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L M Irgens

Publications and source records attributed to L M Irgens.

At least 19 recordsLinked to original sources

Vitamin A and sudden infant death syndrome in Scandinavia 1992-1995.

AIM: To assess the effect of vitamin supplementation on the risk of sudden infant death syndrome (SIDS). METHODS: The analyses are based on data from the Nordic Epidemiological SIDS Study, a case-control study in which parents of SIDS victims in the Scandinavian countries were invited to participate together with parents of four matched controls between 1 September 1992 and 31 August 1995. The odds ratios presented are computed by conditional logistic regression analysis. RESULTS: The crude odds ratio in Scandinavia for not giving vitamin substitution was 2.8 (95% CI (1.9, 4.3)). This effect was statistically significant in Norway and Sweden, which use A and D vitamin supplementation, but not in Denmark, where only vitamin D supplementation is given. The odds ratios remained significant in Sweden when an adjustment was made for confounding factors (OR 28.4, 95% CI (4.7, 171.3)). CONCLUSION: We found an association between increased risk of sudden infant death syndrome and infants not being given vitamin supplementation during their first year of life. This was highly significant in Sweden, and the effect is possibly connected with vitamin A deficiency. This effect persisted when an adjustment was made for potential confounders, includingsocioeconomic factors.

Case-Control Studies↗

Breast feeding and the sudden infant death syndrome in Scandinavia, 1992-95.

AIMS: To assess the effects of breast feeding habits on sudden infant death syndrome (SIDS). METHODS: The analyses are based on data from the Nordic Epidemiological SIDS Study, a case-control study in which parents of SIDS victims in the Scandinavian countries between 1 September 1992 and 31 August 1995 were invited to participate, each with parents of four matched controls. The odds ratios presented were computed by conditional logistic regression analysis. RESULTS: After adjustment for smoking during pregnancy, paternal employment, sleeping position, and age of the infant, the adjusted odds ratio (95% CI) was 5.1 (2.3 to 11.2) if the infant was exclusively breast fed for less than four weeks, 3.7 (1.6 to 8.4) for 4-7 weeks, 1.6 (0.7 to 3.6) for 8-11 weeks, and 2.8 (1.2 to 6.8) for 12-15 weeks, with exclusive breast feeding over 16 weeks as the reference. Mixed feeding in the first week post partum did not increase the risk. CONCLUSIONS: The study is supportive of a weak relation between breast feeding and SIDS reduction.

Breast Feeding↗

Comparative epidemiology of sudden infant death syndrome and sudden intrauterine unexplained death.

BACKGROUND: Unexplained antepartum stillbirth and sudden infant death syndrome (SIDS) are major contributors to perinatal and infant mortality in the western world. A relation between them has been suggested. As an equivalent of SIDS, only cases validated by post mortem examination are diagnosed as sudden intrauterine unexplained death (SIUD). OBJECTIVE: To test the hypothesis that SIDS and SIUD have common risk factors. METHODS: Registration comprised all stillbirths in Oslo and all infant deaths in Oslo and the neighbouring county, Akershus, Norway during 1986-1995. Seventy six cases of SIUD and 78 of SIDS were found, along with 582 random controls surviving infancy, all singletons. Odds ratios were obtained by multiple logistic regression analysis. RESULTS: Whereas SIUD was associated with high maternal age, overweight/obesity, smoking, and low education, SIDS was associated with low maternal age, smoking, male sex, multiparity, proteinuria during pregnancy, and fundal height exceeding +2 SD. Thus the effects of maternal age were opposite in SIUD and SIDS (adjusted odds ratio 1.39 (95% confidence interval 1.17 to 1.66) per year, p < 0.0005). Heavy smoking, male sex, and a multiparous mother was less likely in SIUD than in SIDS (0.22 (0.06 to 0.83), 0.22 (0.07 to 0.78), and 0.03 (<0.01 to 0.17) respectively). Overweight/obesity and low fundal height were more common in SIUD than in SIDS (7.45 (1.49 to 37.3) and 13.8 (1.56 to 122) respectively). CONCLUSIONS: The differences in risk factors do not support the hypothesis that SIDS and SIUD have similar determinants in maternal or fetal characteristics detectable by basic antenatal care.

