Diet and colon cancer: assessment of risk by fiber type and food source.

How fiber in the diet is related to the development of colon cancer was assessed in a population-based study conducted on 231 cases and 391 controls in Utah between 1979 and 1983. Crude fiber consistently decreased risk associated with colon cancer in both males [odds ratio (OR) = 0.4] and females (OR = 0.5). Dietary fiber, as analyzed by the method of A. S. Bitner, and neutral detergent fiber were not consistently related to colon cancer risk. Of the noncellulose polysaccharides examined, mannose and galactose were protective against cancers in the ascending colon in males (ORs = 0.5 and 0.3, respectively), whereas galactose and uronic acid were protective against cancers in the ascending colon in females (ORs = 0.5). Highest quartiles of intake of fruits and vegetables were also associated with a decreased risk of colon cancer in males (ORs = 0.3 and 0.6, respectively) and in females (ORs = 0.6 and 0.3, respectively) compared with lowest quartile of intake, whereas high intake of grains was not protective.

Food-consumption trends between adolescent and adult years and subsequent risk of prostate cancer.

A population-based, case-control study of prostate cancer in Utah was used to assess reported food-consumption patterns for the adolescent and adult years. Men reported eating eggs, whole milk, butter, white bread, cereals, and candy less frequently and red meat, fish, low-fat milk, cheese, yogurt, ice cream, margarine, fruits and vegetables, and whole-wheat bread more frequently as adults, indicating that diets changed in the hypothesized direction to correspond to national changes in food-consumption practices. Men who consumed a diet high in saturated fatty acids as adults were at a slightly increased risk of developing aggressive prostate cancer after adjusting for adolescent diet (odds ratio 1.8 comparing high with low intakes), whereas men who consumed a diet high in saturated fatty acids as adolescents were not at increased risk of developing these tumors after controlling for a diet high in saturated fatty acids as adults (odds ratio 1.1).

Collinear nutrients and the risk of colon cancer.

The relationship between colon cancer risk and the relative contributions of fat and caloric intake are assessed. A lack of consensus exists regarding the role of each of these dietary factors in the development of colon cancer. This lack of agreement originates from the high correlations between the nutrients, as well as the manner in which researchers treat these dietary variables in their analyses. Four proposed methods are evaluated which attempt to address the collinearity problem in nutritional epidemiology: (1) exclude one or more collinear variables, (2) use the proportion of calories consumed attributable to each dietary component, (3) use a regression-adjustment approach to purge the collinearity correlated nutrients, and (4) ridge regression. Diagnostic tests are reported which assess the degree of collinearity on data collected for a case-control study of colon cancer conducted in Utah between 1979 and 1983. Using logistic regression analyses, we apply each of these methods to case-control data. We find that the risks associated with fat and caloric consumption are extremely sensitive to a priori analytic decisions made by epidemiologist about the underlying collinearity problem.

Diet and survival of patients with colon cancer in Utah: is there an association?

The extent to which diet influenced colon cancer survival was examined in 411 colon cancer cases identified in Utah between 1976 and 1981 using data from two population based case-control studies. After adjustment by proportional hazards regression models for the effects of tumour stage, age, sex, and religion, the hazard rate ratios (HRR) comparing highest to lowest quartile of intake for total calories, fat and protein were 0.60, 0.81 and 0.66 respectively, with the effect of calories being greatest for short-term survival (less than or equal to 24 months), HRR = 0.49. By contrast, the highest quartile of dietary fibre intake was associated with decreased survival (HRR = 1.53) when compared with the lowest quartile. More extensive studies are needed to verify these findings and to identify mechanisms underlying these associations.

Marital adjustment among housestaff and new attorneys.

Previous reports have suggested that physicians' marriages may be adversely affected by the stresses of the profession. Some social scientists, however, question the view that demanding careers are the primary cause of poor marital adjustment and suggest instead that such careers may actually invigorate a marriage. This study, involving 116 housestaff physicians, 106 new attorneys, and the spouses of both groups, identified the factors that significantly affected their marital adjustments. No difference in marital adjustments was found between housestaff and attorneys or between the two spouse groups. In general, the spouses had higher marital adjustment scores than did the professionals, and the women professionals had higher scores than did the men professionals. The two most important factors associated with adjustment were the perceived level of emotional support received from one's spouse for one's career and the level of such support given to one's spouse for his or her career. The results suggest that housestaff and new attorneys are as satisfied with their marriages as are the other populations in which the same marital inventory has been used.

The association between dietary intake and reported history of Candida vulvovaginitis.

