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T Bjerkedal

Publications and source records attributed to T Bjerkedal.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Physicians practicing for the legal requirements for eligibility for disability pensions].

For a person to become eligible for a disability pension in Norway the presence of illness must be confirmed by a physician. In theory, the task of confirming illness rests on scientific decision. In view of the fact that there is no formal definition of illness the definition must rest on current clinical practice. However, clinical practice, in addition to being based on present medical knowledge, is influenced by several non-medical factors such as conflicting interests associated with the various roles of the physician. This situation is illustrated by discussing underlying conflicts in consultations between doctors and patients suffering from bodily complaints but with no objective signs of disease. It is argued that eligibility for a disability pension should be dissociated from the requirement for declaration of illness.

Decision Making↗
PubMed1990

Fish-oil concentrate: effects on variables related to cardiovascular disease.

Sixty-four male, healthy volunteers aged 35-45 y were randomly assigned to receive (as 1-g capsules) either 14 g fish-oil concentrate/d (55% n-3 fatty acids) or 14 g olive oil/d for 6 wk. Plasma fibrinogen was reduced by 13% and serum triglycerides by 22% after fish-oil supplementation ended. Three weeks after supplementation ended both variables were back to baseline values. An appreciable increase in the ratio of eicosapentaenoic acid to arachidonic acid (EPA:AA) in plasma eicosapentaenoic acid to arachidonic acid (EPA:AA) in plasma and red blood cell phospholipids occurred during the fish-oil intake. High-density-lipoprotein (HDL) cholesterol and HDL2 activity tended to be lowered by fish-oil supplementation. Systolic and diastolic blood pressures, serum cholesterol, gamma-glutamyltransferase, blood glucose, and monocyte low-density-lipoprotein receptor activity did not differ significantly between the two groups. The reduction in plasma fibrinogen concentration seems of special interest because this variable in several recent studies emerges as a separate cardiovascular risk factor with a high predictive value.

Adult↗
PubMed1990

Low birthweight, congenital malformations, and spontaneous abortions among dry-cleaning workers in Scandinavia.

With a common study protocol, case-referent studies within cohorts were performed in Denmark, Norway, Sweden, and Finland to study reproductive hazards of women doing dry-cleaning work. Due to national differences not all of the studies could follow exactly the same procedures in data collection, but they were all based on the linkage of cohorts of dry-cleaning and laundry workers to national registers of births and reproductive failures. Summary measures from each study were combined without the data being pooled. The most significant finding was an increased risk of spontaneous abortion among the most exposed women in the Finnish data. This finding was only supported by the results of the other studies to a minor degree, and the combined odds ratio had confidence limits which included unity.

Abortion, Spontaneous↗
PubMed1989

Birthweight of single livebirths and weight specific early neonatal mortality in Hungary and Norway.

Comparisons of birthweights of single livebirths in Hungary and Norway reveal distributions to have similar shapes; however, in the case of Hungary the distribution is shifted to the left, i.e. towards lower weights. In the registration of pregnancy outcomes, almost identical definitions are applied in the two countries, and the observed difference in distributions of birthweights is taken to reflect that Norwegian livebirths, are on average about 300 g heavier than Hungarian livebirths. Employing the method of analysis of birthweight and perinatal mortality suggested by Wilcox & Russell, it can be demonstrated that the proportions of births in the residual distributions of birthweights in the two countries are of the same magnitude and that the relative differences in first week mortality risks are similar for all birthweights. These results are taken to support the conclusion that to use a cut-off point of 2500 g in defining low birthweight, which will result in a two fold higher proportion of such infants in Hungary compared to Norway, is unwarranted, as it will falsely convey the impression of relatively more obstetric and paediatric problems in Hungary.

Birth Weight↗
PubMed1989

Epidemiology of sickness certification--a methodological approach based on a study from Buskerud County in Norway.

