Biomedical subjects

R Bergström

Publications and source records attributed to R Bergström.

At least 19 recordsLinked to original sources

PubMed2004

Prevalence trends of obesity and overweight among 10-year-old children in western Sweden and relationship with parental body mass index.

AIM: To determine the regional prevalence, secular and family-related trends of obesity and overweight among 10-y-old children. METHODS: A cross-sectional study of 10-y-old children, born in 1990, was performed during September 2000 to June 2001 at school health centres in three communities in the western part of Sweden. Evaluation was performed in 6311 children, or 81% of the target population. Data from a cohort of children, born in 1974, who form the national growth charts, were available for comparison. RESULTS: The mean body mass index was 17.9 kg/m2 in 10-y-old children born in 1990 and 17.0 kg/m2 for 10-y-olds born in 1974 (p < 0.0001). Of the 10-y-old children in 2000-2001, born in 1990, 18% were overweight and 2.9 % obese, which corresponds to a twofold increase in presence of overweight and a fourfold increase in presence of obesity among 10-y-old children from 1984 to 2000. There was a significant correlation between parental and child body mass index. The prevalence of obesity and being overweight appeared to be higher in children whose parents did not participate in the study. CONCLUSION: During a 16-y period, from 1984 to 2000, a twofold increase in being overweight and a fourfold increase in obesity were seen among 10-y-old children in the western part of Sweden. Parental ponderosity or reluctance to participate in the study was related to a higher prevalence of being overweight or obese in the children. There is a need for the healthcare system to recognize the threats to the health of the population of this new "epidemic" and initiate preventive measures and treatment programmes.

Body Mass Index↗

PubMed2001

Trends in lung cancer incidence in Sweden with special reference to period and birth cohorts.

OBJECTIVE: Sweden has one of the largest population-based cancer registers in the world that provides an opportunity to examine the trend of lung cancer incidence during a 35-year period. The primary aim of the present study was to estimate the effects of birth cohort, year of diagnosis (period), and age on the time trends of lung cancer incidence rates, and to analyze the gender-specific incidence of different histopathological types of lung cancer. RESULTS: Among men the age-standardized incidence rate increased steadily up to 1982, when a peak of 49 cases per 100,000 person-years was reached. Among women the incidence rate was lower and showed a monotonic increase throughout the observation period. The fastest rate of increase was noted among the youngest women. In women, but not in men, there was a steady increase in risk with each successive birth cohort. For both sexes there were large changes in the histopathological distributions of cases. The most notable was a major increase in adenocarcinomas. CONCLUSIONS: The overall age-adjusted incidence rate of lung cancer in Sweden has stabilized in men during the past two decades while rates are still increasing in women. In view of the continued high prevalence of smoking among young women, a future definite increase in the overall number of lung cancer cases in women can be expected.

Adenocarcinoma↗

PubMed2000

Risk for gastric cancer after antibiotic prophylaxis in patients undergoing hip replacement.

Despite strong evidence of an association between Helicobacter pylori and gastric cancer, the benefit of eradicating H. pylori infection is unknown. Our aim was to test the hypothesis that exposure to high doses of antibiotics reduces risk for gastric cancer via possible eradication of H. pylori We conducted a nationwide case-control study nested in a cohort of 39,154 patients who underwent hip replacement surgery between 1965 and 1983. Such patients frequently receive prophylactic antibiotic treatment. During follow-up through 1989, we identified 189 incident cases of gastric cancer. For each case, three controls were selected from the cohort. Exposure data were abstracted from hospital records. Blood samples from a separate cohort undergoing hip replacement surgery were analyzed for anti-H. pylori IgG before and after surgery. Both long-term antibiotic treatment before surgery [odds ratio (OR), 0.3; 95% confidence interval (CI), 0.1-0.7] and prophylactic antibiotic treatment (OR, 0.7; 95% CI, 0.5-1.1) conferred a reduction in gastric cancer risk. The reduction appeared stronger after 5 years (OR, 0.6; 95% CI, 0.3-1.2) than during shorter follow-up after hip replacement (OR, 0.8; 95% CI, 0.4-1.7). There was an apparent decrease in risk with increasing body weight-adjusted doses of antibiotics (P = 0.13). However, the rate of H. pylori antibody disappearance was not strikingly higher in the cohort of patients undergoing hip replacement than in a control cohort. Our findings provide indirect support for the hypothesis that treatment with antibiotics at a relatively advanced age reduces the risk of gastric cancer.

