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Jørn Olsen

Publications and source records attributed to Jørn Olsen.

At least 19 recordsLinked to original sources
PubMed2006

Stillbirth and slow metabolizers of caffeine: comparison by genotypes.

BACKGROUND: Cytochrome P4501A2 (CYP1A2) and N-acetyltransferase 2 (NAT2) are key enzymes in the metabolism of caffeine. The polymorphism of these genes facilitates the detection of fast and slow metabolizers, and if caffeine is causally related to stillbirth, we expect slow metabolizers to have a higher risk of stillbirth at any given intake of caffeine. Gluthatione S-transferase alpha1 (GSTA1) may also be active in the metabolism of caffeine as it conjugates glutathione to aromatic amines. Our study, therefore, included analyses of the association between GSTA1 and stillbirth. METHODS: A nested case non-case study among women who participated in the Danish National Birth Cohort: 142 cases of singleton stillbirths and 157 controls of singleton live births. RESULTS: Slow oxidizer status (CYP1A2), slow acetylator status (NAT2), and low activity of GSTA1 were not individually associated with the risk of stillbirth [odds ratio (OR) = 1.06, 95% confidence interval (95% CI) 0.67-1.67, OR = 0.95, 95% CI 0.60-1.51, and OR = 1.42, 95% CI 0.88-2.28, respectively]. We did, however, observe that subjects with a combination of slow CYP1A2, slow NAT2, and low GSTA1 genes had almost a 2-fold risk of stillbirth compared with subjects with other combinations of genotypes. CONCLUSIONS: We found no link between any single genotype and the risk of stillbirth. An association between a combination of genotypes and stillbirth was discovered. Caffeine may be causally related to stillbirth, but larger studies using Mendelian randomization are needed to verify this.

Acetyltransferases↗
PubMed2006

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.

Adult↗
PubMed2006

Reproductive health indicators in the European Union: The REPROSTAT project.

Our objective was to develop a set of indicators for monitoring and describing reproductive health in the European Union (EU) that reflect common concerns of the different Member States. Ideally, the indicators would possibly draw upon existing data sources. The REPROSTAT project: (i) conducted a review of existing recommendations on reproductive health indicators; (ii) suggested a set of initial indicators in consultation with representatives from relevant outside agencies and organisations; and (iii) invited 200 reproductive health experts throughout Europe to review the provisional set of indicators. The feasibility of using the REPROSTAT indicators was tested for two countries, Italy and Germany. A final set of 13 core indicators was developed, as well as another recommended indicator and four that needed further development. The pilot use of the indicators in Italy and Germany provided useful information about availability of data in different Member States. The REPROSTAT project developed a set of reproductive health indicators believed to be of relevance for planning, prevention, and caring within the EU. Further, harmonisation of data from different Member States will be needed if the benefits of these indicators are to be fully realised.

Abortion, Induced↗
PubMed2006

Bacterial vaginosis in early pregnancy is associated with low birth weight and small for gestational age, but not with spontaneous preterm birth: a population-based study on Danish women.

OBJECTIVE: To analyze the association between bacterial vaginosis (BV) in early pregnancy and preterm birth, low birth weight (LBW) and small for gestational age (SGA) in a Danish population. METHODS: A geographically defined population-based prospective study of Danish-speaking pregnant women over18 years of age enrolled before week 24 and followed until delivery. BV was diagnosed by Amsel's clinical criteria at enrolment. RESULTS: At enrolment, 13.7% had BV. BV was not associated with an increased risk of spontaneous preterm birth (crude OR 0.8 (0.5-1.5)). Nulliparity was found to affect birth weight to such a degree that this variable was used for stratification. In nulliparous women BV was associated with LBW (adj. OR 4.3 (1.5-12)) and SGA (adj. OR 1.6 (0.7-3.1)) compared to nulliparous without BV. No such associations were seen for multiparous women with BV. CONCLUSIONS: BV was not associated with spontaneous preterm birth, but was associated with both LBW and SGA in nulliparous women.

Adolescent↗
PubMed2006

Apgar scores and long-term risk of epilepsy.

