WASHINGTON (AP) — Getting older doesn't just mean a risk for physical ailments like heart disease and bum knees: A new report finds as many as 1 in 5 seniors has a mental health or substance abuse problem.

And as the population rapidly ages over the next two decades, millions of baby boomers may have a hard time finding care and services for mental health problems such as depression — because the nation is woefully lacking in doctors, nurses and other health workers trained for their special needs, the Institute of Medicine said Tuesday.

Instead, the country is focused mostly on preparing for the physical health needs of what's been called the silver tsunami.