, recent studies indicate that these patients are much more affected by their disease than first assumed. In this nationwide cohort study, we report the first long-term follow-up of use of permanent social security benefits and work participation in adults with ASD.

Methods

All Danish patients born before 1994 and diagnosed with ASD between 1959-2013 (n = 2,277) were identified from the Danish registries. A comparison cohort was created using the Danish Civil Registration System, matching every verified ASD patient with 10 persons from the general population on gender and birth year. We used Cox proportional hazards regression to compare the risk of receiving permanent social security benefits in the ASD patients compared with the matched cohort. Using the DREAM database we calculated the proportion of patients and controls not working at the age of 30 years.

Results

ASD patients had a higher risk of receiving permanent social security benefits (hazard ratio 2.3 (95% confidence interval 2.1-2.6)) compared with the comparison cohort; 24% of the ASD patients was receiving permanent social security benefits at the end of follow up compared with 12% of the comparison cohort. At the age of 30 years, the proportion not working was 28% in the ASD cohort and 18% in the comparison cohort. Of patients not working 23% had a psychiatric diagnose compared to 6.8% of the controls.

Conclusions

The risk of receiving permanent social security benefits was twice as high in patients with ASD and the work participation was reduced compared with the background population.

Key messages

The poor affiliation to the work force and high prevalence of psychiatric morbidity is worrying. It demands for an increased psychosocial support by professionals caring for patients with ASD.

Predictors of a high work participation in the flexi-job scheme: a regional Danish cohort study

Background

In Denmark, people with permanent and significant reduced work capacity can be assigned to a flexi-job (FJ) scheme. In 2013, the social security policy for FJ was reformed in order to improve the chances for employment for people with reduced work capacity. In a Danish cohort study from the North Denmark Region we aimed to describe work participation in the flexi-job scheme before and after the reform. Furthermore, we described the associations between employment in the flexi-job scheme and predictors such as sociodemographic factors, healthcare use, and work participation before assignment.

Methods

The study population included individuals assigned to the FJ scheme between 2010 and 2015 in the North Denmark Region. The study population was followed until leaving the FJ scheme or end of follow up (September 2017). Baseline information included data on sex, age, place of residence, number of contacts to specialized healthcare, and number of working weeks five years before. Work participation score (WPS) was defined as number of working weeks divided with the total number of weeks in the FJ scheme. High WPS was defined as above the median. We used a logistic regression model to study associations between baseline characteristics and high WPS.

Results

A total of 4,668 people were included in the study. The overall median WPS were 73% (interquartile range (IQR) 42% - 90%). Policy changes (OR 1.40, 95% confidence interval (CI ): 1.24 - 1.59), male sex (OR 1.16, CI:1.03 - 1.31), young age (OR 1.45, CI: 1.17 - 1.80), urban living (OR 1.22, CI:1.03 - 1.46), no contact to specialized healthcare (OR 1.54, CI: 1.21 - 1.99), and a strong association to the labor market before awarded FJ (OR 4.25, CI: 3.34 - 5.41) were all predictors of a high WPS during FJ-scheme.

Conclusions

Policy changes increased work participation in the FJ-scheme. However, the strongest predictor of a high WPS for people awarded FJ was the degree of work participation before the scheme.

Key messages

Several factors had impact on work participation in a flexi-job scheme. The flexi-job scheme might be insufficient to secure employment for people with prior weak affiliation to the labor market.

Agreement between medical expert assessments in social medicine

BACKGROUND AND AIMS

Medical specialists in social medicine play an important role in description of work-related health problems of the individual citizen in the Municipalities, yet knowledge of the consistency in their medical assessment remains poor. However, we expect good agreement between medical specialists' descriptions of health and work ability. The present paper aims to evaluate inter-rater differences between assessments issued by medical specialists in social medicine on health-related work ability in patients with musculoskeletal diseases and some lighter psychiatric diseases.

METHODS

A total of 11 medical specialists in social medicine from four departments across Denmark each described eight subjects' health and health-related disability upon request from the municipal authorities. The resultant 88 written medical expert assessments were evaluated and scored independently by two medical specialists in social medicine with respect to functional impairment/ health-related work ability as intact, slightly reduced, much reduced, or extremely reduced. Kappa analysis described the inter-rater agreements.

