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K Magnus

Publications and source records attributed to K Magnus.

At least 19 recordsLinked to original sources
PubMed2001

Aetiology and outcome of pneumonia in human immunodeficiency virus-infected children hospitalized in South Africa.

UNLABELLED: To determine the aetiology and outcome of pneumonia in human immunodeficiency virus (HIV)-infected children, we prospectively investigated 250 children hospitalized with pneumonia who were known or clinically suspected to be HIV-positive, or who required intensive care support in Cape Town, South Africa. Blood culture, induced sputum or bronchoalveolar lavage, nasopharyngeal aspirate and gastric lavage were performed. Of the total, 151 children (60.4%) were HIV-infected. Pneumocystis carinii pneumonia (PCP), occurring in 19 (7.6%) children (15 HIV-positive), was the AIDS-defining infection in 20.3%. The incidence and type of bacteraemia (14.3%) were similar in HIV-positive and HIV-negative patients; S. pneumoniae (5%) and S. aureus (2%) were the predominant isolates. Sputum or BAL cultures yielded bacteria in 145 of 243 (60%) specimens; viruses were cultured in 37 (15.2%). Bacterial prevalence (including M. tuberculosis in 8%) and anti-microbial resistance did not differ by HIV status except for S. aureus which was more common in HIV-infected children. Thirty-one (20%) HIV-positive and 8 (8%) HIV-negative children died [RR 1.16 (95% CI 1.05-1.28), p=0.008]; using multiple logistic regression, PCP was the only risk factor for mortality (p = 0.03). CONCLUSION: In South Africa, PCP is an important AIDS-defining infection in children; bacterial pathogens occur commonly and with a similar prevalence in HIV-positive and HIV-negative children hospitalized for pneumonia. HIV-infected children with pneumonia have a worse outcome than HIV-negative patients.

Female↗
PubMed1994

Residential radon exposure and lung cancer--an epidemiological study of Norwegian municipalities.

The study is based on a collaboration between the Cancer Registry of Norway, the Norwegian Radiation Protection Authority, and National Radiological Protection Board (NRPB, UK). The association between indoor radon exposure and lung cancer was studied in 427 municipalities. NRPB detectors were sent to 10,000 households, and 7,500 of the detectors were returned. Data from a nation-wide survey of smoking habits in 1964-1965 were available. Data on asbestos exposure were also used in a regression analysis. The reporting to the Cancer Registry of all new cases of cancer is fairly complete, as hospital departments and institutes of pathology are obliged to report all cancer cases. The histologically confirmed lung cancer cases were grouped into squamous-cell carcinoma, small-cell carcinoma, adenocarcinoma and other or non-specified histological types. The age-adjusted rate of lung cancer by histological type was the dependent variable in the regression analysis. A consistent increase in incidence of lung cancer was seen with increasing tobacco consumption, but no positive trend could be shown with increasing radon exposure in the descriptive presentation of the data. In the regression analysis, however, the incidence of small-cell anaplastic lung tumors in females increased significantly with increasing radon exposure. When based on the regression coefficients, the fraction of lung cancers attributable to radon is about 2-4%. However, systematic errors cannot be excluded in an ecological study such as presented here.

Adult↗
PubMed1991

Epstein-Barr virus antibody patterns preceding the diagnosis of non-Hodgkin's lymphoma.

Immunosuppressed patients who develop non-Hodgkin's lymphoma (NHL) have abnormal antibody responses against the Epstein-Barr virus (EBV) prior to the diagnosis of malignancy. To see if this is also true of "spontaneous" cases in the general population, we undertook a collaborative serologic case-control study. From 4 serum banks containing specimens from over 240,000 persons, 104 subjects were identified for whom a blood specimen had been stored an average of 63 months before diagnosis of NHL, and 259 controls matched for age, sex, ethnic group and date of serum collection. The relative risks (RR) for subsequent development of NHL associated with elevated levels of IgG and IgM antibodies against viral capsid antigen were 2.5 (95% confidence interval = 1.1-5.7) and 3.2 (1.3-7.5), respectively; these associations increased with age at diagnosis. For the nuclear antigen, the distribution of titers for cases was more restricted than that of controls, with fewer cases having either elevated or low titers, RR = 0.5 (0.2-1.4) and 0.5 (0.2-1.2), respectively. Cases had significantly lower antibody titers against the cytomegalovirus, RR = 0.4 (0.2-0.9). These findings suggest that, at least for some patients, NHL is preceded by an enhanced level of endogenous immunosuppression with resultant EBV activation. This observation supports the role of EBV either directly in the development of NHL or as a primary marker of immune dysfunction.

Adult↗
PubMed1991

The Nordic profile of skin cancer incidence. A comparative epidemiological study of the three main types of skin cancer.

