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S E Vollset

Publications and source records attributed to S E Vollset.

At least 37 records · Page 2Linked to original sources
PubMed2001

Determinants of cobalamin status in newborns.

OBJECTIVE: Cobalamin deficiency accompanied by bone marrow dysfunction and impaired central nervous system development has been reported in infants who were born to mothers with low cobalamin intake. We investigated the relation between cobalamin status in newborns and in their healthy mothers who consumed an omnivorous diet. METHODS: Serum cobalamin and the functional markers plasma methylmalonic acid (MMA) and total homocysteine (tHcy) were determined in 173 newborns and their mothers. Forty-five children and mothers were reinvestigated after 6 weeks. RESULTS: At birth, median (interquartile range) serum cobalamin levels were 245 (175-323) pmol/L in the mothers and 314 (238-468) pmol/L in the newborns. In the neonates, serum cobalamin, but not folate, was inversely associated with MMA and tHcy. Among maternal factors, low serum cobalamin was the strongest predictor of impaired cobalamin function (defined as low cobalamin, high tHcy, or high MMA levels) in the newborns. After 6 weeks, the maternal cobalamin levels had increased (to 421 [271-502] pmol/L), whereas the newborn levels had declined (to 230 [158-287] pmol/L). In the same interval, the infants had a marked increase in plasma MMA (from 0.29 [0.24-0.38] to 0.81 [0.37-1.68] micromol/L). At 6 weeks, parity was a strong predictor of cobalamin status in the infant. CONCLUSION: The cobalamin status in the neonatal period is strongly associated with maternal cobalamin status and parity. A reduction in serum cobalamin and an increase in metabolite levels are consistent with impaired cobalamin function in a significant portion of the infants who were born to healthy, nonvegetarian mothers.

Adult↗
PubMed2001

Cod liver oil consumption, smoking, and coronary heart disease mortality: three counties, Norway.

It has been hypothesized that omega-3 fatty acid consumption may lessen the adverse effect of smoking on coronary heart disease (CHD) risk. Thus, we explored whether cod liver oil consumption was protective of coronary heart disease in a cohort of men and women participating in a cardiovascular disease screening in Norway. The study population was aged 35-54 at the time of the baseline screening conducted by the National Health Screening Service of Norway in 1977-1983. Of 56,718 age-eligible men and women, 52,138 participated, of whom 42,612 (82%) completed a dietary questionnaire. Cod liver oil use was reported by 12.5%. At baseline, cod liver oil users had lower triglycerides, adjusting for age, body mass index, time since last meal and income (p < or = .05). As of December 1992, 639 and 118 CHD deaths were observed among the men and women, respectively. Overall, we observed no effect of cod liver oil consumption reported at baseline and CHD mortality in Cox Proportional Hazards analyses [Hazard Ratio (HR) = 1.0 (0.8-1.3)]. In analyses, stratified by smoking status, never smokers and current smokers showed non-significant beneficial associations between cod liver oil use and CHD mortality (HR = 0.7, 95% CI = 0.4-1.5; and HR = 0.8, 95% CI = 0.6-1.2, respectively). However, among former smokers a non-significant excess risk of CHD mortality was associated with cod liver oil use (HR = 1.6, 95% CI = 0.9-2.6). Smokers, regardless of their cod liver oil use were at a substantially higher risk for CHD mortality relative to non-smokers. Omega-3 fatty acid supplementation, as practiced in this cohort, provided no significant benefits to CHD risk among study participants.

Adult↗
PubMed2000

Increasing mortality from amyotrophic lateral sclerosis in Norway?