RESULTS

The combined Kappa value for work ability was 0.33 (slight agreement). In the category ''extremely reduced'' work ability the Kappa value was 0.61 (good agreement), but mostly this result was due to one subject. One department had better intra-departmental agreement than the other departments. Agreement on the level of work ability was poorer in subjects with psychiatric diseases.

CONCLUSIONS

The assessments from medical specialists in social medicine on work ability and thereby occupational possibilities show much variation. The results of the present study demonstrate that there is much room for improving agreement on these assessments.

Non-calculus suppurative cholangitis in Danish patients with inflammatory bowel disease

BACKGROUND/AIMS

We examined the risk of non-calculus suppurative cholangitis in patients with inflammatory bowel disease in the entire Danish population.

METHODOLOGY

The study included all patients discharged from Danish hospitals with a diagnosis of Crohn's disease or ulcerative colitis as registered in the Danish National Registry of Patients from January 1, 1977 to December 31, 1992. We compared the observed number of patients hospitalized with suppurative cholangitis with expected numbers on the basis of age, gender, and calendar-specific incidence rates in the general population.

RESULTS

Overall, 15,317 eligible patients with inflammatory bowel disease were discharged during the study period. Among these were 52 cases of non-calculus suppurative cholangitis. The incidence rate of non-calculus suppurative cholangitis in the cohort with inflammatory bowel disease was 46.1 per 100,000 person-years. The standardized incidence ratio (SIR) for suppurative cholangitis was increased similarly for patients with Crohn's disease [SIR=6.7, 95% confidence interval (CI): 3.1-12.7] and for patients with ulcerative colitis (SIR=6.6, 95% CI: 4.7-9.1). The highest relative risk was found in male patients younger than 40 years of age, for both Crohn's disease and ulcerative colitis (SIR=70.5 and 78.7, respectively).

CONCLUSIONS

Patients with inflammatory bowel disease have an increased risk of non-calculus suppurative cholangitis.

Azathioprine, mercaptopurine and birth outcome: a population-based cohort study

BACKGROUND

Data on the safety of azathioprine and mercaptopurine during pregnancy are very sparse.

AIM

To examine the risk of adverse birth outcomes in women who took up prescriptions for azathioprine or mercaptopurine during pregnancy.

METHODS

This is a Danish cohort study based on data from a population-based prescription registry, the Danish Birth Registry and the Hospital Discharge Registry. To examine the risk of congenital malformations, we included nine pregnancies exposed 30 days before conception or during the first trimester. To examine perinatal mortality, pre-term birth and low birth weight, we included 10 pregnancies exposed during the entire pregnancy. Eleven different exposed women were included in the study. Outcomes were compared with those of 19 418 pregnancies in which no drugs were prescribed to the mothers.

RESULTS

Fifty-five per cent of the exposed women had inflammatory bowel disease and 45% other diseases. Adjusted odds ratios for congenital malformations, perinatal mortality, pre-term birth and low birth weight were 6.7 (95% confidence interval, 1.4-32.4), 20.0 (2.5-161.4), 6.6 (1.7-25.9) and 3.8 (0.4-33.3), respectively.

CONCLUSIONS

Our results suggest that there is an increased risk of congenital malformations, perinatal mortality and pre-term birth in children born to women treated with azathioprine or mercaptopurine during pregnancy. More data are needed to determine whether the associations are causal or occur through confounding.

Birth outcome in women exposed to 5-aminosalicylic acid during pregnancy: a Danish cohort study

BACKGROUND

5-Aminosalicylic acid (5-ASA) preparations are the firstline drugs in the treatment of inflammatory bowel disease. Data on the safety of these drugs in pregnancy are sparse.

AIMS

To examine the risk of adverse birth outcome in women who were prescribed 5-ASA drugs during pregnancy.

PATIENTS

Women were included in the study if they were prescribed 5-ASA drugs immediately before or during pregnancy. To examine the risk of malformations, we included 60 pregnancies exposed to 5-ASA drugs 30 days before pregnancy or in the first trimester. To examine stillbirths, preterm births, and low birth weight, we included 88 pregnancies exposed during the entire pregnancy. Outcomes were compared with those of 19 418 pregnancies in which no drugs were prescribed for mothers during the study period.

