The Role of Trace Metals and Environmental Factors in the Onset and Progression of Schizophrenia in Pakistani Population


Exposure to toxic chemicals appears to be one of the major factors in the onset of Schizophrenia. Present study was designed to find out the association of socio-economic, clinical and heavy metals such as chromium (Cr), lead (Pb) copper (Cu), zinc (Zn), iron (Fe), manganese (Mn) selenium (Se) and arsenic (As) as the principle environmental factors that appear to impact schizophrenic condition in Pakistani population. In this study we have tried to expose some factors such as drug abuse, marital status, education, monthly income that could be related to the disease. These parameters were not investigated before in Pakistani subjects. A self-made questionnaire was developed to collect and record the history of patient’s social and economical status. The level of transition metals in the whole blood was also measured by using Inductive couple plasma optical emission spectroscopy (ICP-OES). Present study has found higher levels of Cr, Pb, Zn, Se, As and Cu and lower levels of Fe and Mn in the blood of newly diagnosed (ND) patients when compared to the controls. While comparing ND with the patients who were on medication (Old Diagnosed) we, found lower level of these metals except for copper in ND. However no significant differences were observed between any trace metal levels between the studied groups. The survey concludes that economic status, marital status and illegal drugs are significantly associated with schizophrenia. Pakistani men who use cannabis are significantly higher in numbers when compared to women in acquiring the psychiatric symptoms.

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Nawaz, R. , Zahir, E. , Siddiqui, S. , Usmani, A. and Shad, K. (2014) The Role of Trace Metals and Environmental Factors in the Onset and Progression of Schizophrenia in Pakistani Population. World Journal of Neuroscience, 4, 450-460. doi: 10.4236/wjns.2014.45051.

Conflicts of Interest

The authors declare no conflicts of interest.


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