BACKGROUND: Low Apgar scores are associated with high risk of neonatal death, cerebral palsy, and mental retardation, but the association between Apgar scores and long-term risk of epilepsy remains unresolved. METHODS: We carried out a population-based cohort study of 1,538,732 live newborns in Denmark between 1 January 1978 and 31 December 2002 by using national registers. The Apgar scores at 1 or 5 minutes were recorded by midwives following standardized procedures. We obtained information on epilepsy by linking the cohort with the National Hospital Register. Cohort members were followed from birth until onset of epilepsy, death, emigration, or 31 December 2002, whichever came first. RESULTS: The incidence rate of epilepsy increased consistently with decreasing Apgar scores. The incidence rate of epilepsy was 628 per 100,000 person-years for those with 5-minute Apgar scores of 1 to 3 and 86 per 100,000 person-years for those with a score of 10; the resulting incidence rate ratio was 7.1 (95% confidence interval = 5.8-8.8). The incidence rate ratios of epilepsy associated with low Apgar scores were particularly high in early childhood but remained high into adulthood. The association did not change after excluding children with cerebral palsy, congenital malformations, or a parental history of epilepsy. CONCLUSIONS: Neonates with a suboptimal Apgar score have a higher risk of epilepsy that lasts into adult life. These findings suggest that prenatal or perinatal factors play a larger role in the etiology of epilepsy than has previously been recognized.

Adult↗
PubMed2006

Paternal age and Apgar scores of newborn infants.

BACKGROUND: New evidence suggests that advanced paternal age is a reproductive hazard, but we do not know whether paternal age affects the physical conditions of newborn infants as measured by the Apgar score. METHODS: We conducted a register-based cohort study of 70,347 couples and their first singleton infants by using data from the Danish Fertility Database (1980-1996). Information on Apgar score was obtained by linking the children to the National Birth Register. RESULTS: The odds ratio for having a baby with a 1-minute Apgar score of 1-3 was 1.64 (95% confidence interval = 1.08-2.48) for fathers 45 to 49 years of age and 1.49 (0.76-2.94) for fathers 50+ years compared with fathers 20 to 29 years (P for trend = 0.011). The risk of having a 5-minute Apgar score less than 7 increased among fathers 45+ years old (P for trend = 0.178). CONCLUSIONS: Our data suggest a modest effect of advanced paternal age on the Apgar score.

Adult↗
PubMed2006

Occupational exposure to pesticides and pregnancy outcomes in gardeners and farmers: a study within the Danish National Birth Cohort.

OBJECTIVE: We conducted a follow-up study to examine whether exposure to pesticides during pregnancy had an adverse effect on pregnancy outcomes among Danish gardeners and farmers. METHODS: Using data from the National Birth Cohort in Denmark, we identified 226 pregnancies of gardeners and 214 pregnancies of farmers during 1997 through 2003. Work activities and exposure to pesticides were reported in an interview (around 16 weeks of gestation). Totally, 62,164 other workers in the cohort served as a reference group. Pregnancy outcomes were obtained by linkage to the national registers. Cox regression was applied to analyze late fetal loss and congenital malformations, and logistic regression was used to analyze preterm birth and small for gestational age. RESULTS: There were no significant differences in the studied pregnancy outcomes between gardeners or farmers and all other workers, except for an increased risk of very preterm birth for gardeners and a favorable birth weight for farmers. With the exception of biologic approach used in gardening, neither work activities nor exposure to pesticides showed a significant increased risk of adverse birth outcomes among gardeners or farmers. CONCLUSIONS: Our data suggest little effect of occupational exposures to pesticides on pregnancy outcomes among gardeners or farmers in Denmark. The results may not apply to other countries.

Adult↗
PubMed2006

Quality of life and depression in a population of occupational hand eczema patients.

Occupational hand eczema (OHE) is the most frequently recognized occupational disease in Denmark, and despite governmental attempts to reduce exposure to harmful occupational allergens, the number of new cases has remained almost unchanged since the mid-1990s. Some studies have indicated that OHE has considerable impact on quality of life (QoL) and may lead to depression. The aims of the study were to determine risk factors for low QoL, the frequency and severity of depression among OHE patients and changes in QoL and depression after 12 months of follow up. The study population, 758 patients, comprised all new recognized cases from the Danish National Board of Industrial Injuries Registry between October 2001 and November 2002. All patients received a questionnaire to determine impairment of QoL and depressive symptoms. A similar follow-up questionnaire was posted after 1 year. The response rate was 82% at baseline and 91% at follow up. The mean Dermatology Life Quality Index total score was 5.5 for all patients and 7.8 for severe OHE cases. Severe OHE cases and lower socioeconomic status were independently associated with low QoL. The prevalence of moderate-to-severe depression was 9%. Only minor changes in QoL and depressive symptoms were found after 12 months of follow up.

