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S Preston-Martin

Publications and source records attributed to S Preston-Martin.

At least 19 recordsLinked to original sources
PubMed2002

Contacts with animals and humans as risk factors for adult brain tumours. An international case-control study.

While numerous studies have addressed the possible role of farming and related exposures as risk factors for brain tumours in adults, few of them have examined the potential effect of exposure to farm animals or pets. In an international multicentre case-control study, we investigated whether residence on a farm, contact with animals, or working in occupations with a high degree of potential contact with animals or humans were associated with brain tumours. Using a common questionnaire, 1177 cases of glioma, 330 with meningioma and 2478 controls from eight centres were interviewed about the exposures and, in particular, about their contacts with nine species of animals: dairy cattle, beef cattle, pigs, horses, sheep, goats, poultry, dogs and cats. Living or working on a farm was not a risk factor, for either glioma or meningioma. Except in some centres, there was no relationship between having contacts with farm animals or pets and the risk of brain tumour, for either type of tumour or either sex. In relation to seven industrial groups involving frequent human and/or animal contacts, no association was apparent for either glioma or meningioma. In relation to 25 occupational groups with potential frequent contact with humans and/or animals, for glioma there was a reduced risk for biological technicians (Odds Ratio (OR)/=0, P=0.01), and general farm workers (OR=0.66, 95% Confidence Interval (CI): 0.5-0.9). For meningioma, there was an increased risk for cooks (OR=2.0; CI: 1.2-3.4). With some exceptions, these results indicate no association between either the type of brain tumour and contacts with animals, or with occupations that include a high level of contact with animals or a high level of contact with humans.

Adult↗
PubMed2001

A pooled analysis of case-control studies of thyroid cancer. VI. Fish and shellfish consumption.

OBJECTIVE: To better understand the role of fish and shellfish on thyroid cancer risk, we systematically re-analyzed the original data from 13 case-control studies conducted in the US, Japan, China, and Europe. METHODS: A total of 2497 cases (2023 women, 474 men) and 4337 controls (3268 women, 1069 men) were considered. Odds ratio (OR) and corresponding 95% confidence interval (CI) were estimated for each study by logistic regression models, conditioned on age and sex, and adjusted for history of goiter, thyroid nodules or adenomas, and radiation. Combined ORs were computed as the weighted average of the estimates from each study. RESULTS: The ORs for the highest level of total fish consumption (three or more times per week) as compared to the lowest one (less than once per week) was above unity in Hawaii, Connecticut, Japan, Norway, Tromsø, and Vaud. Conversely, the ORs for the studies in Los Angeles. Shanghai, southeastern Sweden, Uppsala, northern Sweden, northern Italy, and Athens were below one. The pattern of risk for salt water fish and shellfish was not substantially different from that of total fish. Fish was not associated with thyroid cancer risk in all studies combined (OR = 0.99, 95% CI 0.85-1.2 for moderate, and OR=0.88, 95% CI 0.71-1.1 for high total fish consumption), but there was a suggestion of a protective effect in endemic goiter areas (OR = 0.65, 95% CI 0.48-0.88). CONCLUSION: This combined analysis indicates that relatively elevated fish consumption does not appreciably increase thyroid cancer risk, and may have a favorable influence in areas where iodine deficiency is, or was, common.

Adult↗
PubMed2001

Parental occupations and childhood brain tumors: results of an international case-control study.

OBJECTIVE: To evaluate the role of parental occupations in the etiology of childhood brain tumors (CBT). METHODS: Population-based case-control studies were conducted concurrently in seven countries under the coordination of the International Agency for Research on Cancer, gathering 1,218 cases and 2,223 controls. We report here the findings related to parental occupations during the 5-year period before the child's birth. Risk estimates related to a number of paternal and maternal occupations were obtained by unconditional logistic regression adjusted for age, sex, year of birth, and center, for all types of CBT combined and for the subgroups of astroglial, primitive neuroectodermal tumors (PNET), and other glial tumors. RESULTS: An increased risk in relation with agricultural work was seen for all CBT combined and for other glial tumors. Increased risks for all tumors and PNET were seen for paternal occupation as an electrician; the same pattern held for maternal occupation when children under 5 were selected. Paternal occupation as a driver or mechanic, and maternal work in an environment related to motor-vehicles were associated with an increased risk for all CBT and astroglial tumors. More case mothers compared to control mothers were employed in the textile industry. CONCLUSION: Our study reinforces previous findings relative to the role of parental work in agriculture, electricity, or motor-vehicle related occupations and maternal work in the textile industry. It does not confirm previous associations with work environments including aerospace, the chemical industry, or the food industry, or with maternal occupation as a hairdresser, a nurse, or a sewing machinist, and paternal occupation as a welder.

