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Susan Preston-Martin

Publications and source records attributed to Susan Preston-Martin.

At least 19 recordsLinked to original sources
PubMed2006

Maternal medication use and the risk of brain tumors in the offspring: the SEARCH international case-control study.

N-nitroso compounds (NOC) have been associated with carcinogenesis in a wide range of species, including humans. There is strong experimental data showing that nitrosamides (R(1)NNO.COR(2)), a type of NOC, are potent neuro-carcinogens when administered transplacentally. Some medications are a concentrated source of amides or amines, which in the presence of nitrites under normal acidic conditions of the stomach can form NOC. Therefore, these compounds, when ingested by women during pregnancy, may be important risk factors for tumors of the central nervous system in the offspring. The aim of the present study was to test the association between maternal use of medications that contain nitrosatable amines or amides and risk of primary childhood brain tumors (CBT). A case-control study was conducted, which included 1,218 cases and 2,223 population controls, recruited from 9 centers across North America, Europe and Australia. Analysis was conducted for all participants combined, by tumor type (astroglial, primitive neuroectodermal tumors and other glioma), and by age at diagnosis (< or =5 years; >5 years). There were no significant associations between maternal intake of medication containing nitrosatable amines or amides and CBT, for all participants combined and after stratification by age at diagnosis and histological subtype. This is the largest case-control study of CBT and maternal medications to date. Our data provide little support for an association between maternal use of medications that may form NOC and subsequent development of CBT in the offspring.

Adolescent↗
PubMed2006

Effects of human immunodeficiency virus on protracted amenorrhea and ovarian dysfunction.

OBJECTIVE: To characterize ovarian failure and prolonged amenorrhea from other causes in women who are both human immunodeficiency virus (HIV) seropositive and seronegative. METHODS: This was a cohort study nested in the Women's Interagency HIV Study, a multicenter U.S. study of HIV infection in women. Prolonged amenorrhea was defined as no vaginal bleeding for at least 1 year. A serum follicle stimulating hormone more than 25 milli-International Units/mL and prolonged amenorrhea were used to define ovarian failure. Logistic regressions, chi2, and t tests were performed to estimate relationships between HIV-infection and cofactors with both ovarian failure and amenorrhea from other causes. RESULTS: Results were available for 1,431 women (1,139 HIV seropositive and 292 seronegative). More than one half of the HIV positive women with prolonged amenorrhea of at least 1 year did not have ovarian failure. When adjusted for age, HIV seropositive women were about three times more likely than seronegative women to have prolonged amenorrhea without ovarian failure. Body mass index, serum albumin, and parity were all negatively associated with ovarian failure in HIV seropositive women. CONCLUSION: HIV serostatus is associated with prolonged amenorrhea. It is difficult to ascertain whether the cause of prolonged amenorrhea is ovarian in HIV-infected women without additional testing. LEVEL OF EVIDENCE: II-2.

Adolescent↗
PubMed2006

Descriptive epidemiology of vestibular schwannomas.

Vestibular schwannomas, commonly termed acoustic neuromas, arise from the vestibular branch of the eighth cranial nerve (acoustic nerve) and are benign, slow-growing brain tumors that negatively impact patient quality of life. They are thought to account for the majority of intracranial nerve sheath tumors. To describe incidence rate patterns and trends of primary nerve sheath tumors of the brain/CNS and the subset of vestibular schwannomas in two population-based incidence registries, data were obtained from 11 Central Brain Tumor Registry of the United States (CBTRUS) collaborating state registries and the Los Angeles County Cancer Surveillance Program (LACCSP) (1975-1998). Average annual incidence rates were tabulated by age, gender, race, year, and region and were age-adjusted to the year 2000 U.S. standard population. Multiplicative Poisson regression models were used to compare trends in primary nerve sheath tumors of the brain/CNS overall and in subgroups, including vestibular schwannomas, controlling for age, gender, race, microscopic confirmation, and region. Joinpoint regression analysis was used to identify any sharp changes in incidence over time. The overall incidence of primary nerve sheath tumors of the brain/CNS was 1.1 per 100,000 person-years (CBTRUS, 1995-1999 and LACCSP, 1995-1998). The incidence of vestibular schwannomas was similar for both data sets: 0.6 per 100,000 person-years (CBTRUS, 1995-1999) and 0.8 per 100,000 person-years (LACCSP, 1995-1998). Moreover, the incidence of primary nerve sheath tumors of the brain/CNS overall (CBTRUS, 1985-1999 and LACCSP, 1975-1998) and of vestibular schwannomas (CBTRUS, 1992-1999 and LACCSP, 1992-1998) increased over time. However, the incidence of benign schwannomas in sites other than the acoustic nerve either decreased (CBTRUS, 1992-1999) or experienced no significant change (LACCSP, 1992-1998). While improvements in diagnosis and reporting may explain some of these trends, further consideration of potential etiologic factors may be warranted.

