Singapore study finds unvaccinated Covid-19 survivors face higher risk of heart complications

Unvaccinated people who have recovered from COVID-19 are at heightened risk of heart complications almost a year later, a national study led by NTU and affiliated faculty has found.

The study, based on testing and medical claims records of 106,012 people resident in Singapore and diagnosed with COVID-19 between 1 September and 31 November 2021, was during the period of the Delta variant predominance. The study found that many (912 patients) who have recovered from COVID-19 have reported lingering after-effects, consistent with the ‘long Covid’ syndrome. These may include symptoms of fatigue, shortness of breath, problems with memory, and heart complications like cardiovascular, cerebrovascular and thrombosis. 

This COVID-19 positive group was compared with a group of nearly 1.7 million in the community who were not known to be infected with the virus during that time. Both groups were tracked over an average period of 300 days, looking at whether they developed ‘long Covid’ syndrome and, specifically, heart complications.

The study, published in Clinical Infectious Diseases in September, is the first and largest to examine the risk of long COVID-19 in a highly vaccinated, multi-ethnic Southeast Asian population.

The study was carried out by researchers from NTU’s LKCMedicine, Ministry of Health, Singapore, Singapore General Hospital, and National Centre for Infectious Diseases, Singapore.