What specific pre-existing conditions put people especially at risk?

Older adults and people of any age who have serious underlying medical conditions may be at higher risk for more severe complications from COVID-19. This includes people with chronic lung disease or moderate to severe asthma; people who have serious heart conditions; people who are immunocompromised; people with severe obesity (body mass index [BMI] of 40 or higher); people with diabetes; people with chronic kidney disease undergoing dialysis; and people with liver disease.