San Francisco

MEDICARE has suddenly taken center stage in American politics, with Democrats now trying to score an advantage from the unpopularity of the Republican plan to overhaul the government health insurance program. Apart from the politics, though, Medicare’s financing challenges are worsening: this month, Medicare’s trustees projected that the insurance program would become insolvent by 2024, five years earlier than previously estimated.

Much has been said about the growing gap between the program’s spending and revenues — a gap that will widen as baby boomers retire — but little attention has been focused on a problem staring us in the face: Medicare spends a fortune each year on procedures that have no proven benefit and should not be covered. Examples abound:

 Medicare pays for routine screening colonoscopies in patients over 75 even though the United States Preventive Services Task Force, an independent panel of experts financed by the Department of Health and Human Services, advises against them (and against any colonoscopies for patients over 85), because it takes at least eight years to realize any benefits from the procedure. Moreover, colonoscopies carry risks of serious complications (like perforations) and often lead to further unnecessary procedures (like biopsies). In 2009, Medicare paid doctors more than $100 million for nearly 550,000 screening colonoscopies; around 40 percent were for patients over 75.

 The task force recommends against screening for prostate cancer in men 75 and older, and screening for cervical cancer in women 65 and older who have had a previous normal Pap smear, but Medicare spent more than $50 million in 2008 on such screenings, as well as additional money on unnecessary procedures that often follow.

 Two recent randomized trials found that patients receiving two popular procedures for vertebral fractures, kyphoplasty and vertebroplasty, experienced no more relief than those receiving a sham procedure. Besides being ineffective, these procedures carry considerable risks. Nevertheless, Medicare pays for 100,000 of these procedures a year, at a cost of around $1 billion.