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Show Figure 1. Kaplan-Meier Prostate-Cancer Specific Survival Probability Estimates by LDS Status. 0.95-------------------- 12 16 20 24 28 32 36 40 44 48 52 56 60 64 72 76 80 84 88 92 96 100 104 108 112 116 120 124 128 132 136 140 144 148 152 156 160 164 . Survival Time in M onths + Religiously Active LDS a Religiously Less Active LDS - Non-LDS A proportional hazards model was used to estimate the death hazard for prostate cancer among prostate cancer cases diagnosed from 1985 through 1999, with religiously active LDS as the referent group. The death hazard for less religiously active LDS was 1.32 (95% CI: 1.17 - 1.50) and for non-LDS 1.15 (95% CI: 1.01 - 1.30). The hazards model was then calculated adjusting for the following variables: age at diagnosis, race, marital status, summary stage, histologic grade, radiation therapy, surgery, and year of diagnosis (Table 2). The death hazard for less religiously active LDS was then 1.28 (95% CI: 1.13 - 1.45) and for non-LDS 1.00 (0.87 - 1.14). Each variable significantly contributed to the fit of the model except age and race. Finally, interaction terms between LDS status and the other variables in the model were sequentially added, but none were statistically significant and were subsequently dropped. DISCUSSION Prostate cancer-specific survival estimates, based on both the Kaplan-Meier and unadjusted Cox proportional hazards methods, were significantly lower for religiously less active LDS and non-LDS compared with religiously active LDS in Utah. The adjusted Cox proportional hazards models explained the difference in survival between religiously active LDS and non-LDS and some, but not all, of the difference in survival between religiously active LDS and religiously less active LDS. Specifically, religiously active LDS are more likely to experience the favorable effects on prostate cancer survival of being married, not having distant-staged disease, and being more likely to be treated with radical prostatectomy.235689 Doctrine and practices of the LDS Church may promote better survival through these causal pathways. Better survival among married men with prostate cancer may be attributed to forces that promote good health and also encourage marriage (i.e., healthier men select marriage). Alternatively, it may be that marriage encourages a lifestyle, including better access and quality of health care, better health habits, and provides a social support system that results in better health and life expectancy. The LDS Church advocates marriage and family.24 This may explain the comparatively high level of mar- ried men observed in this study. Perhaps married men with prostate cancer survive better than non-married men with the disease because marriage provides a large part of their social needs. Althougli the social needs satisfied through marriage may result in better survival among prostate cancer cases, the mechanism by which this is done is not fully understood. Perhaps by satisfying certain social needs, stress is reduced, which improves the body's hormonal balance and immune system, which in turn helps fight cancer. Although adjustment for several selected factors was sufficient to explain the difference in disease-specific survival between religiously active LDS and non-LDS, these factors were insufficient to explain the difference between religiously active LDS and religiously less active LDS. Religiously less active LDS prostate cancer cases continued to have a higlier hazard of death from prostate cancer. Our data did not include lifestyle information. However, it is well established that religiously active LDS are less likely to smoke cigarettes. Based on the 1996 Utah Health Status Survey, prevalence of current smoking in Utah was 0.4% for religiously active LDS, 21.4% for religiously less active LDS, 8.3% for religiously active non-LDS, 28.1% for religiously less active non-LDS, and 28.1% for individuals with no religious preference.25 LDS doctrine proscribes the use of tobacco, and consumption of alcohol, coffee and tea. and advocates a healthy diet among its members.26 Although abstention from cigarette smoking has not been associated with prostate cancer risk,27 it has been related to prostate cancer survival.10"1' Studies have previously examined the association between cigarette smoking and survival among prostate cancer cases. In a large study, higher death rates from prostate cancer were found in current cigarette smokers.10 hi another study involving 25,436 cancer cases from Memorial Sloan-Kettering Cancer Center's tumor registry, patients with a history of cigarette smoking, after adjusting for age, race, alcohol use, and histologic grade, had a poorer survival than nonsmokers.1' Statistically significant effects of smoking on survival were found in cases with oral, pancreatic, breast, and prostate cancer. Previous research has indicated that smoking may produce poorer survival by elevating levels of two steroids (serum testosterone and androstenedione), which may promote 16 Utah's Health: An Annual Review Volume LX |