Referral rates for physicians nearly double in 10 years

More outpatient visits are ending with the doctor recommending that the patient make an appointment to see another physician. It's a fact that probably is contributing to rising health care costs, says a Jan. 23 study in Archives of Internal Medicine.

Between 1999 and 2009, the percentage of ambulatory visits that resulted in a referral nearly doubled from 4.8% to 9.3%, the study said (link).

Researchers evaluated Centers for Disease Control and Prevention data from more than 845,000 patient visits between 1993 and 2009, focusing on the period from 1999 to 2009. They were surprised by the increase in referrals, said Bruce Landon, MD, MSc, study co-author and professor with Harvard Medical School's Dept. of Health Care Policy.

"It is not something we would have predicted, particularly given the relative stability up until 10 years ago," he said.

Referral rates were high for both specialists and primary care physicians. The number of outpatient visits to specialists that resulted in referrals rose from 11 million in 1999 to 38 million in 2009. Primary care physician visits resulting in referrals increased from 22 million to 51 million during the period.

Despite the increases, the proportion of visits that went to specialists remained stable at about 50% in 1999 and 2009. That stability is probably due to multiple factors, including the overall increase in ambulatory patient visits, a sharp decrease in patient self-referrals and the fact that not all referrals are to a specialist -- specialists also refer to primary care physicians, the study said.

Because they have a financial incentive to keep patients within their practice, the rise in referral rates was significantly smaller for physicians who owned at least a portion of their practice compared with nonowner physicians, the study said. Doctors who said more than 50% of their income came from managed care contracts also saw less of an increase in referrals.

The study authors attributed rising referral rates in part to the increasing specialization of medicine and time pressures during patient visits. They said more research is needed to determine the impact of rising rates on the costs of health care.

"This evolution in care patterns may be playing a role in the rising trajectory of health care spending in the United States because referrals to specialists may lead to increased use of higher-cost services," the study said.

Whether referrals will continue to increase is difficult to predict, Dr. Landon said.

"If we see a strengthening of the primary care system, implementation of the patient-centered medical home and growth of [accountable care organizations] and bundled payment, then I would say no," he said. "If things continue unchecked, however, I see no reason why these trends would not continue."