Adolescent↗
PubMed2005

A population-based description of glioblastoma multiforme in Los Angeles County, 1974-1999.

BACKGROUND: There have been reports that the incidence rates of brain tumors have increased over the past few decades, but most have considered all brain tumors together. The authors analyzed the pattern of glioblastoma multiforme (GBM) occurrence in Los Angeles County, California to shed light on the incidence and descriptive epidemiology of this type of brain tumor. METHODS: Data were obtained from the Los Angeles County Cancer Surveillance Program. Incidence rates were analyzed by gender, race, age at diagnosis, period of diagnosis (1974-1981, 1982-1988, or 1989-1999), and socioeconomic status (SES). In addition, data were stratified according to anatomic subsite. A multivariate model describing changes in rates by each of these variables was constructed. RESULTS: Age-specific incidence rates (ASIR) rose sharply after age 30 years. The peak ASIR was at age 70-74 years in males and at age 75-79 years in females. The age-adjusted incidence rate (AAIR) of GBM increased from 1974 to 1999 by an estimated 2.4% per year among males and 2.8% per year among females. Overall, males had a 60% increased risk of brain tumors compared with females. Males had a higher incidence of GBM compared with females at each anatomic subsite except the posterior fossa. The largest male:female ratio occurred in the occipital lobes. Non-Latino whites had the highest incidence rates (2.5 per 100,000) followed by Latino whites (1.8 per 100,000), and blacks (1.5 per 100,000). After 1989, compared with the period before magnetic resonance imaging (MRI) was available, there was an increase in GBM incidence rates among those with of higher SES that was most pronounced in females. The incidence of GBM was highest for frontal lobe tumors and for tumors that involved two or more lobes (overlapping tumors), followed by tumors in the temporal and parietal lobes. In the multivariate analysis, year of diagnosis, SES, gender, race (Latino but not black), site, and age at diagnosis all were important predictors of incidence rate. CONCLUSIONS: GBM incidence increased in Los Angeles County over the last 30 years and especially after 1989, suggesting that the introduction of MRI may have contributed to the increase. Individuals older than age 65 years experienced the greatest increase in incidence over time. Older age, male gender, higher SES, and non-Latino white race increased the risk of GBM. Previously unreported incidence rates for GBM among Latino whites were significantly lower than among non-Latino whites but were intermediate between non-Latino whites and blacks.

Adult↗
PubMed2005

Prescription drug use and risk of acute myeloid leukemia by French-American-British subtype: results from a Los Angeles County case-control study.

Chemotherapy is a well-established risk factor for acute myeloid leukemia (AML) but little is known about other prescription drugs and AML risk. We report data from a population-based Los Angeles County study in which 299 matched case-control pairs had complete data on prescription drug use and 88% of cases were subtyped according to the French-American-British (FAB) criteria. Cases were diagnosed between 1987 and 1994. Prescription nonsteroidal anti-inflammatory drug (NSAID) use for at least 4 weeks in the 2 to 10 years before diagnosis was associated with decreased risk (odds ratio = 0.5, 95% confidence interval=0.3, 1.0; p=0.04) with dose-response most evident for FAB subtype M2 (OR = 0.6, CI: 0.1, 2.9 for duration < or =6 months; OR = 0.2, CI: 0.0, 1.6 for >6 months). For subtype M4, ORs increased with increasing duration of benzodiazepine use in the 2 to 10 years before diagnosis (OR = 1.5, CI: 0.3, 9.0 for < or =6 months vs. OR = 5.0, CI: 0.6, 42.8 for >6 months). These results suggest that prescription drugs other than chemotherapy may have FAB subtype-specific effects on AML risk.

