Left Ventricular Echocardiographic Variables in Occupational Exposure to Lead

Document Type : Original Article (s)

Authors

1 Associate Professor, Cardiac Rehabilitation Research Center, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran

2 Cardiologist, Department of Cardiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

3 Associate Professor, Isfahan Cardiovascular Research Center, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran

4 PhD Candidate, Isfahan Cardiovascular Research Center, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran

5 Isfahan Cardiovascular Research Center, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Lead contamination affects various body organs such as heart. This study was designed to assess the effects of lead on cardiac function in terms of echocardiographic indices among battery factory workers who are in constant exposure to lead.Methods: In a cross-sectional study, 142 male battery factory workers who had been exposed to lead for at least 1 year were evaluated. The subjects aged 25-55 years and were excluded if they had hypertension, diabetes, or cardiovascular diseases. Demographic characteristics, professional profile, lead exposure, history of respiratory diseases, drugs intake, height, weight and blood pressure and lifestyle information of the participants were recorded. Blood lead levels were measured through blood tests. M-mode and doppler echocardiography was finally performed over each subject. Linear regression analysis was used to analyze the data.Findings: The mean age of the subjects was 41.78 ± 13.58 years and the mean duration of lead exposure was 23.54 ± 14.44 years. The mean blood lead level was 7.59 ± 2.75 µg/dl. Left ventricular hypertrophy was detected in 12% of the participants. Blood lead levels were not significantly related with echocardiographic indices in the crude model or after adjustments for age alone or for age and other risk factors.Conclusion: Blood lead levels of our subjects were below standard values. Accordingly, no significant relation was found between left ventricular function indices and blood lead levels. However, lack of such relations could be caused by exclusion of individuals with hypertension or cardiovascular diseases. Structural modifications in battery factories following legislations in Iran might have been responsible for low blood lead levels among the subjects.

Keywords


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