Fasting has been shown to have an impact body systems in different manners. The influence of fasting on immune system regulation remains controversial. Immunomodulatory effect of nicotine was suggested recently. Low prevalence of smoking was observed among patients with COVID-19.
To study fasting as an immune modulator in relation to the severity and mortality of COVID-19 patients, and to determine the effect of smoking on such patients.
This is a comparative study included all PCR-confirmed COVID-19 patients during April, May and June 2020 in Basrah. The severity of and mortality due to COVID-19 infection were studied in fasting patients in Ramadan as compared with the non-fasting months before and one month later. Current smoking in relation to the severity of infection was also studied.
Significantly less severe cases and lower mortality were detected in patients with COVID-19 who were fasting as compared with non-fasting patients before and after the fasting month. Current smoking is significantly less frequently detected among severe as compared with mild to moderate cases.
Conclusion Fasting could be useful to improve immune response against infection and to reduce severity and mortality in patients with infections. Smoking benefit in preventing and ameliorating of respiratory tract infection needs to be further investigated.