The mean age of cases was 47.5th± 9.8 years and for the control group was 46.2th + 2.6 years. There were 46.7% premenopausal females and 53.3 % postmenopausal females among the breast cancer population. Age, marital status, menopausal, residential area, and parda observing status had almost similar distribution among cases and controls. A total of 70% of the cases were multiparous and the 50% of the healthy controls had more than three children. Regarding the occupational history, 92% of the cases were house wives while 33% of the controls were office workers. Seventy percent of the study population in both groups had BMI ≥25. Breast cancer females with BMI ≥30 were 28 versus 18 in the control group.
The mean serum vitamin D level in the breast cancer patient was 9.3 ng/ml and in the control group was 14.9 ng/ml and the P value calculated was <0.001. Vitamin D deficiency was seen in 95.6% (86) breast cancer patients while 77% (69) of the control group were deficient, the P value was <0.001. Suboptimal levels of vitamin D were seen in 4.4% (4) of the cases and 18.9% (17) control group, P value <0.001. None of the breast cancer patients had an optimal vitamin D level, while four patients in the control group had normal serum levels .
Serum vitamin D level in cases and controls
Among the breast cancer patients the tumor characteristics (histology, grade, stage, and receptor status) did not show any significant associations with serum levels of vitamin D.
On analysis of the individual grade of breast cancer with serum vitamin D levels, it was seen that grade III tumors had a mean vitamin D level of 8.6 ng/ml + SD 3.44, while similar low levels (mean 8.5 ng/ml + SD 3.54) were also seen in grade I tumors. Grade II breast cancer patients had a mean serum vitamin D level of 10.28 + SD 6.23. The P value calculated by Anova was 0.26.
Serum vitamin D levels were found to be lower (mean 8.49 ng/ml and 9.86 ng/ml) in stage III and IV breast cancer respectively and 12.75 ng/ml in stage I disease but the P value was 0.247 .
Association of serum vitamin D level with Stage of breast cancer
On comparing serum vitamin D levels with receptor status, patients with Her2neu over expression had a mean vitamin D level of 8.28 ng/ml + SD 2.3, patients with triple negative tumors had mean serum vitamin D levels 10.3 ng/ml + SD 4.65, triple positive and ER positive/Her2 negative had 9.04 ng/ml + SD 3.97 and 9.06 ng/ml + SD 5.5 respectively. The calculated P value was 0.681.
According to the menopausal state of breast cancer patients, premenopausal females had a mean serum vitamin D level of 10.5 ng/ml and postmenopausal females had a mean value of 13.5 ng/ml. The P value by t-test was 0.015 .
Distribution of serum vitamin D level according to menopausal status of breast cancer patients
On estimation of bone mineral density (BMD) in vitamin D deficient breast cancer patients, 36 patients had normal bone density, 34 patients had Osteopenia, and 16 patients had Osteoporosis. Four patients had suboptimal vitamin D levels, out of which 2 had osteopenia and 1 had normal bone density and Osteoporosis each. The P value by chi-square test was 0.787.
Low BMD (Osteopenia and Osteoprosis) among the postmenopausal breast cancer patients was found in 35/45 (73%) females while only 18/42 (43%) premenopausal females had low BMD (osteopenia only) with a P value of <0.001 .
Correlation of bone mineral density with menopausal state of breast cancer patients