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L W Pickle

Publications and source records attributed to L W Pickle.

At least 37 records · Page 2Linked to original sources
PubMed1990

Occupation and pancreatic cancer risk in Louisiana.

To study the relation of occupational exposures and pancreatic cancer, we evaluated data from males (198 cases and 209 controls) participating in a hospital-based case-control study conducted in a high-risk area of Louisiana between 1979 and 1983. The questionnaire obtained information on lifetime occupational history, as well as dietary, smoking, and drinking habits and demographic characteristics. After adjustment for smoking and dietary patterns, white collar occupations showed consistent elevations in risk, whereas associations for other occupations were in general unremarkable. Although not significantly elevated, risks for truck drivers (OR = 1.7) and those with long-term employment in machine repair or as mechanics were suggestive (OR = 2.5). No association was found for jobs in oil refining or oil and gas extraction (ORs were 0.5 and 0.4, respectively), although risks were slightly elevated for long-term workers in the chemical processing industry (OR = 1.2). While these associations deserve further study, our findings are consistent with results of other studies which do not suggest that occupational exposures are important determinants of pancreatic cancer.

Adenocarcinoma↗
PubMed1989

Effect of smoking and alcohol consumption on laryngeal cancer risk in coastal Texas.

Data from case-control studies of respiratory cancer conducted in the Texas Gulf Coast region between 1975 and 1980 were used to examine the effects of smoking and alcohol on laryngeal cancer risk. Analyses were limited to living white males, aged 30-79, which included 151 histologically confirmed incident laryngeal cancer cases and 235 population-based controls. A dose-dependent effect for cigarette smoking was observed, with odds ratios ranging from 4.4 for ever smoking up to one-half pack daily, to 10.4 for smoking more than two packs per day. Risks were strongest for current smokers and declined markedly following smoking cessation. Higher risks were associated with smoking nonfiltered than filtered cigarettes. No significantly elevated risks were associated with the use of other tobacco products. Odds ratios for alcohol beverages did not increase linearly with increasing use; instead risks were twofold for consumption of four or more drinks weekly. Patterns of risk associated with beer and hard liquor were not consistent and few participants drank wine. Although the data were sparse, a dose-response effect for alcohol intake was suggested for tumors of the supraglottis (n = 23), while for nonsupraglottic cases, alcohol risks were elevated but did not increase beyond those observed for four drinks per week. Predicted risks for the combined effects of cigarette and alcohol use were intermediate between an additive and multiplicative form of interaction.

Adult↗
PubMed1989

Lung cancer in motor exhaust-related occupations.

The association between employment in motor exhaust-related occupations and the risk for lung cancer was examined in 2,291 male cases of lung cancer and 2,570 controls in data pooled from three U.S. case control studies carried out by the National Cancer Institute between 1976 and 1983. Most analyses were limited to subjects providing direct, in-person interviews, including 1,444 cases and 1,893 controls. For those providing direct interviews and employed 10 years or more in motor exhaust-related (MER) occupations, the age, smoking, and study area adjusted odds ratio (OR) for lung cancer was 1.5 (95% CI = 1.2-1.9). Risk was elevated for truck drivers (OR = 1.5; 95% CI = 1.1-1.9) and for other MER occupations (OR = 1.4; 95% CI = 1.1-2.0). The odds ratios associated with MER employment of 10+ years were 1.6 (95% CI = 1.2-2.1) for whites and 1.4 (95% CI = 0.9-2.1) for nonwhites; 1.2 (95% CI = 0.7-2.0) [corrected] for those with possible exposure to other recognized or reported lung carcinogens; and 1.6 (95% CI 1.2-2.1) for those without such exposure. The 50% excess risk for lung cancer associated with employment in motor exhaust-related occupations could not be explained by greater use of cigarettes or by other occupational exposures among these workers.

Aged↗
PubMed1989

The distribution of debrisoquine metabolic phenotypes and implications for the suggested association with lung cancer risk.