The data used for the inter-Nordic comparison of the incidence of skin cancer are based on the material of the national cancer registries of the 5 Nordic countries. It is typical of these countries that the ratio between the incidence of non-melanoma and melanoma skin cancer is much smaller than in regions near the Equator. For the detailed comparative epidemiological study of basal-cell carcinoma (BCC), squamous-cell carcinoma (SCC) and cutaneous malignant melanoma (CMM), the material from the Norwegian Cancer Registry 1955-1988 is used. The etiology of CMM has frequently been debated during recent decades. There are still some obscure points, however, particularly as regards the influence of host factors and UV exposure, and their interaction. The analysis of the incidence trend of CMM on the female breast during the time interval 1970-1988 contributes to the elucidation of these problems. Differences in the epidemiological characteristics of the 2 main types of non-melanoma skin cancer, BCC and SCC, are described. The results indicate that the effect of UV light is not a dominating for BCC as for SCC.

Adult↗
PubMed1991

Epstein-Barr virus antibody patterns preceding the diagnosis of nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) patients have elevated IgG and IgA antibody titers against the Epstein-Barr viral capsid antigen (VCA) and the diffuse component of the early antigen complex (EA-D) at diagnosis. Several studies have implied that the presence of anti-VCA-IgA can be used as a screening marker for early NPC. To evaluate this further, we undertook a serologic case-control study based on four serum banks which together had specimens from over 240,000 persons. Seven cases of undifferentiated or poorly differentiated NPC were diagnosed in the period after serum collection ranging from 26 months to 154 months. Two controls per case matched on serum bank, age, sex, race, and date of serum collection were selected by a predetermined random process. For anti-VCA-IgG, the geometric mean titer for cases (88.3) was significantly higher than that for controls (75.5, P less than 0.05). The difference was greatest among the Asian patients. No significant differences were found for anti-VCA-IgA, anti-EA-D, and anti-EA-R or anti-EBNA. No time effects were evident when titers were plotted against time of blood collection preceding diagnosis. Our results do not suggest EBV activation in the period preceding NPC diagnosis, nor that detectable IgA antibody against VCA is a marker for early disease.

Adult↗
PubMed1990

Height and weight in relation to uterine corpus cancer morbidity and mortality. A follow-up study of 570,000 women in Norway.

The height and weight of 570,000 Norwegian women, aged 30-69 years, were measured and the subjects were then followed up for 6-18 years with regard to uterine corpus cancer morbidity and mortality. The analysis reveals that both height and Quetelet's index are risk factors for uterine corpus cancer. The risk for women belonging to the 5th quintile of both height and Quetelet's index is 3.2 times higher than the risk for women in the 1st quintile of both factors. It is argued that both height and Quetelet's index express a common etiological mechanism and that this mechanism is probably connected to the early phase of the disease. Body size expressed through body surface area reveals about the same strength of association as Quetelet's index. It is calculated that if women in the 5th quintile of Quetelet's index belonged to the 4th quintile instead, there would be about 10% fewer cases of uterine corpus cancer.

Age Factors↗
PubMed1990

[Incidence and mortality of uterine cervix cancer in Norway. When do we get organized nation-wide cytologic screening in Norway?].

In 1975 and 1985 the Norwegian Ministry of Health appointed a committee to evaluate the value of cytological examination of the uterine cervix in Norway. Both committees recommended that all Norwegian women aged 20/25 to 69 should be examined every three years. The reduction in incidence of cervical cancer and the mortality from the disease has been very slight compared to the reduction in the other Nordic countries where, in contrast to Norway, organized screening has been carried out on a large scale. There are no objections to an immediate organization of a national screening programme in Norway, either from the medical or the economic point of view.

Adult↗
PubMed1989

Biological amplification factor for sunlight-induced nonmelanoma skin cancer at high latitudes.

Data for the incidence of basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) of the skin, registered for six regions of Norway during 10 years (1976-1985), were used to evaluate the biological amplification factor Ab for induction of these cancers by sunlight. Ab is the ratio of the increment in skin cancer production to the increment in causative sunlight exposure. Two different approximations were used for the action spectrum for carcinogenesis: an erythema action spectrum; and an action spectrum for mutagenesis of cells in the basal layer of the skin. These two fundamentally different approaches yielded Ab values that were similar to within about 10%: 2.1-2.3 for BCCs; and 1.6-1.8 for SCCs. Using a radiation amplification factor for ozone depletion of 0.8-1.1, we find that the total amplification factor for BCCs is within the range 1.6-2.1 and that that for SCCs is within the range 1.3-1.7 at northern latitudes of 60-70 degrees. Thus, an ozone depletion of 1% will result in an increase in the incidence of BCCs by 1.6-2.1% and of SCCs by 1.3-1.7%. There were no significant differences between the values for men and women. Neither was there any significant difference between Ab values found for skin commonly exposed to sunlight (face) and for skin sites normally covered by clothes and therefore receiving much lower exposures, in spite of the fact that the tumor density per unit skin area was a factor of 20 or more larger at the former sites. This observation, as well as the curves relating cancer incidence with annual exposure to carcinogenic sunlight, supports a power law relationship between cancer incidence and annual sun exposure. Sunlight appears to be the main cause of BCCs and SCCs even at the high latitudes of Northern Norway. All over, BCCs were found to be about 6 times more frequent than SCCs. The ratio of the incidence of BCCs to that of SCCs seemed to be independent of the latitude. Finally, BCCs were found to be equally frequent among men and women, while SCCs were found to be about twice as frequent among men as among women.

