Search PubMed⌕ Search

Biomedical subjects

Anders Ekbom

Publications and source records attributed to Anders Ekbom.

At least 73 records · Page 4Linked to original sources

[Management of asymptomatic primary hyperparathyroidism. New North American guidelines discussed from a Swedish perspective].

Primary hyperparathyroidism (HPT) is a common endocrine disease, in most cases without obvious symptoms of hypercalcemia and parathyroid hormone excess. The only curative treatment outside clinical trials is parathyroidectomy. Many patients are undiagnosed and left untreated, and the indications for curative treatment are still controversial. In 1990, NIH presented recommendations on the management of asymptomatic HPT, which was defined as HPT without symptoms and signs of renal or bone disease. Since then many studies have shed new light on mainly the cardiovascular complications and increased mortality of the disease, and the 1990 recommendations have been questioned. A workshop in 2002 revised the recommendations for handling of asymptomatic HPT in the United States. These recommendations are discussed from a Swedish perspective together with recent data on mortality in a large Swedish HPT cohort.

Adult↗

Incidence and survival of Swedish patients with differentiated thyroid cancer.

Papillary (PTC) and follicular (FTC) thyroid cancers are rare disorders but are, nevertheless, among the most common cancers in individuals below 40 years of age. From the population-based Swedish Cancer Registry we identified 3,588 individuals with PTC and 1,966 with FTC during 1958-87. Histopathology was determined by examining the original histopathology reports. The relative survival ratio (RSR) was used as the measure of patient survival. Incidence of both PTC and FTC was higher among women, especially for PTC and particularly during the fertile part of female life. Incidence of PTC increased significantly over time, a trend that was not observed for FTC. Five-year relative survival appeared to be higher for patients diagnosed with PTC compared to FTC, although this difference was almost completely explained by the confounding effect of age. Patients with PTC experience lower mortality during the period 7-20 years after diagnosis. Excess mortality was lower among women, although the magnitude of the difference varied with age and histopathology. In contrast to our perceptions based on clinical practice, we observed no difference in excess mortality between patients diagnosed with PTC and FTC during the years immediately after diagnosis (where the majority of deaths occur). Our data suggest that there may exist a subgroup of thyroid tumors with superior prognosis diagnosed in women during the fertile part of female life. Sex hormones may play a role in the etiology of these tumors.

Adenocarcinoma, Follicular↗

Age at immigration and duration of stay in relation to risk for testicular cancer among Finnish immigrants in Sweden.

Although the incidence of testicular cancer is increasing, substantial differences in incidence between countries and populations exist. These differences cannot be explained solely by genetic differences, but environmental exposures, particularly early exposures, have been implicated in the etiology of testicular cancer. To assess whether early exposures contribute to the incidence of testicular cancer, we identified 93 172 Finnish men who immigrated to Sweden between 1969 and 1996 and followed them for the occurrence of testicular cancer. The risk of testicular cancer was lower for Finnish immigrants to Sweden than for the Swedish general population (standardized incidence ratio [SIR] = 0.34, 95% confidence interval [CI] = 0.21 to 0.53). The reduced risk was associated with both seminomas and non-seminomas. Neither age at immigration nor duration of stay in Sweden had any impact on the reduced risk. Although the type of environmental exposures remains unknown, the results strongly indicate that early exposures are major determinants for testicular cancer.

Adult↗

Causes of death in patients with celiac disease in a population-based Swedish cohort.

BACKGROUND: Patients with celiac disease have an increased risk of death from gastrointestinal malignancies and lymphomas, but little is known about mortality from other causes and few studies have assessed long-term outcomes. METHODS: Nationwide data on 10 032 Swedish patients hospitalized from January 1, 1964, through December 31, 1993, with celiac disease and surviving at least 12 months were linked with the national mortality register. Mortality risks were computed as standardized mortality ratios (SMRs), comparing mortality rates of patients with celiac disease with rates in the general Swedish population. RESULTS: A total of 828 patients with celiac disease died during the follow-up period (1965-1994). For all causes of death combined, mortality risks were significantly elevated: 2.0-fold (95% confidence interval [CI], 1.8-2.1) among all patients with celiac disease and 1.4-fold (95% CI, 1.2-1.6) among patients with celiac disease with no other discharge diagnoses at initial hospitalization. The overall SMR did not differ by sex or calendar year of initial hospitalization, whereas mortality risk in patients hospitalized with celiac disease before the age of 2 years was significantly lower by 60% (95% CI, 0.2-0.8) compared with the same age group of the general population. Mortality risks were elevated for a wide array of diseases, including non-Hodgkin lymphoma (SMR, 11.4), cancer of the small intestine (SMR, 17.3), autoimmune diseases (including rheumatoid arthritis [SMR, 7.3] and diffuse diseases of connective tissue [SMR, 17.0]), allergic disorders (such as asthma [SMR, 2.8]), inflammatory bowel diseases (including ulcerative colitis and Crohn disease [SMR, 70.9]), diabetes mellitus (SMR, 3.0), disorders of immune deficiency (SMR, 20.9), tuberculosis (SMR, 5.9), pneumonia (SMR, 2.9), and nephritis (SMR, 5.4). CONCLUSION: The elevated mortality risk for all causes of death combined reflected, for the most part, disorders characterized by immune dysfunction.