Debrisoquine hydroxylation exhibits wide inter-individual variation in Caucasian populations. After similar doses of the drug, extensive metabolizers excrete up to several hundred times more of the urinary metabolite 4-hydroxy-debrisoquine than do poor metabolizers. The phenotypes have traditionally been defined by the metabolic ratio (MR), or the molar ratio of debrisoquine to its chief metabolite recovered in an aliquot of an eight hour urine sample, after a test dose of the drug. Deficient metabolism is inherited as an autosomal recessive condition. We have reanalyzed previously published data from a study of lung cancer patients and controls using a computerized optimization method to more accurately estimate the parameters describing the three phenotypic distributions. Using these new distributions to categorize controls, we show that Hardy-Weinberg conditions are now fulfilled. When the newly defined phenotype parameters are employed to assign the phenotypes of cases and controls, a highly significant difference in phenotype distribution between cases and controls is still observed. This result supports the hypothesis that the debrisoquine metabolic phenotype may be associated with lung cancer susceptibility.

Chromatography, Gas↗
PubMed1989

The new United States Cancer Atlas.

Published in 1975, the Atlas of Cancer Mortality for U.S. Counties: 1950-1969 proved useful in identifying geographic patterns, especially clusters of high-rate areas, that have stimulated further epidemiologic study of specific cancer sites. These data have been updated to include population and mortality statistics through 1980. Our new atlas presents static maps of area-specific mortality rates for each decade from 1950 to 1980 among white males and females for 33 cancer sites, along with dynamic maps illustrating the trends in these rates over time. Although the geographic distribution of mortality rates has become more uniform for most cancer sites, clusters of high-rate areas have persisted for several common tumors. However, some new patterns have appeared, notably the emergence of several high-rate areas for lung cancer among women. Possible explanations for the geographic peculiarities of cancer are considered, based on the results of correlation and analytic studies prompted by the earlier maps. These successive studies indicate the value of monitoring mortality statistics on a small-area scale as a strategy for generating etiologic clues and targeting epidemiologic research, although one must be mindful of geographic fluctuations in diagnostic and reporting practices, survival rates, and migration patterns.

Chronology as Topic↗
PubMed1988

Proportion of lung cancers in males, due to occupation, in different areas of the USA.

Occupational data from 5 case-control studies in the United States involving 2,973 male cases and 3,210 controls were analyzed to estimate the percentage of lung cancer attributable to well-known and suspected lung carcinogens. The studies were conducted in areas heterogeneous in terms of industrial activities. The percentage of lung cancers attributable to occupations entailing potential exposure to well-recognized carcinogens ranged, by study area, from 3 to 17%. The further inclusion of occupational groups with suspect carcinogenic exposures changed these estimates very little. Exclusion of data derived from next-of-kin interviews influenced the estimates of attributable risks, but not in a systematic fashion. The estimates also varied according to ethnic group, smoking status and birth cohort, with higher values in non-whites, non-smokers and among members of more recent birth cohorts. Possible errors in exposure classification, which may make these estimates conservative, are discussed.

Humans↗
PubMed1988

Dietary vitamins A and C and lung cancer risk in Louisiana.

The authors describe the results of a hospital-based incident case-control study of lung cancer conducted in a high-risk region of southern Louisiana from January 1979 through April 1982. Dietary intake of carotene, retinol, and vitamin C was estimated from food frequency questionnaires administered to 1253 cases and 1274 controls. An inverse association was found between level of carotene intake and lung cancer risk, and this protective effect was specific for squamous and small cell carcinoma (odds ratio [OR] = 0.84, 95% confidence interval: 0.64-1.09, high intake). A stronger protective effect for these tumors was associated with dietary vitamin C intake (OR = 0.65, 0.50-0.87, high intake). A significant inverse gradient in risk with retinol intake was limited to adenocarcinoma (OR = 0.64, 0.44-0.94, high intake) and more pronounced among blacks.

Adult↗
PubMed1988

Case-control study of diet and mesothelioma in Louisiana.

