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Biomedical subjects

S F Olsen

Publications and source records attributed to S F Olsen.

At least 37 records · Page 2Linked to original sources
PubMed1999

Smoking habits among pregnant Danish women: reliability of information recorded after delivery.

STUDY OBJECTIVE: To compare recall of smoking habits during pregnancy 0.5-3 years after delivery across groups defined by recall time (5 six month periods) and pregnancy outcome (pre-eclampsia, pregnancy induced hypertension, intrauterine growth retardation, preterm or post-term delivery compared with controls). DESIGN: Case-control nested in cohort study. SETTING AND PARTICIPANTS: A subsample of 503 women from a cohort of 6347 women established between 1989 and 1991 in Aarhus University Hospital. MAIN RESULTS: Measures of agreement between concurrent and retrospective data on smoking status varied between 0.93 and 1.0 (sensitivity), 0.90 and 0.98 (specificity), and 0.79 and 0.98 (kappa). Spearman's correlation coefficients for number of cigarettes smoked/day varied between 0.87 and 0.97; mean differences were all close to zero. Accuracy of recall tended to diminish with increasing alcohol intake, particularly among women smoking > or = 10 cigarettes/day. CONCLUSIONS: Information on smoking habits could be accurately obtained retrospectively independent of recall time and the pregnancy outcomes studied here. Accuracy diminished with increasing alcohol intake, particularly among heavy smokers.

Case-Control Studies↗
PubMed1998

Overt and relational aggression in Russian nursery-school-age children: parenting style and marital linkages.

Maternal and paternal parenting styles and marital interactions linked to childhood aggressive behavior as described in Western psychological literature were measured in an ethnic Russian sample of 207 families of nursery-school-age children. Results corroborated and extended findings from Western samples. Maternal and paternal coercion, lack of responsiveness, and psychological control (for mothers only) were significantly correlated with children's overt aggression with peers. Less responsiveness (for mothers and fathers) and maternal coercion positively correlated with relational aggression. Some of these associations differed for boys versus girls. Marital conflict was also linked to more overt and relational aggression for boys. When entered into the same statistical model, more marital conflict (for boys only), more maternal coercion, and less paternal responsiveness were found to be the most important contributors to overt and relational aggression in younger Russian children.

Adult↗
PubMed1997

Marine n-3 fatty acid and calcium intake in relation to pregnancy induced hypertension, intrauterine growth retardation, and preterm delivery. A case-control study.

OBJECTIVE: To evaluate whether low intakes in pregnancy of marine n-3 fatty acids or calcium increase the risk of preeclampsia, pregnancy induced hypertension, intrauterine growth retardation, or preterm delivery and whether high intakes of the above nutrients increase the risk of postterm delivery. DESIGN: A case-control nested in cohort study. SUBJECTS AND METHODS: Between 1989 and 1991 a cohort of 9,434 pregnant women was established. Forty-three preeclamptics, 179 women with pregnancy induced hypertension, 182 with intrauterine growth retardation, 153 delivering preterm, and 189 delivering postterm together with 256 controls were sampled for this study. Dietary information was obtained retrospectively between six months and 3 1/2 years after delivery using a semiquantitative food frequency questionnaire, whilst information on potential confounders was obtained from the cohort data base and analyzed by multiple logistic regression. Questions regarding marine n-3 fatty acids and calcium intake provided the basis for categorization into three and five intake groups respectively. RESULTS: For all five pregnancy outcomes and both nutritional factors, none of the confounder-adjusted odds ratios comparing higher intake levels with the lowest intake level were significant. Neither were chi 2-tests for trend calculated for each pregnancy outcome statistically significant (p > 0.20). Odds ratios for highest versus lowest intake levels were for n-3 fatty acids 0.79 ((0.27 to 2.34 (95% CI)) for pregnancy induced hypertension, 1.00 (0.34 to 2.95) for intrauterine growth retardation, and 0.99 (0.35 to 2.74) for preterm delivery; for calcium they were 0.92 (0.33 to 2.60) for pregnancy induced hypertension, 0.77 (0.25 to 2.42) for intrauterine growth retardation, and 1.05 (0.36 to 3.10) for preterm delivery. CONCLUSIONS: No associations could be detected in these data between calcium or fish intake and adverse pregnancy outcome.

Adult↗
PubMed1996

Cluster analysis and disease mapping--why, when, and how? A step by step guide.

