Clustering of acute respiratory infection hospitalizations in childcare facilities

AIM

To estimate how risk of acute respiratory infection (ARI) hospitalization in children attending childcare facilities with a recently (within 1 month) hospitalized child is affected by gender, age and other characteristics.

METHODS

Population-based prospective cohort study of 436 434 Danish 0-5-year-old children attending childcare during 1989-2004. Information was collected from Danish registers. Main outcome measure was incidence rate ratios (IRRs) of in-patient hospitalization for ARI.

RESULTS

During 1 777 999 person-years of follow-up 42 681 hospitalizations for ARI occurred, of which 362 (1%) occurred within 1 month after another child was hospitalized for ARI in the facility. Children attending a facility with a recent ARI hospitalization had an increased risk of 42% (95% CI 27%;60%) compared with other children. The increased risk was higher in 0-2-year-old children than in 3-5-year-old children (55% vs 17%, p = 0.02) and if the latest hospitalized child was 0-2 years rather than 3-5 years (52% vs 19%, p = 0.04). The increased risk was similar in boys and girls, but was higher if the latest hospitalized child was a boy rather than a girl (52% vs 13%, p = 0.02).

CONCLUSION

Although occurring infrequently, clustering of ARI hospitalizations involve 0-2-year-olds and boys as first hospitalized child relatively more often than would be expected.

[22q11 deletion syndrome]

22q11 deletion syndrome (formerly named CATCH22, DiGeorge, Velo-Cardio-Facial, Caylor, Kinouchi and Shprintzen syndrome) occurs in approximately 1/2000 to 4000 children. The genetic lesion is remarkably uniform, occurring mainly as 3 or 1.5 MB deletions in the 22q11.2 region. However, the clinical manifestations are variable and manifestation in several organ systems often occur. In this review we describe the various manifestations of the syndrome. Finally, we suggest strategies for diagnosing, evaluating and organizing the treatment for Danish patients with this syndrome.

Association between social position and congenital anomalies: A population-based study among 19,874 Danish women

Aims: To examine the association between maternal and paternal educational level and household income and the risk of giving birth to a baby with a congenital anomaly in a population of Danish women. Methods: We performed a population-based cohort study, based on record linkage of data from Danish administrative registries. For each pregnant woman in the cohort, we described financial and educational resources and congenital anomalies in her offspring. We used logistic regression to model the association between social position and congenital anomalies. Results: The analyses included all 19,874 primiparous singleton deliveries in North Jutland county, Denmark, from 1991 to 1998. There were 1025 (5.2%) babies with congenital anomalies. The odds ratios (ORs) for giving birth to a baby with a congenital anomaly showed a dose— response decline, as the mothers' educational level increased. Women with less than 10 years of schooling had an almost three-fold increased risk of giving birth to an infant with a congenital anomaly, as compared with women with more than 4 years of higher education (OR=2.9, 95% confidence interval = 1.8—4.6). Paternal educational level and household income were, to a lesser degree, associated with congenital anomalies in the offspring. Conclusions: Maternal educational level, and to a lesser degree paternal educational level and household income, were associated with the risk of giving birth to a baby with a congenital anomaly. However, the analysis did not take into account maternal health status, and the results might be due to differential misclassification or residual confounding.

Associations between socio-economic factors and the use of prescription medication during pregnancy: a population-based study among 19,874 Danish women

OBJECTIVE

To examine the association between socio-economic factors and use of prescription medication during pregnancy in a population of Danish women.

METHODS

This was a population-based cohort study. Using record linkage from public administrative registries, we described the use of prescription medication during pregnancy and the financial and educational resources for each pregnant woman in the cohort.

RESULTS

The analyses included all 19,874 primiparous women delivering singletons in North Jutland county, Denmark, in 1991-1998. We identified 24,243 prescriptions filled by the women during their pregnancies. The highest overall prescription medication use was among women with basic schooling (OR 1.3; 95% CI 1.2-1.4), and lowest among women with the highest education (OR: 0.8; 95% CI 0.7-0.9) compared with women who had vocational education. Stratified analysis of therapeutic subgroups revealed that socio-economic factors were associated with the use of anti-infective and anti-asthmatic medications during pregnancy.

CONCLUSION

Maternal educational level, and to a lesser degree household income, paternal educational level and cohabitation status, was associated with the use of prescription medication during pregnancy. However, the analyses did not take into account important clinical variables such as maternal illness, and the results could be affected by differential misclassification of exposure information, by confounding or chance.