Adolescent↗
PubMed2001

Maternal cured meat consumption during pregnancy and risk of paediatric brain tumour in offspring: potentially harmful levels of intake.

OBJECTIVE: To describe the relationship between specific levels of nitrite intake from cured meat consumption during pregnancy and the relative risk of paediatric brain tumours in the offspring. DESIGN: Exposure data were previously collected for a population-based case-control study of paediatric brain tumours; data on nitrite content were obtained by a comprehensive literature review of surveys of residual nitrite content in cured meats published in the USA and Canada. The level of nitrite intake for each mother was predicted by year of pregnancy based on survey results. Dose-response was evaluated both categorically and continuously using polynomial and quadratic spline regression. SETTING: The US west coast: Los Angeles County, the San Francisco-Oakland Bay Area and the Seattle-Puget Sound area. SUBJECTS: There were 540 cases diagnosed between 1984 and 1990 at ages varying from 0 to 19 years, and 801 controls frequency-matched by geographic area, age and birth year. RESULTS: In general, survey results suggest a trend of decreasing nitrite levels in cured meats over time. We observed a moderate increase in brain tumour risk in the offspring of mothers with relatively low levels of nitrite consumption from cured meats during pregnancy, and a two- to three-fold risk increase in offspring of mothers who consumed 3 mg day-1 nitrite from cured meats (about 125 g day-1 of cured meat consumption throughout the pregnancy). CONCLUSIONS: A substantial risk of paediatric brain tumour appears to be associated with relatively high levels of maternal cured meat consumption during pregnancy. A more scientifically valid approach than a literature review to estimate nitrite intake from cured meats and data from a large group of highly exposed subjects would be useful in determining potentially harmful levels.

Animals↗
PubMed2001

Residential water source and the risk of childhood brain tumors.

Gestation may represent a window of susceptibility to transplacental effects of environmental exposures, including chemicals in water. The N-nitroso compounds (NNC), a class of chemicals with demonstrated neurocarcinogenic potential, include substances detected in drinking water. We used data from a study of possible risk factors for childhood brain tumors (CBT) to investigate the association of source of residential drinking water during pregnancy and CBT occurrence among offspring. In addition, dipstick measurements were made of nitrates and nitrites in tap water for the subset of women living in the same home they had lived in during their pregnancies. Population-based CBT cases (n = 540) and controls (n = 801) were identified in three regions including Los Angeles County, and the San Francisco Bay Area of California, and the Seattle-Puget Sound area of western Washington state. Overall, we observed no increased risk of CBT in offspring associated with wells as the source of residential water. However, an increased risk of CBT [odds ratio (OR) = 2.6; 95% confidence interval (CI), = 1.3-5.2] was observed in western Washington among offspring of women who relied exclusively on well water, and a decreased risk of CBT (OR = 0.2; 95% CI, 0.1-0.8) was observed in Los Angeles County. Among the small subset of subjects for whom dipstick measurements of tap water were available, the risk of CBT associated with the presence of either measurable nitrite and/or nitrate was 1.1 (95% CI, 0.7-2.0). Given the crude measurement method employed and because measurements often were obtained years after these pregnancies occurred, the relevance of the dipstick findings is unclear. The lack of consistency in our findings related to residential water source does not support the hypothesis of increased risk related to consumption of well water; however, regional differences in well water content may exist, and the increased risk observed in western Washington deserves further evaluation.

Adolescent↗
PubMed2000

Descriptive epidemiology of thyroid cancer in Los Angeles County, 1972-1995.

OBJECTIVE: To examine the descriptive epidemiologic features of incident thyroid cancers diagnosed among Los Angeles County residents between 1972 and 1995. METHODS: The Los Angeles County/University of Southern California Cancer Surveillance Program (CSP) collected data on 8820 newly diagnosed thyroid cancer of cases occurring in Los Angeles County. Average annual age-adjusted incidence rates were calculated to study the epidemiology of each of the major histologic types of thyroid carcinoma. RESULTS: For all races combined, the age-adjusted incidence rates were 2.5 per 100,000 males and 6.0 per 100,000 females. Differences in incidence by ethnicity were particularly striking, with Filipinos demonstrating the highest incidence rates (4.44 per 100,000 males, 11.3 per 100,000 females). Over the 23-year period, thyroid cancer incidence rates increased 1.5% per year for males and 1% per year for females. By histology, papillary carcinoma rates increased over time and follicular carcinoma rates decreased. Non-Spanish surnamed white men employed in certain white-collar occupations and radiologic technicians were at greater risk of thyroid cancer. CONCLUSIONS: Additional research on the epidemiologic risk factors for thyroid cancer, particularly for gender and ethnicity, is needed to explain the marked elevated incidence rates among females and the Filipino population in Los Angeles County.

