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Biomedical subjects

V Beral

Publications and source records attributed to V Beral.

At least 91 records · Page 5Linked to original sources
PubMed1993

Case-control study of prostatic cancer in employees of the United Kingdom Atomic Energy Authority.

OBJECTIVE: To investigate the relation between risk of prostatic cancer and occupational exposures, especially to radionuclides, in employees of the United Kingdom Atomic Energy Authority. DESIGN: Case-control study of men with prostatic cancer and matched controls. Information about sociodemographic factors and exposures to radionuclides and other substances was abstracted and classified for each subject from United Kingdom Atomic Energy Authority records without knowledge of who had cancer. SUBJECTS: 136 men with prostatic cancer diagnosed between 1946 and 1986 and 404 matched controls, all employees of United Kingdom Atomic Energy Authority. MAIN OUTCOME MEASURES: Documented or possible contamination with specific radionuclides. RESULTS: Risk of prostatic cancer was significantly increased in men who were internally contaminated with or who worked in environments potentially contaminated by tritium, chromium-51, iron-59, cobalt-60, or zinc-65. Internal contamination with at least one of the five radionuclides was detected in 14 men with prostatic cancer (10%) and 12 controls (3%) (relative risk 5.32 (95% confidence interval 1.87 to 17.24). Altogether 28 men with prostatic cancer (21%) and 46 controls (11%) worked in environments potentially contaminated by at least one of the five radionuclides (relative risk 2.36 (1.26 to 4.43)); about two thirds worked at heavy water reactors (19 men with prostatic cancer and 32 controls (relative risk 2.13 (1.00 to 4.52)). Relative risk of prostatic cancer increased with increasing duration of work in places potentially contaminated by these radionuclides and with increasing level of probable contamination. Prostatic cancer was not associated with exposure to plutonium, uranium, cadmium, boron, beryllium, or organic or inorganic chemicals. CONCLUSIONS: Risk of prostatic cancer risk was increased in United Kingdom Atomic Energy Authority workers who were occupationally exposed to tritium, 51Cr, 59Fe, 60Co, or 65Zn. Exposure to these radionuclides was infrequent, and their separate effects could not be evaluated.

Adult↗
PubMed1993

Antibodies to human papillomavirus and to other genital infectious agents and invasive cervical cancer risk.

Human papillomaviruses (HPVs) play an important part in the development of cervical cancer, but the role of other infectious agents, such as herpes simplex virus (HSV), is not clear. We assayed serum samples collected from 219 women with cervical cancer and from 387 controls for antibody to infectious agents. HPV 16-E7 and/or HPV 18-E7 antibodies were significantly related to cervical cancer risk (RR 1.9, 95% CI 1.2-3.2). Antibodies to HSV types 1 and 2, Chlamydia trachomatis, and to multiple infectious agents were associated with cervical cancer when seroprevalence rates in all cases and controls were compared, but when HPV-seropositive cases and controls were compared these associations were weaker and non-significant. This finding suggests that past infections with sexually transmitted infections other than HPV may be surrogate markers of exposure to HPV, and of no separate aetiological significance.

Adult↗
PubMed1993

Case-control study of leukaemia and non-Hodgkin's lymphoma among children aged 0-4 years living in west Berkshire and north Hampshire health districts.