Adolescent↗

Comparison of documented and recalled histories of exposure to diagnostic x-rays in case-control studies of thyroid cancer.

Most information concerning possible cancer risks attributable to lifetime exposure to diagnostic x-rays comes from studies in which x-ray history was ascertained by interview or questionnaire, but little is known about the accuracy of such information. The authors assessed agreement between medical x-ray histories obtained through interview and by review of medical records from thyroid cancer case-control studies conducted in Sweden (1985-1992; 123 cases and 123 controls) and from members of a prepaid health plan in the United States (1986-1991; 50 cases and 50 controls). In both studies, substantial disagreement was found between the numbers of x-ray examinations reported in the interview and in the medical records. There was an indication of relatively poorer reporting among controls, particularly for certain types of x-ray examinations and for large numbers of such examinations. Estimates of the risk associated with exposure to diagnostic x-rays were similar, regardless of whether interview or medical record data were used, even though ordinal dose classifications based on the two sources differed considerably. In populations with a high frequency of exposure, spurious associations with numbers of x-ray examinations or estimated thyroid dose might arise because of differences in recall. However, in the present data, reporting errors by cases and controls seemed to be largely nondifferential.

Adult↗

Abortions and breast cancer: record-based case-control study.

It has been suggested that abortions leave the breast epithelium in a proliferative state with an increased susceptibility to carcinogenesis. Results from previous studies of induced or spontaneous abortions and risk of subsequent breast cancer are contradictory, probably due to methodological considerations. We investigated the relationship between abortions and subsequent breast cancer risk in a case-control study using prospectively recorded exposure information. The study population comprised women recorded in the population-based Swedish Medical Birth Register between 1973-91. Cases were defined by linkage of the birth register to the Swedish Cancer Register and controls were randomly selected from the birth register. From the subjects' antenatal care records we abstracted prospectively collected information on induced and spontaneous abortions, as well as a number of potential confounding factors. Relative risk of breast cancer was estimated by odds ratios (OR) with 95% confidence intervals (95% CI). A reduced risk of breast cancer was observed for women with a history of at least 1 compared to no abortions (adjusted OR = 0.84, 95% CI = 0.72-0.99). The adjusted OR decreases step-wise with number of abortions to 0.59 (95% CI = 0.34-1.03) for 3 or more compared to no abortions. The patterns are similar for induced and spontaneous abortions. In conclusion, neither a history of induced nor spontaneous abortions is associated with an increased risk of breast cancer. Our data suggest a protective effect of pregnancies regardless of outcome.

Abortion, Induced↗

Risk of malignant lymphomas in patients with rheumatoid arthritis and in their first-degree relatives.

OBJECTIVE: Patients with rheumatoid arthritis (RA) are at increased risk for malignant lymphomas. Both conditions display a familial aggregation, and there are reports of RA and malignant lymphomas occurring in the same families. This study was undertaken to determine the risk of malignant lymphomas in first-degree relatives of RA patients, in order to investigate whether the increased risk of malignant lymphomas in RA could be due to genetic or environmental risk factors common to both conditions, rather than being a consequence of the rheumatic disease. METHODS: Using Swedish nationwide and population-based registers, we identified 76,527 patients hospitalized with RA in 1964-1999 and 70,290 first-degree relatives of a subset of these patients. These subjects were followed up for more than 3 decades, and information on cancer occurrence was recorded. RESULTS: Patients with RA had a significantly increased risk of malignant lymphomas (535 cases; standardized incidence ratio [SIR] 2.00, 95% confidence interval [95% CI] 1.83-2.17), which was apparent for up to 2 decades of followup. Among the first-degree relatives without RA, no increased risk of malignant lymphomas was found overall, although modest and nonsignificantly elevated risk estimates were observed in subgroups. With respect to childhood cancer (0-14 years of age), we observed an increased risk of Hodgkin's lymphoma (5 cases; SIR 3.18, 95% CI 1.03-7.42). CONCLUSION: Patients with RA are at a markedly, but possibly time-limited, increased risk for malignant lymphomas. There is little to suggest a prominent role for coinherited or common environmental risk factors in malignant lymphomas arising in the context of RA. Instead, lymphomas complicating RA appear to be a direct consequence of the inflammation or its treatment.

