Published in the August 2005 issue of Today’s Hospitalist
When it comes to evaluating how hospitalist programs reduce length of stay and streamline costs, most researchers have compared hospitalists to community-based physicians who don’t work exclusively in the inpatient setting. Relatively few studies, however, have asked the more interesting question: How do different hospitalist programs working under the same roof stack up?
A new study out of southeast Michigan that asked that question found some interesting differences in the way that two groups of hospitalists are structured. Perhaps more significantly, researchers also found significant variation in how each controls length of stay and costs of care.
The study, which was published in the May issue of the American Journal of Medicine, examined the performance of three groups of physicians working at a large Michigan tertiary care center: 15 academic hospitalists employed by the hospital; a group of 18 private-practice hospitalists; and 63 community-based internists from 21 different groups managing their own inpatients. The study examined the care of nearly 11,000 patients between July 2001 and June 2002.
It came as little surprise that patients treated by the two groups of hospitalists had lower lengths of stay and relatively higher rates of short-stay admissions (visits of less than 24 hours) than community physicians. When the study compared the outcomes of the two groups of hospitalists, however, surprises started to surface.
The academic hospitalists in the study, it turns out, not only lowered costs of care for their patients, but achieved a length of stay that was 13 percent lower for comparable patient cohorts. Lakshmi Halasyamani, MD, the study’s lead author and associate chair of the department of medicine at Saint Joseph Mercy Hospital in Ann Arbor, the site of the study, says the results surprised even the researchers working on the study.
“I expected to see a difference in length of stay between the two hospitalist groups,” she explains, “but I didn’t expect it to be as large as it was, especially because academic services are often viewed as less efficient given the combined clinical care and teaching priorities.”
When length of stay was adjusted for severity of illness, researchers found differences between the three groups. The academic hospitalist group had a 20 percent relative risk reduction (-0.72 absolute difference) in case-mix adjusted length of stay when compared with the community physicians (p< 0.0001). The private hospitalist group also had a length of stay difference compared with the community physicians, but the difference was 8 percent (p=0.049). Finally, academic hospitalists' relative length of stay was 13 percent shorter than that of private hospitalists (p=0.0002). When researchers looked at absolute mean variable costs and adjusted them for case mix, they found that academic hospitalists reduced costs on average by $173 per case (10 percent) compared with private hospitalists whose costs were $109 lower on average (6 percent) than community physicians. There was no statistical difference in cost reduction between the academic and private hospitalist groups. Differences in structure
Beyond length of stay and costs of care, there were few significant differences in outcomes among the three groups. Both 30-day readmission rates and in-hospital mortality rates, for example, did not differ significantly.
In examining the composition and structure of the three groups, however, researchers encountered factors that may explain the differences in outcomes. The academic service’s patients, for example, were slightly younger and had a mean age of 62 years, compared to 65.7 years for the private-practice hospitalists and 68.5 years for the community-based physicians.
Researchers also uncovered differences in the demographics of the three groups. The youngest hospitalists were found in the academic group, where the average age was 36. Private-practice hospitalists, by comparison, had an average age of 39, while the average age among community internists was 49.
All of the academic hospitalists, for example, use the hospital’s computerized physician order entry system, and most follow hospital protocols for heart failure, acute myocardial infarction and community-acquired pneumonia. Dr. Halasyamani thinks those factors probably helped academic hospitalists be more efficient in their care delivery.
When researchers compared the structure of the two hospitalist groups, they found significant differences in work schedules, institutional support and the number of physicians involved in a single patient’s care.
In terms of scheduling, the 15-member academic group worked in half-month blocks for an average of 14 weeks over the one-year period. The academic hospitalists also received administrative and clinical support.
Among the private-practice hospitalists, there were 10 fulltime physicians and eight moonlighters covering weekends and holidays. The 10 full-time physicians worked 8 a.m. to 6 p.m. on weekdays and covered 25 percent of weekends and holidays for a total of approximately 40 weeks annually. The remainder of patient care was covered by group-affiliated moonlighting hospitalists. Nights (6 p.m. to 8 a.m.) were covered by housestaff.
The 63 community physicians typically rounded daily between 7 a.m. and 10 a.m. and were supported by housestaff during other hours.
The effect of fewer handoffs
While the results of the study didn’t provide any clear answers for the variation in length of stay or overall costs, Dr. Halasyamani says the findings point out some likely reasons for the differences. She thinks a major factor involves handoffs.
“With the academic model, the number of patient handoffs was reduced by more than 100 percent when compared to private hospitalists,” Dr. Halasyamani explains. While she suspects that fewer handoffs helped the academic hospitalists drive down length of stay, she is quick to point out that the study did not look at that issue specifically, so she has no data to back up her hunch.
Dr. Halasyamani says that the study’s data, however, do make a strong case for future researchers to examine how the number of handoffs influences quality and the use of resources. She also says her study shows why hospitalists need to identify tools and strategies to help mitigate the risks of handoffs.
Dr. Halasyamani also hypothesizes that the academic hospitalists’ relationship with the hospital may have helped them drive down length of stay and reduce costs of care. “The alignment of the hospitalist group and the institution “from a financial and quality perspective “makes a difference and was a key issue in our study,” she says.
Since the study was published, Dr. Halasyamani adds, hospital administrators have begun looking more closely at how all physicians caring for inpatients use resources and how they organize their care. Hospital administrators have encouraged the researchers to perform subset analyses of their findings by patient population and diagnosis.
Limits of the study
While Dr. Halasyamani thinks the study’s findings are significant, she points out that limitations in its design may limit its applicability to other facilities.
For one, the ability to adequately review case mix and risk-adjust study participants “a problem she says is “an issue across the literature” “may have contributed to some of the differences in outcomes and length of stay.
She also acknowledges some potential problems in retrospective studies that rely on diagnosis codes. For example, a patient deemed as having respiratory failure might not be intubated but may require a lot of oxygen and almost end up in the ICU, something that a back-end cost review won’t necessarily reflect.
“All of these things can make a big difference at the individual patient level,” she adds. “You can look at a hospital [record] and think that it took 10 days to take care of a pneumonia, when it was really respiratory failure in a patient who almost was admitted to the ICU.”
Bonnie Darves is a freelance writer specializing in health care. She is based in Lake Oswego, Ore.