Adult↗

PubMed2000

Association between medications that relax the lower esophageal sphincter and risk for esophageal adenocarcinoma.

BACKGROUND: The incidence of esophageal adenocarcinoma is increasing rapidly. Gastroesophageal reflux is a strong risk factor for this disease. The increase in incidence of esophageal adenocarcinoma coincided with the introduction of medications that promote reflux by relaxing the lower esophageal sphincter (LES), such as nitroglycerin, anticholinergics, beta-adrenergic agonists, aminophyllines, and benzodiazepines. OBJECTIVE: To test the possible association between use of LES-relaxing medications and risk for adenocarcinoma of the esophagus and gastric cardia. DESIGN: A nationwide population-based case-control study with in-person interviews. SETTING: Sweden, 1995 through 1997. PATIENTS: 189 patients with newly diagnosed esophageal adenocarcinoma, 262 with adenocarcinoma of the gastric cardia, and 167 with esophageal squamous-cell carcinoma were compared with 820 population-based controls. MEASUREMENTS: Estimated incidence rate ratios, calculated by using multivariate logistic regression from case-control data with adjustment for potential confounding. RESULTS: Past use of LES-relaxing drugs was positively associated with risk for esophageal adenocarcinoma. Among daily, long-term users (>5 years) of LES-relaxing drugs, the estimated incidence rate ratio was 3.8 (95% CI, 2.2 to 6.4) compared with persons who had never used these drugs. Drugs of all classes contributed to the increased risk, but the association was particularly strong for anticholinergics. Short-term use of other types of LES-relaxing drugs did not seem to be strongly associated with risk. The association almost disappeared after adjustment for reflux symptoms, indicating that promotion of reflux is the link between use of LES-relaxing drugs and esophageal adenocarcinoma. If 15,490 men in any age group take LES-relaxing drugs daily for 5 years, 1 additional case of adenocarcinoma would be expected (number needed to treat for harm); in men older than 60 years of age, the number needed to treat for harm is 5,570. Assuming a causal relation, about 10% of the esophageal adenocarcinomas occurring in the population may be attributable to intake of LES-relaxing drugs. Cardia adenocarcinoma and esophageal squamous-cell carcinoma were not associated with use of LES-relaxing drugs. CONCLUSIONS: The widespread use of LES-relaxing drugs may have contributed to the increasing incidence of esophageal adenocarcinoma.

Adenocarcinoma↗

PubMed2000

Observed and relative survival after aortic valve replacement.

OBJECTIVES: We sought to evaluate the effects of a number of factors that can potentially determine the optimal time for aortic valve replacement (AVR) and the observed and relative survival after the operation. BACKGROUND: Aortic valve replacement is performed in patients within a wide age span, but the proportion of elderly patients is increasing. In survival analyses, adjustment for the effects of age is therefore essential. Analysis of relative survival provides additional information on excess or disease-specific mortality and its risk factors. METHODS: Survival was analyzed in 2,359 patients (1,442 without and 917 with concomitant coronary artery bypass graft surgery) undergoing their first AVR. By relating observed survival to that expected among the general Swedish population stratified by age, gender and five-year calendar period, the relative survival and disease-specific survival were estimated. RESULTS: Early mortality after AVR (death within 30 days) was 5.6%. Relative survival rates (excluding early deaths) after 5, 10 and 15 years were 94.6%, 84.7% and 74.9%, respectively. There was an excess risk of dying during the entire follow-up period. Advanced New York Heart Association functional class, preoperative atrial fibrillation and pure aortic regurgitation were independent risk factors for observed and relative survival. Patients in the oldest age group showed decreased observed survival but excellent relative survival. CONCLUSIONS: Old age was not a risk factor for excess mortality after AVR, whereas atrial fibrillation decreased relative survival substantially.

Adolescent↗

PubMed2000

The role of tobacco, snuff and alcohol use in the aetiology of cancer of the oesophagus and gastric cardia.

