In the pursuit of “value-based care”, innovators are consistently looking for ways to deliver similar outcomes without the risks and resource utilization of inpatient hospitalization. One of these realms is the evaluation of transient ischemic attack. Most of the recommended follow-up tests are only relatively urgent in nature, and with medical management the typical mainstay of therapy. As serious considerations go, it seems ripe a candidate for outpatient management.
This retrospective look at outcomes from Canada, however, suggests there may be pitfalls to such a strategy. These authors reviewed the outcomes of 8,540 patients presenting with TIA or minor stroke, and compared those either admitted to the hospital at the index visit with those discharged, and among those discharged, referral to a specialized follow-up clinic or not.
Patients admitted to the hospital, by all measures, had more severe cerebrovascular disease – as evidenced by duration of symptoms, ABCD2 scores, diagnosis of minor stroke, and other comorbidities. However, despite this, following hospitalization, these patients had the lowest risk or recurrent stroke or TIA within one year. The benefit, presumably, comes from increased likelihood of undergoing risk stratification and treatment – carotid imaging, echocardiography, appropriate anticoagulation, appropriate antithrombotic therapy, and the like. Then, among the discharged, various adjusted and propensity matched analysis demonstrated a protective effect of referral to specialty outpatient follow-up against death, but not for stroke or TIA. These data do not have the granularity to fully describe whether the excess deaths were in some fashion related to cerebrovascular disease.
Most of the absolute differences in outcomes between groups are small – a few percentage points each, and smaller after adjustment. That said, it’s probably clearly superior care, as configured in Ontario during this time frame, to have been admitted to the hospital. As TIA evaluation, and other similar conditions, move to outpatient pathways rather than traditional hospitalization, this represents an important reminder of potential risks of degradation in thoroughness and quality.
“Association between hospitalization and care after transient ischemic attack or minor stroke”
https://www.ncbi.nlm.nih.gov/pubmed/27016521
What were these magical treatments that prevented death but not stroke or TIA?
This is highly reminiscent of the observational studies of the influenza vaccine that show the flu vaccine prevents deaths even outside the flu season:
Eurich DT, Marrie TJ, Johnstone J, Majumdar SR. Mortality reduction with influenza vaccine in patients with pneumonia outside “flu” season: pleiotropic benefits or residual confounding? Am J Respir Crit Care Med. 2008 Sep 1;178(5):527–33.
http://dx.doi.org/10.1164/rccm.200802-282OC.
The underlying mechanism is residual confounding: people with a better prognosis are more likely to get admitted and sent to the stroke prevention clinics, so the same people are less likely to have bad outcomes.
Yep, it's retrospective kludge so you have put on your imaginarum hat and respect the unmeasured confounders.
However, the reason I find this one particularly interesting is the folks who get admitted were mostly true minor strokes or high-risk TIAs, while the remainder were discharged to outpatient follow-up. In theory, because the hospitalized group was the highest-risk, they should have the worst one-year outcomes before any adjustments – but they don't. The reasonable association to make is they've more reliably been objectively evaluated with carotid imaging, echo, etc. and had more appropriate anti-coagulant and anti-thrombotic therapy initiated.
That said, the bottom-line here is just a general point: "if you take an inpatient work-up and move it to outpatient, make sure it's just as timely and thorough so there's no drop off in quality".