Growing public awareness of environmental hazards has led to an increased demand for public health authorities to investigate geographical clustering of diseases. Although such cluster analysis is nearly always ineffective in identifying causes of disease, it often has to be used to address public concern about environmental hazards. Interpreting the resulting data is not straightforward, however, and this paper presents a guide for the non-specialist. The pitfalls include the fact that cluster analyses are usually done post hoc, and not as a result of a prior hypothesis. This is particularly true for investigations prompted by reported clusters, which have the inherent danger of overestimating the disease rate through "boundary shrinkage" of the population from which the cases are assumed to have arisen. In disease surveillance the problem of making multiple comparisons can be overcome by testing for clustering and autocorrelation. When rates of disease are illustrated in disease maps undue focus on areas where random fluctuation is greatest can be minimised by smoothing techniques. Despite the fact that cluster analyses rarely prove fruitful in identifying causation, they may-like single case reports-have the potential to generate new knowledge.

Cluster Analysis↗
PubMed1996

Effects of fish oil supplementation in late pregnancy on blood pressure: a randomised controlled trial.

OBJECTIVE: To study the effect of fish oil supplementation on blood pressure during the third trimester of pregnancy. DESIGN: In the 30th week of pregnancy 533 healthy women were randomly assigned in a ratio 2:1:1 to receive fish oil (2.7 g/day n-3 fatty acids (Pikasol)), or a control regimen of either olive oil or no oil supplementation. MAIN OUTCOME MEASURES: Blood pressure measured with an automatic device (Dinamap 1846 SX, Criticon) at baseline and in weeks 33, 37, 39 and subsequently weekly until delivery. RESULTS: Mean blood pressure increased during the third trimester, and this was not influenced by group assignment. No significant effects on either systolic or diastolic blood pressure were seen in the fish oil group compared to the control groups. The proportions of women with a systolic blood pressure above 140 mmHg or a diastolic blood pressure above 90 mmHg were not significantly different in the fish oil group compared with the control groups, although the proportion of women with diastolic above 90 mmHg tended to be lower in the fish oil group compared with the olive oil group. The corresponding relative risk was RR = 0.48 (95% CI 0.22-1.06; P = 0.07). CONCLUSION: 2.7 g/day of marine n-3 fatty acids provided in the third trimester of normal pregnancy showed no effect on blood pressure.

Adult↗
PubMed1995

Erythrocyte levels compared with reported dietary intake of marine n-3 fatty acids in pregnant women.

It is well established that marine n-3 fatty acids measured in erythrocyte phospholipids of non-pregnant subjects reflect the subjects' intake of these fatty acids. In 135 pregnant women in the 30th week of gestation we compared intake of marine n-3 fatty acids and energy, estimated by a combined dietary self-administered questionnaire and interview, with fatty acids measured in erythrocyte phospholipids. Daily intake (g/d) and nutrient density of marine n-3 fatty acids (mg/MJ) correlated with the n-3 fatty acid: arachidonic acid ratio (FA-ratio) with correlation coefficients of 0.48 and 0.54 respectively. In a linear regression model with three frequency questions about marine sandwiches, marine cooked meals and fish oil as explanatory variables, and the FA-ratio as dependent variable, the multiple correlation coefficient was 0.46. Conclusions from the study were (1) levels of erythrocyte fatty acids in pregnant women may be employed as a qualitative method to rank subjects according to intake of marine n-3 fatty acids; (2) with respect to the power to explain FA-ratio variability, three simple marine food frequency questions were comparable with intake of marine n-3 fatty acids assessed by an elaborate semiquantitative dietary method involving an interview.

Adult↗
PubMed1995

Gestation length and birth weight in relation to intake of marine n-3 fatty acids.

It has been hypothesized that marine n-3 fatty acids ingested during pregnancy prolong duration of pregnancy and increase fetal growth rate in humans. By a combined self-administered questionnaire and interview applied in the 30th week of gestation we assessed dietary intake of marine n-3 fatty acids and energy in a population-based sample of 965 pregnant Danish women; in a random 14% subsample we also measured marine n-3 fatty acids relative to arachidonic acid (FA-ratio) in erythrocytes. Mean intake of marine n-3 fatty acids was 0.25 (95% range 0-0.75) g/d. We could detect no association between n-3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate.

