Friday, March 25, 2011

Low-value health care: coronary CT screening in Texas

Like many states, Texas is facing a fiscal crisis caused by decreased revenue from the economic recession and skyrocketing health care costs. Even without the expansion of publicly financed health insurance mandated by last year's health reform law, the percentage of the state budget devoted to Medicaid expenses is projected to rise from 28 percent to 46 percent by 2020, even faster if the law withstands current constitutional challenges. The situation is so dire that the Texas Tribune and the New York Times recently reported that state health officials have been considering measures to reduce overuse of pricey neonatal intensive care units by refusing to cover elective labor inductions or Cesarean sections without medical indications.

That isn't a bad idea from a health outcomes perspective - since babies who are delivered prematurely for convenience reasons, or delivered surgically rather than through a trial of labor, are more likely to experience complications than others - but the fact that it's being seriously discussed illustrates just how desperate they are. Texas is, after all, represented by Senator Kay Bailey Hutchinson, who last October wrote a largely inaccurate editorial in Politico attacking the U.S. Preventive Services Task Force's role in making recommendations for clinical preventive services and concluding that "patients and their doctors - not the federal government - should have the freedom to decide what is best."

So an outside observer might reasonably be at a loss to understand why since September 1, 2009, Texas has mandated insurance coverage for screening coronary CT scans every 5 years for an estimated 2.4 million people at risk for coronary artery disease. According to an analysis published in the Archives of Internal Medicine, at $200 per test, the law could lead to nearly half a billion (!) dollars in new health expenditures, cause about 200 new cancers, uncover at least 190,000 incidental findings of questionable clinical significance (most requiring additional testing leading to increased costs, inconvenience, and harms), and possibly save zero lives. Even if some patients are reclassified from the "moderate risk" to the "high risk" category by a coronary calcium score, there is no evidence that cardiovascular imaging results have any effect on smoking cessation, dietary habits, physical activity, or even medication prescribing.

The American College of Physicians recently published a clinical practice guideline that encouraged physicians to practice "high-value, cost-conscious health care," such as not ordering routine X-rays, CT scans, or MRI for patients presenting with uncomplicated low back pain. Good for them, but hopefully they'll set their sights a little higher next time, literally and figuratively. A few years ago, I co-authored an editorial that proposed a rational framework for establishing the utility of coronary imaging in asymptomatic patients:

For CAD risk stratification or a screening test to aid in the evaluation of asymptomatic, intermediate-risk patients, it must answer the following three questions. Does the test independently predict coronary events beyond Framingham risk scoring alone? Does a positive test occur often enough in those at highest risk of CAD to make mass application worth it (i.e., sufficient yield)? Do patients identified as high risk by the test stand to benefit from therapy? If the answer to any of these questions is uncertain, there is no way to know if applying such a test to large populations of asymptomatic patients would be beneficial. Even with adequate data to answer these questions, the test actually could be harmful by causing false-positive results, providing false reassurance, or by labeling persons with a disease when interventions are not effective.

Thus far, there is absolutely no proof that patients identified as "high risk" by coronary CT screening benefit from intensified therapy. Therefore, coronary CT screening is low-value health care at best, and wasteful and potentially harmful at worst. Before slashing Medicaid expenditures, Texas should first repeal this ill-conceived mandate.