Correlation of serum levels of Vitamin D(3) with serum parathormone in nursing mothers and infants 1-6 months’ age from South Punjab, Pakistan

BACKGROUND AND OBJECTIVE: Parathormone (PTH) and serum Vitamin D(3) (VD(3)) share a complex interplay where increased VD(3) leads to a negative response on parathormone level. Our objective was to determine the correlation of parathormone (PTH) and Vitamin D(3) (VD(3)) levels in nursing mothers and infants 1-6 months’ age from South Punjab, Pakistan. METHODS: This study is a secondary data analysis of previously conducted cross sectional study which was conducted at the Department of Pediatric Medicine, Nishtar Medical University, Multan, during August 2010 to June 2011. Study included 67 infants 1-6 months of age and 60 nursing mothers. A venous blood sample was drawn for estimation of VD(3), calcium, phosphate, alkaline phosphatase, parathormone and albumin. Spearman correlation coefficient was calculated to determine the inverse correlation between PTH and VD(3) levels. RESULTS: Mean age (in days) of the infants was 83±53.7 days whereas maternal mean age was 25.53 ± 4.12 years. Median VD(3) level in infants was 20.90 ng/ml (IQR – 49.5). Median serum PTH levels were 20.90 pg/ml (IQR – 26.17). Median VD(3) level in nursing mothers was 21.0 ng/ml (IQR 7.2– 43.8). Median maternal serum PTH levels were 20.89 pg/ml (IQR 2.9 – 232.4). Substantial negative relation between VD(3) and parathormone in infants and mothers was not evident (r = - 0.027, p-value 0.83) and (r = 0.156, p-value 0.23) respectively. A significant positive association between infant and maternal VD(3) was observed (r(s) –0.55, p-value < 0.001). CONCLUSION: Our study affirms that the customary negative correlation between VD(3) and parathormone levels does not exist.