Biomedical subjects

Elisabete Weiderpass

Publications and source records attributed to Elisabete Weiderpass.

At least 55 records · Page 3Linked to original sources

PubMed2004

Mortality among workers employed in the titanium dioxide production industry in Europe.

OBJECTIVES: To assess the risk of lung cancer mortality related to occupational exposure to titanium dioxide (TiO2). METHODS: A mortality follow-up study of 15,017 workers (14,331 men) employed in 11 factories producing TiO2 in Europe. Exposure to TiO2 dust was reconstructed for each occupational title; exposure estimates were linked with the occupational history. Observed mortality was compared with national rates, and internal comparisons were based on multivariate Cox regression analysis. RESULTS: The cohort contributed 371,067 person-years of observation (3.3% were lost to follow-up and 0.7% emigrated). 2652 cohort members died during the follow-up, yielding standardized mortality ratios (SMRs) of 0.87 (95% confidence interval [CI] 0.83-0.90) among men and 0.58 (95% CI 0.40-0.82) among women. Among men, the SMR of lung cancer was significantly increased (1.23, 95% CI 1.10-1.38); however, mortality from lung cancer did not increase with duration of employment or estimated cumulative exposure to TiO2 dust. Data on smoking were available for over one third of cohort members. In three countries, the prevalence of smokers was higher among cohort members compared to the national populations. CONCLUSIONS: The results of the study do not suggest a carcinogenic effect of TiO2 dust on the human lung.

Adolescent↗

PubMed2004

TP53 mutations in squamous-cell carcinomas of the conjunctiva: evidence for UV-induced mutagenesis.

Squamous cell carcinoma of the conjunctiva is associated with sun exposure and often occurs in HIV-positive individuals. We have analysed TP53 mutations in 21 cases of squamous cell carcinoma and 22 controls with benign conjunctival lesions from a region (Uganda, Africa) with a high prevalence of heavy sun exposure and HIV infection. TP53 mutations were detected in 11 cases (52%) and 3 controls (14%). Seven of the mutations (6 in cases and 1 in controls) were CC-->TT transitions, a molecular signature of mutagenesis by solar UV rays. A similar prevalence (56%) of TP53 mutations was found in 18 squamous cell carcinoma cases positive for epidermodysplasia verruciformis human papillomavirus types. The prevalence of CC-->TT transitions reported here is the highest observed in any cancer type and matches that of skin cancers in subjects with xeroderma pigmentosum, an inherited disease with hypersensitivity to UV damage. These results confirm at the molecular level the causal role of solar UV rays in the aetiology of squamous cell carcinoma of the conjunctiva and suggest that infection with epidermodysplasia verruciformis types of human papillomavirus may act as a cofactor to increase the sensitivity of conjunctiva cells to UV-induced mutagenesis.

Adult↗

PubMed2004

A prospective study of body size in different periods of life and risk of premenopausal breast cancer.

The prevalence of obesity at all ages is increasing epidemically worldwide. Information on the association between premenopausal breast cancer and body size during childhood and teenage years is scarce. In 1991 to 1992, a prospective cohort study was assembled in Norway and Sweden. We included in the analysis presented here 99,717 premenopausal women. During the follow-up period, which ended in December 1999, 733 of these women developed a primary invasive breast cancer. Overweight and obesity [body mass index (BMI) > 25 kg/m(2)] at enrollment was associated with a decreased risk of premenopausal breast cancer (P for linear trend = 0.007). Apparent associations between perceived body shape at age 7 and BMI at age 18, with heavier builds at both ages seemingly being protective for premenopausal breast cancer risk, lost their statistical significance after adjustment for BMI at cohort enrollment. Body size at age 7 was correlated with BMI at age 18 (r = 0.43); BMI at age 18 was correlated with adult BMI (r = 0.48). Changes in body size from age 7 or 18 to adulthood did not affect per se risk of premenopausal breast cancer risk. Height was related to risk, with a statistically significantly 30% reduced risk only in women shorter than 160 cm as compared with taller ones. The decreased risk of premenopausal breast cancer was observed in overweight and obese women without, but not in those with, a family history of breast cancer.

Adult↗

PubMed2004

Cytochrome P450 1B1 gene polymorphisms and postmenopausal endometrial cancer risk.