Adolescent↗
PubMed2006

Pregnancy outcomes among female hairdressers who participated in the Danish National Birth Cohort.

OBJECTIVES: The Danish National Birth Cohort (DNBC) was used to examine pregnancy outcomes among female hairdressers and neurodevelopment in their offspring. METHODS: A population-based cohort study was conducted of 550 hairdressers and 3216 shop assistants (reference group) by using data from the Danish National Birth Cohort between 1997 and 2003. Information on job characteristics was reported by the women in the first interview (around 17 weeks of gestation). Pregnancy outcomes were obtained by linkage to the national registers. Developmental milestones were reported by the mother at the fourth interview, when the child was approximately 19 months old. Cox regression was applied to analyze fetal loss and congenital malformation. Logistic regression was used to analyze other pregnancy outcomes and developmental milestones. RESULTS: We found no significant differences in fetal loss, multiple births, gender ratio, preterm birth, small-for-gestational age, congenital malformations, or achievement of developmental milestones among the children of hairdressers and shop assistants. CONCLUSIONS: The results do not indicate that children of hairdressers in Denmark currently have a high risk of fetal impairment or delayed psychomotor development.

Abortion, Spontaneous↗
PubMed2005

The Danish National Hospital Register is a valuable study base for epidemiologic research in febrile seizures.

BACKGROUND AND OBJECTIVES: We examined the quality and completeness of the discharge diagnosis of febrile seizures in the Danish National Hospital Register (DNHR). METHODS: We invited all children born at the Department of Obstetrics, Aarhus University Hospital, Denmark, between January 1990 and April 1992, to participate in the study. We collected information on febrile seizures in March 2001 by mailing a questionnaire to the mothers. Reported febrile seizures were verified by telephone interviews or review of medical records. We linked the cohort to the DNHR by means of a unique civil registry number assigned to all Danish citizens at birth. Overall, 6,624 (73%) children participated in the study. RESULTS: We found that 323 (4.9%) children in the cohort had had febrile seizures, and 231 of those were registered in the DNHR (completeness: 71.5%, 95% CI: 66.3-76.4). Furthermore, we confirmed the diagnosis in 231 of 249 children registered with febrile seizures in the DNHR (predictive value of a positive registration: 92.8%, 95% CI: 88.8-95.7). CONCLUSION: The Danish National Hospital Register is a valuable tool for epidemiologic research in febrile seizures.

Child↗
PubMed2005

Coffee and fetal death: a cohort study with prospective data.

The authors conducted a cohort study within the Danish National Birth Cohort to determine whether coffee consumption during pregnancy is associated with late fetal death (spontaneous abortion and stillbirth). A total of 88,482 pregnant women recruited from March 1996 to November 2002 participated in a comprehensive interview on coffee consumption and potentially confounding factors in pregnancy. Information on pregnancy outcome was obtained from the National Hospital Discharge Register and medical records. The authors detected 1,102 fetal deaths. High levels of coffee consumption were associated with an increased risk of fetal death. Relative to nonconsumers of coffee, the adjusted hazard ratios for fetal death associated with coffee consumption of 1/2-3, 4-7, and > or =8 cups of coffee per day were 1.03 (95% confidence interval (CI): 0.89, 1.19), 1.33 (95% CI: 1.08, 1.63), and 1.59 (95% CI: 1.19, 2.13), respectively. Reverse causation due to unrecognized fetal demise may explain the association between coffee intake and risk of fetal death prior to 20 completed weeks' gestation but not the association with fetal loss following 20 completed weeks' gestation. Consumption of coffee during pregnancy was associated with a higher risk of fetal death, especially losses occurring after 20 completed weeks of gestation.

Abortion, Spontaneous↗
PubMed2005

[Should the sensible drinking limits for adults be changed?].

