Sunday, June 22, 2008

Identifying CHF patients eligible for hospice care

First - a note on format.

As you may have noticed with Christian's last two posts, and mine today, we are changing the format a little. Instead of having ~3 long posts a week, each of which (usually) references many articles, we are going to be splitting up the content into separate posts but will still be updating the content approximately 3x a week. The same volume of content will still be there; just in multi-post form (usually a 'major'/long post and one or more 'minor'/shorter posts).

We're doing this to make the blog easier to navigate and search - a post's title will more closely reflect its content. In addition it will make it easier for readers to skip topics they're not interested in - you won't have to scan a long post to see what's in there anymore.

We are not going to increase the number of emails a week (this will still be, on average, 3 - the emails will be about the same length too - it'll be the same amount of content just divided up more rationally). All the posts will be clustered together so they'll go out in a single email. RSS readers will just notice several posts coming up at once and can pick and choose which to read. The major difference this will make will be for people who go to the blog directly (which is sooo 2005); if you do just be sure to scroll down to make sure you haven't missed any posts.

Give us feedback about how you like this, or not.

JAGS has a paper on predicting 6 month mortality / hospice eligibility in hospitalized patients with CHF. The data used comes from a prospective trial (done, unfortunately, in the mid 1990s) looking at a case management intervention in heart failure mortality. There were ~280 patients, all over 70 years old, and all were enrolled at the time of discharge from a hospitalization for CHF (mean NYHA heart failure class of 2.5, mean EF of ~40%). The researchers looked at characteristics of subjects at the time they were enrolled, compared differences between those that were dead at 6 months (n=43) and those that were living, and created a scoring system to predict 6 month mortality.

The four characteristics which independently predicted 6 month mortality were: BUN over 30mg/dL, systolic blood pressure less than 120 mmHg, presence of peripheral vascular disease, and serum Na less than 135 mEq/L. Patients who had 3 or 4 of these risk factors had a 66% 6 month mortality (41% for 2 risk factors, 16% for 1, 4% for none). Only 9 patients, however, had a 3-4 risk factors. The negative predictive value of a score of 3-4 was 86% (86% of patients who had scores less than 3 were in fact alive at 6 months).

Some comments.... The need for such an index/risk score is compelling, as there are no decent, objective (i.e. not clinician assessment) indices/ways of predicting 6 month mortality in patients with CHF, and a relatively simple scoring system like this could be useful for 1) establishing hospice eligibility, but more importantly 2) helping clinicians identify CHF patients who have 'acute' palliative care needs (need for discussions about prognosis, code status, advance care and terminal care planning, etc.). CHF is devilishly difficult to prognostic in, so any objective, data-backed guidance is welcome. On the other hand this index is not ready for clinical use. The data come from the mid-1990s and while CHF mortality hasn't improved dramatically (I think) in that time there have been more widespread identification and use of interventions which incrementally improve survival (ICDs, resynchronization therapy, spironolactone, etc.). And while an N of 43 (dead patients) is unfortunately not atypical for these sorts of studies, it's pretty low, and the N of 9 for patients who actually had 3-4 risk factors is low enough to immediately halt any clinical application of this (other than to reinforce the prognostic importance of PVD, hyponatremia, etc.). 'Further study is needed' (of course, but when can you not say that?).

The NHPCO guidelines for hospice eligibility for CHF patients are well-recognized for being largely...empiric (to be polite about it - although based on the best available data and wisdom at the time). Perhaps the NHPCO could fund a validation study using contemporary data from multiple institutions and many more patients? Unlike my ramblings in my prior post about cancer and prognosis, I perceive prognostic uncertainty to be a real issue in limiting the availability of hospice/palliative care in CHF.

ResearchBlogging.orgHuynh, B.C., Rovner, A., Rich, M.W. (2008). Identification of Older Patients with Heart Failure Who May Be Candidates for Hospice Care: Development of a Simple Four-Item Risk Score. Journal of the American Geriatrics Society, 56(6), 1111-1115. DOI: 10.1111/j.1532-5415.2008.01756.x