The association between dietary intake and the history of Candida vulvovaginitis was evaluated in 166 women who had a history of Candida vulvovaginitis in the past 5 years (cases) and in 207 women without such a history (total population), as well as in 74 women with five or more episodes in the past 5 years and 125 women with no history of Candida vulvovaginitis. Women were interviewed about their demographic data, past medical and sexual history, and their history of vaginal or pelvic infections. An extensive dietary history was taken to determine each woman's usual adult dietary intake. Results indicate associations between total caloric intake, carbohydrates, and fiber and a history of Candida vulvovaginitis. The results were not altered by controlling for age, body mass index, smoking, use of oral contraceptives, and sexual activity variables. These results suggest several dietary constituents may influence susceptibility to Candida vulvovaginitis infections. A follow-up prospective study, using culture confirmation of Candida infection, is needed.

Coffee consumption and the risk of cancer of the exocrine pancreas: a case-control study in a low-risk population.

Data from a population-based, case-control study of 149 cases of cancer of the exocrine pancreas (excluding insulinomas) and 363 controls were used to test the hypothesis that coffee consumption increased the risk of cancer of the exocrine pancreas. Because of the high mortality from cancer of the pancreas, all information was obtained from proxy respondents for cases and controls. Increased risk was present for coffee drinkers [odds ratio (OR) = 2.38], cigarette smokers (OR = 2.27), and alcohol users (OR = 1.60), but the effect for alcohol disappeared after adjustment for cigarette use. Risk increased with the amount of coffee drunk with an OR of 2.38 in the those having at least 50,000 lifetime cups. This gradient was present in both men and women, and in cigarette smokers and nonsmokers. Increased risk was present for users of regular and decaffeinated coffee, but the risk was higher for users of decaffeinated coffee than users of regular coffee. Cigarette smoking, after controlling for coffee consumption, was an independent risk factor for pancreatic cancer, with odds ratios in the heaviest smokers of 2.71 (95% confidence interval = 1.41-5.21.

Misclassification of exposure in a case-control study: the effects of different types of exposure and different proxy respondents in a study of pancreatic cancer.

This investigation addressed three questions about misclassification in a case-control study of risk factors for pancreatic cancer in which all exposure data were obtained from proxy respondents. These questions were: (1) To what degree was misclassification dependent on the type of exposure? (2) To what degree did misclassification vary by the type of proxy? (3) What was the magnitude of the effect of proxy misclassification on odds ratios measured across several levels of exposure? To answer these questions, we interviewed 163 control (index) subjects and next-of-kin (proxy) respondent pairs. Each of the controls and their respective proxies reported the control's use of coffee, cigarettes, and alcohol and weekly exposure to beef, milk, bacon, fruits, and vegetables. Nonspouse proxies misclassified exposures more than spouse proxies with the exception of cigarettes. Cigarette use was the most accurately reported exposure, followed by alcohol, coffee, and foods. For nondifferential misclassification between cases and controls, the slope of a dose-response curve was decreased from 6.6% to 100% depending on the exposure and the type of proxy respondent. Investigators conducting studies using proxy respondents need to recognize that misclassification is a function of multiple factors, including both the type of exposures under study and the type of proxies available.

Lifestyle and blood pressure levels in male twins in Utah.

Healthy male monozygotic (MZ) and dizygotic (DZ) twin pairs (MZ pairs = 77; DZ pairs = 88) were studied to assess the effect of dietary intake, physical activity, physical fitness, body mass index (BMI), sum of the triceps and subscapular skinfold measurements, alcohol and caffeine consumption, and smoking patterns on blood pressure. Data on physical activity, detailed dietary intake, medical history, and demographics were obtained from a questionnaire. A bicycle ergometer was used to estimate level of fitness; other medical information was ascertained from physical examination. After normalizing the study variables, intraclass correlations for BMI and the sum of the triceps and subscapular skinfold measurements were higher in MZ than in DZ twin pairs (BMI: MZ r = 0.76, DZ r = 0.48; skinfolds: MZ r = 0.73, DZ r = 0.28), as were VO2max(MZ r = 0.63, DZ r = 0.25) and post-bike heart rate (MZ r = 0.69, DZ r = 0.19). Both systolic (SBP) and diastolic blood pressure (DBP) had high heritability estimates (SBP = 0.60, and DBP = 0.66). Using factor analysis, four major lifestyle factors were identified and categorized as: 1) dietary intake; 2) a factor heavily weighted by cigarette smoking, alcohol and caffeine consumption; 3) fatness; 4) physical activity and physical fitness. Adjustment for these factors did not alter heritability estimates for either SBP or DBP.

Sexual activity, contraception, genital infections, and cervical cancer: support for a sexually transmitted disease hypothesis.