The sensible drinking limits may be too high depending on sex, age, genetic variation and other factors. Recent research on the alcohol-related risk of breast cancer and the impact of drinking patterns on health calls for an update of the literature. We focus on studies of the effect of alcohol on morbidity and mortality and conclude that the maximum of 21 drinks per week for men and 14 for women may be maintained. We emphasize that episodic intake of alcohol increases the risk of death and that the beneficial effect of alcohol is reached at an intake of one drink per day. We also specify groups for whom the drinking limits are not valid.

Adult↗
PubMed2005

Paternal age and congenital malformations.

BACKGROUND: Spontaneous mutations in germ cells increase with male age, but an association between paternal age and congenital malformations is not well established. We conducted a population-based cohort study to estimate this association. METHODS: A study population of couples and their firstborn children were identified in the Danish Fertility Database between 1980 and 1996 (n = 71937). Diagnoses of congenital malformations in children were obtained by linkage to the nationwide hospital register (1980-1999). RESULTS: Overall, there were no differences in the prevalence of malformations as a function of paternal age. However, the prevalence of malformations of extremities and syndromes of multiple systems, as well as Down's syndrome, increased with increasing paternal age. For example, in comparison with fathers age 20-29 years, adjusted hazard ratio of syndromes of multiple systems was 1.15 [95% confidence interval (CI) 0.81-1.65] for age 35-39 years, 1.33 (95% CI 0.79-2.25) for age 40-44 years, 1.73 (95% CI 0.82-3.65) for age 45-49 years, and 3.20 (95% CI 1.37-7.48) for age > or = 50 years (test for trend P = 0.01). CONCLUSIONS: Our data suggest that advanced paternal age may be associated with an excess occurrence of some specific malformations. The association could be caused by mutations of the gametes in men induced by biological or environmental factors.

Abnormalities, Multiple↗
PubMed2005

Male reproductive disorders in humans and prenatal indicators of estrogen exposure. A review of published epidemiological studies.

Male reproductive disorders in humans and prenatal indicators of estrogen exposure. A review of published epidemiological studies. Reports of an increase in male reproductive disorders in several countries led to the hypothesis that estrogens during fetal life may cause reduced sperm counts, cryptorchidism, hypospadias and testicular cancer. So far the hypothesis is based on animal studies and reports from the wild life. We systematically searched the epidemiological literature for evidence linking indicators of prenatal serum levels of maternal estrogens with sperm density, hypospadias, cryptorchidism and testicular cancer in humans. Indicators of fetal estrogen exposure included direct measurements, recorded intake of hormones (diethylstilbestrol (DES), oral contraceptives (OCs) and estrogens), pregnancy conditions with known deviant estrogen level as for instance twin pregnancies and some environmental exposures. Among 425 papers we reviewed 81 publications with appropriate information. With the possible exception of testicular cancer there is no strong epidemiological evidence to indicate that prenatal exposure to estrogen are linked to disturbed development of the male reproductive organs.

Cryptorchidism↗
PubMed2005

Cancer risk in persons with oral cleft--a population-based study of 8,093 cases.

The authors conducted a nationwide study of the occurrence of cancer among 8,093 Danish oral cleft cases born in 1936 through 1998 and followed in the Danish Cancer Registry from 1968 through 1998, a total of 175,863 person-years, to assess a possible association between cancer and oral clefts. Observed and expected numbers of cancers among oral cleft cases were summarized as the overall and as 52 site-specific standardized incidence ratios. The expected overall number of all cancers was 131, but 140 incident cancers were found, corresponding to a standardized incidence ratio of 1.07 (95% confidence interval (CI): 0.90, 1.26). Analyses of the 52 sites for all oral cleft cases and analyses stratified for three cleft subgroups and the two sexes revealed only a few significant associations: an increased occurrence of breast cancer among females born with cleft lip and/or cleft palate (standardized incidence ratio (SIR) = 1.52, 95% CI: 1.05, 2.14), primary brain cancer among females born with cleft palate (SIR = 3.11, 95% CI: 1.14, 6.78), and primary lung cancer among males born with both cleft lip and cleft palate (SIR = 2.49, 95% CI: 1.00, 5.14). The results do not provide evidence for an increased overall cancer risk for individuals born with oral clefts.

Adolescent↗