Factors Associated with Thyroid Dysfunction in Hypothyroidism-Endemic Region of Ravansar, 2017-2018: A Cross-Sectional Analysis

   Background & Objective: Hypothyroidism is a prevalent condition in various regions all over the world, including Iran. This study aimed to identify the factors associated with thyroid dysfunctions in Ravansar area, Kermanshah province. Due to hypo and hyperthyroidism diversity and pathogeneses complexity, machine learning was also integrated; it is as an accurate and potent method for the dimensionality reduction to realize the study objective.  Materials & Methods: In this study, 10069 individuals participated from Ravansar area. Data were taken from the Ravansar Non-Communicable Diseases (RaNCD) cohort study, which is a part of national PERSIAN cohort. Feature selection was done using random forests machine learning tool. The two thyroid diseases correlation was explored through conventional statistical procedures.  Results:  Female sex was the most significant risk factor for hypothyroidism (OR=6.24, CI: 4.13-9.63; P<0.001). Depression (OR=2.07, CI: 1.34-3.09; P<0.001), age group of 45-55 years (OR=1.56, CI: 1.18-2.07; P<0.01), daily salt consumption of >10 gr (OR=1.87, CI: 1.15-2.90; P<0.01), kidney stone (OR=1.35, CI: 1.02-1.78; P<0.05) and unsaturated fats intake (OR=1.01, CI: 1.00-1.02; P<0.05) were significantly associated with underactive thyroid condition. No significant associated factor was found for hyperthyroidism.  Conclusion:  Female sex is a global well-established hypothyroidism-associated factor. The results of the present study suggest taking some measures to reduce hypothyroidism, by addressing the intervening factors.