Biomedical subjects

R Bergström

Publications and source records attributed to R Bergström.

At least 109 records · Page 6Linked to original sources

PubMed1995

Diet, bone mass, and osteocalcin: a cross-sectional study.

To determine the relationships among nutrients intake, bone mass, and bone turnover in women we have investigated these issues in a population-based, cross-sectional, observational study in one county in central Sweden. A total of 175 women aged 28-74 at entry to the study were included. Dietary assessment was made by both a semiquantitative food frequency questionnaire and by four 1-week dietary records. Dual energy X-ray absorptiometry was performed at five sites: total body, L2-L4 region of the lumbar spine, and three regions of the proximal femur. Serum concentrations of osteocalcin (an osteoblast-specific protein reflecting bone turnover) were measured by a radioimmunoassay. Linear regression models, with adjustment for possible confounding factors were used for statistical analyses. A weak positive association was found between dietary calcium intake as calculated from the semiquantitative food frequency questionnaire and total body bone mineral density (BMD) among premenopausal women. No association emerged between dietary calcium intake and site-specific bone mass, i.e., lumbar spine and femoral neck, nor was an association found between dietary calcium intake and serum osteocalcin. BMD at some of the measured sites was positively associated with protein and carbohydrates and negatively associated with dietary fat. In no previous studies of diet and bone mass have dietary habits been ascertained so carefully and the results adjusted for possible confounding factors. Neither of the two methods of dietary assessment used in this study revealed any effect of calcium intake on BMD at fracture-relevant sites among these healthy, mostly middle-aged women.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

The association of preoperative serum tumour markers with Dukes' stage and survival in colorectal cancer.

The tumour markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), TPS, CA 19-9, CA 50 and CA 242 were analysed in serum from 203 potentially curable colorectal cancer patients. The levels of all markers increased with increasing tumour stage, and all markers correlated with survival. Multivariate analyses indicated that the Dukes stage had the best prognostic explanatory power, followed by TPA. In the subset of 166 potentially cured patients, the prognostic information by the markers was substantially reduced. We conclude that preoperative serum tumour marker measurements have the potential to aid therapy selection, but also that their clinical usefulness is not immediately apparent.

Adult↗

PubMed1995

Trends in breast cancer mortality among Swedish women 1953-92: analyses by age, period and birth cohort.

Trends in breast cancer mortality among Swedish women were explored on the basis of all 51,048 deaths in women 30-89 years of age in Sweden during the period 1953-92. The age-standardised mortality rates were virtually unchanged during the observation period (with a mean of 32 deaths per 100,000 females and year), as were age-specific rates. In age-period-cohort analyses, age alone explained almost all of the variation in the rates. The effects of period and cohort were statistically significant, but very modest. Cohort effects seemed to explain more than period effects, and a weak downward trend starting with women born in 1883-92 was noted. A change in 1981 in the policy to classify the causes of death from the death certificates seemed to entail an artificial lowering of the mortality rates in women older than 75 years. It is concluded that breast cancer mortality in Sweden during the last 40 years has been remarkably stable, in spite of a substantial and constant increase in the incidence. This divergence between mortality and incidence reflects improved survival, which could in part be explained by earlier detection and more efficient treatment, or by an increasing occurrence of less aggressive tumours.

Adult↗

PubMed1995

Efficiency of organised and opportunistic cytological screening for cancer in situ of the cervix.

Cervical cancer incidence and mortality can be reduced by removal of precursor lesions detected at cytological screening. Organised screening, i.e. regular invitation of defined target groups, is generally considered more effective than opportunistic screening. The latter method however, is predominant in most settings. There is no scientific basis for advocating one type of screening or the other. Our aim was to compare the two types and to analyse their efficiency. We analysed 466,275 smears taken in an open cohort of 118,890 women during 1969-88. A computerised database permitted standardised classification of all smears and complete ascertainment of cancer in situ through record linkage. The number of in situ cancers detected per 1000 smears, the detection ratio, was used as an outcome measure both in univariate analyses and in multivariate logistic regression models. Cancer in situ was detected in 1076 women in the study cohort, with a detection ratio of 3.0 at organised and 2.1 at opportunistic screening, yielding an unadjusted odds ratio of 0.69 (95% CI 0.61-0.79). After adjustment for age and time period, the probability of detecting cancer in situ was around 25% higher with opportunistic than with organised screening (OR = 1.26; 95% CI 1.09-1.46). This difference in favour of opportunistic screening was most pronounced in the first 10 year period and disappeared during the last decade. The difference in efficiency between organised and opportunistic screening in the detection of cancer in situ was slight, if any. The dogma that organised screening is significantly more efficient than the opportunistic type needs reconsideration.