Adolescent↗
PubMed2000

A pooled analysis of thyroid cancer studies. V. Anthropometric factors.

OBJECTIVE: To assess the relation between anthropometric factors and thyroid cancer risk in a pooled analysis of individual data from 12 case-control studies conducted in the US, Japan, China and Europe. METHODS: 2056 female and 417 male cases, 3358 female and 965 male controls were considered. Odds ratios (OR) were derived from logistic regression, conditioning on age, A-bomb exposure (Japan) and study, and adjusting for radiotherapy. RESULTS: Compared to the lowest tertile of height, the pooled OR was 1.2 for females for the highest one, and 1.5 for males, and trends in risk were significant. With reference to weight at diagnosis, the OR for females was 1.2 for the highest tertile, and the trend in risk was significant, whereas no association was observed in males. Body mass index (BMI) at diagnosis was directly related to thyroid cancer risk in females (OR = 1.2 for the highest tertile), but not in males. No consistent pattern of risk emerged with BMI during the late teens. Most of the associations were observed both for papillary and follicular cancers, and in all age groups. However, significant heterogeneity was observed across studies. CONCLUSIONS: Height and weight at diagnosis are moderately related to thyroid cancer risk.

Adult↗
PubMed2000

Reliability of demographic, smoking and occupational data provided by mothers vs. fathers in a childhood cancer study.

A large case-control study of children was used to test mothers' reporting of information on fathers' background, lifestyle and occupational factors. For a subset (104) of 1341 enrolled families, both parents were interviewed about fathers' characteristics. Reliability of reporting was determined for fathers' race, education, smoking status, non-recent job history and use of occupational agents. The ability of mothers to report fathers' race, education and smoking status was high (kappa > 0.70). Mothers were generally able to report jobs held by the fathers in the 5 years preceding the birth of the child, but reliability was higher for jobs held for longer (kappa typically above 0.70), rather than shorter periods (kappa above 0.40). The finding that mothers' reporting on fathers' background, lifestyle and non-recent job history was reliable is encouraging, because many studies on childhood health rely exclusively on information from interviews with mothers. However, mothers were not reliably able to describe exposure to specific occupational agents.

California↗
PubMed1999

Role of medical history in brain tumour development. Results from the international adult brain tumour study.

In an international population-based case-control study carried out in 8 centres in 6 countries, we investigated the role of specific medical conditions in the aetiology of brain tumours in adults. Recruited were 1,178 glioma and 331 meningioma cases and 2,493 age- and gender-matched population controls. Only medical conditions occurring at least 2 years before brain tumour diagnosis were considered. Relative risks (RRs) and 95% confidence intervals (CIs) were estimated using a conditional logistic regression model. Heterogeneity between centres was tested. No association between meningioma and previous medical conditions was observed. For glioma, there was an increased risk associated with epilepsy (RR = 6.55, 95% CI 3.40-12.63), but this was considerably weaker for epilepsy of more than 20 years duration. The risk remained elevated after adjustment for use of anti-epileptic drugs. There was a statistically significant inverse association between glioma and all allergic diseases combined (RR = 0.59, 95% CI 0.49-0.71); this was also observed for specific allergic conditions, namely, asthma and eczema. Subjects who reported a history of infectious diseases (e.g., colds, flu) showed a 30% reduction in risk (RR = 0.72, 95% CI 0.61-0.85). The decreased risks for glioma in subjects reporting a history of allergic conditions or infectious diseases may indicate an influence of immunological factors on the development of glioma. The association between glioma and epilepsy has to be interpreted cautiously and needs further investigation.

Adult↗
PubMed1999

Childhood brain tumors and residential electromagnetic fields (EMF).

There are many recent comprehensive reviews of the residential EMF epidemiologic literature, but they do not attempt to cover the issue of childhood brain tumors and EMF in depth. We present here background information on descriptive epidemiology of known or suspected causes of childhood brain tumors and a detailed review of studies that have examined the associations between EMF as represented by various surrogates, and childhood brain tumors. We evaluated nine studies of childhood brain tumors and residential exposure to EMF based on wire codes, distance, measurements, and modeling, and six studies that examined the use of appliances by children or their mothers during pregnancy. For each study we discussed analytical and methodological issues including choice of cutpoints, nonconcurrent control selection, random digit dialing, differential participation, and ability of a study to detect an association. On the basis of this comprehensive review of all available childhood brain cancer studies, we do not see support for an overall association between EMF and childhood brain cancer. This lack of support applied for all surrogates of past magnetic fields, including wire code, distance, measured or calculated fields, and use of appliances by either child or mother.