Adolescent↗

Lymphoma subtypes in patients with rheumatoid arthritis: increased proportion of diffuse large B cell lymphoma.

OBJECTIVE: Patients with rheumatoid arthritis (RA) have an increased risk of developing malignant lymphoma. It is not clear whether the increase is confined to certain subtypes of lymphomas. Immunosuppressive therapy and Epstein-Barr virus (EBV) have been linked to the development of these lymphomas. To gain information about the baseline pattern of lymphoma subtypes in RA before the current widespread use of immunosuppressive drugs, we examined the distribution of lymphoma subtypes and the presence of EBV in a cohort of RA patients with a low frequency and duration of treatment with immunosuppressive drugs. METHODS: By linking data from the Swedish Hospital Discharge Register and the Swedish Cancer Register, 42 cases of lymphoma were identified among 11683 patients with RA in the Uppsala Health Care Region between 1964 and 1984. The medical records and paraffin-embedded lymphoma tissues were collected, and the lymphomas were reclassified using the World Health Organization classification. In situ hybridization was used to detect EBV. RESULTS: Tissues from 35 patients were reviewed. Non-Hodgkin's lymphoma (NHL) was found in 33 patients and Hodgkin's lymphoma in 2 patients. There was an increased frequency of diffuse large B cell lymphoma (DLBCL) (22 of 33 NHL patients, 67%) compared with that in the general population (30-40%). EBV was detected in 5 of 30 examined lymphomas from patients (17%). Twenty of the 22 DLBCL patients had RA with medium or high inflammatory activity, and 6 had been treated with a disease-modifying antirheumatic drug for >or=1 year. CONCLUSION: The findings of this study suggest an increased incidence of one specific lymphoma subtype, DLBCL, in RA patients, as well as a possible association with RA disease activity.

Adult↗

Birth weight, adult height, and testicular cancer: cohort study of 337,249 Swedish young men.

OBJECTIVE: A positive association has been reported between adult height and the incidence of testicular cancer. No previous study has explored whether this relationship is due to the influence of fetal growth on adult height. METHODS: This research question was studied in a Swedish national cohort comprising 337,249 males born 1973-1980 and followed-up for a mean of 4.8 years after army medical conscription examination. Cases of testicular cancer were ascertained from the Swedish National Cancer Register. 144 cases of testicular cancer (120 non-seminomas) diagnosed after conscription were identified. RESULTS: Positive associations were found between height at age 18 years and the incidence of testicular cancer. No associations were observed between gestational age adjusted birthweight and cancer incidence. The positive association between height and cancer incidence was not attenuated in models controlling for birth weight. CONCLUSIONS: Factors influencing post-natal growth such as diet or growth related genes might underlie the association between height and cancer.

Adult↗

Appendectomy is followed by increased risk of Crohn's disease.

BACKGROUND & AIMS: Appendectomy is associated with a low risk of subsequent ulcerative colitis. This study analyzes the risk of Crohn's disease after appendectomy. METHODS: We followed-up 212,218 patients with appendectomy before age 50 years and a cohort of matched controls, identified from the Swedish Inpatient Register and the nationwide Census, for any subsequent diagnosis of Crohn's disease. RESULTS: An increased risk of Crohn's disease was found for more than 20 years after appendectomy, with incidence rate ratio 2.11 (95% confidence interval [CI], 1.21-3.79) after perforated appendicitis, 1.85 (95% CI, 1.10-3.18) after nonspecific abdominal pain, 2.15 (95% CI, 1.25-3.80) after mesenteric lymphadenitis, 2.52 (95% CI, 1.43-4.63) after other diagnoses. After nonperforated appendicitis, there was an increased risk among women but not among men (incidence rate ratio 1.37; 95% CI, 1.03-1.85, respectively, 0.89, 95% CI, 0.64-1.24). Patients operated on before age 10 years had a low risk (incidence rate ratio 0.48, 95% CI, 0.23-0.97). Crohn's disease patients with a history of perforated appendicitis had a worse prognosis. CONCLUSIONS: Appendectomy is associated with an increased risk of Crohn's disease that is dependent on the patient's sex, age, and the diagnosis at operation. The pattern of associations suggests a biologic cause.