Adult↗
PubMed2005

Occupational risk factors for low grade and high grade glioma: results from an international case control study of adult brain tumours.

The majority of suspected occupational risk factors for adult brain tumours have yet to be confirmed as etiologically relevant. Within an international case-control study on brain tumours, lifelong occupational histories and information on exposures to specific substances were obtained by direct interviews to further investigate occupational risk factors for glioma. This is one of the largest studies of brain tumours in adults, including 1,178 cases and 1987 population controls from 8 collaborating study centres matched for age, gender and centre. All occupational information, was aggregated into 16 occupational categories. In a pooled analysis, odds ratios (OR), adjusted for education, were estimated separately for men and women and for high-grade glioma (HGG) and low-grade glioma (LGG), focusing especially on 6 categories defined a priori: agricultural, chemical, construction, metal, electrical/electronic and transport. For men, an elevated OR of glioma associated with the category "metal" (OR = 1.24, 95% CI 0.96-1.62) was seen, which appeared to be largely accounted for by LGG (OR = 1.59, 95% CI 1.00-2.52). For the other 5 occupational categories, no elevated risks for glioma were observed. For women the only noteworthy observation for the 6 a priori categories was an inverse association with the "agriculture" category (OR = 0.60, 95% CI 0.36-0.99). Apart from the 6 major categories, women working in food production or food processing (category "food") showed an increased OR of 1.95 (95% CI 1.04-3.68). None of the 20 substance groups was positively associated with glioma risk. Although some other point estimates were elevated, they lacked statistical significance. The results do not provide evidence of a strong association between occupational exposures and glioma development.

Adult↗
PubMed2005

A review: dietary and endogenously formed N-nitroso compounds and risk of childhood brain tumors.

Maternal dietary exposure to N-nitroso compounds (NOC) or to their precursors during pregnancy has been associated with risk of childhood brain tumors. Cured meat is one source of exposure to dietary NOC and their precursors. Most epidemiological studies that have examined the role of maternal consumption of cured meats during pregnancy have found a significant positive association between maternal intake of cured meat and the risk of childhood brain tumor (CBT). NOC consist of two main groups, N-nitrosamines and N-nitrosamides. The carcinogenicity profiles of NOC suggest that N-nitrosamides rather than N-nitrosamines are the compounds that may be associated with CBT and that they should be investigated more closely in epidemiological studies. We present a review of the chemical and carcinogenic properties of NOC in connection with the findings of case-control studies. This approach may be helpful in determining the essential information that must be collected in future epidemiological studies on CBT.

Brain Neoplasms↗
PubMed2005

Prior hospitalization for epilepsy, diabetes, and stroke and subsequent glioma and meningioma risk.

We conducted a case-control study to evaluate the preclinical association between epilepsy, diabetes, and stroke and primary adult brain tumors. We first identified all 1,501 low-grade glioma, 4,587 high-grade glioma (HGG), and 4,193 meningioma cases reported to the Swedish Cancer Registry from 1987 to 1999. Next, controls (137,485) were randomly selected from the continuously updated Swedish Population Registry and matched to cases diagnosed that year on age and sex. Finally, cases and controls were linked to the Swedish Hospital Discharge Registry (1969-1999). We found that > or =8 years before HGG diagnosis (or control reference year) there was an elevated risk of HGG among people discharged with epilepsy [odds ratio (OR), 3.01; 95% confidence interval (95% CI), 1.73-5.22]. Two to 3 years before HGG diagnosis, this risk increased (OR, 5.33; 95% CI, 3.58-7.93) and was especially strong among people ages <55 years (OR, 13.49; 95% CI, 6.99-25.94). During this 2- to 3-year prediagnostic period, we also found an increased risk of HGG among people discharged with meningitis (OR, 3.02; 95% CI, 1.06-8.59) or viral encephalitis (OR, 12.64; 95% CI, 2.24-71.24). Results are similar for glioblastoma multiforme, low-grade glioma, and meningioma. In contrast, risk of HGG among people discharged with diabetes or stroke does not increase until year of brain tumor diagnosis. The occurrence of excess epilepsy > or =8 years before HGG diagnosis suggests a relatively long preclinical phase, but excess diabetes or stroke appear late in HGG development.