Adult↗

PubMed1995

Diet and hip fracture risk: a case-control study. Study Group of the Multiple Risk Survey on Swedish Women for Eating Assessment.

BACKGROUND: The role of diet as a risk factor for osteoporotic fractures is unclear. Earlier studies have yielded conflicting results. METHODS: In two counties in central Sweden we investigated the association between dietary intake and the risk of proximal femoral fractures in a case-control study nested in a cohort. Women born in 1914-1948 were asked to fill out a food frequency questionnaire when invited to attend for mammographic screening between the years 1987 and 1990. More than 65,000 women completed the questionnaire. Those who had participated in the enquiry and subsequently sustained a first hip fracture were defined as cases. For every case, four individually matched controls, by age and county of residence, were selected from the cohort. A second questionnaire concerning confounding factors was mailed to controls and cases. In all, 247 cases and 893 controls could finally be included. Monthly intake of foods and daily intake of nutrients were calculated. RESULTS: When highest quartile of intake was compared to lowest, intakes of iron (adjusted odds ratio [OR] of 3.3, 95% confidence interval [CI]: 1.6-6.9), magnesium (adjusted OR = 2.7, 95% CI: 1.3-6.0) and vitamin C (adjusted OR = 1.9, 95% CI: 1.2-3.1) were found to be independent risk factors for hip fracture. High calcium intake did not protect against hip fracture. Smoking, low physical activity in leisure time, low body mass index, earlier fracture of the distal forearm and diabetes were all risk factors while postmenopausal hormone replacement therapy protected against hip fracture. DISCUSSION: This large study indicates new dietary risk factors for hip fracture. The association between high dietary intake of iron, magnesium and vitamin C and risk of hip fracture has not been reported previously. Further clinical and experimental studies are needed to confirm these findings and to investigate their mechanism of action.

Adult↗

PubMed1995

p53 and Rb immunostaining in locally advanced bladder cancer: relation to prognostic variables and predictive value for the local response to radical radiotherapy.

The association between known prognostic variables and altered immunostaining for the nuclear proteins retinoblastoma (Rb) and p53 was studied in a homogeneous series of locally advanced bladder cancer. The predictive value of this immunostaining for the local response to intended radical radiotherapy was investigated. Among 262 patients treated with intended radical radiotherapy between 1967 and 1986, a total of 154 patients were evaluable with respect to local response to treatment. The paraffin-embedded specimen from the tumour prior to irradiation was immunostained with the monoclonal antibodies PMG3-245 for Rb and 1801 for p53 nuclear proteins after heating in a microwave oven for 40 min at 650 W. An altered expression of Rb and p53 was observed in 18 and 42% of the tumours, respectively. p53 overexpression was associated with higher tumour grade. However, the results of the p53 and Rb immunostaining procedures had no predictive value for tumor response to radiation treatment, local control or cancer-specific mortality.

Adult↗

PubMed1995

Improved control of invasive cervical cancer in Sweden over six decades by earlier clinical detection and better treatment.

