Canberra, Feb 11  A new research by Australia's Griffith University has found cancer, chronic kidney disease, diabetes and hypertension are the four main comorbidities leading to Covid-19 deaths.

After analysing global databases of 375,859 participants from 14 countries, researchers from the University found chronic kidney disease was statistically the most prominent comorbidity linked to death, reports Xinhua news agency.

They also found hypertension, obesity and diabetes were the most common underlying medical conditions in Covid-19 patients. 

However, unlike the other two comorbidities, obesity did not increase the risk of mortality.

"Comorbidities are frequently cited as risk factors for severe COVID-19 outcomes, however, the degree to which specific comorbidities impact the disease is debatable," said co-lead author Adam Taylor.

"This is a global study covering all comorbidities reported to be involved in the exacerbation of COVID-19 leading to death. It allows us to identify specific comorbidities that have higher risk in patients and identify COVID-19 high-risk groups."

Lead author Professor Suresh Mahlingam said Covid-19 was associated with increased clot strength, so patients with hypertension and diabetes could have a higher risk of developing life-threatening thrombotic complications.

For Covid-19 patients with chronic kidney disease, the risk of mortality was higher in cases with end-stage renal disease compared to chronic renal disease.

The researchers said further investigation is required to explain the higher prevalence of these comorbidities in infected patients.