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G Norvenius

Publications and source records attributed to G Norvenius.

12 recordsLinked to original sources
PubMed1998

Sociodemographic risk factors for sudden infant death syndrome: associations with other risk factors. The Nordic Epidemiological SIDS Study.

The aim of this study was to investigate associations between sudden infant death syndrome (SIDS) and social factors in the Nordic countries. A case-control study was conducted in Denmark, Norway and Sweden: The Nordic Epidemiological SIDS Study. Parents of 244 SIDS infants and 869 control infants matched on gender, age at death and place of birth filled in questionnaires. The dataset was analysed by conditional logistic regression. In univariate analysis, the following sociodemographic factors were associated with an increased risk of SIDS: low maternal age [odds ratio (OR) 7.8; 2.8-21.5], high birth order (OR 4.4; 2.5-7.5), single motherhood (OR 2.9; 1.7-5.0), low maternal education (OR 4.5; 2.8-7.1), low paternal education (OR 3.0; 1.9-4.7), maternal unemployment (OR 2.4; 1.8-3.4) and paternal unemployment (OR 4.0; 2.7-5.9). In a multivariate analysis where maternal smoking was also included, only paternal unemployment, young maternal age and high birth order remained significantly associated with SIDS. Housing conditions were not associated with SIDS. However, the risk of SIDS was high if the family had lived in their present home for only a few years (OR 2.3; 1.3-4.1). Sociodemographic differences remain a major concern in SIDS in a low-incidence situation and even in an affluent population with adequate health services.

Case-Control Studies↗
PubMed1998

A case-control study of smoking and sudden infant death syndrome in the Scandinavian countries, 1992 to 1995. The Nordic Epidemiological SIDS Study.

AIM: To establish whether smoking is an independent risk factor for sudden infant death syndrome (SIDS), if the effect is mainly due to prenatal or postnatal smoking, and the effect of smoking cessation. METHODS: The analyses were based on data from the Nordic epidemiological SIDS study, a case-control study with 244 cases and 869 controls. Odds ratios were computed by conditional logistic regression analysis. RESULTS: Smoking emerged as an independent risk factor for SIDS, and the effect was mainly mediated through maternal smoking in pregnancy (crude odds ratio 4.0 (95% confidence interval 2.9 to 5.6)). Maternal smoking showed a marked dose-response relation. There was no effect of paternal smoking if the mother did not smoke. Stopping or even reducing smoking was beneficial. SIDS cases exposed to tobacco smoke were breast fed for a shorter time than non-exposed cases, and feeding difficulties were also more common. CONCLUSIONS: Smoking is an independent risk factor for SIDS and is mainly mediated through maternal smoking during pregnancy. Stopping smoking or smoking less may be beneficial in reducing the risk of SIDS.

Breast Feeding↗
PubMed1997

Combined effects of sleeping position and prenatal risk factors in sudden infant death syndrome: the Nordic Epidemiological SIDS Study.

OBJECTIVE: Prone sleeping is a strong risk factor for sudden infant death syndrome (SIDS). We investigated whether the combined effect of prone sleeping position and prenatal risk factors further increased the SIDS risk. METHODS: In the Nordic Epidemiological SIDS Study, parents of SIDS victims in Denmark, Norway, and Sweden completed a questionnaire on potential risk factors for SIDS. Forensic pathologists verified the SIDS diagnosis. Four controls of the same gender, age, and place of birth were selected. This matched case-control study, which included 244 SIDS cases and 869 controls from 1992 to 1995, was analyzed by conditional logistic regression. RESULTS: Odds ratios (ORs) for prone and side sleeping compared with supine sleeping for the last sleep were 13.9 (95% confidence interval 8.2-24) and 3.5 (2.1-5.7). Infants 13 to 24 weeks old had particularly high risk in prone and side sleeping, at 28.5 (7.9-107) and 5.9 (1.6-22). OR for prone sleeping was higher in girls, at 30.4 (11-88), than in boys, 10.3 (5.5-19). We found strong combined effects of sleeping position and prenatal risk factors (more than multiplicative). The OR for prone and side sleeping was increased for infants with birth weight <2500 g, at 83 (25-276) and 36.6 (13-107); for preterm infants, at 48.8 (19-128) and 40.5 (14-115); and for intrauterine growth retarded, at 38.8 (14-108) and 9.6 (4.3-22), compared with supine position in infants without these prenatal factors. The combined effect of nonsupine positions and intrauterine growth retarded was highest among 13- to 24-week-old infants. Effects of combined presence of nonsupine sleeping positions and each of the factors of smoking in pregnancy, young maternal age, higher parity, low level of maternal education, and single motherhood were more than additive. Attributable fractions in the population for prone and side sleeping were 18.5% and 26.0%. CONCLUSIONS: Both prone and side sleeping increased the risk of SIDS. The risk was increased further in low birth weight infants, preterm infants, and infants at the age of 13 to 24 weeks, suggesting that SIDS may be triggered by nonsupine sleeping in infants with prenatal risk factors during a vulnerable period of postnatal development.

Age Factors↗
PubMed1994

Microorganisms on toothbrushes at day-care centers.

The microflora on 44 toothbrushes at 4 day-care centers in the city of Göteborg have been investigated as a presumptive risk factor for transmission of microorganisms by children. Non-supervised toothbrushing without the use of toothpaste was performed at the day-care centers twice a day. Streptococci, predominantly S. salivarius, S. sanguis, and S. mitis, were the most frequently recorded group of microorganisms and generally constituted the greatest part of the flora (on average, 50%). Beta-hemolytic streptococci were not found in any sample. Haemophilus species were noted in 82% of the samples. H. parainfluenzae being the most frequent, and H. influenzae being identified in only one sample. Anaerobes constituted on average a third of the microflora. Staphylococci were identified in 86% of the samples, S. epidermidis dominating. Fungi including molds were found in 50% of the samples, and from one day-care center large numbers of enteric organisms were identified. Thus this study shows that unsupervised toothbrushing at day-care centers can be questioned, more from a general hygienic point of view than from the risk of transmitting serious pathogens.

Bacteria↗
PubMed1993

SIDS outdoors and seasonality in Sweden 1975-1987.

In order to link the reported increasing incidence of SIDS in Sweden to environmental or other risk factors, we compared birth records and circumstances of deaths in infants who died in 1975-1977 with those who died a decade later, 1985-1987. The number of liver births differed by only 6850 in these two periods. Data were acquired from autopsy records of the decreased infants and matched with their respective birth certificates which were obtained from the National Board of Health and Welfare. The reported postperinatal incidence of SIDS increased from 0.51 per 1000 in 1975-1977 to 0.93 per 1000 in 1985-1987. No significant differences in boy/girl ratio, birth weight, gestational age or age at death were found in the two periods. While the number of infants who died at night indoors in their own bed remained almost unchanged, the number of infants who died outdoors in baby carriages during the cold season increased almost four-fold. The observed increase in incidence could, to a large extent, be related to the increase in outdoor deaths. We speculate that increased incidence of smoking among young women as well as other changes in lifestyle may have been contributing factors.

Cold Temperature↗