Estrogen unopposed by progestins is a key factor in endometrial cancer etiology. Cytochrome P450 1B1 (CYP1B1), responsible for the 4-hydroxylation of estrogen, may be important in endometrial carcinogenesis, either as a regulator of estrogen availability or as a producer of potentially genotoxic estrogen metabolites. We investigated the association of CYP1B1 genotype and endometrial cancer risk in a population-based case-control study of postmenopausal Swedish women. We used the Expectation-Maximization algorithm to estimate the haplotype frequencies in the population and calculated odds ratios and 95% confidence intervals from conditional logistic regression models. In stratified analysis, we investigated the possible effects of CYP1B1 genotype on endometrial cancer risk in subgroups defined primarily by menopausal hormone use and also by body mass index, smoking, use of combined oral contraceptives, and family history. We genotyped 689 cases and 1,549 controls for the CYP1B1 single nucleotide polymorphisms m2, m3, and m4 and estimated the haplotype frequencies among controls to 0.086, 0.291, 0.452, and 0.169 for the CYP1B1*1, CYP1B1*2, CYP1B1*3, and CYP1B1*4 alleles, respectively. We found no evidence for an overall association between CYP1B1 genotype and endometrial cancer risk, nor was there any clear indication of gene-environment interaction.

Aged↗

PubMed2003

A prospective study of pigmentation, sun exposure, and risk of cutaneous malignant melanoma in women.

BACKGROUND: Although sun exposure is an established cause of cutaneous malignant melanoma, possible interactions with host factors remain incompletely understood. Here we report the first results from a large prospective cohort study of pigmentation factors and sun exposure in relation to melanoma risk. METHODS: The Women's Lifestyle and Health Cohort Study included 106 379 women from Norway and Sweden who were aged 30-50 years in 1991 or 1992 when they completed an extensive questionnaire on personal characteristics and exposures. Linkages to national registries ensured complete follow-up through December 31, 1999. Poisson regression models were used to estimate relative risks (RRs). All statistical tests were two-sided. RESULTS: During an average follow-up of 8.1 years, 187 cases of melanoma were diagnosed. Risk of melanoma was statistically significantly associated with increasing body surface area (RR for > or =1.79 m2 versus < or =1.61 m2 = 1.60, 95% confidence interval [CI] = 1.03 to 2.48; P(trend) =.02), number of large asymmetric nevi on the legs (RR for > or =7 nevi versus 0 nevi = 5.29, 95% CI = 2.33 to 12.01; P(trend)<.001), hair color (RR for red versus dark brown or black = 4.05, 95% CI = 2.11 to 7.76; P(trend)<.001), sunburns per year at ages 10-19, 20-29, and 30-39 years (P(trend)<.001, P(trend) =.03, and P(trend) =.05, respectively), and use of a device that emits artificial light (solarium) one or more times per month (P =.04). CONCLUSIONS: Our results confirm previous findings that hair color, number of nevi on the legs, and history of sunburn are risk factors for melanoma and suggest that use of a solarium is also associated with melanoma risk. Adolescence and early adulthood appear to be among the most sensitive age periods for the effects of sunburn and solarium use on melanoma risk. However, it may be too early to see the full effect of adult exposures in this cohort.

Adolescent↗

PubMed2003

Determinants of clearance of human papillomavirus infections in Colombian women with normal cytology: a population-based, 5-year follow-up study.

Little is known about the factors that influence clearance of human papillomavirus (HPV), the primary cause of cervical carcinoma. A total of 227 women cytologically normal and HPV positive at baseline were identified from a population-based cohort of 1,995 Bogota, Colombia, women aged 13-85 years followed between 1993 and 2000 (mean follow-up, 5.3 years). HPV DNA detection and viral load determination were based on a GP5+/GP6+ polymerase chain reaction enzyme immunoassay. Rate ratio estimates for HPV clearance were calculated by using methods for interval-censored survival time data. Analyses were based on 316 type-specific HPV infections. HPV 16 had a significantly lower clearance rate than infections with low-risk types (rate ratio (RR) = 0.47, 95% confidence interval (CI): 0.32, 0.72), HPV types related to HPV 16 (types 31, 33, 35, 52, 58) had intermediate clearance rates (RR = 0.62, 95% CI: 0.47, 0.94), and other high-risk types did not show evidence of slower clearance compared with low-risk types. Infections with single and multiple HPV types had similar clearance rates. There was no evidence of a dose-response relation between clearance and viral load. Observed was slower clearance in parous women (RR = 0.64, 95% CI: 0.47, 0.89) and faster clearance in ever users of oral contraceptives (RR = 1.38, 95% CI: 1.07, 1.77).