METHODS

We conducted a Danish cohort study based on data from a population based prescription registry, the Danish Birth Registry, and the Hospital Discharge Registry in North Jutland County.

RESULTS

Odds ratios for malformations, stillbirth, preterm birth, and low birth weight in women who received prescriptions for 5-ASA drugs were 1.9 (95% confidence interval 0.7-5.4), 6.4 (1.7-24.9), 1.9 (0.9-3.9), and 1.2 (0.4-3.3), respectively. The increased risk of stillbirth and preterm birth were found only in patients with ulcerative colitis.

CONCLUSIONS

We found an increased risk of stillbirth and preterm birth in women who had been prescribed 5-ASA drugs during pregnancy but no substantial increased risk of malformations. It was difficult to distinguish the specific effects of disease activity and 5-ASA drugs.

A comparative analysis of different methods for obtaining estimates of alcohol consumption in a Danish population survey

AIMS

The aim of the present study was to compare different measures of alcohol consumption used in a Danish survey.

METHODS

A stratified random sample was extracted from the Civil Registration System. From January 1997 to January 1998 approximately 8 telephone interviews were conducted every day, including Sundays and holidays, ending with a total of 3,050 interviews after 1 year. Two main approaches to measure alcohol consumption were used: the quantity-frequency and the recent occasion approaches; the latter is subdivided into previous week and previous day approaches.

RESULTS

The overall estimated number of units (= 12 g of pure alcohol) per week was 6.8 (95% confidence intervals (CI): 6.5-7.1), 6.7 (95% CI: 6.4-7.1) and 8.5 (95% CI: 7.8-9.1) for the quantity-frequency, previous week and previous day approaches, respectively. A total of 50% of the men and 70% of the women did not drink alcohol the previous day. Among people classified as high consumers in the previous week and previous day approaches, less than 60% and 30%, respectively, were similarly classified in the quantity-frequency approach.

CONCLUSION

There was agreement on the level of alcohol consumption between the quantity-frequency and previous week approaches, but higher estimates when using the previous day approach. The previous day approach varied more in relation to the interview day and season compared with the quantity-frequency approach and the previous week approach. The recent occasions approach showed some difficulties in classifying the individuals. If the alcohol consumption is included in a model as a risk indicator or a confounder, the quantity-frequency approach would be more preferable than the recent occasion approach.

Episodic heavy drinking in four Nordic countries: a comparative survey

AIMS

The purpose of this study was to compare the phenomenon of episodic heavy drinking (binge drinking) and its different indicators in the Nordic countries.

DESIGN

A comparative survey of four Nordic countries.

SETTING

Telephone interviews in Denmark, 1997; Finland, 1996; Norway, 1996; and Sweden 1996-97.

PARTICIPANTS

Random samples of men and women aged 19-71 years.

MEASUREMENTS

Episodic heavy drinking was measured by the frequency of subjective intoxication, of drinking six or more drinks at a time (6+), and of negative consequences (mainly hangover symptoms). Additionally, annual consumption and measures of intake per occasion were used.

FINDINGS

Annual consumption, overall frequency of drinking and frequency of drinking 6+ were highest in Denmark and lowest in Norway. Frequency of subjectively defined intoxication was highest in Finland. There it was clearly higher than the frequency of drinking 6+, whereas in Denmark the contrary was observed. Finnish and Norwegian men and Danish women reported the largest quantities drunk per occasion. Results on 6+ frequency and the prevalence of negative consequences, with annual consumption held constant, suggest that Danes have the least concentrated drinking pattern. With annual consumption held constant, Norwegians report as high a frequency of intoxication, as do Finns.

CONCLUSIONS

The relations between subjective and more objective measures of episodic heavy drinking vary considerably between the Nordic countries. The results suggest that the definition, acceptability and experience of intoxication vary even when a set of relatively homogeneous countries are compared.

Use of lipid-lowering drugs during 1991-98 in Northern Jutland, Denmark

AIMS

To examine a) the use of lipid-lowering drugs in North Jutland County in Denmark from 1991 to 1998 and b) the pattern of usage according to sex and age.

