Update in Primary Care, Feb 2019

I’m just back from the always fun Southern SGIM Annual meeting, in Houston, TX. I had the pleasure of presenting an Update in Primary Care with the great Peter Phan. It’s a great reminder of our evidence base in outpatient medicine, so wanted to share it here as well. Plus a certain Master Educator called me out in his Unknown Vignette discussion, so I heard that I might have some new followers- Welcome!

Here goes!

First up: this RCT published in October 2018 in JAMA compared PT to Arthroscopic surgery for meniscal injury. A big caveat is that patients with locking of the knee were excluded, so this likely is focused on patients with degenerative meniscal injury.

Here are the results: This was a non-inferiority trial, so a low p value means that PT was NON-INFERIOR.

There was no difference in knee function between PT and Surgery at 3, 6, 9, and 24 months. There may have been a improvement at 12 months, but it disappeared by studies end.

Next, what happens to patients with documented Penicillin Allergy? This study from June 2018 in BMJ looked at just that. This was a matched, prospective cohort study that enrolled over 300K adults.

The authors looked at risk of MRSA or C.Diff infections, and controlled for a variety of potential confounders, including: PPI, Antibiotic or steroid use, admission to SNF or hospital, and others.

Patients with a documented Penicillin allergy were 69% more likely to have MRSA and 26% more likely to have C. Diff.

Interesting side note, most patients (95%!) with a documented penicillin allergy are not, in fact, actually allergic to penicillin. So it is worth investigating- get a good history, and consider allergist evaluation even if the allergy seems legit.

Number 3, Aspirin, Aspirin, Aspirin. This has been a super hot topic this year, with lots of studies. We reviewed ASCEND in NEJM, published in October.

This study looked at diabetics on aspirin for primary prevention. This was a prospective RCT that enrolled over 15K diabetics and followed them for 7.5 years.

They were randomized to 100mg of ASA or placebo. 75% of the patients were also on statins. They evaluated a combined CV endpoint (death, MI, TIA, stroke) as well as colon cancer incidence. They also measured major bleeding events.

There was a risk reduction of first vascular event for patients on aspirin, RRR 12%, NNT 91.

However, there was also a 29% increased relative risk of major bleeding in those patients. And no change in cancer rates. So harm from ASA seems to outweigh the benefits in diabetics.

And check these other papers in NEJM: ASPIRE and ASPREE. Also showing more harm than help for aspirin in patients over 70. There is a great Curbsiders episode on this- check that out on your favorite podcast app, and see the link above for the show notes.

There is the first half! Second half coming up soon!

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“Incidental” Pulmonary Hypertension

After the post about incidental findings a few weeks ago, I have been noticing them more and more.  Not sure if I am really chasing more things, or if I have availability bias. Either way, costs and patient anxiety are adding up. 

Anyway, this came up in clinic recently: a surprise finding of pulmonary hypertension. An excellent resident came to me with his plan, which was perfect, but I have found myself looking this up a time or two. Thought you all might appreciate a review, as I did.

Typically, pulmonary hypertension is found on an echocardiogram, as it was in this case. The most common symptoms are exertional dyspnea, lethargy, and fatigue; common reasons to get an echo.  This really isn’t incidental, but more commonly just “surprise, now what do i do?” clinical dilemma.

So what next? First, decide if the pulmonary hypertension seems consistent with the patient’s symptoms, and if their values are reasonable to warrant further workup. Initially, patient’s are unable to increase cardiac output to match demand with exertion. So they present with exertional dyspnea and fatigue.  With more advanced PH, they develop right heart hypertrophy and subsequent right heart failure symptoms (edema, abdominal pain from hepatic congestion). Angina is also often present, due to inability to perfuse the subendocardium of the thicker heart wall. Sometimes there is actually compression of the left coronary artery by a big pulmonary artery- leading to angina.

So that sounds like it could be your patient. Are you satisfied with pulmonary hypertension as an explanation?  Echocardiogram estimates pulmonary artery pressure by looking at the jet behind tricuspid regurgitation and the IVC to estimate right atrial pressure.  So if there is no TR, or only weak TR, the PA pressure estimation is less reliable.  Assuming good views,

  • PH likely if PA pressure estimation >50 and TR jet velocity >340 cm/s 
  • PH unlikely if PA Pressure <36 and TR jet velocity is <280 cm/s
  • In between those findings, it is more gray, and a combination of lower pressures plus higher jet velocity, or vice versa, could get you a diagnosis.

OK- let’s say our patient has echo findings that fit the “likely” scenario above (both are easy to find on UAB echo reports, FYI).  Next step is to decide if this is secondary PH or idiopathic PH. Ultimately, many of these patients will need a right heart catheterization if specific treatment for PH is indicated (which we are NOT going to be doing in the clinic).  However, there are some common secondary PH syndromes that we can find and treat. Some possible secondary diagnoses:

