Blood lead as a risk factor for myocardial infarction in Universiti Kebangsaan Malaysia Medical Center

Abstract

Lead is one of the pollutants that can cause adverse effects on human health. The exposure of lead has received much attention in some decade due to its non biodegradable properties. Blood lead measurement is the most convenient as well as the most feasible to indicate lead toxicity. The aim of this study was to assess the association between blood lead and myocardial infarction (MI). This is a hospital-based case-control study and was conducted at Universiti Kebangsaan Malaysia Medical Center. The case-control study enrolled 109 respondents; 71 cases and 38 non-cases of myocardial infarction. Research instruments include questionnaires on demographic factors (age, gender, and ethnicity), socioeconomic (education, household income, occupation), lifestyle (smoking, and alcohol consumption), body mass index (BMI), premorbid history, family history, and blood level measurement using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). None of the respondents from cases and control group have blood lead concentrations of more than 10μg/dL. Median and standard deviation of the blood lead level for case and control groups were 3.72 ± 5.46μg/dL and 2.81 ± 2.14μg/dL respectively. However, there was not a significant difference of the blood lead level between cases and control groups (Z = -1.48; p>0. 05). The relationship test showed that there was a significant relationship between blood lead concentration of 5 µg/dL and MI. (χ2 = 4.397, p = 0.03). In conclusion, this study has shown that there is a relationship between blood lead levels and MI. The blood lead level of cases is higher than non-cases, but still under the level of 10 μg/dL. This study concluded that the presence of lead in the blood is one of the factors that contribute to MI even at the lower concentration. The findings of this study are very important and provide new information regarding lead and myocardial infarction risk.