Biomedical subjects

C C Nass

Publications and source records attributed to C C Nass.

4 recordsLinked to original sources

PubMed1992

Parental occupation and childhood astrocytoma: results of a case-control study.

Parental occupations were investigated as possible risk factors for astrocytoma, the most frequently occurring brain tumor in children. A case-control study of 163 pairs was performed. Cases under 15 years of age at diagnosis in 1980-1986 were identified through the tumor registries of eight hospitals in Pennsylvania, New Jersey, and Delaware. Controls were selected by random-digit dialing and were matched to cases on age, race, and telephone area code. Occupations before the child's conception, during the pregnancy, and after the child's birth were studied separately. We did not observe any strong associations. Significantly more fathers of cases were electrical or electronic repairmen, a subgroup of an occupational category previously associated with increased risk. An excess of case mothers employed as nurses was observed, which was significant for mothers of children diagnosed before 5 years of age. Elevated although not significant odds ratios were observed for some white collar and professional occupations in case parents; for paternal exposure to paint and paternal occupation in the paper and pulp mill industry, both in the period after the child's birth; and for maternal occupation as a hairdresser. The lack of strong associations may have resulted from low statistical power for some job groupings. Our study, unlike previous studies, focused on a single type of brain tumor: childhood astrocytoma. Thus our results suggest that some parental occupations associated with childhood brain tumors in previous studies may not be risk factors for childhood astrocytoma.

Adolescent↗

PubMed1991

Regression methods for estimating attributable risk in population-based case-control studies: a comparison of additive and multiplicative models.

A regression method that utilizes an additive model is proposed for the estimation of attributable risk in case-control studies carried out in defined populations. In contrast to previous multivariate procedures for the estimation of attributable risk, which have utilized logistic regression techniques to adjust for confounding factors, the model assumes an additive relation between the covariates included in the regression equation. As an empirical example, additive and logistic models were fitted to matched case-control data from a population-based study of childhood astrocytoma brain tumors. Although both models fitted the data well, the additive model provided a more satisfactory estimate of the risk attributable to multiple exposures, in the absence of significant additive interaction. In contrast to the results from the logistic model, the adjusted estimates of the risk attributable to each factor included in the additive model summed to the overall estimate for all of the factors considered jointly. Thus, the additive approach provides a useful alternative to existing procedures for the multivariate estimation of attributable risk when the additive model is determined to be appropriate on the basis of goodness-of-fit.

Astrocytoma↗

PubMed1990

Gestational and familial risk factors for childhood astrocytoma: results of a case-control study.

Gestational and familial risk factors were investigated for their association with astrocytoma, the most frequently occurring brain tumor in children. A case-control study of 163 matched pairs was performed. Cases under 15 years of age at diagnosis in 1980-1986 were identified through the tumor registries of 8 hospitals in Pennsylvania, New Jersey, and Delaware. Controls were selected by random digit dialing and were matched to cases for age, race, and telephone area code and exchange. Maternal antinausea medications increased the risk of childhood astrocytoma [OR (odds ratio) = 2.0, P = 0.04]. Cured meat consumption during pregnancy was more common among cases (OR = 1.9, P = 0.07), and a significant trend with increasing frequency of consumption was observed (P = 0.04). Results for gestational exposure to marijuana (OR = 2.8, P = 0.07) were of borderline significance. Gestational exposure to neurally active medications, alcohol, and tobacco were not risk factors. There was a significant trend for cases to be of higher birth weight (P = 0.03). Mental retardation (OR = 3.0, P = 0.04) and cancer (OR = 1.7, P = 0.02) in a relative of the child significantly increased the risk of astrocytoma. Significantly increased risks were observed for brain tumors in relatives of children 0-4 years of age at diagnosis (OR = 6/0, P = 0.04). A significant protective effect was observed for maternal history of miscarriage or stillbirth (OR = 0.5, P = 0.01). The results of this study suggest that some gestational and familial factors may increase the risk of childhood astrocytoma.

Adolescent↗

PubMed1989

Parental occupation and Wilms' tumor: results of a case-control study.

Parental occupational exposures for Wilms' tumor were investigated in a pair-matched case-control study. The timing of the exposures in relation to the child's conception and birth was studied, as were the two forms of Wilms' tumor: genetic (prezygotic origin) and nongenetic (postzygotic origin). Cases who were under 15 yr of age at diagnosis during 1970 to 1983 were identified through the registries of three main hospitals treating childhood cancer in the Greater Philadelphia area. Controls were selected by random digit dialing and were matched to cases on race, birth date, and telephone area code and exchange. Because of a low participation rate among blacks, results are reported only for the 88 white matched pairs whose parents participated in telephone interviews. Children whose fathers held jobs in a job cluster that consisted mostly of machinists and welders were at significantly increased risk. The increase was highest for preconception exposure (odds ratio = 5.3, P = 0.006). The effect of preconception exposure was higher for the 26 genetic cases than for the 42 nongenetic cases. The other 20 cases were excluded from the subgroup analyses for various reasons. Further analyses did not elucidate an exposure common to machinists and welders that might explain the findings.

Adult↗