Adult↗
PubMed2004

Household water source and the risk of childhood brain tumours: results of the SEARCH International Brain Tumor Study.

BACKGROUND: The period in utero is a time of increased vulnerability. Offspring of pregnant women exposed to carcinogenic substances in drinking water may be more likely to develop cancer. We examined whether household water source and the presence of nitrates or nitrites in residential water were associated with increased risks of childhood brain tumours (CBT). METHODS: We used data from a multicentre, case-control study with maternal information on residential water source, and nitrate/nitrite levels of tap water measured by dipstick. Subjects included 836 CBT cases and 1485 controls from five countries. RESULTS: The risks of CBT associated with reliance on well water (versus public water) during pregnancy varied widely, with significantly increased risks noted in two (of seven) regions and a decreased risk observed in one region. CBT risk did not increase with increasing nitrate levels. However, our results based on tap water tested in the pregnancy residences suggest the risk of astrocytoma may be associated with increasing levels of nitrite (odds ratio [OR] = 4.3, 95% CI: 1.4, 12.6 for nitrite levels of 1-<5 mg/l nitrite ion; OR = 5.7, 95% CI: 1.2, 27.2 of nitrite > or =5 mg/l). CONCLUSIONS: These results should be interpreted with caution because women's recollection of water sources may have contained inaccuracies, and nitrate and nitrite measurements, available for only a portion of subjects, were often obtained years after the pregnancies occurred. However, our results suggest a need for closer evaluation of well water content in some regions and the possibility that a nitrite-related water exposure may be associated with CBT.

Astrocytoma↗
PubMed2004

Epidemiology of brain tumors in childhood--a review.

Malignant brain tumors are the leading cause of cancer death among children and the second most common type of pediatric cancer. Despite several decades of epidemiologic investigation, the etiology of childhood brain tumors (CBT) is still largely unknown. A few genetic syndromes and ionizing radiation are established risk factors. Many environmental exposures and infectious agents have been suspected of playing a role in the development of CBT. This review, based on a search of the medical literature through August 2003, summarizes the epidemiologic evidence to date. The types of exposures discussed include ionizing radiation, N-nitroso compounds (NOC), pesticides, tobacco smoke, electromagnetic frequencies (EMF), infectious agents, medications, and parental occupational exposures. We have chosen to focus on perinatal exposures and review some of the recent evidence indicating that such exposures may play a significant role in the causation of CBT. The scientific community is rapidly learning more about the molecular mechanisms by which carcinogenesis occurs and how the brain develops. We believe that advances in genetic and molecular biologic technology, including improved histologic subtyping of tumors, will be of huge importance in the future of epidemiologic research and will lead to a more comprehensive understanding of CBT etiology. We discuss some of the early findings using these technologies.

Animals↗
PubMed2004

Cancer risk among participants in the women's interagency HIV study.