OBJECTIVE: To investigate a possible increase in incidence of ALS in Norway. METHODS: Death certificate data from all deaths in Norway in the period 1961 to 1994 for ALS, PD, and MG were obtained from Statistics Norway and related to population statistics. Data on ALS was obtained on sex, age, and place of death and compared with mortality data in PD and MG for the same period. Data were standardized using the 1990 population as standard population. Poisson regression was used to test for trends in mortality. The data from the death certificates were related to a clinical study performed on ALS in one of the counties during the same period. RESULTS: The annual mortality of ALS almost doubled during the period studied, rising from 1.38 to 2.54 per 100,000 inhabitants at the end of the study. The increased mortality appeared solely in the population older than 60 years of age, with a peak in mortality in the age group 80 to 84 years. The increase was larger in women than in men, and the ratio between the sexes was 1.32 (men-women, age-adjusted at the end of the study). The mortality in patients with PD showed a similar increase to that seen in ALS, whereas no increase in mortality was observed in patients with a diagnosis of MG. There were considerable differences in ALS mortality in different counties, but no clear regional trends were observed. CONCLUSION: The authors report increasing ALS mortality. Although the increase in mortality is restricted to the population aged 65 years or older, it cannot be explained by increasing age of the general population alone.

Adolescent↗
PubMed2000

Evaluation of diagnostic tests for antinuclear antibodies in rheumatological practice.

To investigate and compare the accuracy and usefulness of diagnostic tests for antinuclear antibodies (ANA) a cross-sectional study of sera derived from patients admitted to the Department of Rheumatology was tested for the presence of ANA using either indirect immunofluorescence on HEp-2 cells, indirect immunoperoxidase techniques on HEp-2 cells and mouse kidney, or two commercial enzyme-linked immunosorbent assays (ELISA). The diagnostic sensitivity and predictive values of the tests were calculated and compared. The accuracy of tests was compared using receiver-operating characteristics (ROC) methodology. All ANA-positive sera were further analysed for the presence of antibodies against extractable nuclear antigens (anti-ENA) and anti-DNA. A moderate to good agreement was found between tests, with kappa ranging from 0.469 to 0.659. Highest sensitivity for systemic lupus erythematosus (SLE; 93.3%) and primary Sjögren's syndrome (SS; 70%) was found using immunofluorescence on HEp-2 cells. Immunofluorescence on HEp-2 cells performed statistically better than the other tests in predicting SLE but not SS. All tests except mouse kidney showed good and comparable performance in detecting sera with anti-ENA and anti-DNA. At the given cut-off values indirect immunofluorescence on HEp-2 cells performed best. All assays except mouse kidney showed performance characteristics sufficient for use in routine analysis of ANA.

Animals↗
PubMed2000

The Norwegian Arthroplasty Register: 11 years and 73,000 arthroplasties.

In 1985, the Norwegian Orthopaedic Association decided to establish a national hip register, and the Norwegian Arthroplasty Register was started in 1987. In January 1994, it was extended to include all artificial joints. The main purpose of the register is to detect inferior results of implants as early as possible. All hospitals participate, and the orthopedic surgeons are supposed to report all primary operations and all revisions. Using the patient's unique national social security number, the revision can be linked to the primary operation, and survival analyses of the implants are done. In general, the survival analyses are performed with the Kaplan-Meier method or using Cox multiple regression analysis with adjustment for possible confounding factors such as age, gender, and diagnosis. Survival probabilities can be calculated for each of the prosthetic components. The end-point in the analyses is revision surgery, and we can assess the rate of revision due to specific causes like aseptic loosening, infection, or dislocation. Not only survival, but also pain, function, and satisfaction have been registered for subgroups of patients. We receive reports about more than 95% of the prosthesis operations. The register has detected inferior implants 3 years after their introduction, and several uncemented prostheses were abandoned during the early 1990s due to our documentation of poor performance. Further, our results also contributed to withdrawal of the Boneloc cement. The register has published papers on economy, prophylactic use of antibiotics, patients' satisfaction and function, mortality, and results for different hospital categories. In the analyses presented here, we have compared the results of primary cemented and uncemented hip prostheses in patients less than 60 years of age, with 0-11 years' follow-up. The uncemented circumferentially porous- or hydroxyapatite (HA)-coated femoral stems had better survival rates than the cemented ones. In young patients, we found that cemented cups had better survival than uncemented porous-coated cups, mainly because of higher rates of revision from wear and osteolysis among the latter. The uncemented HA-coated cups with more than 6 years of follow-up had an increased revision rate, compared to cemented cups due to aseptic loosening as well as wear and osteolysis. We now present new findings about the six commonest cemented acetabular and femoral components. Generally, the results were good, with a prosthesis survival of 95% or better at 10 years, and the differences among the prosthesis brands were small. Since the practice of using undocumented implants has not changed, the register will continue to survey these implants. We plan to assess the mid- and long-term results of implants that have so far had good short-term results.

