Pesticides and Chemicals As Potential Risk Factors of Aplastic Anemia: A Case-Control Study Among a Pakistani Population

Introduction: Aplastic anemia is a rare and potentially life-threatening hematological disorder with incidence of 1.4 to 14 cases/million. It is associated with exposures to certain environmental chemicals, drugs and infections. The objective was to investigate the association of illness with family history of aplastic anemia, exposure to pesticides and chemicals.

Methodology: A hospital-based case-control study (191 cases, 696 controls) was conducted from 1st January 2015 to 31st December 2018 in Karachi, Sindh. Cases were patients with diagnosis of aplastic anemia confirmed with bone marrow biopsy. Controls neither had aplastic anemia nor other hematological chronic diseases. An in-person interview was conducted to collect demographic information, family history of aplastic anemia, and history of pesticide and chemical exposure. The adjusted odds ratios (aOR) with 95% confidence intervals (CI) were estimated via SPSS v22.

Results: A total of 191 confirmed aplastic anemia cases were selected. Mean age was 29 years (range: 4-69) and predominantly there were males 129 (67.5%). The majority, 84 (44.0%), of the cases were aged 16-30 years. In multivariate analysis models, the significant associations were observed between aplastic anemia with family history of aplastic anemia (aOR=13.3, 95% C.I 3.66-48.50), exposure to pesticides (aOR=2.1, 95% C.I 1.23-3.61) and chemicals (aOR=3.6, 95% C.I 2.06-6.34).

Conclusion: This study observed a significant association of aplastic anemia with family history of aplastic anemia, exposure to pesticide and insecticide exposure. However, to establish this connection, further longitudinal studies are warranted.