Adolescent↗

PubMed2003

Cytochrome P450 1B1 gene polymorphisms and postmenopausal breast cancer risk.

Cytochrome P450 1B1 (CYP1B1) is active in the metabolism of estrogens to reactive catechols and of different procarcinogens. Several studies have investigated the relationship between genetic polymorphisms of CYP1B1 and breast cancer risk, however, with inconsistent results. We investigated such an association in postmenopausal Swedish women, with special emphasis on long-term menopausal hormone users, in a large population-based case-control study. We genotyped 1521 cases and 1498 controls for the CYP1B1 single nucleotide polymorphisms (SNPs) m2, m3 and m4 and reconstructed haplotypes. The frequencies of CYP1B1*1, CYP1B1*2, CYP1B1*3 and CYP1B1*4 alleles among controls were estimated to be 0.087, 0.293, 0.444 and 0.175, respectively. It thus appeared that very few haplotypes contained combinations of SNPs at two or three loci and that single SNP genotype data effectively represented haplotypes. Odds ratios (OR) and 95% confidence intervals (CI) were calculated from logistic regression models. We found no overall association between any CYP1B1 genotype and breast cancer risk. The data indicated, however, that women who had used menopausal hormones for 4 years or longer, and carried the CYP1B1*3/*3 genotype may be at increased risk of breast cancer, OR 2.0 (95% CI 1.1-3.5), compared with long-term users without this genotype. We explored the effect of CYP1B1 genotype on breast cancer risk in subgroups defined by body mass index, family history, smoking and catechol-O-methyl transferase genotype, but found no convincing evidence for interaction. In summary, our results strongly indicate that the studied CYP1B1 gene polymorphisms do not influence breast cancer risk overall but may modify the risk after long-term menopausal hormone use.

Aged↗

PubMed2003

Catechol-O-methyltransferase gene polymorphism and post-menopausal breast cancer risk.

Estrogen is involved in breast carcinogenesis. Hypotheses have been raised that its effect is modified by enzymes such as catechol-O-methyltransferase (COMT) that deactivate potentially genotoxic estrogen metabolites. We have investigated the association between the functional genetic Val108/158Met polymorphism in COMT and breast cancer risk in a large population-based case-control study performed in the genetically homogeneous Swedish population. We determined COMT genotype in 1534 women with invasive breast cancer and in 1504 control women and calculated odds ratios (OR) and 95% confidence intervals (CI) from logistic regression models. There was no overall association between COMT genotype and breast cancer risk. However, the L allele was associated with an increased risk for lobular breast cancer, with OR 2.0 (95% CI 1.2-3.5) for HL and 1.7 (95% CI 0.9-3.0) for LL. In exploratory subset analyses, we found no statistically significant interaction, but some indication of a positive association between HL and LL genotypes and breast cancer among women with diabetes mellitus and a negative association among nulliparous women. Based on our findings, COMT activity alone does not seem to play a major role in breast carcinogenesis, but may be of importance in certain histotypes or in conjunction with other exposures.

Aged↗

PubMed2003

Occupational exposures and gastrointestinal cancers among Finnish women.