Brain Neoplasms↗
PubMed1999

A pooled analysis of case-control studies of thyroid cancer. III. Oral contraceptives, menopausal replacement therapy and other female hormones.

OBJECTIVE: The relations between oral contraceptives (OC), hormone replacement therapy (HRT) for menopause, and other female hormone use and thyroid cancer risk was analyzed using the original data from 13 studies from North America, Asia and Europe. METHODS: Based on 2,132 cases and 3,301 controls, odds ratios (OR) and the corresponding 95% confidence intervals (CI) were obtained by conditional regression models, conditioning on study and age at diagnosis, and adjusting for age, radiation exposure and parity. RESULTS: Overall, 808 (38%) cases versus 1,290 (39%) controls had ever used OCs, corresponding to an OR of 1.2 (95% CI 1.0 to 1.4). There was no relation with duration of use, age at first use, or use before first birth. The OR was significantly increased for current OC users (OR = 1.5, 95% 1.0 to 2.1), but declined with increasing time since stopping (OR = 1.1 for > 10 years since stopping). The association was stronger for papillary cancers (OR = 1.6 for current users) than for other histologic types. No significant heterogeneity was observed across studies or geographic areas. Eight studies had data on HRT, for a total of 1,305 cases and 2,300 controls: 110 (8%) cases and 205 (9%) controls reported ever using HRT (OR = 0.8; 95% CI 0.6 to 1.1). The ORs were 1.6 (95% to 0.9 to 2.9) for use of fertility drugs, and 1.5 (95% CI 1.1 to 2.1) for lactation suppression treatment. CONCLUSIONS: The studies considered in these analyses include most of the epidemiological data on the role of exogenous hormone use in the etiology of thyroid cancer, and they provide reassuring evidence on the absence of an association of practical relevance. The moderate excess risk in current OC users, if not due to increased surveillance for thyroid masses among OC users, is similar to that described for breast cancer, and would imply a role of female hormones on thyroid cancer promotion. There was no indication of increased thyroid cancer risk 10 or more years after discontinuing OC use.

Adenocarcinoma, Papillary↗
PubMed1999

A pooled analysis of case-control studies of thyroid cancer. I. Methods.

OBJECTIVE: Because the etiology of thyroid cancer is not well described, we conducted a pooled analysis of all published case-control studies, as well as two identified unpublished studies. This paper describes the major characteristics of the 14 studies included in the analysis, as well as the statistical methods employed. Four studies were conducted in the United States (1 each in Washington State, California, Connecticut and Hawaii), 8 in Europe (3 in Sweden, 2 in Norway, 1 in Switzerland, 1 in Italy and 1 in Greece), and 2 in Asia (1 in China and 1 in Japan). METHODS: The original datasets were obtained and restructured in a uniform format. Data on socio-demographic characteristics, anthropometric measures, smoking and alcohol consumption, history of benign thyroid diseases and of other selected medical conditions and treatments, family history of cancer and of benign thyroid conditions, occupation, residence in endemic goitre areas, and dietary habits were analyzed. For women, we also analyzed menstrual and reproductive factors and use of female hormones. Radiotherapy and, in Japan, exposure to the A-bombs were considered as potential confounding factors. RESULTS: A total of 2,725 cases (2,247 females and 478 males) and 4,776 controls (3,699 females and 1,077 males) were included in this study. Of the cases, 79% were classified as papillary thyroid carcinomas, 14% as follicular, 2% medullary, 1% anaplastic, 1% other histologies, and 3% histological type unknown. Each of the datasets was checked for outliers and consistency. Data were analysed separately by study center, gender, and the two major histologic types (papillary, follicular). Frequency tables and simple statistics were computed for each variable under study. Conditional logistic regression was used to compute odds ratios. For matched studies, the original matching was preserved, whereas, for unmatched ones, five-year age groups were used for matching. Study-specific analyses were computed, and then the data from all the studies were pooled conditioning on study. Heterogeneity between studies, geographic areas and study designs was assessed, and the modifying effect of age was also evaluated.

Adenocarcinoma, Follicular↗
PubMed1999

A pooled analysis of case-control studies of thyroid cancer. II. Menstrual and reproductive factors.

