Comparison of Serum Lead and Cadmium Levels in Parkinson's Patients and Healthy Controls

Background: Several studies have investigated the association of heavy metals such as lead and cadmium with neurodegenerative diseases such as Parkinson's disease. Objectives: In this study, we investigated the relationship between the serum levels of lead and cadmium in Parkinson's disease. Methods: In this case-control study, the serum levels of lead and cadmium in 100 patients with Parkinson's disease referred to our university hospital, and 30 healthy individuals were investigated. Basic information such as age and gender and other demographic and clinical data were registered in the checklist. The levels of lead and cadmium were measured using atomic absorption spectrophotometry (AAS). Data was analyzed by SPSS software version 23, and a P < 0.05 was considered as significant. Results: The mean cadmium level in patient and control groups was 14.91 +/- 8.72 and 4.71 +/- 2.72 ppb, respectively (P < 0.001). The mean lead level was 158.35 +/- 157.64 and 35.35 +/- 16.25 ppb in patients and controls, respectively (P < 0.001). At ages above 65 years, there was a significant difference between the level of cadmium (P < 0.001) and lead (P < 0.001) in patients and healthy subjects. In addition, there was a significant difference in the level of cadmium (P = 0.003) between patients and healthy subjects at ages below 65 years. This was true for both males (P < 0.05) and females (P < 0.05). There was no significant difference in the level of lead and cadmium in various severity rates of the disease, as well as in different symptoms of the patients. Conclusions: Based on the findings, the levels of serum lead and cadmium were higher in the patients, indicating a probable relationship between the Parkinson's disease and the levels of these metals.