Activities of Daily Living↗
PubMed2000

Mortality after total hip replacement: 0-10-year follow-up of 39,543 patients in the Norwegian Arthroplasty Register.

We have studied the mortality after total hip replacement (THR) of 39,543 patients, having a mean age of 69 years, who were reported to the Norwegian Arthroplasty Register. The median follow-up time was 5.2 (0-10.4) years. 323 of 6201 deaths occurred during the first 60 postoperative days. The patient mortality was compared with the mortality in the Norwegian population, using standardized mortality ratios (SMR). The SMRs were compared and adjusted for age, gender, and other possible confounders in a Cox regression model incorporating the population mortality. We observed a lower mortality in patients with THR than in the Norwegian population (8-year patient mortality was 25%, versus 30% in the corresponding Norwegian population. SMR = 0.81). There was an increased standardized mortality ratio in patients less than 50 years (SMR = 2.50), patients 50-59 years (SMR = 1.16), patients with THR due to rheumatoid arthritis (SMR = 1.48), and patients with femoral neck fracture (SMR = 1.11). The SMR decreased with increasing age at the time of THR surgery. After revision surgery, the SMR was similar to that after the first primary operation, whereas a second primary operation in the opposite hip was associated with a further reduction in the SMR (SMR = 0.65). During the first 60 postoperative days, all patient categories had a higher mortality than the general population (0.8% mortality, SMR = 1.39).

Aged↗
PubMed2000

Plasma total homocysteine, pregnancy complications, and adverse pregnancy outcomes: the Hordaland Homocysteine study.

BACKGROUND: Total homocysteine (tHcy) measured in serum or plasma is a marker of folate status and a risk factor for cardiovascular disease. OBJECTIVE: Our objective was to investigate associations between tHcy and complications and adverse outcomes of pregnancy. DESIGN: Plasma tHcy values measured in 1992-1993 in 5883 women aged 40-42 y were compared with outcomes and complications of 14492 pregnancies in the same women that were reported to the Medical Birth Registry of Norway from 1967 to 1996. RESULTS: When we compared the upper with the lower quartile of plasma tHcy, the adjusted risk for preeclampsia was 32% higher [odds ratio (OR): 1. 32; 95% CI: 0.98, 1.77; P for trend = 0.02], that for prematurity was 38% higher (OR: 1.38; 95% CI: 1.09, 1.75; P for trend = 0.005), and that for very low birth weight was 101% higher (OR: 2.01; 95% CI: 1.23, 3.27; P for trend = 0.003). These associations were stronger during the years closest to the tHcy determination (1980-1996), when there was also a significant relation between tHcy concentration and stillbirth (OR: 2.03; 95% CI: 0.98, 4.21; P for trend = 0.02). Neural tube defects and clubfoot had significant associations with plasma tHcy. Placental abruption had no relation with tHcy quartile, but the adjusted OR when tHcy concentrations >15 micromol/L were compared with lower values was 3.13 (95% CI: 1.63, 6. 03; P = 0.001). CONCLUSION: Elevated tHcy concentration is associated with common pregnancy complications and adverse pregnancy outcomes.

Abruptio Placentae↗
PubMed2000

The controversy over homocysteine and cardiovascular risk.