Adult↗

Long term mortality of mothers and fathers after pre-eclampsia: population based cohort study.

OBJECTIVE: To assess whether mothers and fathers have a higher long term risk of death, particularly from cardiovascular disease and cancer, after the mother has had pre-eclampsia. DESIGN: Population based cohort study of registry data. SUBJECTS: Mothers and fathers of all 626 272 births that were the mothers' first deliveries, recorded in the Norwegian medical birth registry from 1967 to 1992. Parents were divided into two cohorts based on whether the mother had pre-eclampsia during the pregnancy. Subjects were also stratified by whether the birth was term or preterm, given that pre-eclampsia might be more severe in preterm pregnancies. MAIN OUTCOME MEASURES: Total mortality and mortality from cardiovascular causes, cancer, and stroke from 1967 to 1992, from data from the Norwegian registry of causes of death. RESULTS: Women who had pre-eclampsia had a 1.2-fold higher long term risk of death (95% confidence interval 1.02 to 1.37) than women who did not have pre-eclampsia. The risk in women with pre-eclampsia and a preterm delivery was 2.71-fold higher (1.99 to 3.68) than in women who did not have pre-eclampsia and whose pregnancies went to term. In particular, the risk of death from cardiovascular causes among women with pre-eclampsia and a preterm delivery was 8.12-fold higher (4.31 to 15.33). However, these women had a 0.36-fold (not significant) decreased risk of cancer. The long term risk of death was no higher among the fathers of the pre-eclamptic pregnancies than the fathers of pregnancies in which pre-eclampsia did not occur. CONCLUSIONS: Genetic factors that increase the risk of cardiovascular disease may also be linked to pre-eclampsia. A possible genetic contribution from fathers to the risk of pre-eclampsia was not reflected in increased risks of death from cardiovascular causes or cancer among fathers.

Cardiovascular Diseases↗

[Cerebral palsy as indicator of quality of neonatal care].

BACKGROUND: An investigation of the prevalence of cerebral palsy in relation to neonatal intensive care. MATERIAL AND METHODS: Population based study in live-born children with birthweight > or = 500 g in the Norwegian county of Vestfold over the 25-year period 1970-94 (n = 58,448). Retrospective and prospective control of cases (cases with a postneonatal origin of cerebral palsy excluded) with a minimum follow-up to four years of age. RESULTS: Cerebral palsy was diagnosed in 139 cases (2.4 per 1,000). The prevalence declined from 2.8 per 1,000 in the first five-year cohort born 1970-74, to 2.2 per 1,000 in children born in each of the three five-year cohorts born 1980-84, 1985-89, and 1990-94 (p = 0.24). The neonatal mortality rate declined significantly from 8.7 per 1,000 in the first to 2.8 per 1,000 in the last five-year cohort (p < 0.0001). The low birthweight (500-2,499 g) rate in live-born infants increased significantly in 1990-94 compared to 1985-89 (4.5% vs 3.9% respectively; p < 0.05). After a local ventilator treatment programme (operative from 1989) was established, transports of infants with severe respiratory distress syndrome to the regional hospital declined from 3 per 1,000 live-born infants to 1 per 1,000 (p < 0.0001). INTERPRETATION: A decentralised neonatal intensive care programme can be developed, with substantial decline in neonatal mortality without a corresponding increase in cerebral palsy prevalence.

Cerebral Palsy↗

Women with a history of placental abruption: when in a subsequent pregnancy should special surveillance for a recurrent placental abruption be initiated?