Adolescent↗

Cancer risk in patients with hereditary hemochromatosis and in their first-degree relatives.

BACKGROUND & AIMS: Iron overload may be carcinogenic. Patients with hereditary hemochromatosis (HH) are reportedly at a 20-200-fold risk of intrahepatic cancer, but the reported risks for nonhepatobiliary cancers are conflicting. The risk of cancer in heterozygous individuals (estimated allele frequency, 1/10 to 1/20) is unknown. This study aimed to better assess these risks. METHODS: We performed a population-based cohort study of 1847 Swedish patients with HH and 5973 of their first-degree relatives using nationwide, population-based health and census registers. We used standardized incidence ratios (SIRs) as relative risk. RESULTS: With 62 liver cancers and 128 nonhepatobiliary cancers, patients with HH were at a 20-fold risk of liver cancer (SIR, 21; 95% confidence interval [CI], 16-22) but an almost unaltered risk of all other cancers (SIR, 1.2; 95% CI, 1.0-1.4), including nonelevated risks for several gastrointestinal tract cancers. At 10 years of follow-up, the absolute risk of liver cancer was 6% among men and 1.5% among women. With 21 liver cancers and 508 nonhepatobiliary cancers, first-degree relatives were at an unaltered risk of extrahepatic cancer (SIR, 1.0; 95% CI, 0.9-1.1, including unelevated risks for gastrointestinal cancers) but at a modest and historic increased risk of hepatobiliary cancer (SIR, 1.5; 95% CI, 1.0-2.4), the histopathologic spectrum of which differed from the patients. CONCLUSIONS: Patients (particularly men) with HH are at increased risk for hepatocellular cancer, although the magnitude of the risk is lower than previous estimates. Overall cancer risk in first-degree relatives does not seem to be increased.

Adolescent↗

Activation markers of connective tissue in Dupuytren's contracture: relation to postoperative outcome.

We investigated 103 consecutive patients operated on for Dupuytren's contracture (DC) to find out the relation between the expression of activation markers of connective tissue in surgical specimens obtained prospectively and recurrence of disease. The history of the disease and present state of the operated hand were obtained a mean of 4 years (range 2.5-6) after the latest operation. Immunohistochemical staining for anticollagen type IV, integrin alpha5, laminin, smooth muscle beta-actin, procollagen type I, and desmin was evaluated. Almost half of the patients noticed recurrences during the study period, one fifth within six months of operation. No differences in the expression of any of the markers investigated were found, either earlier or later than six months postoperatively, in patients with or without recurrent bending. Furthermore, there were no associations between sex, age at onset, number of operations, heredity, diabetes mellitus, or drugs taken for cardiovascular disease, and the expression of any of the immunohistochemical markers. The individual characteristics that place a person at high risk are not obviously related to ongoing production of connective tissue at the time of operation or to connective tissue activity in its conventionally-used sense.

Adult↗

Abortion rate and contraceptive practices in immigrant and native women in Sweden.

AIM: The aim of this study was to analyse whether immigrant women request induced abortion more frequently than Swedish-born women and, if so, to study possible explanations, including contraceptive practices and attitudes. METHODS: All women who requested induced abortion during a period of one year were included in the study. The 1289 women, of whom 36% were born outside Sweden, were interviewed by a nurse-midwife who, using a structured protocol, gathered information on socioeconomic factors, reasons for abortion, experience of contraceptive methods, and family planning counselling. The proportion of women with non-Swedish origin in the study population was compared with the official demographic statistics of the corresponding area. RESULTS: The number of women born outside Sweden who requested induced abortion was larger than expected from their proportion in the population. The immigrant women originated from 77 countries and four continents, the largest subgroup, 11%, coming from Iran. Immigrant women had less experience of contraceptive use, more previous pregnancies and more induced abortions than women born in Sweden. In a multivariate analysis, immigrant status and educational level were found to be independent risk factors for repeat abortion. CONCLUSION: Immigrant status seems to be an independent risk factor for induced abortion. The immigrant women originated from a wide range of cultures. There is no reason to believe that the women in this heterogeneous group should have any cultural factor in common that could explain their higher proneness to seek induced abortion. The most probable cause is that immigrant status is associated more often with low education, weak social network, poverty, unemployment, and being outside common pathways to healthcare.