Basal Cell Carcinoma↗
PubMed1989

Hodgkin's disease and Epstein-Barr virus. Altered antibody pattern before diagnosis.

In patients with Hodgkin's disease, titers of IgG antibody against viral capsid antigen of Epstein-Barr virus and the prevalence of antibodies against early antigen are higher than expected. To evaluate whether this condition antedates diagnosis, we identified 43 persons with Hodgkin's disease, from whom blood had been drawn and stored for an average of 50.5 months before diagnosis, and 96 controls from the same populations, from whom blood had been drawn at the same time. The relative risks of Hodgkin's disease associated with elevated levels of IgG and IgA antibodies against capsid antigen were 2.6 (90 percent confidence interval, 1.1 to 6.1) and 3.7 (1.4 to 9.3), respectively. For Epstein-Barr nuclear antigen, the relative risk was 4.0 (1.4 to 11.4), and for early antigen D it was 2.6 (1.1 to 6.1). However, the prevalence of IgM antibody against capsid antigen was substantially lower in patients with Hodgkin's disease (0.22 [0.04 to 1.3]). These associations were stronger in serum samples obtained at least three years before diagnosis than in serum samples obtained closer to diagnosis. We conclude that the development of Hodgkin's disease may in some patients be preceded by enhanced activation of Epstein-Barr virus. Whether Epstein-Barr virus has a direct role in the pathogenesis of the disease or is simply a marker for a more fundamental factor affecting the immune control of latent infections is unknown.

Antibodies, Viral↗
PubMed1987

Mass screening for cervical cancer in Ostfold county of Norway 1959-77.

In 1959, the Norwegian Cancer Society started a research project in Ostfold county to assess the effect of a mass screening program for cervical cancer. The program comprised 5 screening rounds during the period 1959-77. At each screening a clinical gynecological examination was performed in addition to the cytological test. A total of 45,960 women aged 25-59 years at the first screening were invited to participate. The follow-up, which was based on the data base of the Cancer Registry of Norway, lasted until December 31, 1982. For the follow-up period as a whole, the observed incidence and mortality were reduced to 78% and 83% of the expected values, respectively. Through the initial phase of the program there was a cumulation of patients with early-stage disease, while the incidence of advanced disease and mortality were reduced. In the later part of the follow-up period, a decrease in incidence of early and advanced disease as well as in mortality was observed. Women not participating in the screening program had a significantly higher risk of cervical carcinoma than the reference population, and a less favorable stage distribution as well. Among participants in the screening program, the reduction of risk was dependent upon the number of previous negative smears. Women with 5 previous negative smears had a risk of disease which was only 18% of that expected. Problems concerning choice of reference population, migration, attendance rates, sensitivity and specificity of the cytological tests and intervals between screenings are discussed. Also, the probable conversion rates of pre-cancerous lesions to cancer and the health hazards involved in possible over-treatment of pre-cancerous cases which otherwise would have regressed, are considered. A dynamic model is suggested. In order to achieve a reduction of mortality in the short term, the efforts of the program should initially be concentrated on older women. To achieve a reduction of incidence in the long run, younger women should gradually be included. Finally, special efforts should be made to increase attendance rates among high-risk women.

Adult↗
PubMed1987

Is smoking sufficient to explain the large difference in lung cancer incidence between Finland and Norway?

In the 1960s, lung cancer among Finnish men was about 3.5 times as common as among Norwegian men. A study by Pedersen et al. in 1962 indicated that the difference in contemporary smoking habits could account for only part of the difference in lung cancer incidence in men between the countries. In that study, smoking habits in Finland and Norway were investigated via interviews of 8,700 people from six areas of each country. For the present study the Finnish and Norwegian cancer registries have followed lung cancer morbidity in those areas. When the interval between the recording of smoking habits and lung cancer incidence was 15 years, after adjustment for age and smoking habits, the Finnish males had a relative risk between 1.1 and 1.6 compared with Norwegian men. The results suggest that, given a sufficiently long latency period, almost the entire difference between Finnish and Norwegian men could be attributed to smoking habits.

Adult↗