OBJECTIVE: It has been suggested that female hormones, and hence menstrual and reproductive factors, play a role in thyroid cancer etiology. Epidemiological data, however, are limited and inconsistent, partly because of the small number of cases included in each study. To clarify the etiology of thyroid cancer, we conducted a pooled analysis of original data from 14 case-control studies, 4 from the United States, 2 from Asia, and 8 from Europe. METHODS: This analysis included a total of 2,247 female cases of thyroid cancer (80% papillary) and 3,699 control women. Pooled odds ratios (OR) were estimated using logistic regression, conditioning on study and (i) matching sets for individually matched studies, or (ii) quinquennia of age for the other studies. Additional terms for age and history of radiation exposure were included in the regression equations. RESULTS: The OR per year of later menarche was 1.04 (95% confidence interval (CI) 1.0-1.1). Compared to premenopausal women, the OR was 1.3 for women with natural menopause, and 1.8 for those with artificial menopause, but the studies were heterogeneous and the association may be due, at least in part, to diagnostic or ascertainment bias. Parity, spontaneous or induced abortions and history of infertility were not associated with thyroid cancer risk. The OR was above unity in women reporting later age at first birth (OR = 1.1, 95% CI 1.0-1.3 for 5-year delay) and higher in the first years after a birth. CONCLUSIONS: The associations of menstrual and reproductive factors with thyroid cancer risk were generally weak, but appeared stronger among women diagnosed with thyroid cancer at younger ages.

Adenocarcinoma, Papillary↗
PubMed1999

A pooled analysis of case-control studies of thyroid cancer. IV. Benign thyroid diseases.

OBJECTIVE: To obtain more precise estimates of the association between thyroid cancer and benign thyroid diseases and to elucidate the role of potential confounders or effect modifiers. METHODS: The original data from 12 case-control studies from the United States, Asia, and Europe were pooled. Based on 2,094 women and 425 men with cancer of the thyroid and, respectively, 3,248 and 928 control subjects, odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained by conditional regression models, conditioning on study and age at diagnosis, and adjusting for age and radiotherapy. RESULTS: A history of hypothyroidism was not associated with cancer risk (pooled ORs = 0.9, 95% confidence interval, CI: 0.7-1.3 in women and 1.7, 95% CI: 0.3-11.7 in men). ORs for hyperthyroidism were 1.4 (95% CI: 1.0-2.1) in women and 3.1 (95% CI: 1.0-9.8) in men. In women, however, risk was lower in the absence of or after allowance for history of goiter. Pooled ORs for a history of goiter were 5.9 (95% CI: 4.2-8.1) in women and 38.3 (95% CI: 5.0-291.2) in men. Risk for a history of benign nodules/adenomas was especially high (OR = 29.9, 95% CI: 14.5-62.0, in women; 18 cases versus 0 controls in men). The excess risk for goiter and benign nodules/adenomas was greatest within 2-4 years prior to thyroid cancer diagnosis, but an elevated OR was present 10 years or more before cancer. CONCLUSIONS: Goiter and benign nodules/adenomas are the strongest risk factors for thyroid cancer, apart from radiation in childhood.

Adenoma↗
PubMed1999

SEARCH international case-control study of childhood brain tumours: role of index pregnancy and birth, and mother's reproductive history.

A series of co-ordinated population-based case-control studies of childhood brain tumours (CBT) was undertaken under the auspices of the Surveillance of Environmental Aspects Related to Cancer in Humans (SEARCH) programme of the International Agency for Research on Cancer (IARC) to evaluate, inter alia, the risk in relation to characteristics of the index pregnancy and birth, and maternal reproductive history. Subjects comprised 1218 cases aged 0-19 years and 2223 controls. Risk estimates were calculated by unconditional logistic regression, adjusted for age, sex, centre and mother's years of schooling, for all types of CBT combined as well as for four groups defined by histopathology (astrologlial tumours, primitive neuroectodermal tumours of the brain, 'other glial' tumours and 'other histological types') and for five age groups (0-1, 0-4, 5-9, 10-14, 15-19 years). Use of anaesthetic 'gas' was associated with an increased risk of CBT (OR = 1.5, 95% CI [1.1, 2.0]), apparent in children aged 0-4 years (OR = 2.4, 95% CI [1.4, 4.1]) and for astroglial tumours (OR = 1.6, 95% CI [1.1, 2.2]) with non-significantly increased relative risks for each of the other histological groups. However, not all centre-specific relative risks were elevated. No other aspect of the index pregnancy, delivery and early neonatal period or of the mother's previous reproductive history was associated with risk for CBT.

Adolescent↗