ABSTRACT
BACKGROUND: Regular use of aspirin has been associated with a reduced risk of cancer at several sites but the data for endometrial cancer are conflicting. Evidence regarding use of other analgesics is limited. PATIENTS AND METHODS: We pooled individual-level data from seven cohort and five case-control studies participating in the Epidemiology of Endometrial Cancer Consortium including 7120 women with endometrial cancer and 16 069 controls. For overall analyses, study-specific odds ratios (ORs) and 95% confidence intervals (CI) were estimated using logistic regression and combined using random-effects meta-analysis; for stratified analyses, we used mixed-effects logistic regression with study as a random effect. RESULTS: At least weekly use of aspirin and non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with an approximately 15% reduced risk of endometrial cancer among both overweight and obese women (OR = 0.86 [95% CI 0.76-0.98] and 0.86 [95% CI 0.76-0.97], respectively, for aspirin; 0.87 [95% CI 0.76-1.00] and 0.84 [0.74-0.96], respectively, for non-aspirin NSAIDs). There was no association among women of normal weight (body mass index < 25 kg/m2, Pheterogeneity = 0.04 for aspirin, Pheterogeneity = 0.003 for NSAIDs). Among overweight and obese women, the inverse association with aspirin was stronger for use 2-6 times/week (OR = 0.81, 95% CI 0.68-0.96) than for daily use (0.91, 0.80-1.03), possibly because a high proportion of daily users use low-dose formulations. There was no clear association with use of acetaminophen. CONCLUSION: Our pooled analysis provides further evidence that use of standard-dose aspirin or other NSAIDs may reduce risk of endometrial cancer among overweight and obese women.
Subject(s)
Acetaminophen/adverse effects , Analgesics, Non-Narcotic/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Aspirin/adverse effects , Endometrial Neoplasms/epidemiology , Case-Control Studies , Cohort Studies , Endometrial Neoplasms/chemically induced , Female , Follow-Up Studies , Humans , Prognosis , Risk Factors , United States/epidemiologyABSTRACT
BACKGROUND: This is the first prospective cohort analysis on the association between vitamin D and endometrial cancer incorporating time-varying predicted plasma 25-hydroxyvitamin D [25(OH)D]. METHODS: The prospective cohort analysis of predicted 25(OH)D and total dietary vitamin D intake used the Cox proportional hazards model, and involved 644 incident endometrial cancer events from 1986 to 2006 in the Nurses' Health Study. Genotyping and unconditional logistic regression were carried out on 572 endometrial cancer cases and their matched controls on 12 single nucleotide polymorphisms (SNPs) in vitamin D-related genes. RESULTS: There was no significant association between predicted 25(OH)D and endometrial cancer incidence, with the hazard ratio for the highest (versus the lowest) quintile of predicted 25(OH)D as 1.00 (95% CI 0.73-1.36) (p-trend = 0.33). There was also no significant association involving total dietary vitamin D. No significant associations between any of the vitamin D-related SNPs and endometrial cancer were observed. CONCLUSION: Both predicted 25(OH)D and total dietary vitamin D intake were not associated with endometrial cancer incidence. These results suggest that vitamin D may not protect against the development of endometrial cancer. However, the low and narrow vitamin D exposure range in the cohort may limit generalizability of the results.