Elevated plasma total homocysteine (tHcy) is a risk factor for occlusive cardiovascular disease (CVD). This concept is based on the observations of premature vascular disease in patients with homocystinuria, the relation between tHcy and both clinical CVD as well as preclinical atherosclerotic disease, the relation between tHcy in children and CVD in their parents or relatives, and reduction in CVD or surrogate endpoints after tHcy-lowering intervention with B vitamins. Plausible mechanisms include the in vivo interference with nitric oxide-dependent reactive vasodilatation. Some observations have raised questions about tHcy as a risk factor. 1) Some prospective studies showed a weak relation or no relation between tHcy and CVD. 2) Several traditional risk factors are associated with tHcy and may confound the relation between tHcy and CVD. 3) tHcy is related to renal function, and hyperhomocysteinemia may reflect early nephrosclerosis. 4) The C677T transition of the methylenetetrahydrofolate reductase gene causes a moderate increase in tHcy but no or only minor increased CVD risk. However, the strength of some of these arguments can be questioned because there is increasing evidence that tHcy is a proximate risk factor provoking the acute event, it strongly interacts with traditional risk factors, and it may predict CVD or death in patients with chronic renal failure. Furthermore, the studies of the C677T polymorphism lack statistical power, and the TT genotype may even modulate CVD risk independently of homocysteine. Thus, only placebo-controlled intervention studies with tHcy-lowering B vitamins and clinical endpoints can provide additional valid arguments for the debate over whether tHcy is a causal CVD risk factor.

Cardiovascular Diseases↗
PubMed2000

Knowledge and attitudes of folate, and use of dietary supplements among women of reproductive age in Norway 1998.

BACKGROUND: Authorities in many countries, including Norway from March 1998, recommend that women consume supplemental folate before and early in pregnancy to prevent neural tube defects. The aim of this survey was to establish Norwegian baseline data on knowledge, use and attitudes of folate and dietary supplements before implementing national campaigns on folate and pregnancy. METHOD: A telephone survey was carried out in late 1998 among 1,146 Norwegian women of reproductive age. The women were recruited from a nationally representative stratified random sample. RESULTS: Among the women aged 18-45 years, 50.4% had heard about folate, 32.9% knew about its role in pregnancy and 9.5% that it may prevent a malformation. Only 4.0% of the women knew that the critical period for folate supplementation to prevent a neural tube defect is before and early in pregnancy. The strongest determinants of knowledge were closeness to a pregnancy and educational level. Dietary supplements were used daily or almost daily by 53.3% of the women. The most commonly used types were multivitamin supplements and cod liver oil while only 0.9% of the women reported current use of supplemental folate. The women were also asked about use of folate and dietary supplements before or early in their last pregnancy: 44.3% reported that they had used a dietary supplement and 2.4% had used folate. Among the few women who had been pregnant within the last year of the interview, 10.3% reported use of a folate supplement. Overall, 56.0% of the women stated that they would use a folate supplement in a future pregnancy and 66.7% that they wanted more information about folate. CONCLUSIONS: Although about half of Norwegian women had heard about folate in 1998, just below 10% knew that it could prevent a malformation. Use of folate supplements was low in 1998, but more than half of the women stated that they would use folate supplements in a future pregnancy.

Adolescent↗
PubMed2000

Riboflavin as a determinant of plasma total homocysteine: effect modification by the methylenetetrahydrofolate reductase C677T polymorphism.

BACKGROUND: Plasma total homocysteine (tHcy) is a risk factor for cardiovascular disease. tHcy concentrations are partly determined by folate, cobalamin, and vitamin B(6) status, and methylenetetrahydrofolate reductase (MTHFR) and other flavoenzymes are important for the biotransformation of these vitamins. This motivates the investigation of the possible relationship between riboflavin status and tHcy. METHODS: The study had a cross-sectional design and included 423 healthy blood donors, ages 19-69 years. We determined plasma tHcy, serum folate, serum cobalamin, serum creatinine, and MTHFR C677T genotype. In addition, we measured riboflavin and its two coenzyme forms, flavin mononucleotide and flavin adenine dinucleotide, in EDTA plasma by capillary electrophoresis and laser-induced fluorescence detection. RESULTS: Riboflavin determined tHcy independently in a multiple linear regression model with adjustment for sex, age, folate, cobalamin, creatinine, and MTHFR genotype (P = 0.008). tHcy was 1.4 micromol/L higher in the lowest compared with the highest riboflavin quartile. The riboflavin-tHcy relationship was modified by genotype (P = 0.004) and was essentially confined to subjects with the C677T transition of the MTHFR gene. CONCLUSIONS: Plasma riboflavin is an independent determinant of plasma tHcy. Studies on deficient populations are needed to evaluate the utility of riboflavin supplementation in hyperhomocysteinemia.

Adult↗
PubMed1999

Impact of multiple births and elective deliveries on the trends in low birth weight in Norway, 1967-1995.