OBJECTIVE: To investigate the relation between parental employment in the nuclear industry and childhood leukaemia and non-Hodgkin's lymphoma. DESIGN: Case-control study. SETTING-West Berkshire and Basingstoke and North Hampshire District Health Authorities. SUBJECTS: 54 children aged 0-4 years who had leukaemia or non-Hodgkin's lymphoma diagnosed during 1972-89, who were born in the study area and were resident there when cancer was diagnosed. Six controls were selected for each case: four from hospital delivery registers and two from livebirth registers maintained by the NHS central register. Controls were matched for sex, date of birth (within six months), and area of residence at birth and time of diagnosis. MAIN OUTCOME MEASURES: Parents' employment by the nuclear industry and exposure to ionising radiation at work. RESULTS: Five (9%) of the 54 cases and 14 (4%) of the 324 controls had fathers or mothers, or both, who had been employed by the nuclear industry (relative risk 2.2, 95% confidence interval 0.6 to 6.9). Nuclear industry employees who work in areas where exposure to radiation is possible are given film badges to monitor their exposure to external penetrating ionising radiation. Three fathers of cases and two fathers of controls (and no mothers of either) had been monitored in this way before their child was conceived (relative risk 9.0, 95% confidence interval 1.0 to 107.8). No father (of a case or control) had accumulated a recorded dose of more than 5 mSv before his child was conceived, and no father had been monitored at any time in the four years before his child was conceived. A dose-response relation was not evident among fathers who had been monitored. CONCLUSIONS: These results suggest that the children of fathers who had been monitored for exposure to external penetrating ionising radiation in the nuclear industry may be at increased risk of developing leukaemia before their fifth birthday. The finding is based on small numbers and could be due to chance. If the relationship is real the mechanisms are far from clear, except that the effect is unlikely to be due to external radiation; the possibility that it could be due to internal contamination by radioactive substances or some other exposure at work should be pursued. The above average rates of leukaemia in the study area cannot be accounted for by these findings.

Case-Control Studies↗
PubMed1993

Age-specific differences in the relationship between oral contraceptive use and breast cancer.

BACKGROUND: Nearly all studies have suggested that the use of oral contraceptives (OC) is not associated with the aggregate risk of breast cancer diagnosed in women aged 20-54 years. Because of age-specific differences in the breast cancer-parity relationship and because of age-specific differences in other breast cancer risk factors, the Centers for Disease Control reexamined data from the Cancer and Steroid Hormone Study (CASH) to assess whether OC use has different effects on the risk of breast cancer at different ages of diagnosis. METHODS: This population-based case-control study was designed to examine the relationship between the use of OC and the risk of breast, ovarian, and endometrial cancer. CASH was conducted in eight geographic areas in the United States during 1980-1982. All participants were interviewed at home with a pretested standardized questionnaire including a calendar of life events and a photograph book of all pills marketed in the United States. RESULTS: We found that the relationship between the risk of breast cancer and OC use appeared to vary by the age at diagnosis. Among women aged 20-34 years at diagnosis or interview, those who had ever used OC had a slightly increased risk of breast cancer (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.0-2.1) compared with women of the same ages who had never used OC. Among these women, there were no trends of increasing or decreasing risk with any measure of OC use. Among women aged 35-44 years, there was no association between OC use and breast cancer. Among women aged 45-54 years, those who used OC had a slightly decreased risk of breast cancer (OR, 0.9; 95% CI, 0.8-1.0). Among these women, risk estimates decreased significantly with increasing time since first and last use. CONCLUSIONS: Although the slightly increased risk estimates for the youngest women were compatible with findings by other investigators, the decreased risk estimates for the oldest women have not been described in as many studies. Available data provide no reasons to change prescribing practices or the use of OC that are related to the breast cancer risk.

Adult↗
PubMed1993

Fertility and use of cigarettes, alcohol, marijuana, and cocaine.

This study demonstrated that cigarette smoking was associated with an increase in both time to conception (among 2817 fertile women) and risk of primary infertility (among 1818 infertile women and their primiparous control subjects). The average time to conception was 4.3 months for women who never smoked, 4.6 months for those who smoked in the past, and 5.1 months for those who currently smoked. The delay in conception for current smokers remained significant after adjusting for confounders (risk ratio of 0.9 (0.8 to 1.0)). Additionally, current smokers were at increased risk of primary infertility (odd ratios of 1.9 (1.5 to 2.3)). For alcohol use, the average time to conception and risk of primary infertility did not vary by level of consumption. The average time to conception was significantly shorter for women who had used marijuana regularly and for women who had ever used cocaine than for women who had never used these drugs. Because of the increased use of marijuana and cocaine among young adults, further investigations of these associations are needed.

Canada↗
PubMed1993

Cancer mortality and morbidity in employees of the United Kingdom Atomic Energy Authority, 1946-86.