While tobacco and alcohol are established risk factors for oesophageal squamous-cell carcinoma, their roles in the aetiology of the increasingly common oesophageal adenocarcinoma remains uncertain. We tested the association between tobacco, snuff and alcohol use and the risk of oesophageal and cardia cancer in a nationwide, population-based case-control study in Sweden. Face-to-face interviews were conducted with 618 (81% of all eligible) patients (189 oesophageal adenocarcinoma, 262 cardia adenocarcinoma and 167 oesophageal squamous-cell carcinoma) and 820 control subjects. Odds ratios (OR) were calculated by logistic regression with multivariate adjustments for potential confounding. The risk of oesophageal adenocarcinoma was not associated with snuff or alcohol use, and the association with smoking was weak or absent. Gastric cardia adenocarcinoma was dose-dependently associated with smoking (OR=4.2, 95% CI=2.5-7.0 among heavy smokers compared with never-smokers), but not with alcohol or snuff use. Oesophageal squamous-cell carcinoma was strongly associated with tobacco, moderately with alcohol, but not with snuff use; combined use of tobacco and alcohol entailed a strongly increased risk (OR=23.1, 95% CI=9.6-56.0 among heavy users compared with never-users). We conclude that tobacco smoking, a strong risk factor for oesophageal squamous-cell carcinoma and cardia adenocarcinoma, does not play an important role in the aetiology of oesophageal adenocarcinoma. None of the studied exposures can explain the increasing incidence of oesophageal adenocarcinoma.

Adenocarcinoma↗

PubMed2000

A multivariate analysis of factors affecting patency of femoropopliteal and femorodistal bypass grafting.

BACKGROUND: The most important factors that determine the outcome after femoropopliteal and femorodistal arterial reconstruction are still controversial. This report analysis the factors that determine the early and late patency of distal arterial reconstruction. PATIENTS AND METHODS: A retrospective analysis of patency after femorodistal arterial reconstruction with a new method for evaluation of angiographic runoff was performed for 336 arterial reconstructions. The different pre-, per- and postoperative risk factors were analysed in a Cox proportional hazards model. RESULT: The patency was significantly better for vein grafts in comparison to composite grafts and prosthetic grafts. It was 74% for vein, 46% for composite and 43% for prosthetic reconstructions, respectively, at 12 months after arterial reconstruction. The cumulative life table patency rate in extremities with good, intermediate and poor runoff was 62, 30 and 10%, respectively at 36 months. The patency rates for extremities operated on for claudication was significantly better than for extremities operated on for critical ischaemia. The multivariate analysis of different factors in a Cox analysis revealed that only the status of distal runoff, the graft material and the site of the distal anastomosis independently and significantly influenced the patency rates. CONCLUSIONS: A new model for evaluation of distal runoff proved to predict the patency rate of femoropopliteal and femorodistal arterial reconstructions reasonably well in this retrospective analysis.

Aged↗

PubMed2000

Factors affecting reproducibility of dietary reports using food frequency questionnaires.

OBJECTIVE: To study the reproducibility of a food frequency questionnaire used to assess past dietary habits. DESIGN: Repeated retrospective assessment of dietary habits of a population sample. SETTING: Uppsala-Orebro Health Care Region of Sweden. SUBJECTS: One-hundred and four subjects participating as control subjects in a case-control study on thyroid cancer. INTERVENTIONS: Between spring 1993 and spring 1994 a case-control study was conducted in the study area, in order to investigate risk factors for thyroid cancer-diet among others. The study subjects reported their consumption of selected foods with reference 1-5 y before, as well as dietary changes that occurred from adolescence to adult age. One year later 197 control persons were invited to provide a second report of the same food items. Of the invited subjects 104 agreed to participate. RESULTS: The median Spearman rank correlation coefficient between the first and second assessment was 0.58 for food consumption and 0. 56 for nutrients intake. Correlation between the two assessments varied greatly between food items, ranging from -0.03 to 0.83. The correlation was positively related to the frequency and negatively related to the skewness of consumption. The recall of dietary changes from adolescence had a median correlation coefficient of 0. 38 (range 0.19-0.69). There were hints of a higher reproducibility of dietary reports among men and among highly educated subjects (more than 11 y of education), but these differences were statistically significant only for recall of adolescent diet. Reproducibility of nutrients intake was also significantly higher among men than among women, as well as among subjects older than 45 y. CONCLUSIONS: The reproducibility of dietary reports was satisfactory. Among factors affecting reproducibility, frequency and homogeneity of consumption in the source population are presumably the most important. Age, sex and education modify the inter-subject reproducibility of past diet. Based on reproducibility of a semi-quantitative index, the recall of adolescent diet probably has a low validity. European Journal of Clinical Nutrition (2000) 54, 658-664.