A case-control study was conducted in Utah between 1984 and 1987 to examine risk factors for cervical cancer. Interviews were completed with 266 histologically confirmed carcinoma in situ and invasive squamous cell cervical cancer cases who were categorically matched by age to 408 controls. Among the factors identified as altering risk for cervical cancer, after adjustment for age, education, church attendance, and cigarette smoking, were: having numerous sex partners (odds ratio (OR) = 8.99 for 10 or more partners); the current mate having several sex partners (adjusted OR for 10 or more partners = 8.62); using foam or jelly as a contraceptive method (OR, adjusted for number of sex partners, = 0.44); reported Trichomonas infection (OR, adjusted for number of sex partners, = 2.10); and herpes simplex virus type 2 infection as determined by 2:1 neutralization index values above 100 (OR = 2.70). A protective effect was noted from the use of diaphragms (OR = 0.67) or condoms (OR = 0.53) in women who reported more than one sex partner. These data support the hypothesis that cervical cancer is a sexually transmitted disease.

Validity of cigarette smoking habits in three epidemiologic studies in Utah.

Utah has lower incidence and mortality for many smoking-related forms of cancer and heart disease. It is an important epidemiologic question to assess whether the population attributable risk associated with cigarette smoking in this low-risk population is biased from under-reporting because of societal pressures not to smoke. To answer this question, we compared reported cigarette use to serum cotinine values in three different epidemiologic study designs. Included in these analyses were data from men interviewed for a cross-sectional study of dietary intake and hormones, women interviewed as a part of a case-control study of cervical cancer, and men interviewed in conjunction with a cardiovascular disease and hypertension family follow-up study. Cross-sectional study participants reported accurate cigarette usage 93.8% of the time; case-control participants accurately reported cigarette use 98.5% of the time; participants interviewed in the family cohort study correctly reported usage 82.8% of the time. Most inaccurate reporting of smoking was by exsmokers being followed for a disease known to be linked to smoking. The low attributable risk of smoking related to diseases in Utah is not from underreporting of cigarette smoking, and makes Utah an ideal population to examine other risk factors for diseases where smoking increases risk.

Nutrient intake and ovarian cancer.

A case-control study was conducted in Utah between 1984 and 1987 to evaluate the effects of nutrient intake on risk of developing ovarian cancer. Detailed dietary intake information was available from 85 first primary ovarian cancer cases and 492 population-based controls. Calories, fat, protein, fiber, and vitamins A and C did not appreciably alter the risk of developing ovarian cancer. However, high intake of beta-carotene appears to confer protection against ovarian cancer (odds ratio = 0.5, 95% confidence interval 0.3-1.0) after adjusting for age, number of pregnancies, and the body mass index of weight/height.

Adult dietary intake and prostate cancer risk in Utah: a case-control study with special emphasis on aggressive tumors.

A population-based case-control study in Utah of 358 cases diagnosed with prostate cancer between 1984 and 1985, and 679 controls categorically matched by age and county of residence, were interviewed to investigate the association between dietary intake of energy (kcal), fat, protein, vitamin A, beta-carotene, vitamin C, zinc, cadmium, selenium, and prostate cancer. Dietary data were ascertained using a quantitative food-frequency questionnaire. Data were analyzed separately by age (45-67, 68-74) and by tumor aggressiveness. The most significant associations were seen for older males and aggressive tumors. Dietary fat was the strongest risk factor for these males, with an odds ratio (OR) of 2.9 (95 percent confidence interval [CI] 1.0-8.4) for total fat; OR = 2.2 (CI = 0.7-6.6) for saturated fat; OR = 3.6 (CI = 1.3-9.7) for monounsaturated fat; and OR = 2.7 (CI = 1.1-6.8) for polyunsaturated fat. Protein and carbohydrates had positive but nonsignificant associations. Energy intake had an OR of 2.5 (CI = 1.0-6.5). In these older men, no effects were seen for dietary cholesterol, body mass, or physical activity. There was little association between prostate cancer and dietary intake of zinc, cadmium, selenium, vitamin C, and beta-carotene. Total vitamin A had a slight positive association with all prostate cancer (OR = 1.6, CI = 0.9-2.4), but not with aggressive tumors. No associations were found in younger males, with the exception of physical activity which showed active males to be at an increased but nonsignificant risk for aggressive tumors (OR = 2.0, CI = 0.8-5.2) and beta-carotene which showed a nonsignificant protective effect (OR = 0.6, CI = 0.3-1.6). The findings suggest that dietary intake, especially fats, may increase risk of aggressive prostate tumors in older males.

The impact of a multidisciplinary approach on caring for ventilator-dependent patients.

