Michael J. Symons

Fruit and vegetable consumption and prevention of cancer: the Black Churches United for Better Health project.

OBJECTIVES This study assessed the effects of the Black Churches United for Better Health project on increasing fruit and vegetable consumption among rural African American church members in North Carolina. METHODS Ten counties comprising 50 churches were pair matched and randomly assigned to either intervention or delayed intervention (no program until after the follow-up survey) conditions. A multicomponent intervention was conducted over approximately 20 months. A total of 2519 adults (77.3% response rate) completed both the baseline and 2-year follow-up interviews. RESULTS The 2 study groups consumed similar amounts of fruits and vegetables at baseline. AT the 2-year follow-up, the intervention group consumed 0.85 (SE = 0.12) servings more than the delayed intervention group (P < .0001). The largest increases were observed among people 66 years or older (1 serving), those with education beyond high school (0.92 servings), those widowed or divorced (0.96 servings), and those attending church frequently (1.3 servings). The last improvement occurred among those aged 18 to 37 years and those who were single. CONCLUSIONS The project was a successful model for achieving dietary change among rural African Americans.

Stages of change and psychosocial correlates of fruit and vegetable consumption among rural African-American church members

Purpose. This study examined the relationship between stages of change, other psychosocial factors, and fruit and vegetable (F&V) consumption among rural African-Americans participating in a 5 a Day study. Design. The cross-sectional design assessed associations between F&V intake, stage of change, self-efficacy, beliefs, barriers, and social support. Setting. Participants were surveyed by telephone. Subjects. Subjects were 3557 adult church members (response rate, 79.1%), aged 18 and over from 10 North Carolina counties. Measures. A seven-item food frequency measured F&V intake. Stage of change was measured using four items; other psychosocial variables were measured using Likert scales. Chi-square tests and analysis of variance were used in statistical analyses. Results. The majority of participants (65 %) were in the preparation stage of change. Individuals in action/maintenance consumed an average of 6.5 daily F&V servings compared to 3.3 to 3.5 servings for those in precontemplation, contemplation, and preparation. Self-efficacy, social support, and belief about how many daily F&V servings are needed, were positively associated with stage. Barriers were most prevalent among precontemplators. Conclusions. The findings support the applicability of the stages-of-change model to dietary change among rural African-Americans. The relationship between stage, self-efficacy, social support, and barriers supports using a multicomponent intervention strategy.

FACTORS CONTRIBUTING TO THE POORER SURVIVAL OF BLACK AMERICANS DIAGNOSED WITH ORAL CANCER (UNITED STATES)

Objective: The purpose of this study was to identify factors that contribute to the poorer survival of blacks in the United States diagnosed with oral cancer.Methods: Data for 6338 whites and 1165 blacks diagnosed from 1988 to 1993 with squamous cell carcinoma of the oral cavity and pharynx were obtained from the National Cancer Institutes Surveillance, Epidemiology and End Results (SEER) program 1973–1993 Public-Use Database. The covariables were sex, age, geographic area, marital status, socioeconomic status (five census-tract measures), stage, anatomic site, grade, lymph node involvement, tumor size, and treatment. Hazard ratios were estimated with Cox regression.Results: Adjusted for age and geographic area, the hazard of death from oral cancer was 1.7 (95% confidence interval: 1.5–1.9) times greater among blacks than whites. The addition of the socioeconomic status (SES) variables to the model reduced the hazard ratio for race to 1.3 (1.0–1.7). Further adjustment by stage and treatment reduced the hazard ratio for race to 1.1 (0.9–1.4). In a model containing all covariables (except lymph node involvement and tumor size), the hazard ratio for race remained 1.1 (0.9–1.4). Analyses with the outcome death from any cause gave similar results.Conclusions: Lower SES, more advanced stage, and differences in treatment accounted for 86% of the excess hazard of death from oral cancer among blacks.

A comparison of the logistic risk function and the proportional hazards model in prospective epidemiologic studies

The logistic regression and proportional hazards models are each currently being used in the analysis of prospective epidemiologic studies examining risk factors in chronic disease applications. The advantages and disadvantages of each are yet to be fully described. However, a theoretical relationship between the two models has been documented. In this paper the conditions under which results from the two models approximate one another are described. It is shown that where the follow-up period is short and the disease is generally rare, the regression coefficients of the logistic model approximate those of the proportional hazards model with a constant underlying hazard rate. Since under the same conditions the likelihood functions approximate one another, the regression coefficients have similar estimated standard errors. Further, estimation of relative risk with these models is contrasted. These results are illustrated utilizing a previously published data set on metastatic cancer of the breast. With increasing follow-up time, the logistic regression coefficients become uncertain and less reliable.

On the utility of proportional mortality analysis.

Abstract The Standardized Mortality Ratio (SMR) is a commonly used epidemiologic tool for evaluating a test population with respect to a standard. Computation of the measure requires that the size and demographic composition of the test population-at-risk (PAR) be known. In the absence of this knowledge of the PAR, some have turned to evaluations based on proportional mortality rates, a method which is generally regarded as deficient because of the inability of relative measures to provide information about absolute rates. Often, the ratio of the cause-specific SMR to the underlying ‘force of mortality’ (i.e. the SMR for all causes) is of interest; this ratio is referred to herein as the relative SMR (RSMR). It is shown in this paper, both empirically and in a theoretical framework, that the RSMR is close in value to the (age) standardized proportional mortality ratio (SPMR), this closeness being expressible in the form of a ‘confidence interval’ involving the SPMR. Computation of the SPMR does not require knowledge of the PAR.