Adult↗

PubMed2000

Cholecystectomy, peptic ulcer disease and the risk of adenocarcinoma of the oesophagus and gastric cardia.

BACKGROUND: Gastro-oesophageal reflux is a strong risk factor for oesophageal adenocarcinoma. Bile and pancreatic enzymes may be particularly carcinogenic. Cholecystectomy causes an increased gastric level of these constituents. A decreased risk of oesophageal adenocarcinoma has been observed in persons infected with cagA-positive Helicobacter pylori. There is a strong correlation between ulcer disease and Helicobacter pylori infection. The aim of this study was to determine whether previous cholecystectomy or peptic ulcer disease affects the risk of oesophageal carcinoma. METHODS: Data were collected as a nationwide population-based case-control study in Sweden between 1995 and 1997. Multivariate adjusted odds ratios (ORs) were calculated with logistic regression. RESULTS: There was no statistically significant association between cholecystectomy and the risk of oesophageal carcinoma. Among persons with previous peptic ulcer, the adjusted OR for oesophageal adenocarcinoma was below unity (OR = 0.6, 95 per cent confidence interval 0.3-1.1). The relative risk estimates for cardia adenocarcinoma and oesophageal squamous cell carcinoma were close to unity. CONCLUSION: Cholecystectomy, despite its effect on the composition of gastric juice, does not appear to increase the risk of adenocarcinoma of the oesophagus or gastric cardia. While the data do not contradict a protective effect of H. pylori, the results are also consistent with absence of such an effect.

Adenocarcinoma↗

PubMed2000

Long-term follow-up of morbidity and mortality after aortic valve replacement with a mechanical valve prosthesis.

AIMS: The aim of this study was to determine the incidence of valve-related complications in patients with a mechanical aortic valve prosthesis and to identify risk factors for an adverse outcome. METHODS AND RESULTS: In the 424 patients, event-free survival rates 5 and 10 years after aortic valve replacement were 62% and 37%, respectively. The linearized incidence of thromboembolic events was 4.4% per patient-year, and of anticoagulant-related haemorrhage 8.5% per patient-year. Advanced NYHA functional class, atrial fibrillation, pure aortic regurgitation and thromboembolism prior to surgery decreased event-free survival. A history of pre-operative thromboembolism increased the risk for a first embolic event after aortic valve replacement (relative hazard [RH] 3.2), but was even more strongly associated with the risk for repeated events (> or =2 events, RH 5.4). After each thromboembolic episode that occurred, the risk for a subsequent one was increased. The risk for at least one, and up to three or more haemorrhages was increased in patients with a pre-operative history of bleeding (RH 3.3-5.1) and of atrial fibrillation (RH 1.8-3.9). The risk for a subsequent event was increased by a history of repeated haemorrhages, a short interval since previous bleeding, and high age. CONCLUSIONS: There were few factors strongly related to valve related morbidity. However, previous bleedings and previous thromboembolism were powerful risk factors for repeated events.

Adolescent↗

PubMed2000

Decreasing incidence of both major histologic subtypes of gastric adenocarcinoma--a population-based study in Sweden.