METHODS AND RESULTS

We used the Pharmaco-Epidemiological Prescription Database in the county to identify all reimbursed prescriptions for lipid-lowering therapy from 1991 to 1998. One-year incidence rates (IR) and prevalence (P) of the use of lipid-lowering drugs were calculated. Both IR and P of patients in lipid-lowering therapy were stable until 1994, with the IR below 100 per 100 000 for both sexes. The IR then increased from 59.9 to 236.5 per 100 000 person-years in 1998 for women, and from 88.6 to 322.8 per 100 000 person-years for men. The utilization patterns were identical between the sexes. Thus, in both women and men the highest prevalence and incidence rates of lipid-lowering drug therapy were seen in the 60-69-year-olds. Furthermore, the marked increase in both prevalence and incidence of persons on lipid-lowering drug therapy between 1994 and 1998 was the result of an increased number of prescriptions in the 50-59, 60-69 and 70 + years olds, in both women and men. There was a remarkable 4-5 fold increase in the numbers of new patients who received statins during the same period.

CONCLUSIONS

The overall use of lipid-lowering drugs has increased markedly over the last few years in Northern Jutland, Denmark. The increase began following publication of the first major trial documenting the benefit of therapy with statins.

Birth outcomes of women with ulcerative colitis: a nationwide Danish cohort study

OBJECTIVE

Our study aimed to compare the birth outcomes in offspring of women with ulcerative colitis with controls without the disease.

METHODS

A cohort study of 1531 newborns to mothers with ulcerative colitis, and 9092 controls, based on linkage between the Danish National Registry of Patients and the Danish Birth Registry from 1982 to 1992.

RESULTS

Among the births to women with ulcerative colitis, 569 took place before and 962 after the first hospitalization for ulcerative colitis. We found no increased risk of either low birth weight or intrauterine growth retardation for newborns born before or after the mothers' first hospitalization. The risk of preterm birth was increased when birth occurred after the mothers' first hospitalization (odds ratio = 1.4, 95% confidence interval = 1.1-1.9), and particularly when the first hospitalization for ulcerative colitis took place during pregnancy (odds ratio = 3.4, 95% confidence interval = 1.8-6.4).

CONCLUSIONS

In the offspring of women with ulcerative colitis, we found no increased risk of low birth weight or signs of intrauterine growth retardation. The risk of preterm birth was increased in the offspring of women with ulcerative colitis, particularly when the first hospitalization for ulcerative colitis occurred during pregnancy.

Birth outcomes in women exposed to anticonvulsant drugs

OBJECTIVES

To examine the risk of malformations and fetal growth in women treated with anticonvulsant drugs in North Jutland County, Denmark.

MATERIAL AND METHODS

All women treated with anticonvulsant drugs in the county were identified in a Pharmaco-Epidemiological Prescription Database and linked to the Danish Medical Birth Registry and the Regional Hospital Discharge Registry.

RESULTS

We identified 235 pregnancies exposed to anticonvulsants around conception and/or during pregnancy as well as 17,259 unexposed pregnancies where the mother had not received any prescription. There was 1 case of neural tube defect among 15 malformations in the exposed cohort. The overall risk of malformations was 2.2 (95% confidence intervals 1.3-3.8). The risk of low birth weight and preterm delivery was 1.5 (95% confidence intervals 0.6-3.7) and 1.6 (95% confidence intervals 1.0-2.5), respectively.

CONCLUSION

We found an increased risk of congenital malformations and a tendency to growth retardation in children of women exposed to anticonvulsants.

Risk of ulcerative colitis and Crohn's disease among offspring of patients with chronic inflammatory bowel disease

OBJECTIVE

The incidence of inflammatory bowel disease (IBD) varies among and within countries, but several studies have indicated that genetic factors may play an important role in the etiology of IBD. A Danish regional study has observed an almost 10-fold increased risk for ulcerative colitis (UC) and Crohn's disease (CD) among first-degree relatives of patients with these diseases. To give more precise risk estimates we conducted a nationwide study using population-based data from the Danish National Registry of Patients (NRP).