This paper is part of a broader study of doctors' "sickness certification" practice, which is correlated with, but not the same as, "sickness absence" or "sickness benefits". In order to obtain a total picture, information on sickness certification must be related to the population at risk, i.e. the epidemiology of sickness certification in a total population defined geographically. There is no routine registration system that provides statistics of sickness certification in Norway. Neither is there current information about those of the population who at any one time are entitled to sickness benefits, i.e. the population at risk. The aim of the present paper is to discuss the problems of estimating annual incidences of sickness certification, and to describe the results according to patients' sex, age, and place of residence. The study is based on all "initial certificates" received at the National Insurance Offices in Buskerud county during a period of four weeks in 1985. The population at risk was estimated at 106,019 employed persons aged 16-69 years, and the annual incidence of sickness certification at 580 per 1,000 employed persons per year (females 596, males 568). The highest incidence was found in the age group 20-29 years (females 739, males 741). In the age groups 30-39 and 40-49 years, incidences were significantly higher in females than males. The standardized incidence ratio was significantly lower than average for both females and males in agricultural municipalities, while it was significantly higher than average for females 30-39 years old in urban municipalities. The basis of epidemiological studies of sickness certification used in health services planning and in community medicine is in need of improvement. This challenge is being addressed by the National Insurance Administration in association with the Central Bureau of Statistics in Norway.

Absenteeism↗
PubMed1989

Incidence of sickness certification. Proposal for use as a health status indicator.

Cause-, sex-, and age-specific incidences of sickness certification in a total population are reported. The population at risk of having a sickness certificate issued was 106,019 employed persons 16-69 years of age. The annual incidence of sickness certification was estimated at 580 per 1,000 employed persons per year (females 596, males 568). The most frequent causes of sickness certification, according to diagnostic groups, were diseases of the respiratory system, musculoskeletal/connective tissue diseases, mental disorders, and injuries. Adjusted for age, injuries were found to be less frequent causes of sickness certification among females than males (p less than 0.001), while the reverse was true for mental disorders (p less than 0.01). Among single diagnoses, "other nonarticular rheumatism" (including myalgia) was more frequent among females than males, while the opposite was true for "backpain without radiating symptoms" (p less than 0.001). Comparisons with morbidity studies indicate that diagnoses stated on initial certificates, issued to employed persons in the total population, give a reflection of a population's health problems. This suggests that sickness certification may provide a basis for a health status indicator which may prove useful in planning and evaluation of occupational health, general practice, and community health.

Adolescent↗
PubMed1989

Prevalence of psoriasis in Norway.

Information on prevalence of psoriasis was obtained from a health interview survey conducted by Central Bureau of Statistics of Norway in 1985 of a representative sample of the Norwegian population. Altogether 149 cases of psoriasis were registered in the study population of 10,576 persons, giving an overall prevalence of 1.4%, with no difference between males and females. A peak prevalence was observed in the age group 30-49 years, and a significantly lower prevalence of 0.5% was found in Hedmark and Oppland counties, as compared with the country as a whole. A higher prevalence of psoriasis among females was found in urban vis-à-vis rural areas, and in urban areas, the prevalence was higher for females than for males. No difference in prevalence was found between various socio-economic groups.

Adolescent↗
PubMed1989

Psoriatics in Norway. A questionnaire study on health status, contact with paramedical professions, and alcohol and tobacco consumption.

Information on health status, use of prescription-drugs, contact with paramedical professionals and alcohol and tobacco consumption was obtained from a health interview survey, conducted by the Central Bureau of Statistics of Norway in 1985, of a representative sample of the Norwegian population. A total of 149 cases of psoriasis were registered in the study population of 10,576 persons, giving an overall prevalence of 1.4%. Among psoriatics, 75% felt that they suffered from chronic disease, while 66% suffered from one or more diseases in addition, indicating an increased susceptibility to diseases other than psoriasis, in psoriatics. 46% of the psoriatics used prescription-drugs, indicating that in many cases both the psoriasis as well as the other disease(s) were mild or moderate, not requiring therapy. Psoriatics had few contacts with rep-resentatives of the paramedical professions. Rather, there was a tendency to turn to alcoholic drinks and in larger amounts, among psoriatics. Fewer were total abstainers, and males with psoriasis drank more frequently. Among psoriatics, daily cigarette smoking was more frequent (48%) than among non-psoriatics (36%), the difference being greatest among females.

Adolescent↗
PubMed1987

Delivery outcome among women employed in the plastics industry in Sweden and Norway.