BACKGROUND: It is common to admit to hospital or start intensive ambulatory antenatal care of pregnant women with a previous placental abruption using the gestational age of the previous placental abruption as a starting point. In some instances, close surveillance may be commenced much earlier. There is no consensus when in a subsequent pregnancy such measures should be initiated. OBJECTIVE: The analyses aimed at the prevention of complicated (preterm, small for gestational age, or perinatal death) recurrent placental abruptions, assessing at which time in a subsequent pregnancy special surveillance should start in order to anticipate and prevent a recurrence. DESIGN: A cohort study based on the Medical Birth Registry of Norway. Calculation of gestational age specific risks of placental abruption in a second pregnancy and estimation of when to initiate surveillance in order to reduce an increased risk of recurrent placental abruption to the initial level of initial abruption in the second pregnancy. RESULTS: In women with a complicated (preterm, small for gestational age, or perinatal death) first delivery, the risks of an initial and recurrent complicated placental abruption in the second pregnancy were 7/1000 and 33/1000, respectively (relative risk 4.9). To reduce the recurrence risk in a second pregnancy to 7/1000, special surveillance six weeks prior to the gestational age of the initial abruption would be necessary. In women with an uncomplicated first delivery, the risks in the second pregnancy of an initial and recurrent complicated abruption were 3 and 19/1000, respectively (relative risk 7.1). To reduce the recurrence risk to 3/1000, surveillance at least 12 weeks prior would be necessary. CONCLUSION: The increased recurrence rate would necessitate increased awareness in terms of special surveillance in the second pregnancy. In pregnancies at risk of a recurrent placental abruption, monitoring up to three months before the gestational age of the initial abruption is necessary.

Abruptio Placentae↗

The association of Apgar score with subsequent death and cerebral palsy: A population-based study in term infants.

OBJECTIVE: To estimate the risk of adverse outcomes for newborns with a low Apgar score. STUDY DESIGN: Population-based cohort study. All 235,165 children born between 1983 and 1987 in Norway with a birth weight of at least 2500 g and no registered birth defects were followed up from birth to age 8 to 12 years by linkage of 3 national registries. Outcomes were death and cerebral palsy (CP). RESULTS: Five-minute Apgar scores of 0 to 3 were recorded for 0.1%, and scores of 4 to 6 were recorded for 0.6% of the children. Compared with children who had 5-minute Apgar scores of 7 to 10, children who had scores of 0 to 3 had a 386-fold increased risk for neonatal death (95% CI: 270-552) and an 81-fold (48-138) increased risk for CP. If Apgar scores at both 1 and 5 minutes were 0 to 3, the risks for neonatal death and CP were increased 642-fold (442-934) and 145-fold (85-248), respectively, compared with scores of 7 to 10. CONCLUSION: The strong association of low Apgar scores with death and CP in this population with a low occurrence of low scores shows that the Apgar score remains important for the early identification of infants at increased risk for serious and fatal conditions.

Apgar Score↗

Changes in the epidemiology of sudden infant death syndrome in Sweden 1973-1996.

BACKGROUND: From the early 1970s to the early 1990s, there was a significant rise in the incidence of sudden infant death syndrome (SIDS) in Scandinavia. Following the risk reducing campaign, the incidence has fallen to about the same level as in 1973. AIMS: To identify the changes that have occurred in the epidemiology of SIDS. METHODS: We compared the Swedish part of the Nordic Epidemiological SIDS Study (NESS), covering the years 1992-1995, with two earlier, descriptive studies during this period. To assess the changing effects of risk factors, we analysed data from the Medical Birth Registry of Sweden, covering the years 1973-1996. RESULTS: There was a predominance of deaths during weekends in the 1970s and 1990s. The seasonal variation was most notable in the 1980s. The proportion of young mothers decreased from 14% to 5%. Cohabitation (living with the biological father) was as frequent in the 1990s as in the 1970s. The prevalence of high parity, admissions to neonatal wards, low birth weight, prematurity, and multiple pregnancies were all increased in the 1990s compared to the 1970s. No significant change in the prevalence of previous apparent life threatening events was found. Deaths occurring in cars diminished from 10% to below 2%. In the data from the Medical Birth Registry of Sweden, there were significantly increased odds ratios after the risk reducing campaign of the risk factors smoking during early pregnancy and preterm birth. We could find no increased effects of maternal age, parity, or being small for gestational age over time. The rate of deaths at weekends remained increased; the median age at death fell from 90 to 60 days. Seasonal variation was less notable in the periods of low incidence.

