PAJANAN PESTISIDA SEBAGAI FAKTOR RISIKO DISFUNGSI TIROID PADA KELOMPOK WANITA USIA SUBUR DI DAERAH PERTANIAN DATARAN RENDAH

Abstract

Background Thyroid disfunction (hypothyroidism) in women at childbearing age (WCA) can cause reproduction disorder, i.e. infertility, spontaneous abortion, impaired growth and development of foetus, placental abruption, and preterm delivery. Pesticide exposure is suspected to cause thyroid dysfunction. The research objective is to prove that pesticide exposure is a risk factor for thyroid dysfunction among WCA in lowland agricultural areas. Research Methods This was an observational study, combined of cross-sectional and case-control design. Study subjects in cross-sectional study were 216 WCA and in case-control study were 44 WCA as cases and 45 WCA as controls. Pesticide exposure was measured by asking WCA’s involvement in agricultural activities using structured questionnaire and by checking their levels of cholinesterase. Thyroid dysfunction was determined based on the results of TSH, FT4, and T3 level. Confounding variables were also measured. These variables were age, BMI, haemoglobin level, participation in hormonal contraception, liver function, iodine intake, intake of goitrogenic substances, blood lead level, exposure to cigarette smoke, habit of using insect repellent and habit of using plastic for food packaging. Chi-square test, OR (95% CI), and multivariate logistic regression were implemented to test the hypothesis. Results The prevalence of hypothyroidism among WCA was 22.2% and of hyperthyroidism was 2.3%. There was no significant difference in the proportion of miscarriage and gave birth to low birth weight history between case and control group (p-value > 0.05), but the proportion is higher in the case group than control. Onion harvest activities (OR = 2.7) and removing onions from the stalks (OR = 3.3) are risk factors for thyroid dysfunction. Exposure to pesticides is a risk factor for thyroid dysfunction (hypothyroidism) (adjusted OR = 3.31, 95% CI = 1.25 to 8.78, p = 0.016). The higher the degree of exposure, the greater the risk of having thyroid dysfunction. Based on the data and the theory analysis, the pathogenesis of hypothyroidism was suspected through the disruption of TPO function, D1 enzyme inhibition and D3 enzyme activation. Conclusion Exposure to pesticides is a risk factor for thyroid dysfunction among WCA in lowland agricultural areas. The pathogenesis of hypothyroidism was suspected through the disruption of TPO function, D1 enzyme inhibition and D3 enzyme activation. Key words: pesticide exposure, thyroid dysfunction, hypothyroidism, lowland agricultural area, women at childbearing age