In further analyses of a cohort of 39,718 United Kingdom Atomic Energy Authority employees after 7 more years follow-up, cancer mortality, based on 1,506 deaths in 1946-86, was 20% below the national average. Prostatic cancer mortality showed a statistically significant association with external radiation exposure, largely confined to men who were also monitored for internal contamination by radionuclides other than plutonium. Prostatic cancer mortality was highest in radiation workers at Winfrith. In women monitored for radiation exposure, mortality from cancer of the uterus (including the cervix uteri) was increased relative to other employees, and, showed a statistically significant association with external radiation exposure. While there were some other statistically significant results, as would be expected by chance alone when multiple comparisons are made, there were no other cancer sites with consistently exceptional findings. Point estimates for risk associated with increasing exposure to radiation suggest a decrease of four deaths per 10(4) person-years per Sv for leukaemia and an increase of 20 deaths for all cancers except leukaemia, but confidence intervals indicate that a wide range of values are compatible with the data. Cancer morbidity based on 1,699 registrations in 1971-84 was 12% below the national average. Findings from site-specific analyses largely replicated those of the mortality analyses.

Cause of Death↗
PubMed1992

Thyroid nodules in the population living around Chernobyl.

OBJECTIVE: To determine the baseline incidence, prevalence, and characteristics of thyroid nodules in the population living around the Chernobyl nuclear power plant and to compare the findings with unexposed populations. DESIGN: Prevalence study. Population samples from seven highly contaminated villages were compared with six nearby control villages of the same size and type. The data were obtained as part of the International Chernobyl Project conducted in 1990. SETTING: The study was conducted 4.5 years after the Chernobyl reactor accident that released large quantities of radionuclides, including radioiodine. PATIENTS OR OTHER PARTICIPANTS: Population samples of approximately 100 persons residing in both highly contaminated villages and control villages since the accident were compared. Individuals were selected on the basis of birth date as being 5, 10, 40, or 60 years old at the time of the study. All persons selected underwent a thyroid examination. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Two main outcome measures were used, both for thyroid nodularity: clinical palpation and high-resolution ultrasonography. RESULTS: There was no significant difference in thyroid nodularity between the study groups. Nodules were palpated in 0.7% of children and 2.9% of adults. Discrete nodules were found by ultrasonography in 0.5% of children and 14.9% of adults. Multinodular goiter was found in 3% of adults. Nodules were more common in females. CONCLUSIONS: Four and a half years after the Chernobyl accident, the incidence, prevalence, and characteristics of thyroid nodules were the same in population samples from both highly contaminated and control settlements and similar to results reported for unexposed populations in other countries.

Accidents↗
PubMed1992

Risk of Kaposi's sarcoma and sexual practices associated with faecal contact in homosexual or bisexual men with AIDS.

The causal agent of Kaposi's sarcoma is unknown. That the disorder is ten times more common in homosexual or bisexual men with the acquired immunodeficiency syndrome (AIDS) than in other human immunodeficiency virus (HIV) transmission groups suggests that a certain aspect of their behaviour exposes them to the agent or facilitates its spread. We therefore assessed social and demographic characteristics, including sexual behaviour, of 65 homosexual or bisexual men with AIDS from London. Sexual practices in which there was contact with partner's faeces before AIDS developed were the main determinants of Kaposi's sarcoma risk. Risk increased with frequency of insertive "rimming" (oral-anal contact): Kaposi's sarcoma developed in 18% of the men with AIDS who reported never having practised insertive rimming compared with 50% who practised it less than once a month, 73% between once a week and once a month, and 75% or more once a week (two-sided exact p-value for trend less than 0.001). 45 men had been interviewed about their sexual practices before AIDS developed, and 20 were interviewed at the time the syndrome developed. The findings were similar and statistically significant when each group was analysed separately. The men with Kaposi's sarcoma also tended to be more sexually active and were more likely to engage in other sexual activities that entailed contact with faeces than were the men who had other features of AIDS only. Other behaviours and exposures, including the use of "poppers" (nitrite inhalants), were not related to Kaposi's sarcoma risk, after taking into account whether the subjects had practised insertive rimming. The data suggest that faecal-oral contact is the main route of transmission of the agent of Kaposi's sarcoma in homosexual or bisexual men with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Obstetric outcome of in vitro fertilization pregnancies compared with normally conceived pregnancies.

