Risk of Acute Lymphoblastic Leukemia: Results of a Case-Control Study

Abstract

Background: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Different<br />environmental factors might be effective in the occurrence of this malignancy during childhood. The aim of this study<br />was to find environmental risk factors in childhood ALL in Hamadan, Iran. Methods: This case-control study was<br />done in 2015-2018 on 125 children younger than 15 years of age suffering from ALL. Patients were matched with<br />130 controls with respect to age, gender, and residence location. The identification of risk factors for ALL was sought<br />based on the comparison of studied variables between case and control individuals. Results: A statistically significant<br />increased risk for ALL was found with regard to type of delivery (OR: 0.43, 95% CI: 0.20 - 0.92, p˂0.02), childcare<br />(OR: 4.58, 95% CI: 0.95 - 22.20, p˂0.04), birth weight (OR: 1.44, 95% CI: 1.53 - 2.21, p˂0.006), father's education<br />level (OR: 2.67, 95% CI: 1.10 - 6.45, p˂0.02), and father's job (OR: 0.2 95% CI: 0.08 - 0.51, p˂0.001). Also observed<br />were increased odds for ALL regarding male gender, mother's high education level, mother's freelance job, and medium<br />or high family income. No association with ALL incidence was observed for age, gender, breastfeeding, mother's age<br />at pregnancy, malignancy in first- or second-degree relatives, or mother's use of hair dye during pregnancy (p> 0.05).<br />Conclusion: This study showed that father's education level, father's job, delivery type, birth weight, and childcare<br />can play a role in the incidence of childhood ALL.