Temporal trend in paediatric infections in Denmark

AIM

To study temporal trends in the incidence of hospitalisations due to infection in children in Denmark.

METHODS

A national register based cohort of 1 892 711 Danish children aged 0-5 years were studied from 1980 to 2001. Child and family characteristics were identified in the Danish Civil Registration System; hospitalisations were identified in the Danish National Patient Registry. Annual incidence rates were estimated using log-linear Poisson regression.

RESULTS

During the studied period, the incidence of hospitalisations from infection increased by 62% in 0-5 year old children. The increase was mainly due to a sevenfold increase in the incidence of infections leading to short term hospitalisation in children aged 0-1 years. Since the increase in incidence was contrasted with a decrease in duration of hospitalisation, no further strain was put on the health services in Denmark.

CONCLUSION

During the last two decades, the incidence of short term hospitalisations due to infections increased markedly among the youngest children. However, the strain on the health services remained constant. The observed increase in the incidence of short term hospitalisations among the youngest children may reflect changes in hospitalisation practices and utilisation, rather than an increase in incidence of infections.

Socioeconomic factors and risk of hospitalization with infectious diseases in 0- to 2-year-old Danish children

Although the association between low socioeconomic status and illness in childhood is well known, the impact of socioeconomic factors on risk and frequency of hospitalizations for infectious diseases, the most frequent disease category, during the first 2 years of life has scarcely been studied. Through linkage of records drawn from public administrative and health registries, we conducted a population-based cohort study of 5024 Danish children born in 1997 to examine the frequency of hospitalization for infectious diseases in very young children. The main exposure variables, adjusted for potential confounding factors, were mother's education level, household income, and cohabitation status. The outcome was number of hospital admissions (0, 1-2, or 3+) for infectious diseases. A total of 737 children (14.7%) were admitted to hospital 1-2 times, and 83 (1.6%) were admitted 3-10 times. The risk of hospitalization was increased in children of mothers with a low level of education compared with vocational education (1-2 admissions: adjusted odds ratio (OR) 1.3 (95% confidence interval [CI]: 1.1-1.6). Children from low-income families had an increased risk of 3 or more admissions (low cf middle income: adjusted OR 2.0 [95% CI: 0.6-6.0]). Children of single mothers had an increased risk of hospitalization (1-2 admissions: adjusted OR 1.7 [95% CI: 1.1-2.6]. We found the highest risk of hospitalization for infectious diseases in children of mothers with only basic schooling, and particularly among those coming from single parent homes with a low income.

Psychosocial distress during pregnancy and the risk of infantile colic: a follow-up study

AIM

To examine the association between psychosocial exposures during pregnancy and the risk of infantile colic.

METHODS

The study included 378 infants and was conducted as a substudy of the Danish National Birth Cohort from 1997 to 1999, with prenatal data collected twice during pregnancy. A diary with a record for postpartum weeks 4-8 was used to quantify the amount of the infants' crying and fussing.

RESULTS

The cumulative incidence proportion of infantile colic was 8.2%. A threefold increased risk of infantile colic (OR = 3.7; 95% CI: 1.1-13.2) was found for mothers who reported distress during pregnancy. Close to a twofold increased risk of IC was found for the women who scored higher than 8 on the psychological distress scale (adjusted OR = 1.9; 95% CI: 0.5-7.2).

CONCLUSION

The results indicate that general distress during pregnancy influences the risk of infantile colic. Whether or not this relationship is causal requires further investigations.

Socioeconomic factors and prescription of antibiotics in 0- to 2-year-old Danish children

OBJECTIVES

The aim was to examine the impact of socioeconomic factors on the use of systemic antibiotics during the first 2 years of life.

METHODS

This was a population-based cohort study of 5024 Danish children born in 1997. The study was conducted by linking records drawn from public administrative registries. The main predictor variables were mother's education level, household income and cohabitation status. The outcome was the number of antibiotic courses (0, 1-5, > or =6) during the first 2 years of life.

RESULTS

A total of 3273 children (65.1%) received 1-5 antibiotic courses, and 337 (6.7%) received > or =6 courses of antibiotics during the first 2 years of life. The risk of receiving > or =6 courses of antibiotics was increased in children of mothers with a low educational level (< or =10 years) compared with vocational education [OR 1.3 (95% CI 1.0-1.7)]. Children of mothers with a higher education >4 years had a reduced risk of receiving > or =6 courses [OR 0.3 (95% CI 0.1-0.7)]. Children from high-income families had a reduced risk (not statistically significant) of receiving antibiotics, compared with children from middle-income families [1-5 and > or =6 courses: adjusted OR 0.6 (95% CI 0.3-1.2)]. Children of single mothers had an increased risk of receiving antibiotics, particularly if the child did not attend day care.

