en Infectious Diseases Infectious Diseases Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:14pt"><b><i><span style="color:blue">Background:</span></i></b><b> </b>COVID-19 has multiple effects on the endocrine system, particularly altering the levels of growth hormone (GH), insulin-like growth factor-1 (IGF-1), and cortisol, which may influence disease severity and prognosis. This study aimed to evaluate circulating levels of GH, IGF-1, and cortisol in COVID-19 patients categorized by disease severity, including outpatients, inpatients, and intensive care unit (ICU) patients.</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Methods:</span></i></b> A total of 118 confirmed COVID-19 patients were divided into three groups: outpatients, inpatients, and ICU patients. Serum levels of GH, IGF-1, and cortisol were measured using ELISA and statistically compared across groups. Correlations among these hormones were also analyzed.</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Results:</span></i></b> Cortisol levels were highest in inpatients, intermediate in ICU patients, and lowest in outpatients. GH levels were reduced in ICU patients compared to other groups, with no difference between inpatients and outpatients. IGF-1 levels were highest in outpatients, followed by inpatients, and lowest in ICU patients. A significant inverse correlation between cortisol and IGF-1 was observed only in ICU patients (p = 0.013).</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Conclusion:</span></i></b> COVID-19 severity is associated with dysregulation of GH, IGF-1, and cortisol. The inverse cortisol&ndash;IGF-1 correlation in ICU patients suggests the impact of physiological stress on hormonal imbalance and impaired recovery. Endocrine interventions may improve clinical outcomes in severe cases.</span></span></span> COVID-19, Growth hormone (GH), Insulin-like growth factor-1 (IGF-1), Cortisol, Disease severity 671 677 http://caspjim.com/browse.php?a_code=A-10-3877-1&slc_lang=en&sid=1 Mohammad Hosseinzadeh hosseinzadeh.1376@yahoo.com 100319475328460057948 100319475328460057948 No Department of Biochemistry and Genetics, School of Medical Sciences, Arak University of Medical Sciences, Arak, Iran. Mohammad milad Shirvandehi miladshirvandehi@gmail.com 100319475328460057949 100319475328460057949 No Department of Microbiology, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran. Navid Sehat Navid.sehat@gmail.com 100319475328460057950 0009-0003-3710-9392 No Department of Internal Medicine, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran. Azam Moslemi moslemiazam@gmail.com 100319475328460057951 100319475328460057951 No Department of biostatistics, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran. Ehsanollah Ghaznavi-Rad ghaznaviehs@yahoo.com 100319475328460057952 100319475328460057952 No Infectious Diseases Research Center, Arak University of Medical Sciences, Arak, Iran. Behzad Khansarinejad Khansarinejad@gmail.com 100319475328460057953 100319475328460057953 No Department of Microbiology, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran. Hossein Sarmadian hsarmadian2015@gmail.com 100319475328460057954 100319475328460057954 No Infectious Diseases Research Center, Arak University of Medical Sciences, Arak, Iran. Mohammad Rezvanfar rezvanfar@gmail.com 100319475328460057955 100319475328460057955 No Department of Internal Medicine, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran. Farideh Jalali Mashayekhi mashayekhif@yahoo.com 100319475328460057956 100319475328460057956 Yes Department of Biochemistry and Genetics, School of Medical Sciences, Arak University of Medical Sciences, Arak, I.R. Iran.