Biomedical subjects

Wendy Cozen

Publications and source records attributed to Wendy Cozen.

41 records · Page 3Linked to original sources

PubMed2004

Comparison of pesticide levels in carpet dust and self-reported pest treatment practices in four US sites.

Epidemiologic studies have used both questionnaires and carpet dust sampling to assess residential exposure to pesticides. The consistency of the information provided by these two approaches has not been explored. In a population-based case-control study of non-Hodgkin's lymphoma, carpet dust samples were collected from the homes of 513 control subjects in Detroit, Iowa, Los Angeles, and Seattle. The samples were taken from used vacuum cleaner bags and analyzed for 30 pesticides. Interviewers queried subjects about the types of pests treated in their home using a detailed questionnaire accompanied by visual aids. Geographic variations in pesticide levels were generally consistent with geographic differences in pest treatment practices. Los Angeles residents reported the most treatment for crawling insects, fleas/ticks, and termites, and Los Angeles dust samples had the highest levels of propoxur, chlorpyrifos, diazinon, permethrin, and chlordane. Iowa had the most treatment for lawn/garden weeds, and also the highest levels of 2,4-dichlorophenoxyacetic acid and dicamba. Although Seattle had the highest proportion of subjects treating for lawn/garden insects, the lawn/garden insecticides were higher in other sites. Multivariate linear regression revealed several significant associations between the type of pest treated and dust levels of specific pesticides. The strongest associations were between termite treatment and chlordane, and flea/tick treatment and permethrin. Most of the significant associations were consistent with known uses of the pesticides; few expected associations were absent. The consistency between the questionnaire data and pesticide residues measured in dust lends credibility to both methods for assessing residential exposure to pesticides. The combined techniques appear promising for epidemiologic studies. Interviewing is the only way to assess pesticide exposures before current carpets were in place. Dust sampling provides an objective measure of specific compounds to which a person may have been exposed through personal use of a pesticide or by drift-in or track-in from outside, and avoids recall bias.

Adult↗

PubMed2004

Risk of non-Hodgkin's lymphoma and family history of lymphatic, hematologic, and other cancers.

BACKGROUND: An elevated risk of developing non-Hodgkin's lymphoma (NHL) has been associated with a family history of NHL and several other malignancies, but the magnitude of risks and mechanisms are uncertain. METHODS: We used self-reported family history data from a recent multicenter U.S.-based case-control studies of NHL to evaluate familial aggregation of NHL with various hematolymphoproliferative and other cancers. Estimates of familial aggregation were obtained as hazard ratios (HR) that compare incidence of different cancers in first-degree relatives of NHL cases with that in the first-degree relatives of NHL controls. Limitations of the study included low participation rates (76% for cases and 52% for controls) and potential differential accuracy of recall. RESULTS: Risk of NHL was elevated in relatives of NHL cases [HR, 2.9; 95% confidence interval (95% CI), 0.95-8.53]; the aggregation seems to be stronger for siblings (HR, 7.6; 95% CI, 0.98-58.8) and for male relatives (HR, 6.2; 95% CI, 0.77-50.0). Risk of Hodgkin's lymphoma seems to be also elevated among relatives of early-onset (<50 years) NHL cases (HR, 3.2; 95% CI, 0.88-11.6). Evaluation of family history of other cancers provided modest evidence for an increased risk of melanoma of the skin (HR, 2.9; 95% CI, 1.08-7.75), pancreatic cancer (HR, 2.1; 95% CI, 0.96-4.43), stomach cancer (HR, 1.8; 95% CI, 0.91-3.63), and prostate cancer (HR, 1.3; 95% CI, 0.87-1.99). CONCLUSIONS: These results are consistent with previous findings of familial aggregation of NHL, Hodgkin's lymphoma, and a few other cancers. The pattern of male-specific and sibling-specific familial aggregation of NHL we observed, if confirmed, may shed new light on the possible mechanisms that underlie familial aggregation of the disease.

Adult↗

PubMed2003

IL-6 levels and genotype are associated with risk of young adult Hodgkin lymphoma.