In Sweden and Norway separate case-control studies of pregnancy outcome for the period 1973-1981 among female workers in the plastics industry were carried out with similar design. Employment records were obtained from companies producing and/or processing plastics and these were matched with the national medical birth and malformation registers. Within the cohorts of pregnancies during which the mother held employment in a plastics industry (1.397 in the Swedish and 288 in the Norwegian study), cases of stillbirths or infant deaths, selected malformations, or low birthweight (less than 2,000 g) were identified. For each case two controls from the same source were individually matched with regard to date of birth, age of mother, and parity. Exposure data concerning the 44 Swedish and ten Norwegian triplets were obtained from the employers. An increased odds ratio was found for processing of polyvinylchloride (PVC) plastics (95% CI Sweden 1.0-5.1; total material 1.1-4.5). However, processing of cold plastics yielded a higher odds ratio than processing of heated plastics. No increased odds ratio was found for processing of styrene or polyurethane plastics. Since not all of the plastics industries in the two countries participated in the studies and the number of cases was small, the result must be interpreted with caution.

Abnormalities, Drug-Induced↗
PubMed1987

Parity specific perinatal mortality. A longitudinal study based on sibships.

Perinatal mortality in sibships has been examined using the Medical Birth Registry of Norway. Using linear logistic regression, parity specific perinatal mortality in the period 1967-1981 has been analysed, controlling simultaneously for maternal age, year of birth and survival of earlier births. The risk of a perinatal loss was increased by a factor of up to 6.0 following one earlier perinatal loss, and with three earlier losses the increase was 17.0. The general reduction in mortality between the different five year periods varied according to parity and maternal age. No secular reduction in risk, however, was demonstrated in sibships where the first birth died perinatally; for some subgroups of women the risk actually increased between the first and the second five year period. The effect of maternal age changed with parity, being strong in the first birth order, but of no effect either for the third or the fourth birth orders once the perinatal survival of earlier births was controlled for. This study shows the need to take heterogeneity of risk between women into account in studies of perinatal loss; the overall improvement in perinatal mortality does not apply to every woman. As care improves, perinatal losses become less and less random, demonstrated by increased risks of recurrence.

Adolescent↗
PubMed1986

Small-for-gestational age births in successive pregnancy outcomes: results from a longitudinal study of births in Norway.

In this population-based study, a strong tendency to repeat small-for-gestational age (SGA) deliveries in successive births has been documented. Mothers who showed this tendency ('repeater mothers') differed from mothers who had only one SGA delivery in their first three single births. In the group of mothers with only one SGA birth, there was an association between the SGA birth and such pregnancy complications as preeclampsia, vaginal bleeding, and placental pathologies. No similar association with medical complications during pregnancy was found for the repeater mothers. Instead, these mothers were characterized by lower educational attainment and lower socio-economic status based on husbands' occupational groupings. Thus, the tendency to repeat SGA birth appears to be mediated in part through more adverse living conditions and lifestyle habits.

Congenital Abnormalities↗
PubMed1985

The association of parity and birth weight: testing the sensitization hypothesis.

The increase in birth weight with parity was studied in sibships of 2, 3, and 4 children using large samples from the Norwegian Birth Registry. Families with full sibs were compared to families with maternal half-sibs. The sensitization hypothesis of Warburton and Naylor predicts no increase in birth weight with parity when the mother changes mate. The hypothesis was not supported by the data, since similar increases in birth weight with parity were found in both types of families. A small effect of the sex of the first child on the birth weight of the later born children was observed.

Adult↗
PubMed1985

No significant difference in birth weight for offspring of birth weight discordant monozygotic female twins.

Birth weights of offspring of 105 female, monozygotic twin pairs discordant in birth weight were studied. No significant differences were found when offspring of the larger twin were compared with offspring of the smaller twin. The results do not support the hypothesis that in utero effects on females associated with low birth weight will influence their subsequent chance of having low birth weight offspring.

Birth Order↗
PubMed1985

A population-based study of cancer incidence in twins and in children with congenital malformations or low birth weight, Norway, 1967-1980.

The incidence of childhood cancer in twins, in children with congenital malformations diagnosed at birth, and in children of low birth weight was investigated and compared with that in the total population of Norway born live from 1967-1979. Only the malformation group had a significantly increased rate of total cancer (28.3/100,000 person-years) compared with the population (14.6/100,000). The excess cancer appeared to be limited to children with Down's syndrome or a central nervous system defect, who most frequently developed leukemia or central nervous system tumors, respectively. The rates of total cancer in children of low birth weight (9.3/100,000) and in twins (13.0/100,000) were close to expected. However, twins had a significantly increased rate of renal cancer (rate ratio = 4.1). The documented associations between cancers and congenital malformations are suggestive of some common etiologic factors which warrant further studies for their identification and for elucidating possible means of prevention.

Adolescent↗