PURPOSE: Cancer of the cervix uteri can be controlled by cytologic screening for the detection of precursor lesions, but such intervention remains unrealistic in many countries in which this cancer is common. The possibility of reducing mortality by earlier clinical detection, followed by basic therapy, has never been properly assessed. PATIENTS AND METHODS: We compiled records of incident cases of invasive cancer of the cervix diagnosed in a defined area of Sweden from 1930 through 1990. In a cohort of 6,044 women, we analyzed temporal trends in incidence and survival by clinical stage and age at diagnosis. Generalized proportional hazards models were used to study several factors simultaneously and quantify the overall reduction in mortality. RESULTS: For each successive stage at diagnosis, the overall risk of dying increased 2.5-fold (95% confidence interval [CI], 2.4 to 2.7). From 1930, a marked improvement in stage distribution was accompanied by increasing survival rates in stages I and II disease. These changes largely took place before the introduction of screening and external-beam radiation. The 10-year relative survival rate increased from 33% in the 1930s to approximately 55% in the 1950s and thereafter. CONCLUSION: Improvements in public and professional awareness of cervical cancer resulted in diagnoses at earlier clinical stages. The rate of cure in early stages improved when basic local treatment was introduced, but only little of the progress was attributable to the introduction of more advanced treatment technologies. These findings offer considerable hope for a substantial reduction in the mortality of cervical cancer without cytologic screening, even in countries with limited resources.

Adult↗

PubMed1995

The value of prostate specific antigen in early diagnosis of prostate cancer: the study of men born in 1913.

PURPOSE: We attempt to elucidate the performance of serum prostate specific antigen (PSA) as a screening test for prostate cancer. MATERIALS AND METHODS: We analyzed sera stored since 1980 in a nested case-control study. RESULTS: The 36 patients with prostate cancer had a markedly greater mean serum PSA level than did 68 subjects without cancer (22.71 versus 2.67, respectively, p < 0.0001). Among the controls 24% had a serum PSA of greater than 4.0 micrograms/l. A serum PSA value exceeding 4.0 micrograms/l. in 1980 was associated with a 20-fold excess risk of cancer between 1981 and 1986, and an 8-fold risk between 1987 and 1991. CONCLUSIONS: Diagnosis of clinically significant prostate cancer can be advanced substantially by serum PSA testing. However, the large number of high serum PSA values in men who remained free of clinical disease emphasizes the need for a more specific screening test.

Aged↗

PubMed1994

Radiocaesium transfer to man from moose and roe deer in Sweden.

Studies of radiocaesium in the forest ecosystems in Sweden resulted in aggregated transfer factors quantified for the transfer of 137Cs from soil to moose and roe deer. These aggregated transfer factors were 0.02 m2 kg-1 for moose and 0.05 m2 kg-1 for roe deer. There seems to be no decrease in the 137Cs activity concentrations in moose harvested in our research area and therefore we suggest the use of the physical half-life of 137Cs (30 years) as the effective ecological half-life. The time-integrated transfer of 137Cs from the Chernobyl fall-out to man by moose in Sweden was calculated and found to be 115 GBq, corresponding to 1500 man Sv for moose. The time-integrated transfer by roe deer to man was estimated to be between 25-48 GBq, corresponding to 327-620 man Sv for roe deer. The annual transfer of 137Cs to man by moose has varied between 2.0-2.7 GBq, corresponding to 27-34 man Sv. Depending on the group studied, the mean annual transfer of 137Cs can be calculated to be from about 250 to 43,000 Bq. For example, the mean annual transfer of 137Cs by moose to hunters and their families in Gävle commune, the most affected commune in Sweden, was estimated to be about 26,000 Bq, corresponding to 0.34 mSv.

Animals↗

PubMed1994

Testicular cancer in nine northern European countries.

The incidence of testicular cancer was examined in the Nordic and Baltic countries, Poland and Germany by collaboration among 10 cancer registries. Population-based registers were used to analyze a total of 34,309 cases, diagnosed from the start of registration (varying from 1943 in Denmark to 1980 in Latvia and Lithuania) through 1989. An approximately 10-fold geographical variation was found in 1980, with the highest age-standardized incidence rate (7.8 per 10(5); world standard population) in Denmark and the lowest (0.9) in Lithuania. During the entire period of registration, incidence increased rapidly in all countries, by 2.3 to 3.4 per cent annually in the Nordic countries and by about 5 per cent in Poland and Germany; there was some evidence of a slower increase in Denmark and Poland after 1975. The rising trend was more pronounced for ages below 30. The age-specific incidence peaked in all countries at ages 25 to 34, but the geographical variation was considerable. Our data indicate that environmental influences on testicular cancer are strong. Exposure to causal factors mostly takes place early in life, shows substantial geographical variation, and increases over time, so that the age-standardized incidence doubles every 15 to 25 years. New aetiological hypotheses are needed to accommodate these salient features of the descriptive epidemiology, since risk factors considered so far cannot explain the observed pattern.