A cohort including all female workers born 1906 through 1945 (n = 413,877) in Finland was identified through the Population Census of Finland of 1970. Incident cases of cancers of the gastrointestinal tract were explored during 1971 to 1995. Job titles in census records were converted to exposures of 31 occupational agents through a job-exposure matrix. For each agent, the product of level and probability of exposures was calculated and subdivided in three categories: zero, low and medium/high. Poisson regression models estimated relative risks (RR) for each agent, standardized for birth cohort, follow-up period, and socioeconomic status. Adjustment at job title level was done for alcohol use for cancers of the esophagus and liver and smoking for pancreatic cancer. The results showing either statistically significant RR at the medium/high level of exposure (RRH) or statistically significant trend (P < 0.05) over the exposure categories were considered as positive findings. Colon cancer risk (2009 cases) was positively associated with sedentary work (RRH 1.3, 95% CI = 1.1-1.6; P trend 0.001) and negatively associated with perceived workload (P trend = 0.007). For stomach cancer (1881 cases), we observed an association with exposure to electromagnetic fields (RRH 1.44, 95% CI = 1.01-2.05) and man-made vitreous fibers (MMVF) (p trend 0.03). Rectal cancer (1323 cases) showed an association with chromium (RRH 1.9, 95% CI = 1.2-3.1) and oil mist (RR 2.0; 95% CI = 1.0-3.9). For pancreas cancer (1302 cases) we found associations with exposure to chromium (RRH 1.8; 95% CI = 1.0-3.1; P trend 0.01), electromagnetic fields (RRH 1.8; 95% CI = 1.2-2.8; P trend 0.02), and sedentary work (RRH 1.3; 95% CI = 1.0-1.7; P trend 0.05). We found no significant associations between any FINJEM agents and cancers of the esophagus (389 cases), liver (389 cases), and gallbladder (651 cases). Having examined the associations between seven cancer sites and over 30 exposures there exists the real possibility that some of the associations detected are chance findings. Therefore, the associations observed should need to be confirmed in other studies.

Colonic Neoplasms↗

PubMed2003

Organochlorines in Swedish women: determinants of serum concentrations.

We studied associations between lifestyle/medical factors and lipid-adjusted serum concentrations of seven polychlorinated biphenyl (PCB) congeners and five chlorinated pesticides/metabolites among 205 Swedish women (54-75 years old). Serum concentrations were significantly associated with age, body mass index, body weight change, diabetes mellitus, consumption of fatty fish, and place of residence. The findings suggest that lifestyle/medical factors may confound results in epidemiologic studies when they are related to both serum concentrations and disease. Moreover, disease itself may influence serum concentrations of some organochlorines, as indicated by the negative associations between recent weight change and serum concentrations of some PCB congeners, p,p -dichlorodiphenyldichloroethylene (DDE), and hexachlorobenzene (HCB) and the positive association between diabetes mellitus and HCB concentrations. Age was the only determinant that showed a consistent association with all compounds studied (positive); otherwise associations with single determinants varied among compounds even within the PCB group. This shows that the studied organochlorines should not be treated as a homogeneous group of compounds in epidemiologic studies.

Age Factors↗

PubMed2003

Cigarette smoking and the risk of gestational and pregestational diabetes in two consecutive pregnancies.

OBJECTIVE: Cigarette smoking during pregnancy may increase the risk of gestational diabetes mellitus (GDM) or pregestational diabetes mellitus (PDM). Smoking has been associated positively with hyperinsulinemia and insulin resistance in experimental studies, although the association with diabetes remains unclear. To further explore this issue, we examined the association with smoking in the largest prospective cohort study of GDM and PDM to date. RESEARCH DESIGN AND METHODS: The study population comprised 212190 women in the population-based Swedish Birth Registry who had their first and second deliveries between January 1987 and December 1995. Maternal characteristics were recorded in a standardized manner at the first prenatal visit, followed by a clinical examination and a standardized in-person interview to assess lifestyle habits. Women were categorized as nonsmokers, light smokers (one to nine cigarettes per day), or moderate-to-heavy smokers (at least 10 cigarettes per day). RESULTS: Women with GDM in their first pregnancy experienced an eight- to ninefold increased risk of GDM or PDM in their second pregnancy. Cigarette smoking was not associated with increased risk of these conditions. Neither women who smoked during their first and second pregnancies nor those who commenced smoking between pregnancies had a higher risk of GDM or PDM than nonsmokers. CONCLUSIONS: Our findings do not support an association between cigarette smoking and risk of GDM or PDM in young women of childbearing age.

Adult↗

PubMed2002

Socio-economic differences in incidence rates of cancers of the male genital organs in Finland, 1971-95.

