Blood Lead Levels, Malnutrition, Inflammation, and Mortality in Patients With Diabetes Treated by Long-Term Hemodialysis

Abstract

Blood lead levels (BLLs) are associated with mortality in the general population. The clinical significance of BLLs in long-term hemodialysis (HD) patients with diabetes is unknown. A cross-sectional and 1-year prospective study. 211 patients with diabetes on long-term HD therapy at 3 centers. BLLs measured before HD at baseline, categorized as abnormal (>20 microg/dL), high normal (10 to 20 microg/dL), and low normal (<10 microg/dL). Malnutrition, defined as serum albumin level less than 3.6 g/dL, and inflammation, defined as high-sensitivity C-reactive protein level greater than 3 mg/dL, for cross-sectional analyses. Mortality and cause of death for longitudinal analyses. 34, 112, and 65 patients had abnormal, high-normal, and low-normal BLLs at baseline. At baseline, patients with abnormal BLLs had a greater proportion of malnutrition (14.7% versus 1.5% and 11.6%; P = 0.01) and inflammation (76.5% versus 52.3% and 50.9%; P = 0.01) than those with low- and high-normal BLLs. Backward stepwise regression analysis found that high-sensitivity C-reactive protein level correlated positively and albumin level correlated negatively with BLLs after other confounders were adjusted. At the end of follow-up, 16 patients had died. Kaplan-Meier analysis showed that patients with an abnormal BLL had greater mortality than those with low and low-normal BLLs (P = 0.004). Small sample size, sparse outcomes, and limited follow-up. BLL may contribute to inflammation and nutritional status in long-term HD patients with diabetes on long-term HD therapy and may relate to 1-year mortality in these patients.