A new national study suggests patients may receive certain types of elective surgeries more commonly based on where they live — a factor of regional physicians’ experience and training — as opposed to patient preferences.

According to the new report from the Dartmouth Atlas Project, the rates of Medicare patients receiving the same elective surgical procedures varies greatly based on where they live not only around the country, but from region to region within the state.

Based on the rates of Medicare beneficiaries from 2008-10, those patients in Paducah were about twice as likely to receive surgery for back pain as were patients in Lexington.

Medicare patients in Mayfield were slightly more likely to receive a percutaneous coronary intervention (angioplasty) than patients in both Paducah and Louisville, while those two cities were also more likely to perform knee replacement surgeries than most major hospital referral regions across Alabama, Kentucky, Mississippi and Tennessee.

Shannon Brownlee, lead author of the report and instructor at the Dartmouth Institute for Health Policy and Clinical Practice, said the purpose of the study was to highlight these regional differences in elective surgeries, which the researchers attribute to physician recommendations, as opposed to patient preferences.

“Many patients aren’t even aware that the decision about elective surgeries are even their choice, and that it’s theirs to make,” Brownlee said in a news conference during the study’s release on Dec. 12. “Instead, patients routinely delegate their decisions to their doctor because the doctor knows best.

“It’s often a physician’s preference or opinion that ends up winning the day.”

The statistics for the east south central region measured the rates of common surgical procedures and PSA testing among Medicare beneficiaries between 2008-10.

Rates are expressed per 1,000 Medicare beneficiaries and are adjusted based on age, race and sex (where appropriate). According to the report, demographic factors that might affect how common a condition is were taken into account.

The report divided the state into hospital service areas, therefore data is based on where people live and not based on where they are treated. Below is a list of several variations in the state:

n The rate of cholecystectomy — removal of the gallbladder to commonly treat gallstones or other gallbladder issues — between 2008-10 was 6.3 per 1,000 Medicare patients in Paducah; 7.5 in Mayfield; 5.3 in Murray; 4.6 in Louisville; and 3.1 in Lexington.

n The rate of mastectomy between 2008-10 was 1.4 per 1,000 Medicare patients in Paducah; 1 in Louisville; and 0.3 in Lexington. Murray was omitted for 10 or fewer cases during the study period, and Mayfield experienced fewer than 26 cases during the same time frame.

n The rate of PCI between 2008-10 was 10.3 per 1,000 Medicare patients in Mayfield; 10 in Murray; 9.1 in Lexington; 8.9 in Paducah; and 7.4 in Louisville.

n The rate of coronary artery bypass graft — surgery that helps improve blood flow into the heart — between 2008-10 was 5.3 per 1,000 Medicare patients in Mayfield; 4.5 in both Paducah and Murray; 3.7 in Louisville; and 3.2 in Lexington.

During the Institute’s national teleconference, Brownlee said it’s tempting for people to view the regional maps and point to a rural versus urban argument of medical conditions and treatment, but no general statement for this conclusion could be drawn from the report.

David Goodman, co-author and co-principal investigator for the Dartmouth Atlas Project, highlighted the centralized training that physicians receive as another factor in regional differences. A larger number of physicians training at particular academic medical centers could learn the same diagnosis and treatment pattern, leading to surgical signatures within the community.

“Different doctors interpret what’s right for patients differently,” Goodman said.

While the study did not measure individual patient preferences, Goodman said other studies conducted over the years have highlighted that patterns of care do not reflect what patients want necessarily.

It is a legal requirement for physicians to undergo a process of informed consent with their patients before any measures are taken, but Goodman argued it’s only a legal concept and far from the realities of the doctor’s office. Researchers termed the misdiagnoses of patient preferences in elective surgeries as wrong patient error.

“When patients don’t get a chance to be really informed and make a choice, the physician is at risk to prescribe the wrong treatment for the wrong patient,” Brownlee said. Physicians aren’t mind readers and may assume their patients values and preferences are the same as their own, she said.

Call Will Pinkston, a Paducah Sun staff writer, at 270-575-8676 or follow @WCPinkston on Twitter.