METHODS

All patients from the entire Danish population (5.2 million), who were discharged between 1977 and 1992 with a diagnosis of either UC or CD were extracted from the NRP. The offspring of these patients born in 1958 or later were identified in the Civil Registration System and subsequently linked to the NRP by means of the civil registration number. All Danish citizens alive or born on April 1, 1968 or later are registered in the Civil Registration System by a unique registration number, which includes the data of birth and links the offspring to their parents. The prevalence proportion ratio (PPR) was estimated by dividing the observed number of offspring with UC or CD, respectively, with the expected number of cases from the general population.

RESULTS

The PPRs of CD and UC among offspring of patients with UC were 2.6 and 5.1, respectively, and the PPRs of CD and UC among offspring of patients with CD were 12.8 and 4.0, respectively. All ratios were significantly increased.

CONCLUSION

The risk for UC and CD among offspring of patients with IBD is 2-13 times higher than the risk within the general population.

Birth outcomes of women with celiac disease: a nationwide historical cohort study

OBJECTIVE

We aimed to examine birthweight, low birthweight (<2500 g), and intrauterine growth retardation in offspring of women with celiac disease in relation to their first hospitalization for the disease.

METHODS

This was a historical cohort study based on The Danish Medical Birth Registry data of celiac women discharged from Danish hospitals from 1977-1992. The study included 211 newborns to 127 mothers with celiac disease, and 1260 control deliveries.

RESULTS

Before celiac women were first hospitalized the mean birthweight of their newborns was 238 g (95% confidence interval [95% CI] = 150, 325 g) lower than that of the control women, after adjustment for potential confounders. After the first hospitalization the mean birthweight for newborns of diseased women was higher than that of controls, by 67 g (95% CI = -88, 223 g) after adjustment for potential confounders. Before celiac women were first hospitalized we found an increased risk of low birthweight (odds ratio [OR] = 2.6, 95% CI = 1.3-5.5) and intrauterine growth retardation (OR = 3.4, 95% CI = 1.6-7.2). After celiac women were first hospitalized we found no increased risk of low birthweight and no babies with intrauterine growth retardation.

CONCLUSIONS

Offspring of mothers with celiac disease had lower birthweight than expected and more than a three-fold higher risk of intrauterine growth retardation when birth occurred before the first hospitalization for the disease. After the mother's first hospitalization the birthweight was similar to controls and no increased risk of low birthweight was seen. Our study indicates that treatment of celiac women is important in the prevention of fetal growth retardation.

Risk of primary biliary liver cirrhosis in patients with coeliac disease: Danish and Swedish cohort data

BACKGROUND

Several case reports, but only a few studies, have examined the coexistence of coeliac disease and primary biliary cirrhosis.

AIM

To estimate the risk of primary biliary cirrhosis in two national cohorts of patients with coeliac disease in Denmark and Sweden.

METHODS

Through record linkage all Danish patients hospitalised with coeliac disease were followed for possible occurrence of primary biliary cirrhosis from 1 January 1977 until 31 December 1992. All patients hospitalised with coeliac disease in Sweden from 1987 to 1996 were also followed in a separate analysis.

RESULTS

A total of 896 patients with coeliac disease were identified in Denmark with a median follow up period of 9.1 years for a total of 8040 person-years at risk. Two cases of primary biliary cirrhosis were observed where 0.07 were expected, giving a standardised incidence ratio of 27.6 (95% confidence interval 2.9 to 133.5). A total of 7735 patients with coeliac disease were identified in Sweden with a median follow up period of 5.1 years for a total of 39 284 person-years at risk. Twenty two people with primary biliary cirrhosis were identified compared with 0.88 expected, giving a standardised incidence ratio of 25.1 (95% confidence interval 15.7 to 37.9).

CONCLUSION

Patients with coeliac disease are at increased risk of having primary biliary cirrhosis.

Risk of acute pancreatitis in patients with chronic inflammatory bowel disease. A Danish 16-year nationwide follow-up study

BACKGROUND

There are few epidemiologic data about the risk of acute pancreatitis in chronic inflammatory bowel diseases; we therefore wanted to estimate the risk of a first episode of acute pancreatitis in patients with Crohn's disease and ulcerative colitis in the total Danish population.

METHODS

The study included all patients discharged from Danish hospitals with a diagnosis of Crohn's disease or ulcerative colitis registered in the Danish National Registry of Patients in the period from 1977 to 1992. The first episode of acute pancreatitis was identified in the cohort. The observed number of patients with acute pancreatitis was compared with expected numbers on the basis of age, sex, and calendar-specific incidence rates in the general population.

