Environmental Exposure to Lead and Its Health Effects on Patients With Maintenance Hemodialysis

Study Overview
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Brief Summary
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One thousand patients with LHD who have no history of exposure to lead will be observed for 18 months. Blood lead level(BLL), biochemical data, hemoglobin, albumin, Cr, high sensitivity C-reactive protein (HsCRP), and blood cell counts are assessed at baseline. The morbidity and mortality are recorded in detail. Then, one hundred subjects with high BLL (>20μg/dl) will be randomly assigned to the study and control groups. For 3-6 months, the 50 patients in the study group will receive lead-chelation therapy with calcium disodium EDTA weekly until the BLB falls below BLL< 5 μg/dl, and the 50 control group patients receive weekly placebo for 12 weeks. During the ensuing 18 months, the BLL, biochemical data will be regularly followed up every 3 months. BLL is measured every 6 months. If BLL of the study group patients increase >10 μg/dl, the chelation therapy will be performed again until their BLL is <5 μg/dl. The primary end point is morbidity or mortality during the observation and follow-up period. A secondary end point is the change in hemoglobin, albumin, Cr and Hs CRP during the follow up period.

Conditions
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Anemia, Malnutrition, Inflammation, Lead Poisoning

Intervention / Treatment
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* Drug: lead chelation therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: MHD patients have dialyzed for more than 6 months and age >18 and < 90 year-old Exclusion Criteria: Patients with malignancies and obvious infectious diseases as well as those who are hospitalized or underwent surgery or renal transplantation within the 3 months preceding the investigation;Patients with a history of occupational exposure to heavy metals, metal intoxication, living in metal-contaminated areas were also excluded.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: lead chelation therapy|Patients with lead poisoning (BLL> 20μg/dl) are randomly assigned to a control or chelation group, on the 1:1 proportion. During the 3 months, 50 chelation group patients receive 2-hour weekly intravenous infusions of one vial (1 g) of calcium di-sodium EDTA mixed with 200 ml of normal saline until BLB is BLL < 5 μg/dl. Fifty control patients receive weekly 2-hour infusions of one vial (20 ml) of 50% glucose mixed with 200 ml of normal saline over a period of 12 weeks9.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The primary end point is morbidity or mortality during the follow-up period. |  | 18 months follow-up period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A secondary end point is the change in HB, albumin, Cr and Hs CRP during the follow up period. |  | 18 months follow-up period | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Environmental lead exposure, maintenance hemodialysis; blood lead levels, EDTA chelating agents, malnutrition, anemia, inflammation, mortality., To determine whether lead chelation therapy improves the anemia, malnutrition, inflammation, morbidity or mortality in hemodialysis patients.