Serum vitamin D levels and influencing factors in elderly patients with stage 3 to 4 chronic kidney disease / 中华老年医学杂志

ABSTRACT

Objective To investigate serum vitamin D levels and influencing factors in elderly patients with stage 3 to 4 chronic kidney disease (CKD) and to analyze the relationship between vitamin D deficiency and left ventricular hypertrophy (LVH).Methods This study involved 107 elderly outpatients (≥60 years) with stage 3 to 4 CKD who had visited Beijing Hospital between January 2014 and September 2016.We retrospectively analyzed their clinical and laboratory data including gender,age,height,weight,blood pressure,glycosylated hemoglobin,hemoglobin (Hb),albumin,creatinine,lipid,calcium,phosphorus,intact parathyroid hormone (iPTH),high sensitivity C-reactive protein,B-type natriuretic peptide (BNP),25-OH-D3,and ultrasonic cardiogram.Based on estimated glomerular filtration rate,patients were divided into three groupsthe stage 3a CKD group,the stage 3b CKD group,and the stage 4 CKD group.Differences in the parameters between the groups were compared.In addition,25-OH-D3 levels were used to determine whether the patient had vitamin D deficiency and the left ventricular mass index was used to identify left ventricular hypertrophy (LVH),and the relationship between vitamin D deficiency and LVH was examined.Results Body mass index,body surface area and calcium levels declined while age,phosphorus and BNP levels increased with the development of stage 3a,stage 3b and stage 4 CKD.Mean 25 O)H-D3 levels were 22.6 (5.9-58.0) μg/L and 17.5 (10.1 46.3) μg/L for CKD stage 3 and 4 patients,respectively,and the difference between them was statistically significant (Z =-2.121,P 0.033).Compared with patients with no vitamin D deficiency,patients with vitamin D deficiency were more likely to be female (x2 7.460,P=0.006) and were associated with higher P (Z=-2.090,P=0.037),iPTH (Z=-2.855,P=0.004) and BNP (Z=-3.134,P 0.002),and lower Hb (t=-3.305,P=0.001).The rates of LVH in vitamin D deficient patients and non-vitamin D deficient patients were 8 cases(34.8 ％) and 12 cases(14.3 ％),respectively (P=0.035).Conclusions Vitamin D levels show progressive decline as chronic kidney disease advances into later stages.In addition,vitamin D deficiency is more common among female patients and is often accompanied by lower Hb levels,higher BNP levels and higher incidences of calcium-phosphate metabolism disorders and LVH.The results suggest that vitamin D may play an important role in renal anemia,calcium-phosphate metabolism and LVH.