CONCLUSIONS

Socioeconomic factors have some impact on antibiotic prescription in young children. Children of mothers with only basic schooling were at highest risk of receiving multiple prescriptions, whereas children of mothers with a high education, and/or high household income, had the lowest risk.

[Repeat antibiotic prescriptions following treatment with sulfonamide or pivmecillinam. A survey of prescriptions among women aged 15-50 years in the county of Nordjylland]

INTRODUCTION

A sulphonamide is the antibiotic of first choice for the treatment of uncomplicated urinary tract infections in Denmark. However, this recommendation has been challenged.

MATERIAL AND METHODS

The study comprised 9,224 women, aged 15 to 50 years, who were residents in the County of North Jutland, Denmark. During 1997-1998 they had handed in a prescription from a general practitioner for either sulphonamide or pivmecillinam, but no other prescriptions for antibiotics during the preceding six months. Any antibiotic prescription handed in within the ensuing 31-day period was recorded, with the exception of macrolides. The proportion of women with a repeat prescription was a proxy for therapeutic failure.

RESULTS

Eight thousand two hundred and sixty-nine women (89.6%) had handed in a prescription for a sulphonamide and 955 (10.4%) a prescription for pivmecillinam. A total of 1,490 women (16.2%) handed in a repeat prescription, i.e. 16.0% (95% confidence limits [CI] 15.2-16.8%) of women treated with sulphonamide and 17.8% (95% CI 15.4-20.4%) of women treated with pivmecillinam. The relative risk of a repeat prescription was 1.11 (95% CI 0.95-1.31) for women with a primary prescription for pivmecillinam, as compared to women with a sulphonamide prescription. Women who had handed in a sulphonamide prescription for less than three defined daily doses had an increased risk of a repeat prescription.

DISCUSSION

The proportion of women with a repeat prescription did not differ much between women treated with sulphonamide and those treated with pivmecillinam. Controlled clinical trials should be performed before revision of current Danish recommendations are considered.

Do pregnant women report use of dispensed medications?

Surveillance of drug safety in pregnancy often draws on administrative prescription registries. Noncompliance in the use of prescribed medication may be frequent among pregnant women owing to their fear of fetotoxic side effects. To estimate compliance in the use of prescription drugs dispensed during pregnancy, we compared prescription data from the North Jutland Prescription Database with information on drug use provided by pregnant women to the Danish National Birth Cohort (DNBC), which is a health interview survey. We used the North Jutland Prescription Database to identify all prescription drugs dispensed during pregnancy for the 2,041 women who were enrolled in the DNBC in the County of North Jutland, Denmark. Compliance was defined as the probability of reporting drug use in DNBC after purchasing a dispensed prescription drug. The overall compliance to drugs purchased within 120 days before the interview was 43% (95% confidence interval = 40-46). Drugs used for treating chronic diseases, for example, beta-blockers, insulin, thyroid hormones, and diuretic and antiepileptic drugs, were always reported to be used, but compliance was low for drugs used for local or short-term treatment such as antihistamines, antibiotics, antacids, nonsteroid anti-inflammatory drugs, and gynecologic drugs. Thus, for the latter drug groups the prescription database may provide an incomplete identification of exposure. Neither data source is unbiased regarding actual drug intake. Nevertheless, our results indicate that for some drug groups risk assessment studies based on prescription data may produce false negative results as a result of noncompliance.

A population-based prescription study of asthma drugs during pregnancy: changing the intensity of asthma therapy and perinatal outcomes

BACKGROUND

Among the goals of gestational asthma, therapy is optimisation of pulmonary function. According to the US Food and Drug Administration, no asthma drugs can be considered 'safe' during pregnancy. Fear of adverse fetal effects may thus lead to restrictive use of asthma drugs during pregnancy, and no population-based studies concerning gestational asthma therapy exist.

OBJECTIVES

To examine whether asthma drugs or changing intensity of asthma therapy during pregnancy was associated with deviations from expected values of gestational age, birth weight, length at birth, or malformations.

METHODS

The Birth Registry was used to identify all 15,756 primiparous women who gave birth in the County of North Jutland between 1991 and 1996. According to the North Jutland Prescription Database, 303 of these women received prescriptions for asthma drugs during pregnancy. Women who did not purchase any prescription drugs during pregnancy constituted the reference group.

