Eileen Doherty, executive director of the gerontological society, recently asked about 100 seniors attending a Medicare meeting in suburban Littleton how many had a regular doctor.
"Only one person raised their hand," she said. "When I asked how many have had trouble finding a doctor, about half the hands went up, and when I asked how many had to travel farther to get medical care, almost all the hands went up."
Some advocates say the problem seems to have stabilized after their groups surveyed doctors' offices and distributed lists of physicians still accepting Medicare patients.
Sometimes, however, knowing how to navigate the system doesn't help.
Dorothy Rupert represented Boulder in the state Legislature for 14 years, working most of that time to make health care more available to Colorado's poor. She knew the state's health-care system inside out and grew concerned when new residents of The Academy retirement community told her how hard it was to find a doctor.
But it wasn't until last year, on her last day as the term-limited Democratic leader of the state Senate, that she experienced firsthand the worsening Medicare doctor shortage.
Her husband, then 79, suffered a severe stroke and, after the frantic 911 call, the emergency room and the intensive care unit, she began trying to reach his physician of more than 20 years.
After days of repeated calls, the doctor's office manager "finally called to say he wasn't Dick's doctor anymore," recalled Rupert, still an activist at 76. "It was so hard to understand."
After a months-long search -- aided by a private attorney -- for a Medicare-accepting physician and a nursing home she could afford, Rupert finally moved her husband to a facility near their son in Louisiana, where health care costs less and more doctors accept Medicare.
"It wasn't that people [in Colorado] weren't trying to help," Rupert said, "but if the access isn't there, it doesn't matter."
Access often isn't there. According to recent surveys, only 4 primary-care physicians in 10 accept new Medicare patients in Colorado. In Colorado Springs -- where a former judge, military retirees and leaders of prominent Christian ministries are among those unable to find doctors -- the rate is closer to 1 in 10.
Increasing numbers of retirees are simply doing without a physician until they get sick. Hospital emergency departments are serving as de facto examination rooms for seniors, and many of the patients who arrive at the Penrose-St. Francis Senior Health Center have gone without health care for a while.