Adolescent↗

PubMed1994

Diet and breast cancer risk. Results from a population-based, case-control study in Sweden.

BACKGROUND: We describe an epidemiologic analytical study of the relationship between current diet and breast cancer risk. METHOD: The study design is a case-control analysis. Cases were recruited from a mammography screening program used within the national health care system; the control subjects were selected from subjects free of breast cancer in the same population. A total of 380 cases and 525 control subjects, frequency-matched for age, month of mammography, and county of residence, were identified. Of these, 265 cases and 432 control subjects were included in this analysis. Odds ratios for breast cancer in relation to food and nutrient intake were the main outcome measures. RESULTS: Exposure in the highest quartile of beta-carotene intake gave an odds ratio of 0.6 (95% confidence interval, 0.4 to 1.0). No increased risk was noted with high fat intake. Breast cancer risk was associated with alcohol intake only when alcohol was analyzed in quartiles: odds ratio, 1.6 (95% confidence interval, 1.0 to 2.4) for the highest quartile of intake vs the lowest. Stratified analyses showed that a high fat intake might decrease the protective effect of beta-carotene intake. Risks did not change appreciably with adjustment for total energy intake or known breast cancer risk factors. CONCLUSIONS: As in most other studies, no strong risk factors for breast cancer have been identified in the current diet. The negative association between breast cancer risk and beta-carotene intake may be supported by a plausible mechanism, but our finding concerning alcohol should be interpreted cautiously since there was no dose-response relationship and the biological mechanism for a threshold effect at very low levels of consumption is unclear.

Adult↗

PubMed1994

Nutrients and gastric cancer risk. A population-based case-control study in Sweden.

A population-based case-control study of gastric cancer was conducted in areas with contrasting incidence rates in Sweden. Face-to-face interviews were carried out with 338 (74.1%) of all eligible cases and 679 (77.3%) of the selected controls. Consumption of selected nutrients during adolescence and 20 years prior to interview was estimated, together with life-time intake of vitamin supplements. Ascorbic acid and beta-carotene had an unequivocal protective effect, but alpha-tocopherol and nitrate were also negatively associated with gastric-cancer risk. In a multivariate analysis including all of these factors, only ascorbic acid remained a significant protective factor. The only macronutrient positively associated with the risk of gastric cancer was fat: intake 20 years prior to interview, but not during adolescence, was found to have a significant impact. Supplementation with vitamins almost halved the risk after adjustment for dietary intake of the corresponding vitamins. While the protective effect of vitamin C and beta-carotene could conceivably be ascribed to other agents in the diet, the strong negative association between supplementation with vitamin C and risk of gastric cancer supports the hypothesis of a protective role of this anti-oxidant.

Age Factors↗

PubMed1994

Clinical and histopathologic predictors of survival in patients with malignant melanoma: a population-based study in Sweden.