  • Left sided heart disease: Probably most common reason for PH. This should be clear from the echo you already got (and your history and physical).
  • Lung disease: PH can be due to either COPD or severe restrictive lung disease (lung volumes <50% predicted).  If PFTs are only mildly abnormal, lung disease is probably not to blame for the PH.
    • So order PFTs
  • Sleep Apnea: An increasingly common diagnosis and certainly worth diagnosing and treating.  First ask about potential OSA (snoring, non-restorative sleep, daytime somnolence, headaches), and then screen
    • Overnight PSG is the gold standard, although could consider overnight pulse oximetry at home if sleep study is hard to get and your suspicion is low.  Will likely need the sleep study to get the CPAP.
  • Chronic PTE:  Much less likely, but it is found every now and then.  My practice is to hold off on this evaluation at first unless the PH is severe or the patient has other reasons to make me suspect chronic clots.
    • Usually start with a VQ scan as it is much more sensitive for chronic PE than CTA.
  • Portopulmonary Hypertension: So maybe your patient’s cirrhosis is leading to portal hypertension, backing up to the right side of the heart.  Sort of the opposite of passive hepatic congestion.Hopefully you know if your patient is cirrhotic, but easy enough to investigate if you don’t.
    • LFTs, consider abdominal US.  Keep in mind though, that US is not really going to tell you the difference between hepatic congestion starting in the heart and congestion starting in the liver.
  • Connective Tissue Disease:  Most likely you will also see the interstitial lung disease on your PFTs if this is your diagnosis, but not always. You could wait and get your PFTs first.
    • Rheum labs, specifically ANA, RF, anti-CCP (if high suspicion), ANCA
  • HIV infection can cause PH. Lung biopsy shows plexiform lesions of endothelial cells, that looks the same as idiopathic PAH. Pathogenesis is not clear (at least to me).
    • HIV antibodies
  • Chronic Hemolytic Anemia: Again, you would usually know if your patient has a reason for this, like Sickle Cell Disease.  A big workup is not usually indicated for all patients with pulmonary hypertension.

If none of those fit, then idiopathic PH is more likely, and you should think about referral to pulmonary hypertension clinic. Hopefully that will get you on the right track.  By no means do you have to do all these things at once, but let your patient, their most likely etiologies, and the severity of their symptoms be your guide. Remember, the beauty of outpatient practice is that there is TIME to work these things up in a stepwise process (even if you never feel that you have time in clinic- you do!)

Thoughts, questions, did I get something totally wrong?  Please drop me a line in the comments sections and straighten me out.  Or just let me know that I’m not talking to myself out here!

Pulmonary Artery Angiogram Image above from Up To Date 12.0, which has a great review of this topic, and an algorithm for the workup.

Blue lips are from the pulmonary hypertension association.

Unicorn Sighting

Happy guideline season!

I’ve been hearing about JNC 8 for so long, that I thought it didn’t really exist.  Thanks to some persistent hypertension experts, it is here at long last.  Here’s a quick review of the major points. I’m sure that we will see some commentary in the days and weeks to come, I’ll try to keep you updated on that as well.   I’d love to hear what you think- start the conversation in the comments below.

Higher BP targets

We are used to aiming for 140/90 for most people, and 130/80 for those with CKD, diabetes, CAD, and other comorbidities.  But new evidence  has emerged that these may not be so great, particularly for elderly patients.  So JNC 8 says- Adults 18-60 (even with DM or CKD) should aim for BP <140/90.  We can be a little more relaxed with patients over 60, and aim at 150/90 for them, so long as they don’t have CKD or DM.  Most of this change comes because there really was no outcome data for our prior target, and it seems that getting people to the 140s systolic provides just as much benefit as the 130s range.

Relaxed first line medicine choices

We’ve known that this was coming for a while.  JNC 7 recommended thiazides as first line for all, but there was never any real data to back that up.  So JNC 8 says that we can use thiazides, ACE-I/ARBs, or calcium channel blockers as a first choice for most patients.  They do acknowledge the racial difference in response to ACE inhibition, and recommend that we DON’T use ACE/ARB as first line for our black patients. EXCEPT (there’s always an exception) that for patients with chronic kidney disease (but not necessarily diabetes without ckd), use ACE-I first, no matter the race.

Second, and third, and fourth line medicines

Really not much different here, except there are not really recommendations about when to start two medicines at first visit.  JNC 8 says we can pick a variety of treatment strategies– maximize one medicine at a time, add a second agent before maximizing the first, or start two medicines at once.  When you add agents; pick from that first line list (thiazides, ACE/ARB, CCB) until you’ve used them all, then use aldosterone antagonists, beta blockers, central agents, or other vasodilators.  They do recommend avoiding ACE-I and ARB combos for most patients.

What’s Missing

JNC 7 discussed prehypertension, secondary hypertension, resistant hypertension, adherence, how to measure blood pressure, and lots of other related issues. The JNC 8 group just picked 3 questions that they felt were most important: does starting treatment at a particular threshold improve outcomes, does a particular treatment goal improve outcomes, do various drugs have important differences in risk/benefit calculation and outcomes.  Very evidence based and outcome oriented, which is kind of refreshing.

What about my patients now?

For all of us who have been trying to follow JNC 7 (and the subsequent performance measures created from that guideline), should we go adjusting therapy on our patients to meet new targets?  No, say these experts.  If your patient has a blood pressure of <150/90 on their current therapy, and is doing well, no need to change. Stay tuned to see if any of our performance targets change.

A great big picture algorithm from the JNC 8 group is here, and the link to the guidelines themselves is here (on the JAMA website subscription may be needed).

Here’s a great, plain language summary from the NYT Well blog.