RESULTS

Overall, 15,526 patients were discharged and followed up for 112,824 person-years. The standardized incidence ratio (SIR) for acute pancreatitis was increased both in patients with Crohn's disease (SIR = 4.3; 95% confidence interval (CI), 2.9-6.1) and in those with ulcerative colitis (SIR= 2.1; 95% CI, 1.6-2.8).

CONCLUSION

Patients with chronic inflammatory bowel disease seem to be at increased risk of acute pancreatitis. Further validation and refinement of this registration-based study are needed.

Pregnancy outcome for women with Crohn's disease: a follow-up study based on linkage between national registries

OBJECTIVE

Crohn's disease, characterized by chronic intestinal inflammation, is sometimes followed by malabsorption, which may interfere with embryogenesis and fetal growth. Therefore we examined birthweight, the frequency of preterm birth, and other reproductive outcomes in the offspring of women with Crohn's disease.

METHODS

We used a historical registry-based study, with linkage between the Danish National Registry of Patients and the Danish Medical Birth Registry. Included were 510 newborns to mothers with Crohn's disease and 3018 controls in the study period from 1982 to 1992.

RESULTS

The average birthweight of newborns to mothers with Crohn's disease was 185 g, 134 g less than expected for primiparas and multiparas. After adjusting for potential confounders the differences were 142 g (95% confidence interval [CI95%] = 76, 208) and 105 g (CI95% = 37, 173), respectively. The risk of low birthweight was increased in Crohn patients (odds ratio [OR] = 2.4; CI95% = 1.6-3.7), as was the risk of preterm birth (OR = 1.6; CI95% = 1.1-2.3).

CONCLUSION

We found a lower birthweight in newborns of patients with Crohn's disease, indicating that Crohn's disease or its treatment may influence fetal growth.

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.

Change in incidence of Crohn's disease and ulcerative colitis in Denmark. A study based on the National Registry of Patients, 1981-1992

BACKGROUND

The incidence of inflammatory bowel disease (IBD) in Denmark is considered to be among the highest in Europe. However, the diseases are relatively rare and therefore it would be useful if existing registers could replace ad hoc examination in the surveillance of IBD.

METHODS

The present study used the Danish National Registry of Patients to estimate incidence rates, 1981-1992.

RESULTS

A total of 2806 patients with Crohn's disease (CD) and 8125 with ulcerative colitis (UC) were identified. The mean incidence for CD was 4.6 (5.4 for women and 3.7 for men) per 100,000 per year, with a peak incidence in younger women. The incidence increased in most age groups with the highest increase in older women. The mean incidence for UC was 13.2 (13.4 for women and 13.0 for men) per 100,000 per year, with the highest incidence in older men. A decreasing tendency in the incidence was present in most age groups.

CONCLUSIONS

The present study found an increasing incidence for CD and a stable incidence with a tendency to decrease for UC. Comparison with ad hoc studies indicates that it is possible to use the Danish National Registry of Patients in the surveillance of IBD, especially for CD.

Assessment of the diagnoses of Crohn's disease and ulcerative colitis in a Danish hospital information system

BACKGROUND

Our aim was to estimate the completeness-that is, whether all patients were included in the system-and the validity-that is, whether the diagnostic criteria were fulfilled for the patients registered-of the diagnoses of Crohn's disease and ulcerative colitis in a Danish hospital system.

METHODS

Information in a regional hospital system, in the County of North Jutland, Denmark, was compared with hospital records and information in a pathology system.

RESULTS

The analysis of the completeness included 143 patients with Crohn's disease and 285 patients with ulcerative colitis. The completeness of the regional hospital system using the pathology system as a reference standard was 94% for both diseases. The analysis of the validity included 281 patients registered as having Crohn's disease and 506 patients registered as having ulcerative colitis. The validity of the two diagnoses was 97% and 90%, respectively.

CONCLUSIONS

The regional hospital system showed few misclassifications of the diagnoses of Crohn's disease and ulcerative colitis. Thus the nationwide hospital system (based on the regional hospital systems) may provide a unique study base for future research.