Adult↗
PubMed1995

Essential fatty acid status in neonates after fish-oil supplementation during late pregnancy.

Healthy pregnant women (n 23) were supplemented with fish-oil capsules (2.7 g n-3 polyunsaturated fatty acids/d) from the 30th week of gestation until delivery. Subjects in a control group were either supplemented with olive-oil capsules (4 g/d, n 6) or received no supplementation (n 10). Fatty acid compositions of the phospholipids isolated from umbilical plasma and umbilical arterial and venous vessel walls were determined. Fatty acid compositions of maternal venous plasma phospholipids were determined as well. Maternal plasma phospholipids of the fish-oil-supplemented group contained more n-3 fatty acids and less n-6 fatty acids. Moreover, the amounts of the essential fatty acid deficiency markers Mead acid (20:3n-9) and Osbond acid (22:5n-6) were significantly lower. The extra amount of n-3 fatty acids consumed by the mothers resulted in higher contents of n-3 fatty acids, and of docosahexaenoic acid (22:6n-3) in particular, in the phospholipids of umbilical plasma and vessel walls. It is, indeed, possible to interfere with the docosahexaenoic acid status at birth: children born to mothers supplemented with fish oil in the last trimester of pregnancy start with a better docosahexaenoic acid status at birth, which may be beneficial to neonatal neurodevelopment.

Adult↗
PubMed1995

A clinico-pathological classification of perinatal deaths in the Faroe Islands.

OBJECTIVE: To highlight the causes of perinatal mortality in the Faroe Islands where perimortality is high according to Nordic standards. DESIGN: Two systems were employed to classify perinatal deaths on the basis of clinico-pathological findings, one focusing on obstetrical factors and the other on fetal-neonatal factors. SETTING: Faroe Islands. Data from Iceland were used for comparison since the two communities have many similarities, including similar birthweight distributions. SUBJECTS: Birth and death certificates and medical and midwife files were recovered for 98 of the 102 officially recorded perinatal deaths in the Faroes during 1977-1986. Icelandic data for 1976-1985 were available in the literature. RESULTS: The perinatal mortality rate was 13.7 per 1000 births. Obstetric factors were classified as unexplained, congenital anomaly, antepartum haemorrhage, pre-eclampsia, mechanical causes, and maternal disorders and accounted for 43%, 18%, 15%, 11%, 6% and 6% of the 98 cases, respectively. Fetal-neonatal factors were classified as antepartum asphyxia, congenital anomaly, intrapartum asphyxia, hyaline membrane disease, pulmonary immaturity, and other causes, and these factors accounted for 43%, 18%, 15%, 9%, 5%, and 8%, respectively. The excess perinatal mortality rate of 4.1 cases per 1000 births in the Faroes, relative to Iceland, could mainly be attributed to an excess of 2.9 cases per 1000 births in the group classified as unexplained, as defined according to the obstetrics classification. CONCLUSIONS: No well defined cause was particularly common in the Faroes or could account for the excess perinatal mortality rate in the Faroes relative to Iceland.

Cause of Death↗
PubMed1994

[Fish oil supplementation and duration of pregnancy. A randomized controlled trial].

It was hypothesised from previous observational studies in the Faroes and Denmark that dietary marine n-3 fatty acids would prolong the duration of pregnancy and thereby increase the birth weight, by influencing the production of prostaglandins involved in the process of parturition. Five hundred and thirty-three healthy Danish women were randomly assigned in the 30th week of pregnancy to fish oil (2.7 g n-3 fatty acids (4 1-g capsules Pikasol oil) per day), olive oil (4 1-g capsules per day) or no oil supplementation. The three groups differed in mean gestational age at birth (ANOVA, p = 0.006), with the fish oil group ranking highest and the olive oil group lowest. Babies born to women allocated fish oil had on average 4.0 (95% confidence interval 1.5;6.4) days higher gestational age and 107 (95% confidence interval 1;214) g higher weight at birth than babies born to women allocated olive oil; the difference in gestational age depended on the level of fish intake at enrollment, with a low fish intake enhancing the difference. Fish oil supplementation in the third trimester seems to prolong gestation while allowing continued growth of the foetus; this effect seems to explain the difference between the Faroes and Denmark in pregnancy duration.

Adult↗
PubMed1994

A birth weight adjusted comparison of perinatal mortality in the Faroe Islands and Denmark.