We studied social class variation in the incidence of cancers of the prostate, testis, penis and scrotum among 1.1 million Finnish men (45-69 years of age) during 1971-95. The incidence of prostate cancer (6,972 cases) was increasing during the study period; the highest at all the times occurred in Social Class I (highest social class), 40-50% higher than in Social Class IV (lowest). The social class gradient was strongest in localized disease but there was some variation in incidence of non-localized prostate cancer. A total of 174 testicular cancer cases were diagnosed during the study period. In the early 1970s, the incidence of testicular cancer in Social Class I was 5-fold compared to Social Classes III and IV. Thereafter, the incidence rate decreased in Social Class I, but increased in the lower classes. The positive social class gradient was similar for seminomas and non-seminomas. For penile cancer (n = 128), the incidence decreased over time and social class variation was small. Only 6 cases of scrotum cancer were observed. In testicular cancer the strong positive social class association in the early 1970s is disappearing along with converging incidence trend slopes in different social classes. The difference diminished to less than 2-fold in the 1990s. Reasons for this observation remain open.

Finland↗

PubMed2002

Reduced risk of prostate cancer among patients with diabetes mellitus.

Although diabetes mellitus is associated with an increased risk of several malignancies, a negative association with prostate cancer is biologically most plausible. The epidemiologic evidence is, however, inconsistent, limited and based mostly on small studies. We present results from a large, population-based cohort study in Sweden, where we assessed prostate cancer risk among patients hospitalized for diabetes mellitus. The cohort was composed of patients identified in the Swedish In-Patient Register as having a hospital discharge diagnosis of diabetes mellitus in 1965-1994. The follow-up was done by linkages with the national cancer register and other population-based registers. Standardized incidence ratios (SIRs), with 95% confidence interval (CI), were used as a measure of relative risk. After complete exclusion of the first year of follow-up (to avoid selection bias), 135,950 men remained in the cohort, contributing 827,099 years of follow-up to the study. A total of 2,455 incident cases of primary prostate cancer were identified during 1-31 years of follow-up, yielding an overall SIR of 0.91 (95% CI 0.87-0.94); this risk reduction was more pronounced among patients who have been hospitalized for diabetic complications (SIR = 0.82; 95% CI 0.74-0.91). We found no consistent trends in risk related to age at first hospitalization or to duration of follow-up. We did find a small, but significantly decreased risk of prostate cancer among men who had been hospitalized for diabetes mellitus.

Adolescent↗

PubMed2002

Hormone replacement therapy and the risk of invasive epithelial ovarian cancer in Swedish women.

BACKGROUND: Estrogen replacement therapy (ERT), which is mainly used to relieve climacteric symptoms, increases a woman's risk for uterine endometrial cancer and epithelial ovarian cancer (EOC). Estrogens are often combined with progestins in hormone replacement therapy (HRT) to reduce the risk of uterine endometrial cancer. Data on the association between HRT including progestins and EOC risk are limited. This nationwide case-control study examined EOC risk in relation to HRT regimens with sequentially added progestins (HRTsp) and continuously added progestins (HRTcp). METHODS: Between 1993 and 1995, we enrolled 655 histologically verified incident case patients with EOC and 3899 randomly selected population controls, all 50-74 years of age. Data on HRT use were collected through mailed questionnaires. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by the use of unconditional logistic regression. RESULTS: Risks of EOC were elevated among ever users as compared with never users of both ERT (OR = 1.43, 95% CI = 1.02 to 2.00) and HRTsp (OR = 1.54, 95% CI = 1.15 to 2.05); risks were elevated for serous, mucinous, and endometrioid subtypes. For all EOC types combined, the greatest risk increases were seen with hormone use exceeding 10 years. Ever use of HRTcp was not associated with increased EOC risk relative to HRTcp never use (OR = 1.02, 95% CI = 0.73 to 1.43). The risk of EOC was elevated among HRTsp ever users as compared with HRTcp ever users (OR = 1.78, 95% CI = 1.05 to 3.01). ORs for EOC after ever use of low-potency estrogens were 1.18 (95% CI = 0.89 to 1.55) for oral and 1.33 (95% CI = 1.03 to 1.72) for vaginal applications, but no relationship was seen between EOC risk and duration of use. CONCLUSION: Ever users of ERT and HRTsp but not HRTcp may be at increased risk of EOC.

Adenocarcinoma, Clear Cell↗

PubMed2002

Cigarette smoking and the risk of endometrial cancer.