Soy Isoflavones: No Effects on Bone Mineral Content and Bone Mineral Density in Healthy, Menstruating Young Adult Women after One Year

Background: The effects of isoflavone-enriched soy protein on human bone mineral content (mass) and density in healthy, menstruating young adult females have not been examined in a comparative prospective investigation. Peri- and post-menopausal women have been reported to show beneficial effects of isoflavones on bone measurements. Therefore, young women may also be able to improve their accrual of peak bone mineral content (BMC) and bone mineral density (BMD) during the early adult years of bone consolidation with an isoflavone-enriched diet. Objectives: In this controlled, double-blind intervention, we tested the hypothesis that an isoflavone-rich soy protein diet increases BMC and BMD in young adult females over a period of one year in comparison to a control group receiving soy protein that has isoflavones removed. Design: Young healthy women of any ethnic background, 21 to 25 years of age, were divided into two groups, placebo (n = 13) and supplement (n = 15). The soy protein supplement was enriched with isoflavones (∼90 mg of total isoflavones/day), whereas the control protein diet was isoflavone-deficient, even though it contained the same amount of soy protein and other ingredients as the isoflavone-rich diet. Dual-energy x-ray absorptiometric (DXA) measurements of BMC and BMD were made at baseline and at 6 and 12 months. DXA estimates of body composition, including fat mass and lean body mass, were generated from whole-body BMC measurements. BMI was calculated as weight (kg) over height (m) squared. Physical activity was assessed, and three-day dietary records were taken at entry (baseline) and at 6 and 12 months. Results: No changes in BMD after 12 months were found in either the isoflavone-treated (treatment) group or the isoflavone-deficient (control) group. Other variables also remained essentially constant over the 12-month period, including normal menstrual patterns in both the treatment and control groups. Conclusions: The isoflavone-rich soy preparation had no effects on BMC and BMD over a 12-month period in young healthy adult females with normal menses. An isoflavone-rich supplement appears to have little or no effect on bone in young adult women with normal ovarian function, at least over this 12-month study period.

Reconstruction of Silica Exposure in the North Carolina Dusty Trades

The current occupational standard for quartz exposure is largely drawn from studies of the granite workers at Barre, Vermont. Since 1935, the North Carolina Dusty Trades program has accumulated data on work-place environmental conditions, occupational history and health status for persons exposed to silica in a broad range of mineral industries, including granite dimension stone. The environmental data have been collected with Greenburg-Smith and midget impingers and the respirable mass dust sampler. A procedure is presented to combine the results of these sampling methods and estimate exposure at the various jobs at each dusty trades plant. From an individuals occupational history, the environmental exposure estimates are used to formulate personal lifetime exposure summaries. The results of this procedure in the North Carolina granite industry compared well with historical data from Vermont granite sheds.

A method for monitoring the fertility of workers. 1. Method and pilot studies.

A method has been developed for monitoring male and female industrial workers and other persons exposed to environmental agents which may impair fertility. The essential feature of the method is its ability to distinguish the potential effects of occupational exposure from a multitude of other factors known to affect fertility. Information is collected primarily through use of a questionnaire which takes less than three minutes to complete and can be administered to persons of either sex. The advantages and limitations of the method are considered in the context of pilot studies at two small chemical plants and of a review of attempts to assess occupational effects on fertility from interviews or health records.

Mediators of depression among low-income, adolescent mothers of infants: A longitudinal perspective

The purpose of this study was to identify, using a life events perspective, Stressors and resources that mediate depression for adolescent mothers at the time of the birth of their child and at one year postpartum. The data for this study consisted of interviews with 157 low-income adolescent mothers age 12–18 at the birth of their child. They were selected from a larger prospective study of mothers of infants and stress. Multiple regression analyses revealed two key results that were consistent for the data obtained at birth and at one year postpartum. Predictors of depressive symptomatology and of a clinical syndrome of depression were similar. Also, Stressors generally were more important as mediators of depression than resources.

Worker exposures to chemical agents in the manufacture of rubber tires: Solvent vapor studies

Environmental sampling surveys have been conducted in ten large tire manufacturing plants across the U.S. to characterize the nature and intensity of current exposure to solvent vapors. These plants were chosen to represent a cross-section of the industry and include both old and new plants, plants of four different companies and plants with wide geographic distributions. A variety of organic solvents is used in the manufacture of tires and tubes; accordingly solvent vapors comprise one category of exposure for workers in specific Occupational Title Groups (OTGs). Approximately 1000 determinations of various solvent vapor components in air samples have been made with special emphasis on pentane, hexane, heptane, benzene and toluene vapor levels. Exposures stem from the widespread use of bulk materials including petroleum naphthas, gasoline and aliphatic and rubber solvents in various tire manufacturing operations.