To describe trends in low birth weight (less than 2,500 g), the authors analyzed 1.7 million live births and stillbirths registered between 1967 and 1995 in the Medical Birth Registry of Norway. The proportion of low birth weight infants declined from 5.3% in 1967 to 4.5% in 1979 and was followed by a steady increase that reached 5.3% in 1995. Similar trends were observed in the proportion of preterm births. Mean birth weight increased from 3,456 g in 1967 to 3,518 g in 1995. From 1979 to 1987, the increase in the prevalence of low birth weight was related to single births, and after 1987 it was related to multiple births, which increased from 2.3% of all births in 1987 to 3.1% in 1995. The proportion of low birth weight in births occurring after 37 weeks of gestation declined continuously, resulting in low birth weight births' to an increasing extent being made up of births occurring before 37 weeks of gestation. In an ecologic analysis based on county of maternal residence, the increase in low birth weight among single births was accounted for by an increase in deliveries with induction of labor or cesarean section. The authors conclude that the overall proportion of low birth weight births is not a good indicator of health in a population with extensive use of obstetric procedures that affect gestational age or assisted fertilization, which increases the number of multiple births.

Adult↗
PubMed1999

Total homocysteine and cardiovascular disease.

Recent data have shown that an elevated plasma level of the amino acid homocysteine (Hcy) is a common, independent, easily modifiable and possibly causal risk factor for cardiovascular disease (CVD) which may be of equal importance to hypercholesterolemia, hypertension and smoking. This paper reviews the biochemical, clinical, epidemiological and experimental data underlying this conclusion and is critically questioning whether elevated tHcy is a causal factor.

Animals↗
PubMed1999

Helicobacter pylori infection and risk of cardia cancer and non-cardia gastric cancer. A nested case-control study.

BACKGROUND: Helicobacter pylori infection is an established risk factor for gastric adenocarcinoma. Potential confounding by socioeconomic factors has not been adequately assessed, and the magnitude of the relative risk in relation to gastric subsites, morphologic subtypes, sex, age, and follow-up time need further study. METHODS: We conducted a serologic case-control study nested within the Norwegian JANUS cohort. Between 1972 and 1986 serum was collected from 101,601 subjects who were followed up with regard to cancer development through 1992. RESULTS: Among 208 gastric adenocarcinoma cases, we found a strong positive association between H. pylori infection and non-cardia gastric cancer (odds ratio (OR), 5.15; 95% confidence interval (CI), 2.83-9.37), and a statistically significant negative association with cardia cancer (OR, 0.40; 95% CI, 0.20-0.77). Adjustment for socioeconomic factors and smoking did not materially alter the effect estimates. The association between the infection and non-cardia cancer was stronger for tumors distal to the angulus and tended to be stronger in women than in men. The results were similar across Laurén morphologic subtypes. CONCLUSIONS: These results strengthen the evidence of H. pylori infection as a risk factor in non-cardia gastric cancer. A negative association with H. pylori infection was found for cardia cancer.

Adenocarcinoma↗
PubMed1999

Lifestyle and cardiovascular disease risk factors as determinants of total cysteine in plasma: the Hordaland Homocysteine Study.

BACKGROUND: Plasma total homocysteine (tHcy) is a cardiovascular disease risk factor and is related to several components of the established cardiovascular disease risk profile. Cysteine is structurally and metabolically related to homocysteine, but data on its association with cardiovascular disease and cardiovascular disease risk factors are sparse. OBJECTIVE: Our objective was to search for the determinants of plasma total cysteine (tCys) and compare them with those of tHcy. DESIGN: In this cross-sectional study, we studied 7591 healthy men and 8585 healthy women aged 40-67 y with no history of hypertension, diabetes mellitus, coronary heart disease, or cerebrovascular disease. RESULTS: In the group aged 40-42 y, tCys was significantly higher in men (&mean;: 273 micromol/L; 2.5-97.5 percentile: 219-338 micromol/L) than in women (253 micromol/L; 202-317 micromol/L) (P < 0.001). In the group aged 65-67 y, there was no significant sex difference in tCys: men (296 micromol/L; 233-362 micromol/L) and women (296 micromol/L; 234-361 micromol/L). As with tHcy, tCys was positively associated with age, total cholesterol concentration, diastolic blood pressure, and coffee consumption. Body mass index was a strong determinant of tCys but was not related to tHcy. Several factors known to influence tHcy, including smoking status, folate and vitamin intake, heart rate, and physical activity, were not associated or were only weakly associated with tCys. CONCLUSION: Plasma tCys is strongly related to several factors that constitute the cardiovascular disease risk profile. This should be an incentive to determine the role of tCys in cardiovascular disease.