BACKGROUND: Previous malignant melanoma studies regarding prognostic factors have often selected their patients from hospitals. Unfortunately, most of these studies have had small numbers of patients, consisted of short-term data sets, omitted important factors, did not optimize histopathologic classification, had too short or inadequate follow-up, and did not test their predictive models. PURPOSE: Our study goals were to identify independent clinical and histopathologic determinants of survival in malignant melanoma, to analyze changes in prognostic value over follow-up time, and, finally to construct a prognostic index. METHODS: A random sample from the Swedish Cancer Registry of the records of 498 (246 men and 252 women) patients defined by gender, five 5-year time periods of diagnosis from 1960 through 1984, and five anatomic sites formed the cohort on whom data were analyzed by univariate analyses. Multivariate analyses were based on data on 476 patients with complete information about all variables. All patients in the cohort had complete follow-up through December 31, 1989. Clinical information was abstracted and recorded as: date of diagnosis, stage at diagnosis, sex, age, anatomic site of primary tumor, date of death, and cause of death. Histopathologic slides were re-examined and classified with regard to histogenetic type, level of invasion, tumor thickness, ulceration, vascular invasion, regression, lymphocytic reaction, pre-existing nevus, and cell type. RESULTS: All variables, except pre-existing nevus and cell type, were significant predictors of survival. In the multivariate analyses including all variables, women still had a significant, 33% lower relative hazard than men. The prognosis was poor in the youngest age group. Patients with external ear, scalp-neck, and trunk-located melanoma had increasing relative hazard when all variables were included. Regional metastases and tumor thickness remained independent prognostic factors. No significant association between histogenetic type or level of invasion persisted. Patients whose tumors showed ulceration or vascular invasion had lower relative hazard when all variables were included. Level of invasion, tumor thickness, ulceration, and vascular invasion were significantly associated with the prognosis during both short- and long-term follow-up. The patients were subgrouped according to percentage fractions of their score on the prognostic index. Survival curves for these groups of patients were well separated, thus identifying patients with a low or high risk of death from malignant melanoma. CONCLUSION: The present population-based study identifies independent clinical and histopathologic predictors of survival in cutaneous malignant melanoma and emphasizes the role of histopathologic characteristics such as tumor thickness, ulceration, and vascular invasion besides anatomic site.

Adult↗

PubMed1994

Tobacco, alcohol and the risk of gastric cancer. A population-based case-control study in Sweden.

Previous studies have provided conflicting information on the role of tobacco and alcohol in gastric carcinogenesis. A population-based case-control study with 338 histologically confirmed gastric-cancer cases and 679 control subjects was conducted. Information relating to life-time tobacco consumption, alcohol intake and diet during adolescence and 20 years before interview, and to socio-economic conditions was obtained through face-to-face interviews. Current cigarette smokers were found to have a greater risk than non-users of tobacco. The duration of cigarette or pipe smoking was positively associated with gastric-cancer risk. There was significant interaction between tobacco use and fruit consumption. High fruit intake was more protective among users of tobacco than among non-users, and the risk estimates associated with cigarette smoking were higher among those with low fruit consumption than among frequent fruit-eaters. Likewise, though to a lesser extent, vegetable intake interacted with tobacco use. Snuff dipping and alcohol intake was not associated with gastric-cancer risk. However, high alcohol intake tended to increase the risk associated with tobacco use. This study adds further support to the role of tobacco smoking in gastric carcinogenesis, and demonstrates that high intake of fruits and vegetables may be particularly beneficial in smokers.

Adult↗

PubMed1994

Early-life risk indicators of gastric cancer. A population-based case-control study in Sweden.

Exposures early in life seem to play an important role in the development of gastric cancer, but their nature is not well understood. In a population-based case-control study, we examined weight, height and body-mass index (BMI) at the age of 20 as well as indices of socioeconomic conditions. Face-to-face interviews were conducted with 338 of 456 eligible histologically confirmed gastric cancer patients and 679 of 880 eligible control subjects, sampled from population registers and frequency matched by age and gender. Gastric cancer risk was negatively associated with height. Risk was positively, associated with weight at age 20 in both sexes. The highest BMI-quartile was associated with an increased risk. This association between BMI and risk was confined to BMI at age 20, and disappeared for BMI 20 years prior to interview. High socioeconomic status (SES) as well as long education carried a decreased risk of gastric cancer. Number of siblings was positively associated with risk. Factors related to short stature and high adolescent body weight are associated with an increased risk of gastric cancer, as is a high number of siblings. These factors may reflect influences of dietary patterns early in life.

Adolescent↗

PubMed1994

Risk factors for oesophageal cancer in northeast China.