Data were analyzed from a case-control interview study of malignant mesothelioma in Louisiana, which gathered information on usual diet and on lifetime occupational exposure to asbestos. Thirty-seven patients with malignant mesothelioma of the pleura (n = 32) or peritoneum (n = 5) were matched to controls according to age, sex, race, and factors related to case ascertainment (hospital and date of diagnosis, or parish and date of death). Twenty-one of the 37 cases were judged by masked occupational review to have been exposed to asbestos (57%), compared to seven of 37 controls (19%). Seven additional cases and 10 additional controls had occupational histories suggestive of asbestos exposure. With regard to usual diet before illness, cases reported less frequent consumption of homegrown produce (p = 0.005), cruciferous vegetables (p = 0.005), and all vegetables combined (p = 0.09) than did the controls. An estimate of usual carotene intake was also significantly lower in cases (p = 0.03). Dose-dependent reductions in risk were seen with increasing consumption of vegetables, especially cruciferous vegetables (p for trend = 0.013). These associations were not explained by differences in asbestos exposure as measured by the occupational review. The results indicate that consumption of vegetables or some vegetable-related constituent may have a protective effect on developing mesothelioma.

Adult↗
PubMed1988

Occupational risk factors for laryngeal cancer on the Texas Gulf Coast.

Analyses are reported from a case-control interview study of incident laryngeal cancer on the Gulf Coast of Texas. Study subjects were 183 white men with squamous cell carcinoma of the larynx and 250 frequency matched controls. Occupational exposures were examined controlling for potential confounding by cigarette smoking and alcohol consumption. Significantly elevated risks were seen for men employed in the public services industry [transportation, communication, utilities, sanitary service; relative risk (RR), 1.6]; in metal fabricating (RR, 2.1), construction (RR, 1.7), and maintenance (RR, 2.7) occupations; and for workers potentially exposed to paint (RR, 1.8) and diesel or gasoline fumes (RR, 1.5). Elevated risks of border-line significance were seen for men employed as woodworkers/furniture makers (RR, 8.1) and for those with occupational exposure to asbestos (RR, 1.5). When asbestos was categorized by intensity of exposure, a significant positive gradient was found.

Alcohol Drinking↗
PubMed1988

Life-style risk factors for pancreatic cancer in Louisiana: a case-control study.

A hospital-based, incident case-control study of pancreatic cancer was conducted between 1979 and 1983 in parallel with similarly designed studies of lung and stomach cancers in high-risk areas of Louisiana. To evaluate life-style practices, including diet, the authors pooled controls from the three studies, and then excluded subjects with diet-altering chronic diseases. When the 363 cases were compared with the 1,234 identified controls, significantly elevated risks were found among persons with Cajun ancestry, especially in rural areas. Among current smokers, a significant twofold risk was associated with moderate (16-25 cigarettes per day) and heavy (greater than or equal to 26 cigarettes per day) consumption, while ex-smokers showed no consistent pattern of risk. After adjustment for potential confounding by smoking, diet, and demographic factors, the risk of pancreatic cancer was unrelated to use of alcoholic beverages or coffee. Pork products and rice were conspicuous as dietary risk factors, each showing a positive dose-response effect, whereas fruit consumption exerted a protective influence.

Aged↗
PubMed1988

Carotene intake and the risk of laryngeal cancer in coastal Texas.

Between 1976 and 1980, data were collected for a case-comparison study of laryngeal cancer in white males aged 30-79 years in six Texas counties using all histologically confirmed incident cases and a population-based comparison group. Dietary interviews were obtained from 151 living cases and 178 living comparison subjects. A significant inverse association (odds ratio (OR) = 2.1) was found between low carotene intake and the risk of laryngeal cancer, but no association was found with total vitamin A or retinol intake. The inverse association with carotene intake was strongest among those who had stopped smoking 2-10 years before (OR = 5.9). The same risk for vitamin A intake was found by using a short list of foods based on contribution to variation in intake as was found by using a longer list based on per cent contribution to total intake. Definition of carotene as that which comes only from plant sources gives an estimate similar to a more complex method that takes into account carotene derived from both plant and animal sources.

Adult↗
PubMed1987

Cytogenetics in hereditary malignant melanoma and dysplastic nevus syndrome: is dysplastic nevus syndrome a chromosome instability disorder?