BACKGROUND: The HIV epidemic has been associated with an increased incidence of specific cancers. However, less is known about cancers occurring in HIV-infected women than men. METHODS: To determine the risk of cancer among HIV-infected and at-risk HIV-uninfected women, cancer incidence data from the Women's Interagency HIV Study (WIHS) were compared with data from the population-based United States Surveillance, Epidemiology, and End Results (SEER) registry. Age- and race-adjusted standardized incidence ratios (SIRs) were computed and exact statistical tests were used to measure significance. RESULTS: Among the 1950 women participants (1554 HIV infected, 391 HIV uninfected, and 5 HIV seroconverters), 48 cancers were diagnosed during study follow-up. Among HIV-infected women, significantly (P < 0.05) increased incidence rates were observed for all cancer types (SIR = 1.9), Kaposi sarcoma (SIR = 213.5), non-Hodgkin lymphoma (NHL) (SIR = 19.0), and lung cancer (SIR = 6.3) when compared with SEER rates. Lung cancer incidence was also elevated (P = 0.07) among the HIV-uninfected women (SIR = 6.9), when compared with SEER rates, and was similar to the SIR for HIV-infected women. While the incidence rate of NHL among HIV-infected women was significantly lower during the era of highly active antiretroviral therapy (HAART) compared with the pre-HAART era (relative risk = 0.15, P = 0.005), the incidence of NHL among HIV-infected WIHS participants remained significantly higher than in the US population (SIR = 6.4, 95% CI = 1.3-15.5). CONCLUSION: In the HAART era, the higher rates of cancer among HIV-infected women, coupled with increased life expectancy, should lead to more intensive cancer screening and prevention efforts in this population.

Adult↗
PubMed2004

Alcohol consumption and risk of adult-onset acute myeloid leukemia: results from a Los Angeles County case-control study.

Few studies have examined the role of alcohol consumption in risk of adult acute myeloid leukemia (AML). Two previous case-control studies resulted in inconsistent findings. We report data from a Los Angeles County population-based case-control study in which 164 matched case-control pairs were asked about lifetime history of alcohol consumption and 136 cases were subtyped according to the French-American-British (FAB) criteria. Estimated categorical odds ratios (OR) adjusted for smoking and education were suggestive of a possible protective effect but trend tests were non-significant. Analyses by FAB subtype did not reveal subtype-specific associations but generally suffered from lack of power. Larger studies are needed to more thoroughly investigate the relationship between alcohol consumption and AML risk.

Acute Disease↗
PubMed2004

The Los Angeles Latino Eye Study: design, methods, and baseline data.

OBJECTIVE: To describe the study design, operational strategies, procedures, and baseline characteristics of the Los Angeles Latino Eye Study (LALES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Latinos. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, California. METHODS: A detailed interview and eye examination were performed on each eligible participant. The interview included an assessment of demographic, behavioral, and ocular risk factors and health-related and vision-related quality of life. The eye examination included a measurement of visual acuity, intraocular pressure, and visual fields; fundus and optic disc photography; a detailed anterior and posterior segment examination; and measurement of blood pressure, glycosylated hemoglobin levels, and blood glucose levels. MAIN OUTCOME MEASURES: Prevalence of visual impairment, blindness, cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration constitute the study's primary outcome variables. Secondary outcomes include odds ratios for risk factors associated with eye disease, health-related quality of life, and vision-related quality of life. Response rates and baseline characteristics are presented. RESULTS: Of the 7789 individuals eligible for LALES, 6357 (82%) had a clinical examination; an additional 524 completed only an in-home interview. The majority of participants were female (58%), the average (+/- standard deviation) age was 54.9 (+/-10.8) years, and 80.0% were of Mexican origin and 0.4% self-identified as American Indian or Alaskan Native. The age distribution of LALES participants was similar to that of Latinos of Mexican origin in the rest of the United States. CONCLUSION: The LALES has recruited Latinos 40 and older for an ophthalmic epidemiologic study. The LALES cohort will provide information about the prevalence and risk factors of ocular disease in the largest and fastest growing minority in the United States.

Adult↗
PubMed2003

Cohort studies of association between self-reported allergic conditions, immune-related diagnoses and glioma and meningioma risk.