While the overall incidence of gastric cancer has fallen, presumably to a large extent in parallel with Helicobacter pylori infection, the occurrence of the diffuse histologic type is thought to have remained more stable, questioning the aetiologic role of H. pylori. We have analysed the incidence of the intestinal and diffuse types separately, while considering subsite (cardia/non-cardia). With an extensive prospective effort we identified all incident cases of gastric adenocarcinoma (n = 1337) in a well-defined Swedish population (1.3 million) 1989-1994. Tumours were uniformly classified histologically and topographically. Subgroup-specific incidence rates were computed and modelled using multivariate logistic regression. Site-specific trends were clearly discrepant. The overall incidence of adenocarcinoma distal to the gastric cardia declined by 9% (95% confidence interval 6-12%) per year, while cardia cancer remained stable. Thus, the feared rise in cardia cancer could not be confirmed despite clear site-specific trend discrepancies. The intestinal type predominated, especially in high-risk areas, while diffuse tumours prevailed among young patients and women. Both main histologic types of gastric adenocarcinoma declined markedly, at similar rapidity, and with no significant trend differences between the intestinal and diffuse types, even after multivariate adjustments. Our results are consistent with an aetiologic role of environmental factors including H. pylori also for diffuse-type gastric cancers.

Adenocarcinoma↗

PubMed2000

Surgery for stomach cancer in a defined Swedish population: current practices and operative results. Swedish Gastric Cancer Study Group.

OBJECTIVE: To study routine surgical in-hospital care, and to relate postoperative morbidity and mortality to age, sex, tumour stage, operation done, and surgical workload of the hospital. DESIGN: Prospective population-based study. SETTING: All hospitals that diagnosed new cases of stomach cancer in five counties in central and northern Sweden, 1 February 1989-31 January 1995. PATIENTS: All 1024 patients diagnosed as having a new adenocarcinoma of the stomach. RESULTS: The stomach cancer was in such an advanced stage at diagnosis that only half of the patients could be offered a potentially curative operation. The tumour was resectable in 632 patients (62%). Distal gastric resection was done for 359 (57%) and total gastrectomy in 259 (41%) of all the resected cases. Postoperative complications occurred in 250 patients (31%). In multivariate analyses the relative risk (RR) for postoperative complications increased to 2.3 (95% confidence interval [CI] = 1.3 to 4.3) in patients over 79 years of age compared with those under 60. The corresponding RR for postoperative death was 5.1 (95% CI = 2.0 to 12.7) in patients over 79 years. Total gastrectomy combined with splenectomy and distal pancreatectomy carried the highest postoperative morbidity (RR = 3.3) and mortality (RR = 3.7) compared with distal gastrectomy. CONCLUSION: There was no difference in postoperative morbidity or mortality among different types of hospital categories. Surgical treatment of stomach cancer still carries a substantial morbidity and mortality in an unselected series of patients, particularly among elderly patients.

Adenocarcinoma↗

PubMed2000

No relation between body mass and gastro-oesophageal reflux symptoms in a Swedish population based study.

BACKGROUND: There is a widespread notion that obesity leads to gastro-oesophageal reflux but scientific evidence of an association is limited and inconsistent. AIMS: To estimate the strength of the association between body mass and reflux symptoms, we performed a population based cross sectional interview study. SUBJECTS: Population based, randomly selected, middle aged or elderly persons in Sweden in 1995-1997. METHODS: At face-to-face interviews we asked a stratified sample of Swedes about body measures and occurrence of reflux symptoms. Odds ratios (OR) with 95% confidence intervals (CI), calculated by logistic regression with multivariate adjustments for covariates, were the measures of association. RESULTS: Reflux symptoms occurring at least once a week more than five years before the interview were reported by 135 (16%) of the 820 interviewees. Among those who had ever been overweight during adulthood (body mass index (BMI) > or =25 kg/m(2)), the OR of having recurrent reflux symptoms was 0.99 (95% CI 0.66-1.47) compared with those who were never overweight. There was no association between BMI at age 20, BMI 20 years before the interview, or maximum adult BMI and occurrence of reflux symptoms: ORs per unit increase in BMI were 1. 00 (95% CI 0.93-1.09), 1.03 (95% CI 0.96-1.10), and 1.01 (95% CI=0.95-1.07), respectively. There was no association between BMI and severity or duration of reflux symptoms. CONCLUSIONS: Gastro-oesophageal reflux symptoms occur independently of body mass index. Weight reduction may not be justifiable as an antireflux therapy.

Adult↗

PubMed1999

Tobacco, alcohol and the risk of gastric cancer by sub-site and histologic type.

