Wednesday, September 5, 2012

Shared Decision Making for Hip and Knee Replacement Candidates

Osteoarthritis (a.k.a "degenerative arthritis) of the hip and knee just... sucks. Characterized by activity-related pain in the affected joint, many otherwise physically fit persons have to resort to pills, injections and, finally, an appointment with an orthopedic surgeon to talk about joint replacement surgery.

What is less appreciated is that osteoarthritis can have a waxing and waning course with periods of relative remissions. What's more, conservative treatment options can lessen or delay the need for surgery. Last but not least, the surgery itself involves months of recovery and the possibility of a nasty complication.

The primary care physician Disease Management Care Blog presided over this many times with its arthritis patients.  It was generally reluctant to refer a patient to an orthopedic surgeon because it knew that the patients would be more interested in the potential benefits and pay less attention to the downsides of surgery.

Enter shared decision making (SDM). Defined as care that is respectful of and responsive to individual patient preferences, needs, and values and ensures that patient values guide all clinical decisions, the premise is that by giving patients the information they need, they'll be able to ultimately determine the course of their care.  That would include patients with severe hip or knee osteoarthritis who are thinking about surgery but who also need to consider the option of conservative management.

That's why this just-published Health Affairs study is noteworthy. All the 27 orthopedic surgeons in the 5 Group Health Cooperative clinics introduced shared decision making (SDM) for patients who were being evaluated with knee or hip osteoarthritis.  The intervention consisted of DVDs and booklets (from this company) that were ordered by the surgeon prior to an appointment.  The materials could also be viewed on Group Health's website at any time.

The study itself was quasi-experimental.  To be included in the study, patients had to 1) have knee or hip arthritis, 2) ) be continuously enrolled in the Group Health Plan for 12 months prior to the orthopedic clinic visit and 3) have a visit itself that was first index visit by the patient for that problem being evaluated by that particular specialty.

Outcomes from the 18 months of the SDM intervention period (January 2009 through July of 2010) were compared to the observation period of January 2007 through July of 2008.

Recall that the surgeon had to proactively order the SDM prior to the visit.  As a result, only 41% of the hip patients and 28% of the knee patients received the DVD, pamphlet or viewed the on-line materials.
Nonetheless, during the 6 months after the initial visit, the SDM patient population had 0.34 hip operations per 180 person-days (your DMCB offers an explanation of this counter-intuitive metric below*), compared to the control population of 0.46.  The difference was statistically significant. 

There was also a statistically significant reduction in knee operations: 0.09 per 180 person-days vs 0.16 per 180 person-days. 

All the differences held up after the authors statistically adjusted for differences in age, sex, obesity, co-morbid conditions, use of prior x-rays, joint injections, insurance factors and the clinic site.

Like all good authors writing in a high quality journal, they point out that this research was not pristine. The comparison period may not have been a representative baseline and, from 2008 to 2009, other factors may have caused a drop in hip and knee surgeries.

Nonetheless, this is an example of a "real world" study that credibly demonstrates that when osteoarthritis patients are exposed to SDM, more will opt for conservative management.  While that helps decrease health care utilization and ultimately costs, that's not the most important point: the patients who really wanted surgery got it and the patients who were less sure about the benefits of surgery chose not to have it.  What's more, this didn't involve a lot of expensive face-to-face care management, it involved some DVDs.

The DMCB cautions that this successful study was carried out in a highly integrated delivery system and may not be transferable to other practice settings.  That being said, as Accountable Care Organizations struggle to meet their patients' expectations and save money, this application of SDM may represent an important option.

*The DMCB interprets "180 patient days" as one patient being followed for the entire 6 months of the study.  If that's correct, the average SDM knee patient referred to a Group Health orthopedist had a 34% chance of getting surgery versus a 46% chance in the prior control group.  For the knee patients, it was 9% vs. 16%

1 comment:

Dave Foster said...

Great to see the results of this study finally published. My hope is that further studies will actually collect preference data from the patient, with a pre-intent survey as well. By "pre" I mean before the patient does the activity with the shared decision aid. That would help illustrate whether there is a connection between the use of the tool and reduction in invasive procedures.