An inverse association between self-reported allergies and glioma and meningioma risk, has been previously observed in case-control studies. Approximately 27% (median) of the information on both glioma and meningioma in these studies, however, is collected from proxy respondents. In fact, the odds ratios (OR) among previous brain tumor studies are inversely related to the proportion of proxy respondents (Pearson correlation coefficient = -0.94; 95% CI = -1.00 to -0.65); this correlation suggests bias. We therefore constructed 3 cohorts based on the Swedish Twin, Hospital Discharge, and Cancer Registries. In Cohorts I (14,535 people developed 37 gliomas and 41 meningiomas) and II (29,573 people developed 42 gliomas and 26 meningiomas) median time from self-report of allergies to brain tumor diagnosis was 15.4 years. Cohort III, which overlaps with Cohorts I and II (52,067 people developed 68 gliomas and 63 meningiomas), was linked to the Swedish Hospital Discharge Registry where pre-brain tumor immune-related discharge diagnoses were recorded. Allergies are inversely associated with glioma risk in Cohort I (Hazard ratio [HR] = 0.45; 95% CI = 0.19-1.07) and among high grade (III and IV, HR = 0.45; 95% CI = 0.11-1.92) but not low grade (I and II, HR = 2.60; 95% CI = 0.86-7.81) gliomas in Cohort II. In Cohort III, immune-related discharge diagnoses are also inversely associated with glioma (HR = 0.46; 95% CI = 0.14-1.49). There is no strong evidence against (and some for) the hypothesis that allergies reduce glioma risk.

Adult↗
PubMed2003

A pooled analysis of case-control studies of thyroid cancer: cigarette smoking and consumption of alcohol, coffee, and tea.

OBJECTIVE: To analyze the role of smoking, alcohol, coffee and tea in relation to thyroid cancer, we conducted a pooled analysis of 14 case-control studies conducted in the United States, Europe, and Asia. METHODS: The sample consisted of 2725 thyroid cancer cases (2247 females, 478 males) and 4776 controls (3699 females, 1077 males). Conditional logistic regression with stratification on study, age at diagnosis, and gender was used to compute odds ratios and 95% confidence intervals. RESULTS: Thyroid cancer risk was reduced in persons who had ever smoked. The relationship was more pronounced in current smokers (OR = 0.6, 95% CI = 0.6-0.7) than former smokers (OR = 0.9, 95% CI = 0.8-1.1). There were significant trends of reduced risk with greater duration and frequency of smoking. For consumption of wine and beer, there was a significant trend of decreasing thyroid cancer risk (p = 0.02) that was not maintained after adjustment for current smoking (p = 0.12). Thyroid cancer risk was not associated with consumption of coffee or tea. These findings were consistent in both gender-specific and histology-specific (papillary and follicular) analyses. CONCLUSIONS: Pooled analyses of these geographically diverse case-control data indicate a reduced thyroid cancer risk associated with current smoking. A reduced risk associated with alcohol was eliminated after adjustment for smoking, and caffeinated beverages did not alter thyroid cancer risk.

Alcohol Drinking↗
PubMed2003

Farm-related exposures and childhood brain tumours in seven countries: results from the SEARCH International Brain Tumour Study.

A total of 1218 cases of childhood brain tumours (CBT) and 2223 control subjects from the general population were included in a population-based case-control study conducted in nine centres in seven countries. Mothers were asked about farm- or agriculture-related exposures. Significantly elevated odds ratios (OR) for CBT were associated with children's personal and maternal prenatal exposure while living on a farm with pigs (child OR = 1.7, mother OR = 2.3), horses (child OR = 1.6, mother OR = 1.8), dogs (child OR = 1.5, mother OR = 1.5) and cats (child OR = 1.5, mother OR = 1.7). Children who were exposed to pigs, horses and cats combined, while living on a farm, had a threefold elevated OR for CBT. Increased ORs for primitive neuroectodermal tumours (PNET) were associated with children's farm exposure to dogs (OR = 1.9) and cats (OR = 2.2), and maternal farm exposure to pigs (OR = 4.2). The OR for CBT was elevated (OR = 2.3) for children of mothers who had preconception/prenatal farm- or agriculture-related employment involving potential contact with animals, relative to no farm- or agriculture-related employment. In particular, increased ORs for CBT were observed for children of mothers who were employed as general farmers (OR = 4.1) or general farm workers (OR = 3.8). During the 5 years preceding the index child's birth, maternal exposures were related to CBT, relative to no maternal exposure to agricultural chemicals or animal products: fertilisers (OR = 1.8), pesticides (OR = 2.0), animal manure (OR = 2.0) and unprocessed wool (OR = 3.0). Our findings suggest that various farm-related exposures are positively associated with CBT and warrant further investigation into the public health importance of these associations.

Adolescent↗