OBJECTIVE: To compare the obstetric outcome of in vitro fertilization pregnancies with normally conceived pregnancies. STUDY DESIGN: The obstetric outcome of in vitro fertilization pregnancies achieved in 763 British residents at two in vitro fertilization clinics resulting in the births of 961 babies were compared by means of the relative risk statistic with a control group of naturally conceived primiparous pregnancies matched by maternal age and multiplicity of pregnancy. RESULTS: Twenty-five percent of in vitro fertilization pregnancies were multiple pregnancies. The incidence of singleton term breech presentation was similar to that among controls. As compared with controls there was an increased incidence among in vitro fertilization pregnancies of vaginal bleeding and hypertension requiring hospitalization (p less than 0.001) and cesarean births (p less than 0.001) and, among in vitro fertilization singleton pregnancies, an increased incidence of intrauterine growth retardation (p less than 0.05), placenta previa (p less than 0.05), and preterm delivery (p less than 0.001). The congenital malformation, stillbirth, and perinatal mortality rates were comparable with maternal age-standardized national rates. CONCLUSIONS: Although the majority of in vitro fertilization pregnancies have a satisfactory obstetric outcome, there are a number of increased obstetric risks that may reflect the history of infertility, the relatively high incidence of poor obstetric history, and the lower threshold for obstetric intervention in in vitro fertilization patients.

Adult↗
PubMed1992

Kaposi's sarcoma in England and Wales before the AIDS epidemic.

The epidemiological features of Kaposi's Sarcoma (KS) incidence in England and Wales in the period 1971-1980 are reviewed. The epidemiology of KS in England and Wales in this period is distinct from that associated with the AIDS epidemic. The incidence was probably very low compared to other Western countries, there was little male excess, and no indication, based on marital status data, of a raised incidence in male homosexuals. Half the cases registered were in people born outside the UK. The region of birth distribution in these migrants reflected the known pre-AIDS geographic distribution of KS and also pointed to high risks in those from Middle Eastern countries and the Caribbean. The very low incidence rates of KS in natives of England and Wales suggests that the background prevalence of the causative agent for KS was low in England and Wales prior to the AIDS epidemic.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Preterm delivery, low birthweight and small-for-gestational-age in liveborn singleton babies resulting from in-vitro fertilization.

The Medical Research Council In-Vitro Fertilization (IVF) Register report on births resulting from assisted conception in Great Britain demonstrated a high incidence of preterm and low birthweight babies. This incidence remained high even when the analysis was restricted to singleton babies. The present paper investigates possible risk factors for prematurity, low birthweight and small-for-gestational-age (SGA) in singleton IVF births. Thirteen per cent of singleton IVF babies were preterm, 11% low birthweight and 17% small-for-gestational-age. Analysis by multiple regression indicated that hypertension during pregnancy was an independent risk for preterm delivery, low birthweight and SGA, bleeding during pregnancy for preterm delivery, and the number of embryos transferred and the type of infertility for low birthweight.

Female↗
PubMed1992

A case-control study of benign ovarian tumours.

STUDY OBJECTIVE: The aim was to investigate the association between reproductive, contraceptive, and menstrual factors and risk of benign ovarian tumours. DESIGN AND SETTING: This was a case-control study carried out in six London Hospitals. An interviewer administered questionnaire was used. SUBJECTS: 62 women with a benign epithelial ovarian neoplasm, 37 women with a functional ovarian cyst, and 20 women with a dermoid cyst presenting between 1983 and 1985, together with 132 controls, took part in the study. MAIN RESULTS: On average, women with a benign epithelial ovarian neoplasm were older than those with a functional ovarian cyst, who in turn were older than those with a dermoid cyst. Nulliparity and infertility were associated with an increased risk, and multiparity with a reduced risk, of benign epithelial ovarian neoplasms. Infertility and pelvic inflammatory disease were associated with increased risks of functional and dermoid cysts. Recent use of oral contraceptives was associated with a reduced risk of all three tumour types. CONCLUSIONS: The findings suggest that the aetiology of ovarian cysts and benign epithelial ovarian neoplasms may differ. The aetiology of benign and malignant epithelial ovarian neoplasms may be similar, however, since some risk factors are shared.

Adolescent↗