Background: Despite the emerging literature supporting the beneficial role of sufficient vitamin D level and its association with various cancers, current evidence on the vitamin D and the risk of getting breast cancer is still inconsistent. Furthermore, the study between vitamin D status and breast cancer risk among south east Asian women is limited. Aim: We aimed to investigate the association between vitamin D deficiency and the risk of getting breast cancer among Malaysian women. Methods: We conducted a retrospective nested case control study which consisted of Malaysian Breast Cancer Cohort Study (MyBCC) subjects as the cases and UMMC Mammogram Cohort Study subjects as the hospital control. We also used a secondary data from the Cohort Study on Clustering of Lifestyle Risk Factors and understanding its association with stress on health and well-being among school teachers in Malaysia (CLUSTer), as we only included the data from the schools in Kuala Lumpur as the population control. We measured and compared serum 25-hydroxyvitamin D (25(OH)D) between newly diagnosed breast cancer patients (n= 231), female without cancer who came for mammogram checkup (n= 462) and female teachers without cancer from schools in Kuala Lumpur (n=231). Vitamin D deficiency was defined as serum (25(OH)D) < 50 nmol/L. Results: Median serum (25(OH)D) for cases and controls were 42.43 nmol/L and 44.30 nmol/L, respectively. We examined the association between serum (25(OH)D) and breast cancer risk stratified by age < 50 and ≥ 50 years old. The crude ORs for breast cancer risk in cases and controls did not show statistically significant association with serum (25(OH)D) for both age groups ( P = 0.463 and P = 0.650, respectively). After adjustment for age, ethnicity, education level and BMI the ORs (95% CI) for breast cancer risk among both groups were 1.183 (0.591-2.366) ( P = 0.635) and 1.237 (0.801-1.911) ( P = 0.338) respectively for women with serum (25(OH)D) < 50 nmol/L. Conclusion: Our results suggest that there is lack of association between vitamin D deficiency and the risk of getting breast cancer in Malaysian women.
Roles of Kermanshahi Oil, Animal Fat, Dietary and Non-Dietary Vitamin D and other Nutrients in Increased Risk of Premenopausal Breast Cancer: A Case Control Study in Kermanshah, Iran