Few studies have provided information on the role of smoking and alcohol in the carcinogenesis of gastric cancer by sub-site and histologic type. The relationship of snuff dipping with risk of gastric cancer has also been rarely studied. In a population-based case-control study conducted in 5 counties of Sweden from February 1989 to January 1995, a total of 90 cases of gastric cardia cancer, 260 and 164 cases of distal gastric cancer of intestinal and diffuse types, respectively, and 1164 frequency-matched control subjects were personally interviewed about life-time smoking, use of smokeless tobacco and use of alcohol 20 years ago. Current smokers had a higher risk than never-smokers for all 3 kinds of gastric adenocarcinoma [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-3.1 for gastric cardia adenocarcinoma; OR 1.8, 95% CI 1.2-2.7 for distal gastric cancer of intestinal type; and OR 2.2, 95% CI 1.4-3.5 for distal gastric cancer of diffuse type], and the risk rose with increasing dose and duration of smoking among current smokers. However, no elevated risk was observed for ex-smokers. Neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or gastric cancer. Our study did not support the hypothesis that the role of tobacco differs by sub-site and histologic sub-type of gastric cancer.

Adenocarcinoma↗

PubMed1999

Risk of endometrial cancer following estrogen replacement with and without progestins.

BACKGROUND: Unopposed estrogen replacement therapy (i.e., estrogen without progestins) increases the risk of endometrial cancer. In this study, we examined the endometrial cancer risk associated with combined estrogen-progestin regimens currently in use, since the safety profiles of these regimens have not been clearly defined. METHODS: We conducted a nationwide population-based, case-control study in Sweden of postmenopausal women aged 50-74 years. We collected information on use of hormone replacement from 709 case patients with incident endometrial cancer and from 3368 control subjects. We used unconditional logistic regression to calculate odds ratios (ORs) as estimates of relative risks. All individual comparisons were made with women who never used the respective hormone replacement regimens. RESULTS: Treatment with estrogens alone was associated with a marked duration- and dose-dependent increase in the relative risk of endometrial cancer. Five or more years of treatment had an OR of 6.2 for estradiol (95% confidence interval [CI] = 3.1-12.6) and of 6.6 for conjugated estrogens (95% CI = 3.6-12.0). Following combined estrogen-progestin use, the association was considerably weaker than that for estrogen alone; the OR was 1.6 (95% CI = 1.1-2.4) after 5 or more years of use. This increase in risk was confined to women with cyclic use of progestins, i.e., fewer than 16 days per cycle (most commonly 10 days per cycle [OR = 2.9; 95% CI = 1.8-4.6 for 5 or more years of use]), whereas continuous progestin use along with estrogens was associated with a reduced risk (OR = 0.2; 95% CI = 0.1-0.8 for 5 or more years of use). CONCLUSION: The risk of developing endometrial cancer is increased after long-term use of estrogens without progestins and with cyclically added progestins. Continuously added progestins may be needed to minimize the endometrial cancer risk associated with estrogen replacement therapy.

Adenocarcinoma↗

PubMed1999

Association between body mass and adenocarcinoma of the esophagus and gastric cardia.

BACKGROUND: The incidence of esophageal and gastric cardia adenocarcinoma is, for unknown reasons, increasing dramatically. A weak and inconsistent association between body mass index (BMI) and adenocarcinoma of the esophagus and gastric cardia has been reported. OBJECTIVE: To reexamine the association between BMI and development of adenocarcinoma of the esophagus and gastric cardia. DESIGN: Nationwide, population-based case-control study. SETTING: Sweden, 1995 through 1997. PATIENTS: Patients younger than 80 years of age who had recently received a diagnosis were eligible. Comprehensive organization ensured rapid case ascertainment. Controls were randomly selected from the continuously updated population register. Interviews were conducted with 189 patients with adenocarcinoma of the esophagus and 262 patients with adenocarcinoma of the gastric cardia; for comparison, 167 patients with incident esophageal squamous-cell carcinoma and 820 controls were also interviewed. MEASUREMENTS: Odds ratios were determined from BMI and cancer case-control status. Odds ratios estimated the relative risk for the two adenocarcinomas studied and were calculated by multivariate logistic regression with adjustment for potential confounding factors. RESULTS: A strong dose-dependent relation existed between BMI and esophageal adenocarcinoma. The adjusted odds ratio was 7.6 (95% CI, 3.8 to 15.2) among persons in the highest BMI quartile compared with persons in the lowest. Obese persons (persons with a BMI > 30 kg/m2) had an odds ratio of 16.2 (CI, 6.3 to 41.4) compared with the leanest persons (persons with a BMI < 22 kg/m2). The odds ratio for patients with cardia adenocarcinoma was 2.3 (CI, 1.5 to 3.6) in those in the highest BMI quartile compared with those in the lowest BMI quartile and 4.3 (CI, 2.1 to 8.7) among obese persons. Esophageal squamous-cell carcinoma was not associated with BMI. CONCLUSIONS: The association between BMI and esophageal adenocarcinoma is strong and is not explained by bias or confounding. The carcinogenic mechanism, however, remains to be clarified. The increasing prevalence of obesity in western countries could be important in understanding the increasing occurrence of this tumor.

