Fibroid uterus cases with anemia in premenopausal women are more likely to have vitamin D deficiency as compared to cases without anemia, according to a study from India in the journal Cureus.
The hospital-based case-control study evaluated the association between serum ferritin and vitamin D levels.
The study was conducted in the Department of Biochemistry at All India Institute of Medical Sciences in Bhubaneswar, India.
In total, 60 clinically diagnosed premenopausal women with uterine fibroids (UFs), aged 25 to 45, who were attending the outpatient section of the hospital’s ob/gyn department were enrolled randomly: 30 women with anemia and 30 without anemia.
A peripheral blood smear, a complete blood count (CBC) and hemoglobin (Hb) were measured by a fully automated analyzer; serum ferritin levels were estimated by a three-site sandwich immunoassay using direct chemiluminometric technology in a chemiluminescence immunoassay analyzer; and 25(OH) vitamin D level was measured by an enzyme-linked immunosorbent assay (ELISA).
The 1-hour daily exposure to sunlight was moderate in all patients, thus eliminating the confounding effect of sunlight exposure influencing vitamin D levels.
In the anemic group, 28 patients had vitamin D deficiency and 2 were vitamin D insufficiency, compared to 19 patients in the control group who were vitamin D deficient, 9 with vitamin D insufficiency and 2 with vitamin D sufficiency.
A significant difference was found in ferritin levels between cases and control (P < 0.001). There was also a strong positive correlation between serum ferritin and vitamin D levels.
The median vitamin D level in cases was 5.0 ng/ml [interquartile range (IQR): 4.8], compared to 18.4 ng/ml (IQR: 7.9) in controls (P < 0.001).
In addition, 5 patients in the anemic group were found to have an iron deficiency state, all of whom had vitamin D deficiency.
The odds ratio with a 95% confidence interval (CI) between the serum vitamin D groups (vitamin D deficiency and vitamin D insufficiency) and serum ferritin groups (low and normal ferritin levels) was 9.6 (95% CI: 1.1 to 80.9 (P = .019).
“This indicates that low ferritin levels are associated with vitamin D deficiency in fibroid subjects,” wrote the authors.
Factors affecting vitamin D levels include female gender, winter season, lack of sunlight exposure, residence in high latitudes, dark skin, clothing with low exposure, obesity, low socioeconomic status, and malnutrition.
Serum ferritin and Hb levels were the 2 important factors impacting serum vitamin D values.
“Low serum vitamin D levels in fibroid cases could be due to the fact that vitamin D reduces the effect of transforming growth factor β3 (TGFβ3)-mediated expression of collagen type-1, and the expression and activity of metalloproteinase (MMP-2, MMP-9) that degrades the extracellular matrix,” wrote the authors.
The authors noted that vitamin D estimation in fibroid uterus cases with anemia would help better manage patients.
The strong positive correlation observed between serum ferritin and vitamin D levels indicates that fibroid uterus cases “with microcytic hypochromic anemia should also be evaluated for vitamin D deficiency, as timely corrective measures would improve the treatment outcomes in women with fibroid uterus,” concluded the authors.