OBJECTIVE: To determine the clinical and financial outcomes of a highly structured multidisciplinary care model for patients in an intensive care unit (ICU) who require prolonged mechanical ventilation. The structured model outcomes (protocol group) are compared with the preprotocol outcomes. DESIGN: Descriptive study with financial analysis. SETTING: A twelve-bed medical-surgical ICU in a non-teaching tertiary referral center in Ogden, Utah. STUDY PARTICIPANTS: During a 54 month period, 469 consecutive intensive care patients requiring mechanical ventilation for longer than 72 hours who did not meet exclusion criteria were studied. INTERVENTIONS: A multidisciplinary team was formed to coordinate the care of ventilator-dependent patients. Care was integrated by daily collaborative bedside rounds, monthly meetings, and implementation of numerous guidelines and protocols. Patients were followed from the time of ICU admission until the day of hospital discharge. MAIN OUTCOME MEASURES: Patients were assigned APACHE II scores on admission to the ICU, and were divided into eight diagnostic categories. ICU length of stay, hospital length of stay, costs, charges, reimbursement, and in-hospital mortality were measured. RESULTS: Mortality in the preprotocol and protocol group, after adjustment for APACHE II scores, remained statistically unchanged (21-23%). After we implemented the new care model, we demonstrated significant decreases in the mean survivor's ICU length of stay (19.8 days to 14.7 days, P= 0.001), hospital length of stay (34.6 days to 25.9 days, P=0.001), charges (US$102500 to US$78500, P=0.001), and costs (US$71900 to US$58000, P=0.001). CONCLUSIONS: Implementation of a structured multidisciplinary care model to care for a heterogeneous population of ventilator-dependent ICU patients was associated with significant reductions in ICU and hospital lengths of stay, charges, and costs. Mortality rates were unaffected.

Cigarette smoking and exposure to passive smoke are risk factors for cervical cancer.

Personal cigarette smoking and exposure to passive smoke as risk factors for cervical cancer were examined in a population-based, case-control study conducted in Utah. Personal cigarette smoking was found to increase the risk of cervical cancer, after adjusting for age, educational level, church attendance, and sexual activity. The adjusted risk estimate associated with being a current smoker was 3.42 (95% confidence interval [Cl], 2.10 to 5.57); for having smoked for 5 or more pack-years, it was 2.81 (95% Cl, 1.73 to 4.55); and for having smoked at least 100 lifetime cigarettes, it was 2.21 (95% Cl, 1.44 to 3.39). The adjusted risk estimate (also adjusted for actual cigarettes smoked) associated with passive smoke exposure for 3 or more hours per day was 2.96 (95% Cl, 1.25 to 7.03). Risk from passive smoking was greater in women who were not smokers (odds ratio, 3.43; 95% Cl, 1.23 to 9.54) than in women who smoked (odds ratio, 2.59; 95% Cl, 0.23 to 29.24).

Dietary vitamins A, C, and E and selenium as risk factors for cervical cancer.

The relation between cervical cancer and dietary intake of vitamins A, C, and E, beta-carotene, and selenium was examined in a population-based case-control study in Utah. Cervical cancer cases (n = 266) and population-based controls (n = 408) were interviewed between 1984 and 1987. Protective effects were observed for vitamins A, C, and E and beta-carotene but were attenuated by age, level of education, and lifetime cigarette use. Associated risk (comparing highest with lowest quartiles of intake) went from 0.53 (crude) to 0.71 (adjusted) for vitamin A; from 0.55 (crude) to 0.82 (adjusted) for beta-carotene; from 0.45 (crude) to 0.55 (adjusted) for vitamin C; from 0.58 (crude) to 0.60 (adjusted) for vitamin E; and from 0.95 (crude) to 0.70 (adjusted) for selenium. Adjustment for number of sex partners and church attendance, factors significantly related to cervical cancer risk, only slightly attenuated these adjusted risk estimates.

Tobacco, alcohol, coffee, and caffeine as risk factors for colon cancer in a low-risk population.

We used data from a population-based case-control study to examine how use of tobacco products and consumption of alcohol, coffee, and caffeine relate to colon cancer in Utah. We hypothesized that low use of these substances is one factor contributing to the low colon cancer incidence in Utah and could help explain the low risk associated for colon cancer with being a member of the Church of Jesus Christ of Latter-day Saints. In females, we observed little or no increase in risk of colon cancer from smoking cigarettes or from consumption of alcohol, caffeine, or coffee. Males who used pipes, however, experienced an increased risk for colon cancer (OR = 4.1, 95% CI = 1.3-12.3). Risk for colon cancer associated with alcohol use was greatly attenuated after adjusting for caffeine and pipe use in males; males who consumed higher levels of caffeine during the two to three years prior to the interview were at higher risk than males who consumed low levels of caffeine (OR = 2.0, 95% CI = 1.0-4.2); similar associations were observed for coffee consumption. Nonuse of these substances could explain the low colon cancer incidence rates observed in members of the Church of Jesus Christ of Latter-day Saints and Utah males.