Age Distribution↗

Number of births, interpregnancy interval, and subsequent pregnancy rate after a diagnosis of inflammatory rheumatic disease in Norwegian women.

OBJECTIVE: To study female reproduction, i.e., number of births, subsequent pregnancy rate, and interpregnancy interval after diagnosis of inflammatory rheumatic disease. METHODS: In a national population based cohort study, reproduction in mothers with rheumatic disease, registered with the Medical Birth Registry of Norway 1967-1995, were compared to mothers without such diagnoses. RESULTS: After diagnosis, women with rheumatic disease had a statistically significant lower mean number of births, a shorter time span of reproduction, longer interpregnancy intervals, and a reduced subsequent pregnancy rate. CONCLUSION: Altered reproduction observed in women with a rheumatic disease might reflect various mechanisms not accounted for in this study, but possibly related to the disease process, functional impairment, or medical treatment.

Adult↗

Predicting preeclampsia in the second pregnancy from low birth weight in the first pregnancy.

OBJECTIVE: To evaluate the effect of low birth weight adjusted for gestational age in first pregnancies on preeclampsia in second pregnancies and to estimate the proportion of preeclampsia in second pregnancies attributable to histories of LBW for gestational age. METHODS: We conducted a cohort study based on linked data from the Medical Birth Registry of Norway, which covered all births in 1967-1992. RESULTS: Women who delivered infants under the third percentile birth weight were three times more likely to have initial or recurrent preeclampsia in second pregnancies than those who delivered infants at or above the tenth percentile. After adjusting for maternal age, year of birth, interpregnancy interval, education, chronic hypertension, diabetes mellitus, and change of partner, the increased risk persisted. Birth weight below the tenth percentile in the first delivery accounted for 10% of the total cases of preeclampsia in the second pregnancy and 30% of recurrent cases. CONCLUSION: A history of low birth weight adjusted for gestational age is associated significantly with subsequent occurrence as well as recurrence of preeclampsia. These findings are consistent with the hypothesis of a shared etiologic factor or recurrent pathophysiologic mechanism for preeclampsia and fetal growth restriction. A history of fetal smallness for gestational age is found in a substantial proportion of all cases of preeclampsia and thus seems to be important in the etiology of preeclampsia.

Adult↗

Living conditions in early infancy in Denmark, Norway and Sweden 1992-95: results from the Nordic Epidemiological SIDS study.

The objective was to study living conditions of infants and their families in Scandinavia in the 1990s and to assess similarities and differences among the three Scandinavian countries. The emphasis is on health and normality rather than on diseases and other deviations from well-being. The subjects are the 869 controls in the Nordic Epidemiological SIDS study carried out between 1 September 1992 and 31 August 1995 in Norway, Denmark and Sweden. The controls were matched with the 244 SIDS cases for sex, age and maternity hospital. Parents of the SIDS cases and the controls filled in the same questionnaire on family, pregnancy, delivery, the neonatal and the post-perinatal period. The most striking findings were that 99% of the mothers went to regular maternity controls, 97% to well-baby clinics and 84% breastfed exclusively. On the other hand, 11% drank alcohol more than once a month during pregnancy and 29% smoked during pregnancy. Compared to official statistics, to the extent they exist, the differences were small. The material contains valuable information on normal infant care in Scandinavia in the 1990s. Living conditions of infants in Scandinavia are similar in the three countries. Differences exist, but only to a small extent.

Alcohol Drinking↗