Analysis of peripheral blood lymphocyte Giemsa-banded karyotypes was performed on 163 family members from 13 melanoma-prone families. Patients were classified regarding the presence of cutaneous melanoma and dysplastic nevi (a well characterized melanoma precursor), and each karyotype was scored for the number of cells containing the following: major structural, minor structural, and numerical abnormalities. No clonal cytogenetic abnormalities were observed. Cutaneous malignant melanoma and dysplastic nevi syndrome patients each had increased abnormalities of all types combined, compared with pooled controls (i.e., normal family members, and spouses; respectively, chi 2 = 6.02, p = 0.01; chi 2 = 5.29, p = 0.02). There was a statistically significant p-value for major structural abnormalities for melanoma patients and numerical abnormalities for the dysplastic nevi patients. Minor structural abnormalities did not differ in any of the groups. In addition, studies of ultraviolet induced sister chromatid exchange, in vitro tetraploidy, and extended prophase banding were performed on a limited number of patients. No significant differences between cases and controls were observed in these tests. Our data suggest that a chromosome instability abnormality may contribute to the pathogenesis of hereditary melanoma.

Adult↗
PubMed1987

Effects of ear type and weather on the hospital prevalence of canine otitis externa.

A retrospective study of 8975 dogs seen at 15 university veterinary medical teaching hospitals in North America (1975 to 1978) found that dogs with pendulous ears and heavy ear canal hair had significantly (P less than 0.01) more otitis externa than dogs with other ear types. Dogs with erect ears, regardless of the amount of ear canal hair, had less risk (P less than 0.01) of the disease than mongrel dogs. Direct evidence is available for the first time showing that monthly variations in ambient temperature, rainfall and relative humidity explain, to a large extent, the monthly variations in the hospital prevalence of canine otitis externa in different geographic regions.

Animals↗
PubMed1986

The relation of passive smoking to lung cancer.

To evaluate the role of passive smoking in the development of lung cancer among nonsmokers, data were pooled from three large incident case-control interview studies. Ninety-nine lung cancer cases and 736 controls never used any form of tobacco. Overall the adjusted odds ratio for lung cancer among nonsmokers ever living with a smoker was 0.8 (95% confidence interval, 0.5-1.3) rising to 1.2 among those exposed for 40 or more years. Persons living with a spouse who smoked cigarettes were at increased risk (adjusted odds ratio, 1.5; 95% confidence interval, 0.8-2.8). When adjusted for age and gender, there was a significant trend in risk with increasing amounts smoked per week by the spouse (P = 0.05) and with cumulative pack-years of exposure (P = 0.03). This effect was limited to females, especially older women whose husbands were heavy smokers. The elevated risk associated with spouse smoking was restricted to squamous and small cell carcinomas (odds ratio, 2.9; 95% confidence interval, 0.9-9.3), which provides additional evidence linking passive smoking to lung cancer.

Adenocarcinoma↗
PubMed1985

Indicator foods for vitamin A assessment.

Epidemiological interview studies examining the association between vitamin A and cancer at various sites have been hampered by restricted time available for interview; consequently, studies have included varying lists of food items or broad food groups, thus making comparability of results difficult. To identify a standardized list of indicator foods that adequately assess total vitamin A intake, we examined the 24-hour dietary recall of 13,201 adults who participated in the First National Health and Nutrition Examination Survey (NHANES I) from 1971 to 1974. Food items reportedly consumed were ranked by contribution to overall (aggregated) intake in various subpopulations by an index of vitamin A contribution, which reflected the frequency of consumption, portion size, and vitamin A concentration (IUs/100 g). A comparison of these ranks identified certain food items that had a relative contribution to vitamin A intake which varied by sex/race group, season of interview, age, or region of the country; income level had little effect on the food rankings. The top-ranking 50 foods were sufficient to correctly classify 80%-90% of the individuals into low-, moderate-, and high-consumer categories. The major contributing foods for any subpopulation examined included both retinol (e.g., dairy products, liver) and carotenoid sources of vitamin A (e.g., certain fruits and vegetables) in addition to items (e.g., mixed tomato and cheese dishes) not included in earlier questionnaire studies. Recommendations are made for future questionnaires designed to assess vitamin A.

Adolescent↗