People with underlying health conditions such as heart disease and diabetes are six times more likely to be hospitalized with COVID-19 and have a risk of coronavirus-related death 12 times higher than otherwise healthy individuals, a US study found.

Men were more likely than women to have bad outcomes, and the prevalence of hospitalizations and deaths were highest among patients aged 70 years and older, according to a US Centers for Disease Control and Prevention (CDC) report that confirmed similar reports from outbreak hotspots in recent months.

"These findings are consistent with previous reports that found that severe outcomes increased with age and underlying condition, and males were hospitalized at a higher rate than were females," the CDC wrote in its report issued on Monday.

By analyzing data from over 1.3 million COVID-19 patients between January 22 to May 30, the CDC found that the most prevalent underlying health conditions in more severe cases were cardiovascular disease, diabetes and chronic lung disease.

About 45 percent of patients who had underlying health conditions were hospitalized, compared with 7.6 percent of those without such chronic health issues. Death due to COVID-19 was reported in 19.5 percent of patients with health complications, compared with 1.6 percent of people who did not suffer from chronic illnesses.

This highlights the continued need for mitigation strategies, especially for people at risk, the agency said.

These data are used to monitor trends in the illness and inform policies and practices to reduce transmission in the United States, the CDC said.

Health experts have said people with such risk factors need to take extra precautions as U.S. states reopen and relax restrictions in movement that were implemented to curb the pandemic.