Urologists’ Prescribing of Gonadotropin-Releasing Hormone Agonists for Prostate Cancer Vary by Practice Affiliation

Neil Canavan

June 2013, Vol 4, No 5 - Economics of Cancer Care

New Orleans, LA—An analysis comparing the prescribing habits of urology practices shows that, despite treatment guideline recommendations to the contrary, gonadotropin-releasing hormone (GnRH) agonists, which are only indicated for the palliative treatment of advanced prostate cancer, are routinely prescribed for patients with localized, low- or intermediate-grade prostate cancer, particularly by urologists who have no practice affiliation with a medical school.

“Such treatment patterns are not consistent with patient-centered clinical guidelines and [are] unlikely to have significant survival benefit,” noted lead investigator, Ruben G. Quek, MPhil, with the American Can­cer Society and Emory University, Atlanta, GA, and colleagues. They presented their findings at the 2013 International Society for Pharmaco­economics and Outcomes Research annual conference.

Conducting a retrospective study by using the American Medical Associ­ation and Medicare databases, the team looked at the prescribing habits of academic-affiliated and non–academic-affiliated urology practices of GnRH for prostate cancer just before and just after the 2003 Medicare Modernization Act (MMA).

The measures introduced by the MMA were intended to curtail reimbursement rates for GnRH agonists, which promoted this investigation of the effect of the new reimbursement rates on urologists’ prescribing practices for patients with cancer.

The analysis included the medical rec­ords of 10,301 patients, who were treated by 1577 urologists. All patients (aged ≥66 years) were diagnosed between 2003 and 2005 with localized, low- to intermediate-grade prostate cancer.

The team looked at GnRH agonists that were prescribed for patients within 6 months of diagnosis—a regimen that is at variance with clinical guidelines—and then asked if a treatment bias according to a urologist’s practice affiliations could be demonstrated.

The results showed that compared with their medical school–affiliated colleagues, the patients managed by urologists who are not affiliated with a medical school were significantly more likely to receive GnRH agonists as part of their treatment regimen, which is against current recommendations.

After the MMA went into effect, the nonaffiliated prescribers tapered off in their activities somewhat, but they were still significantly more likely to administer GnRH agonists than the affiliated urology practices. This unwarranted treatment, although further diminished, still persisted through 2005.
“Even though the overall odds of patients receiving unnecessary GnRH agonists decreased after the MMA reimbursement reduction, urologists without practice affiliations with medical schools were still significantly more likely to prescribe GnRH agonists,” concluded Mr Quek and his colleagues.