Sex-specific differences in serum phosphate persist in patients with CKD.

INTRODUCTION

Phosphate plays a critical role in numerous metabolic processes, and sex-specific differences have been identified in its concentrations in the general population. However, such differences have not been investigated in the context of CKD, in which additional factors may exert a more pronounced impact on these levels.

METHODS

This retrospective study was conducted in an outpatient nephrology clinic and included data from 632 patients with CKD stages 1-5.

RESULTS

Serum phosphate was negatively associated with age (r = -0.08; p = 0.04) and estimated glomerular filtration rate (eGFR) (r = -0.23; p < 0.001). Women had significantly higher serum phosphate levels than men (3.6 mg/dL vs. 3.3 mg/dL; p = 0.01), an association confirmed in multivariate analysis. No significant sex differences were observed in serum calcium, parathyroid hormone (PTH), 25-hydroxyvitamin D, or the use of vitamin D supplements, calcium salts, or calcitriol.

CONCLUSION

Even in the presence of CKD, women have higher serum phosphate (P) levels than men. This sex difference should be considered in the management of CKD-mineral and bone disorder (CKD-MBD).