Epidemiological studies have shown that cigarette smoking is associated with a reduced risk of endometrial cancer, in contrast to the increased risks observed with many other non-respiratory-tract cancers, including those of the bladder, pancreas, and cervix uteri. Some studies of endometrial cancer suggest that the inverse association with smoking is limited to certain groups of women, such as those who are postmenopausal or those taking hormone-replacement therapy. The biological mechanisms that might underlie this association remain unclear, although several have been proposed, including an antioestrogenic effect of cigarette smoking on circulating oestrogen concentrations, a reduction in relative bodyweight, and an earlier age at menopause. We have examined the evidence for an association between cigarette smoking and risk of endometrial cancer, including studies related to the proposed biological mechanisms.

Adenocarcinoma↗

PubMed2002

Diabetes mellitus and ovarian cancer (Sweden).

OBJECTIVE: We present results from a large, population-based cohort study in Sweden, where we assessed ovarian cancer risk among patients hospitalized for diabetes mellitus. METHODS: The cohort was composed of patients identified in the Swedish In-Patient Register as having a hospital discharge diagnosis of diabetes mellitus in 1965-1994. The follow-up was done by linkages with the national cancer register and other population-based registers. Standardized incidence ratios (SIR) were used as a measure of relative risk. RESULTS: After exclusion of the first year of follow-up (to avoid selection bias), 141,627 women remained in the cohort, contributing 865,746 years of follow-up to the study. The overall SIR for ovarian cancer was 0.97 (95% confidence interval (CI) 0.87-1.08). We found no difference in the risk estimates among women who had been hospitalized for classic complications of diabetes and for those who had not, or according to the duration of follow-up. Women above 40 years of age at first hospitalization presented a SIR of 0.96 (95% CI 0.85-1.07). CONCLUSIONS: Our study provides evidence of lack of an association between diabetes mellitus and ovarian cancer.

Adult↗

PubMed2002

Central nervous system tumours in children in Costa Rica, 1981-96.

Incidence rates of malignant central nervous system (CNS) tumours in children in Costa Rica are presented in an international perspective. For the 16-year period 1981-96, a total of 256 CNS tumours were registered in children below age 15 years by the National Tumour Registry of Costa Rica. The age-standardised incidence rate was 15.2 per million person-years, with a male-to-female ratio of 1.4. The median age-standardised incidence rates of selected registries in other Latin American countries were 19.3, in other developing countries 12.0 and in industrialised countries 29.6 per million person-years. The comparatively low incidence rates in Costa Rica were evident in all diagnostic subgroups, most notably in the youngest age group and for tumours in the brain stem. In the Central Valley, where the capital and the only specialised paediatric hospital are situated, the crude incidence rate was 18.1 [95% CI 15.1, 21.1] compared with 10.5 [95% CI 8.3, 12.8] per million person-years in the rest of the country (RR = 1.7, 95% CI 1.3, 2.3). There was no evidence of any increase over time. The data in this study cannot exclude under-diagnosis and, to a lesser degree, under-registration as a partial explanation of the low incidence rates of malignant CNS tumours in children in Costa Rica.

Adolescent↗

PubMed2002

Childhood leukaemia in Costa Rica, 1981-96.

Childhood leukaemia incidence in Costa Rica during 1981-96, among the highest in the world, was analysed by histology, gender, birth year, time period of diagnosis, age at diagnosis and region. Numbers of cases were extracted from the database of the National Cancer Registry (RNT) of Costa Rica. Person-years at risk were calculated from census data and post-census population estimates. During the follow-up, 918 cases of leukaemia in children under 15 years (510 boys, 408 girls) were reported to the RNT (41% of all childhood malignancies), with an overall age-standardised incidence rate of 56 per million person-years. Acute lymphocytic leukaemia (ALL) represented 79% and acute non-lymphocytic leukaemia (ANLL) 16% of the cases, with rates of 43 and 9 per million person-years respectively. There were downward trends in incidence of total leukaemias, ALL and ANLL and 'not otherwise specified' (NOS) combined. Incidence of ALL was highest at 1-4 years of age in boys and girls, whereas ANLL peaked in girls during the first year of life. During 1991-96, the decrease in ALL was significant (P = 0.042). A multivariable Poisson regression model identified significant excesses of ALL for boys, for age groups 1-4 and 5-9 years and for three out of seven regions. Possible reasons for the high rates in Costa Rica are discussed.

Adolescent↗