Abortion, Induced↗

Motion - colonoscopic surveillance is more cost effective than colectomy in patients with ulcerative colitis: arguments against the motion.

There are insufficient data upon which to base recommendations about surveillance colonoscopy and prophylactic colectomy for the prevention of colorectal cancer in patients with ulcerative colitis. Case series, analyses of intermediate results and extrapolations from other patient groups do not constitute reliable evidence. Available studies are susceptible to several biases: the 'healthy worker' effect, surveillance bias and selection bias. Patients who are enrolled in surveillance programs are more likely to be thoroughly evaluated beforehand, are more likely to be given a diagnosis of dysplasia or neoplasm even when asymptomatic and are more likely to comply with medical treatment, including maintenance anti-inflammatory medication. Comparisons of the rates of neoplasia or death between surveyed and nonsurveyed patients are, therefore, of questionable validity. Prophylactic colectomy, unlike surveillance colonoscopy, prevents death from colorectal cancer. Moreover, it is difficult to keep patients in surveillance programs, and those who withdraw from programs appear to be at high risk of developing cancer. Prophylactic colectomy should be strongly considered for patients with dysplasia, sclerosing cholangitis, longstanding pancolitis (especially if it began early in life) or a positive family history of colorectal cancer. This procedure is underused in clinical practice and is a good alternative to colonoscopic surveillance in high risk patients.

Colectomy↗

Maternal smoking during pregnancy and appetite control in offspring.

AIMS: Intrauterine exposure to tobacco smoke products has been associated with long-term neurobehavioral effects. Modified appetite control might explain the recently observed association between maternal smoking during pregnancy and obesity in offspring. METHODS: Some 10,557 British adults aged 42 years born between 3-9 March 1958 were followed up in a birth cohort study (NCDS). The main outcome measure was self-reported poor appetite at age 42 years and main exposure was maternal smoking during pregnancy. RESULTS: The proportion of offspring with poor appetite increased with maternal smoking during pregnancy: non-smoking 4.5%; (4.0%-5.0%), medium smoking 5.6%; (4.5%-6.8%), variable smoking 6.8%; (4.9%-9.1%) and heavy smoking 7.7%; (6.3%-9.4%). The unadjusted odds ratios for maternal smoking during pregnancy (ever/never) and poor appetite is 1.49 (1.25-1.77) and after adjustment for BMI at 42 years and other potential confounding factors it is 1.22 (1.01-1.48). CONCLUSIONS: Offspring of mothers who smoked during pregnancy were more likely to report a poor appetite independent of a number of potential confounding factors. Although not in the expected direction, the results suggest maternal smoking during pregnancy may influence appetite perception through a developmental influence or through confounding by social factors.

Adult↗

Appendectomy during childhood and adolescence and the subsequent risk of cancer in Sweden.

OBJECTIVE: Researchers have speculated that surgical excision of lymphoid tissue, such as appendectomy, early in life might confer an increased risk of cancer. In this study, we determined the risks of cancer for people who had appendectomy performed during childhood. METHODS: We studied the risk of cancer in a large Swedish cohort of children who had appendectomy performed during the period of 1965-1993. Standardized incidence ratios (SIRs) were computed using age-, gender-, and period-specific incidence rates derived from the entire Swedish population as comparison. Hospital discharge diagnosis data were used to examine cancer risks by categories of surgery, medical conditions, and type of appendicitis. The average length of follow-up was 11.2 years. RESULTS: We found no excess overall cancer risk but noted a significant excess for stomach cancer (SIR: 2.45; 95% confidence interval [CI]: 1.1-4.8) and a borderline increase of non-Hodgkin's lymphoma (NHL; SIR: 1.55; 95% CI: 1.0-2.3). The elevated risks for both cancers were only evident 15 or more years after appendectomy (stomach cancer, SIR: 3.82; 95% CI: 1.7-7.5; NHL, SIR: 2.49; 95% CI: 1.4-4.2). CONCLUSIONS: It is reassuring that there was no overall increase of cancer several years after childhood appendectomy. Increased risks for NHL and stomach cancer, occurring 15 or more years after appendectomy, were based on small absolute numbers of excess cancers. As 95% of the subjects were younger than 40 years at exit, this cohort requires continuing follow-up and monitoring.

Adolescent↗