CONCLUSION

Women who received prescriptions for asthma drugs during pregnancy gave birth to infants with birth weight and length at birth within the expected limits. Reducing intensity of asthma treatment during pregnancy was associated with lower birth weight and length at birth. This may indicate that pregnant women chose to discontinue therapy although their disease severity justifies continuation of treatment. However, analyses did not take into account important clinical variables, and results could also be due to confounding factors or chance.

Influence of day care attendance on the use of systemic antibiotics in 0- to 2-year-old children

OBJECTIVE

To examine the association between time spent in different public day care settings and prescription of systemic antibiotics. Design. Population-based cohort study of 5035 Danish children born in 1997 followed from birth to June 30, 1999.

METHODS

The study was performed by the linkage of records drawn from administrative registries. Exposure was the total time spent in a day care home or day care center. Outcome was the first prescription of a systemic antibiotic. Possible perinatal and sociodemographic confounding factors were considered by statistical analysis.

RESULTS

During the first year of life, 39.8% of the girls and 51.1% of the boys received at least 1 antibiotic prescription drug. Enrollment in a day care setting doubled a child's risk of receiving a prescription drug (adjusted relative risk in day care home 1.9, 95% confidence interval: 1.7-2.0; adjusted relative risk in day care center 2.0, 95% confidence interval: 1.7-2.3). Only age confounded the analyses. Age >1 year at the starting time in day care reduced the risk of receiving antibiotic prescriptions during the first 3 months after enrollment.

CONCLUSIONS

Enrollment in public day care facilities raised the risk of receiving an antibiotic prescription drug to the same extent in day care homes as well as in day care centers, so we cannot recommend one facility over the other based on the present study. Children <1 year old at enrollment were most at risk, suggesting that extension of parental leave may reduce the use of antibiotics.

Effect of diuretics on fetal growth: A drug effect or confounding by indication? Pooled Danish and Scottish cohort data

AIMS

The diabetogenic effect of diuretics, as well as the indication for prescribing them, may impact on fetal growth. We analysed whether the purchase of prescription drugs for diuretics during pregnancy was associated with measures of fetal growth.

METHODS

During 1991-98 all women who purchased prescription drugs for diuretics during pregnancy were identified in the Northern Jutland Prescription Database (NJDP), Denmark, and in the Medicines Monitoring Unit's Database (MEMO), Scotland. Information on birth weight and gestational age was obtained from the Danish Birth Registry, the Danish Hospital Discharge Registry and the Scottish Tayside Neonatal Database. Information on diabetes, hypertension and prepregnancy weight were obtained by hospital record review in a sample of women in the Danish cohort. Women who did not purchase prescription diuretics during pregnancy were used as a reference group in both cohorts.

RESULTS

Danish women who purchased prescription loop diuretics during pregnancy gave birth to infants with higher birth weights than women who did not use diuretics; mean difference 104.7 g (95% CI; 2.6, 206.9). However, the high prevalence of diabetes (10.3%) among Danish women who purchased prescription loop diuretics during pregnancy might explain this result. Both the Danish and the Scottish women who purchased prescription diuretics during their pregnancy were at increased risk of preterm delivery (< 37 completed weeks); ORs: 1.8 (CI; 1.2, 2.7)NJDP, 1.9 (CI; 0.9, 4.3)MEMO. The proportion of hypertension among women who purchased prescription thiazides was 15.8%, and the risk of having an infant with a birth weight (BW) < 2500 g was increased; ORs: 2.6 (CI; 1.4, 5.0)NJDP, 2.4 (CI; 0.8, 7.8)MEMO.

CONCLUSIONS

Prescribing diuretics during pregnancy was associated with differences in birth weight and incidence of preterm delivery. Confounding by indication may explain the findings.

Individual use of antibiotics and prevalence of beta-lactamase production among bacterial pathogens from middle ear fluid

Prescription data and clinical laboratory data were analysed to assess the influence of previous antibiotic therapy on the prevalence of beta-lactamase in isolates of Haemophilus influenzae and Moraxella catarrhalis from primary specimens of middle ear fluid from 2129 children aged 0-5 years. The prevalence of beta-lactamase-positive H. influenzae was 6.6% [95% confidence interval (CI): 3.5-9.8%] in children who received antibiotics 5-90 days before isolation of the organism compared with 7.0% (95% CI: 3.9-10.2%) in those who did not. The prevalence of beta-lactamase-positive M. catarrhalis was 90.9% (95% CI: 84.0-97.8%) in children who received antibiotics compared with 86.7% (95% CI: 79.0-94.4%) in those who did not.

