<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Background </span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Most patients infected with COVID-19 experienced cold-like symptoms. Some other patients developed more serious symptoms such as pneumonia. N-Acetylcysteine (NAC) is known to be effective against acute respiratory distress syndrome (ARDS) due to its anti-inflammatory and antioxidant properties. The effect of NAC on hospitalized COVID-19 patients was unknown. Therefore, this meta-analysis aimed to establish a relationship between the effects of NAC and non-NAC protocols in inpatients with COVID-19. </span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Method</span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">By March 2022, a systemic review was conducted to assess the effects of NAC and non-NAC in inpatients with COVID-19. The clinical trials were identified in 20553 subjects admitted with COVID-19 at baseline. 2909 was treated with NAC and 17644 was treated without NAC. This study attempts to compare the effects of NAC and non-NAC in COVID-19 patients hospitalized with pneumonia. Statistical analysis uses the dichotomous method as a tool for odds ratio (OR) at<span style="mso-spacerun: yes;"> </span>95% confidence interval (CI) to assess the effectiveness of NAC and non-NAC in COVID-19 patients hospitalized with pneumonia in random or fixed-effect model.</span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Results </span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Patients managed with NAC had fewer days in the ICU </span><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-fareast-font-family: 'Times New Roman'; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; color: #0e101a;">(OR, 2.79; 95% CI, -1.11-6.69, <em>p </em>= 0.16), </span><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">lower mortality (</span><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-fareast-font-family: 'Times New Roman'; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; color: #0e101a;">OR, 0.69; 95% CI, 0.40-1.20, <em>p </em>= 0.19), and fewer number needed mechanical ventilation (OR, 0.74; 95% CI, 0.25-2.21, <em>p </em>= 0.59) compared with non-NAC in COVID-19 subjects hospitalized with pneumonia.</span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">Conclusion </span></p>
<p class="MsoNormal" style="margin-bottom: .0001pt; text-align: justify; line-height: normal;"><span style="font-size: 10.0pt; font-family: 'Arial',sans-serif; mso-ascii-theme-font: minor-bidi; mso-hansi-theme-font: minor-bidi; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi;">NAC has decreased the days stayed in the ICU, number of deaths, and number of patients needed mechanical ventilation in COVID-19 hospitalized with pneumonia, although, this difference was insignificant. Further studies are required that could affect the level of significance.</span></p>