A hospital-based case-control study of oesophageal cancer was carried out in the Heilongjiang Province, a low-risk area for oesophageal cancer in China. From May 1985 to May 1989, 196 histologically confirmed cases and 392 controls with other (non-neoplastic) diseases were personally interviewed in the wards of 5 major hospitals. Information was obtained about usual consumption in the early 1980s of 32 major contributors to the diet in the province, socio-demographic status, smoking and alcohol consumption. Odds ratios (OR) were obtained from logistic regression models, and confounding was controlled by means of multivariate models. Smoking and alcohol consumption were major risk factors for oesophageal cancer in this population. Smokers of handmade cigarettes exhibited a particularly high risk. A near multiplicative synergism was found between smoking and alcohol consumption. There was a significant inverse dose-risk trend for combined consumption of vegetables and fruits; a 300-g increase per day lowered risk by 35%. Vitamin C intake was negatively associated with risk; a 100-mg increase per day lowered risk by 39%. Our data suggest a modifying effect of vitamin C and beta-carotene on risk associated with smoking, but the power of analyses was low. Salt, salt-preserved foods and pickled vegetables were not associated with increased risk. High temperature of meals and drinks was a strong risk indicator in this population. The strength of tea and overall tea consumption were independent determinants of the risk.

Adult↗

PubMed1994

Survival trend after invasive cervical cancer diagnosis in Sweden before and after cytologic screening. 1960-1984.

BACKGROUND: Cytologic screening can reduce mortality from cervical cancer by detection and removal of premalignant lesions. Conceivably, mortality is further reduced because more women with invasive disease are diagnosed at an earlier, curable stage. This hypothesis can be assessed in Sweden, where population-based screening programs were introduced successively over about a decade starting in 1964. METHODS: Record linkages permitted complete follow-up through 1986 of all 17,377 patients with invasive cervical cancer diagnosed in Sweden from 1960 through 1984. We analyzed relative survival rates that describe the survival of patients after elimination of the effects of causes of death other than cancer of the cervix. RESULTS: Prognosis improved substantially in patients younger than age 50 years at diagnosis; from 1960-1964 to 1980-1984, the 5-year relative survival rate increased from 69.8% to 88.8% at age 20-29 years, from 71.7% to 85.5% at age 30-39 years, and from 68.6% to 77.9% at age 40-49 years. The excess mortality was thus reduced by more than half in patients diagnosed when younger than 40 years. In contrast, only slight or no improvement was noted in those diagnosed at older ages when screening was less extensive. In all time periods, a strong association was found between older age at diagnosis and poorer prognosis. CONCLUSION: Although alternative explanations for our findings must be seriously considered, the most obvious interpretation is that cytologic screening reduces mortality from cervical cancer by earlier diagnosis of invasive disease.

Adult↗

PubMed1994

Risk factors for fractures of the distal forearm: a population-based case-control study.

To evaluate the risk factors for early osteoporosis in consecutive patients with fracture of the distal forearm, a population-based case-control study was carried out using postal questionnaires supplemented by interviews when necessary. All men and women between the ages of 40 and 80 years who were resident in the County of Uppsala (population 265,000) and who sustained a fracture of the distal forearm during a defined 12-month period were initially included. Of 427 cases, 385 (90.2%) replied. Those with previous fragility fractures were excluded, leaving 367 patients in the study (mean age 61.9 +/- 10.6 years): 302 women (mean age 62.8 +/- 10.1 years) and 65 men (mean age 57.5 +/- 11.8 years). For each patient an age- and sex-matched control without previous fragility fractures was selected from the population register. The questionnaire concerned heredity, diseases and medications, general health, tobacco smoking and physical activity. Reproductive variables and postmenopausal hormone replacement therapy were analyzed extensively. In neither sex were any significant, consistent differences found with regard to chronic diseases, medications, physical activity or smoking. In females heredity for fractures (odds ratio, OR = 1.46) was associated with an increased risk. Nulliparous women had an increased risk of forearm fractures (OR = 1.72) while late menopause (OR = 0.95) and postmenopausal oestrogen therapy > 2 years (OR = 0.44) appeared to be protective. It is concluded that lifestyle factors did not discriminate between fracture patients and controls in this strict population-based investigation, suggesting that in affluent Western societies, with their high fracture rate, most individuals have an osteoporosis-prone way of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