The objectives were to compare perinatal mortality (PNM) in the Faroes and Denmark while accounting for the high birth weights in the Faroes, and to discuss methodological aspects related to this task. We applied conventional methods employing absolute birth weight standards, and the Wilcox-Russell way of comparing relative birth weights. During 1977-85 perinatal mortality (PNM) in the Faroes was 14.7 (98 cases) per 1,000 births, and 1.57 times higher than that in Denmark. Conventional method: birth weight-standardised risk ratio for PNM in the Faroes v Denmark was 1.95; the risk ratio declined with increasing birth weight. Wilcox-Russell model: the risk tended to be more uniformly increased across the birth weight distribution when babies with same relative birth weights were compared; the residual component of the birth weight distribution (i.e. the excess of observed births in the lower tail beyond what could be predicted by a Gaussian distribution) was 2.1% in the Faroes and 3.6% in Denmark, which does not fit with the model assumption that the size of the residual component is a strong determinant of a population's PNM.

Birth Weight↗
PubMed1993

Effects of fish oil supplementation in the third trimester of pregnancy on prostacyclin and thromboxane production.

OBJECTIVE: Disturbance in thromboxane and prostacyclin biosynthesis has been observed in preeclampsia. We studied whether fish oil supplementation in late pregnancy interferes with maternal and fetal production of thromboxane A2 and prostacyclin I2. STUDY DESIGN: Forty-seven women in the thirtieth week of pregnancy were randomly assigned in a ratio of 2:1:1 to receive fish oil (2.7 gm of n-3 fatty acid per day [Pikasol], or either olive oil or no oil supplementation as controls. Metabolites of thromboxane A2 and A3 and of prostacyclin I2 and I3 were quantified by mass spectrometry methods in serum and urine, respectively. Maternal serum and urine were sampled at baseline, in the thirty-third and thirty-seventh weeks of pregnancy. Fetal serum was sampled at delivery. RESULTS: At the thirty-seventh week the mean concentrations of the eicosapentaenoic-derived metabolites, thromboxane B3 and prostacyclin I3, was twofold to threefold higher (p < 0.001) in the group receiving fish oil compared with combined control groups. There were no significant effects of fish oil on the prostacyclin I2 metabolite, although there was a trend toward a reduction in thromboxane B2 in this group. In umbilical cord blood the mean concentration of thromboxane B2 was lowest in the group receiving fish oil (p = 0.03). CONCLUSIONS: Fish oil was metabolized to the eicosapentaenoic acid-derived eicosanoids thromboxane A3 and prostacyclin I3 in pregnant women. Correspondingly, analog products of arachidonic acid tended to be depressed. It remains to be established whether these biochemical effects will prove beneficial in the prevention or treatment of preeclampsia and intrauterine growth retardation.

Adult↗
PubMed1993

Frequency of seafood intake in pregnancy as a determinant of birth weight: evidence for a dose dependent relationship.

STUDY OBJECTIVE: The aim was to explore whether maternal consumption of seafood is a determinant of birth weight in a dose dependent manner. DESIGN: A population based survey of lifestyle factors in pregnancy was linked with information from antenatal and obstetric records. SETTING AND PARTICIPANTS: Seventy five per cent of all 1362 women who delivered in the Faroe Islands during the study period 1986-87 who gave a structured post partum interview on lifestyle factors. MAIN RESULTS: Altogether, 2, 6, 16, 33, 26, 14, and 3% of women had consumed approximately 0, 1, 2, 3, 4, 5, and 6+ respectively seafood (fish or whale) dinner meals per week during pregnancy. The average birth weight (p = 0.02) and birth length (p = 0.002) varied significantly between the seven groups, and increased by about 0.2 kg and 1 cm, respectively between women who ate 0 and those who consumed 3 seafood meals per week. Mean birth weight and length tended to level off with further fish consumption: when fitting a second degree polynomial, the quadratic terms were negative and significant for both birth weight (p = 0.005) and length (p = 0.001). Analogous analyses for pregnancy duration were not significant, but exhibited similar trends. All analyses were adjusted for maternal height, weight, parity, age, marital status, and smoking. CONCLUSIONS: The weight and length of the newborn increased with the frequency of seafood dinner meals consumed in pregnancy but only up to a consumption level of about 3 meals per week.

Birth Weight↗