Adenocarcinoma↗

PubMed1999

Low-potency oestrogen and risk of endometrial cancer: a case-control study.

BACKGROUND: Urogenital symptoms are common among postmenopausal women. Such symptoms may be alleviated by low-potency oestrogen formulations administered orally or vaginally. Although low-potency oestrogen formulations are assumed to have few, if any, adverse effects on the endometrium, risk of endometrial neoplasia has not been quantified. METHODS: In a nationwide population-based case-control study in Sweden of endometrial cancer among postmenopausal women, we obtained detailed information on hormone replacement from 789 cases of endometrial cancer and 3368 population controls. In a histopathological review, 80 cases were reclassified as having endometrial atypical hyperplasia. Odds ratios and 95% CI were calculated with unconditional logistic regression. FINDINGS: After multivariate adjustment, oral use of oestriol 1-2 mg daily increased the relative risk of endometrial cancer and endometrial atypical hyperplasia: the odds ratios for at least 5 years of use compared with never use were 3.0 (95% CI 2.0-4.4) and 8.3 (4.0-17.4), respectively. The association was stronger for well-differentiated cancers and those with limited invasion. The excess relative risk was lost rapidly after cessation of treatment. Only weak associations were observed between vaginal application of low-potency oestrogen formulations and relative risk of endometrial neoplasia. INTERPRETATION: Oral, but not vaginal, treatment with low-potency oestrogen formulations increases the relative risk of endometrial neoplasia. Thus close surveillance of patients is needed, and addition of a progestagen should be considered.

Administration, Intravaginal↗

PubMed1999

Breast-cancer risk following long-term oestrogen- and oestrogen-progestin-replacement therapy.

While use of hormone-replacement therapy (HRT) effectively alleviates menopausal symptoms and prevents osteoporosis and possibly cardiovascular disease, there is concern of a detrimental impact on breast-cancer risk. There is a particular lack of data regarding the effect of long-term use of oestrogen-progestin combinations on breast-cancer risk. We conducted a large epidemiological study in Sweden, where combined oestrogen-progestin treatment has been predominant, to examine the influence of different regimens of menopausal hormone therapy on breast-cancer risk. In this population-based case-control study, 3,345 women aged 50 to 74 years with invasive breast cancer (84% of all eligible) and 3,454 controls of similar age (82% of all selected) were included. Mailed questionnaires and telephone interviews were used to collect detailed information on use of hormone replacement and on potential confounding factors. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through multiple logistic regression. There was a trend of increasing breast-cancer risk with duration of oestrogen/oestrogen-progestin use (OR for women treated at least 10 years, 2.43; 95% CI, 1.79-3.30, as compared to never-users), with statistically significant estimates only for women with BMI<27 kg/m2. Excess risks were observed to current use and use that ceased more than 10 years ago (OR for women treated at least 5 years, OR was 2.68, 95% CI, 2.09-3.42, and OR 2.57, 95% CI, 1.28-5.15, as compared with never-users, respectively). A positive association which was noted for use of oestrogen combined with testosterone-derived progestins appeared especially pronounced with continuously combined regimens. Long-term use of replacement oestrogens with or without progestins may substantially increase the incidence of post-menopausal breast cancer, particularly among non-obese women.

Breast Neoplasms↗