Adult↗
PubMed1999

The effect of hospital-type and operating volume on the survival of hip replacements. A review of 39,505 primary total hip replacements reported to the Norwegian Arthroplasty Register, 1988-1996.

We investigated associations between the survival of total hip replacements (THRs), type of hospital and annual number of THRs per hospital. The study was based on 39,505 primary THRs reported to the Norwegian Arthroplasty Register from 45 local (n 20,756), 15 central (n 12,455) and 10 university hospitals (n 6,294) during 1988-1996. The annual number of THRs was highest at central and university hospitals, both of which are training hospitals. University hospitals were further characterized by the lowest mean annual number of THRs performed per surgeon. For cemented THRs, with adjustment for gender, age, diagnosis, surgical procedure, and annual hospital volume, the revision rates at central and university hospitals were 0.8 (95% confidence interval: 0.67-0.95) and 1.2 (CI: 1.02-1.47) times that of local hospitals, respectively. A high annual number of cemented THRs per hospital was not associated with lower revision rates. In uncemented THRs, survival results were similar in central and local hospitals, whereas the adjusted revision rate at university hospitals was 1.6 (CI: 1.13-2.19) times that of local hospitals. The adjusted 6.5 year revision probability was 12% in hospitals performing < or = 10 uncemented THRs per year (n 606), 8% in hospitals performing from 18-28 operations (n 1,378) and 5% in hospitals performing > 84 operations (n 526).

Adult↗
PubMed1999

Population density and perinatal mortality in Norway and Sweden 1975-1988.

Data from the medical birth registries in Norway and Sweden were used to study geographical variations in perinatal mortality in the two countries. The study population comprised 1.4 million single births during 1975-79 and 1985-88. Perinatal death (n=9,834) for infants with a birthweight of 1,000 g or more was the main measure of outcome. In both periods and in both countries, perinatal mortality was inversely associated with population density and annual number of births, with relative risks amounting to 1.4 in Norway and 1.2 in Sweden. Among live births, these gradients were observed in deaths from asphyxia or immaturity in the first time period, and in deaths from congenital malformations in the second time period. As care for premature infants and infants with respiratory problems improves, geographical variations in perinatal mortality may to a larger extent depend on differences in medical care of infants affected by congenital malformations as well as differences in efforts to reduce the prevalence at birth of serious congenital malformations.

Birth Order↗
PubMed1998

[Folate and health--new knowledge and new recommendation].

The dietary intake of folate in Norway is not optimal with regard to minimizing the risk of birth defects (especially neural-tube defects), and poSsibly also cardiovascular diseases and other diseases. The National Nutrition Council has therefore initiated a project to evaluate the status of folate in Norway and to recommend actions for necessary improvement. A protective effect of folic acid supplements on neural-tube defects has been found in observational studies and clinical trials. The effects of folate on cardiovascular diseases and cancer are less certain. The estimated average intake of folate from foods in Norway is lower than the recommended 300 micrograms per day for adult women and men, and remarkably lower than the 400 micrograms per day recommended for pregnant and lactating women. Thus, with the aim of minimizing the risk for neural-tube defects, the National Nutrition Council now recommends that all women who are planning pregnancy or who are likely to become pregnant have an intake of at least 400 micrograms folate per day. Because it may be difficult to achieve this through diet alone, and because an additional risk-lowering effect of folic acid supplementation has been shown, a folic acid supplement of 400 micrograms per day is recommended for this group. The supplement should be taken one month before conception and during the first two months of pregnancy. Fortification of foods with folate is not recommended because some groups may then exceed the recommended upper intake level.

Adult↗