Identical twins of young adult Hodgkin lymphoma case subjects are much more likely to develop the disease compared with fraternal twins of case subjects, suggesting a genetic determinant. Interleukin 6 (IL-6) levels are increased in patients with Hodgkin lymphoma and are correlated with a poor prognosis. We hypothesized that a heritable abnormality in IL-6 regulation may predispose to young adult Hodgkin lymphoma. We obtained blood specimens from 88 young adult Hodgkin lymphoma case subjects and their twins as well as from 87 matched control subjects. IL-6 was measured from unstimulated peripheral blood mononuclear cell (PBMC) supernatant with enzyme-linked immunosorbent assays (ELISAs) and compared by using analysis of covariance. Unaffected identical twins of case subjects (surrogate case subjects) had a 87.8% higher IL-6 level compared with matched control subjects (mean difference, +483.7 pg/mL, P =.04). Analysis of the IL-6 174G>C promoter polymorphism genotypes showed that risk decreased with an increasing number of C alleles (P =.01). The CC (low secreting) genotype was associated with a decreased risk of young adult Hodgkin lymphoma relative to the GG (high secreting) genotype (odds ratio [OR] =.29; P =.03). Risk was decreased for both nodular sclerosis and other subtypes. Persons with genetically determined lower IL-6 levels may be less susceptible to young adult Hodgkin lymphoma.

Adolescent↗

PubMed2002

Galactose-1-phosphate uridyl transferase (GALT) genotype and phenotype, galactose consumption, and the risk of borderline and invasive ovarian cancer (United States).

OBJECTIVE: Previous studies have suggested that high levels of galactose consumption and/or low levels of galactose-I-phosphate uridyl transferase (GALT) activity may result in an increased risk of epithelial ovarian cancer. Similarly, some have reported that carriers of the N314D (asparagine at codon 314 replaced by aspartate) GALT polymorphism, which can be associated with low GALT activity, may have a higher risk of ovarian cancer. We examined these issues as part of a large case-control study of ovarian cancer conducted in Los Angeles between 1992 and 1998. METHODS: A total of 1,439 histologically confirmed borderline and invasive ovarian cancer cases among English-speaking non-Asian women were ascertained through the population-based cancer registry for Los Angeles County and completed in-person interviews were obtained from 689 of these (78% of cases approached). Controls consisted of 645 English-speaking non-Asian women with at least one intact ovary matched to cases on race/ethnicity (African-American, Latina, non-Latina White), date of birth (+/-3 years), and neighborhood of residence. Interviewer-administered questionnaires included information on reproductive factors, exogenous hormone use, medical history, and diet. Dietary information for the year before each case's diagnosis (and the same period for her matched control) was obtained using a self-administered food-frequency questionnaire. Blood samples were obtained from 452 controls, 136 cases with borderline ovarian cancer, and 312 cases with invasive ovarian cancer. The N314D polymorphism was characterized using PCR-RFLP and GALT enzyme activity, and was determined for a sample of the subjects with GALT genotype using an erythrocyte-based radioactive enzyme assay. RESULTS: We found no effect of N314D GALT genotype on the risk of borderline ovarian cancer (odds ratio (OR)=0.91; 95% confidence interval (CI)=0.54-1.6) or invasive ovarian cancer (OR=0.78; 95% CI= 0.53-1.2). Neither did we observe a relationship between GALT activity or lactose/galactose intake and risk of borderline or invasive ovarian cancer. Among N314D carriers, galactose consumption was associated with an increased risk of borderline (OR = 2.7, p = 0.01), but not invasive (OR = 1.2, p = 0.34), ovarian cancer; however, this result was based on only 24 N314D-positive borderline cases. CONCLUSIONS: Differences in galactose intake and GALT metabolism do not contribute significantly to the risk of ovarian cancer. There is some evidence that galactose intake may play a role in the development of borderline ovarian cancer among women who carry the uncommon GALT N314D polymorphism. More data are needed if this latter suggestion is to be definitively addressed.

Adult↗

PubMed2002

The occurrence of chronic disease and other conditions in a large population-based cohort of native Californian twins.

We describe the prevalence of chronic diseases and conditions in a large cohort of twins, which has been developed to facilitate studies of the role of genetics and environment in the development of disease. The California Twin Program (CTP) comprises twins born in California between 1908 and 1982. Birth records from all multiple births (256,616 in total) were linked (multiple times between 1990 and 2001) with the California Department of Motor Vehicles (DMV) roster of licensees to obtain address information. The linkages have revealed 161,109 matches and, because of less complete DMV records in some years, were less successful in older females than in all others. To date over 51,000 of these twins have completed a detailed 16-page mailed risk factor questionnaire. Based on estimates of numbers of individuals receiving a questionnaire, our crude response rates are as high as 63.6% (among females currently in their 50s), with an overall crude response rate of 37.9%. Similar to our previous report regarding the first 42,000 twins, the current group who have completed the questionnaire are representative of the population from which they were drawn (in terms of age, sex, race and residential distribution). Self-reported disease frequencies are provided, along with current estimates of future cancer incidence and mortality rates likely to be observed in the group. We outline our plans for cohort expansion, additional studies using the cohort, and future plans for inviting collaboration.

Adolescent↗