[Drug prescriptions for Danish children]

We used a prescription database to identify all reimbursed prescriptions for children aged 0-15 years living in North Jutland County (population 95,134), Denmark, during 1997. We identified 154,189 prescriptions for 48,091 child users. The mean prescription rate was 1621/1000 children/year. Overall, half of the child population purchased > or = 1 prescription. In children younger than three years, 75.3% purchased prescriptions, and 17.5% received > or = 5 prescriptions. Systemic antibiotics, anti-asthmatics, ophthalmologicals, and dermatological corticosteroids accounted for 82% of the prescriptions. One-third of the 0-2 year old children purchased prescriptions for anti-asthmatics, mainly systemic beta 2-agonists, and almost half purchased antibiotics, mainly broad-spectrum penicillins. In the 7-15 year olds, 39.1% redeemed at least one prescription. The study stresses the need for epidemiological studies on the reasons for drug use and evaluation of pharmacological effects in children.

Multiple prescriptions of antibiotics for children aged 0 to 5 years in relation to type of antibiotic

The risk of receiving more than one prescription within an antibiotic course was examined for all children aged 0 to 5 years in a Danish county during 1997. We identified 29,307 prescriptions of systemic antibiotics for 16,245 children in a prescription database. Ten per cent of the prescriptions were followed by a new prescription within 10 days. In children who received two prescriptions (n = 3993), 19% redeemed the prescriptions within the same course. When the child was prescribed penicillin V, compared with broad-spectrum penicillin, the odds ratio of receiving a repeat prescription within 1-2 days was 2.9 (95% CI 2.5-3.4) and within 3-10 days 1.3 (95% CI 1.2-1.5).

A one-year population-based study of drug prescriptions for Danish children

We examined the pattern of prescribed drug use in Danish children and used a pharmacoepidemiological prescription database to identify all reimbursed prescriptions for children aged 0-15 y living in North Jutland County (population 95 189), Denmark, during 1997. We identified 154 189 prescriptions for 48 091 drug users. The 20 most frequently prescribed chemical substance subgroups comprised 71.3% of all prescriptions. The mean annual prescription rate was 1621/1000 children/y. Overall, 50.6% of the population received one or more prescription. In children younger than 3 y, 75.3% received prescriptions and 17.5% obtained five or more prescriptions. Systemic antibiotics, anti-asthmatics, ophthalmologicals and dermatological corticosteroids accounted for 82% of prescriptions. One-third of the young children received anti-asthmatics, mainly oral beta-2 agonists, and almost half received antibiotics, mainly broad-spectrum penicillins. In the 7-15-y-olds, 39.1% received prescriptions. Hormones, antihistamines, anti-epileptics, anti-acne preparations and anti-diabetics comprised an increasing proportion of prescriptions. About 20% received antibiotics and 6% anti-asthmatics. In conclusion, the level of exposure to prescribed drugs was considerable at all ages and was highest in early childhood. Our study supports the need for epidemiological studies on the reasons for drug use and evaluation of their pharmacological effects in children.

A population-based study of antibiotic prescriptions for Danish children

BACKGROUND

The aim of the study was to examine the use of systemic and topical antibiotics in relation to age and sex in Danish children.

METHODS

We used the Pharmacoepidemiological Prescription Database to identify the individual prescriptions of antibiotics provided for all 0-to 15-year-old children in North Jutland County, Denmark, during 1997. The population was approximately 95000 children.

RESULTS

We identified 44640 prescriptions for systemic antibiotics. The annual prescription rate was highest in the 1- to 2-year-olds, with 945 prescriptions/1000 children/year. One-half of these children received at least 1 prescription, and 12% received 3 or more prescriptions. Among the 11- to 15-year-old children 17% received one or more prescriptions. Overall 88% of the prescriptions were penicillins and 10% were macrolides. In children younger than 3 years 57% of prescriptions were for broad spectrum penicillins, but in children older than 6 years penicillin V was the most frequently used antibiotic. We identified 12 661 prescriptions for topical antibiotics used in eye infections. The prescription rate peaked in the 1- to 2-year-old children, one-third of whom received at least 1 prescription.

CONCLUSIONS

Almost two-thirds of the 0- to 2-year-old children in the population were treated with either systemic or topical antibiotics during 1 year. Physicians prescribe mostly penicillins, but the proportion of broad spectrum penicillins for young children was so high, however, that enforcement of national guidelines should be reconsidered.