Articles for SLPs: Predictors of Aspiration Pnuemonia
If you're a medical SLP who's not familiar with Dr. Susan Langmore, I have to automatically assume you've probably been living under a rock and will send help ASAP!! The amazing Dr. L is the crusader of swallowing disorders, the developer of flexible endoscopy for swallowing (FEES), and an incredible researcher - You know how some people idolize celebrities? Well, in my mind, she's better than any celebrity idol.
In 1998, Dr. Langmore, along with six brilliant colleagues, published a research study titled "Predictors of Aspiration Pneumonia: How Important is Dysphagia?" that completely ROCKED the dysphagia world and challenged everything SLPs have ever been taught!”
In my last blog post, I talked about the Three Pillars of Aspiration - the three conditions that must exist for a patient to be at high risk for aspiration penumonia: compromised immune system, presence of aspiration, and poor oral care.
And we learned that dysphagia is only one piece of the puzzle.
But can we actually predict who's at higher risk for aspiration pnuemonia based on their other conditions?
The answer is YES, we can!
SO WHAT ARE THE DEETS?
In 1998, Dr. Langmore conducted a research study involving 189 elderly patients. 160 of them presented with one or more medical diagnoses including CHF, COPD, neurological disease, GI disease, and stroke. The control group consisted of 29 healthy subjects. Everyone was assessed for oropharyngeal/esophageal swallowing and feeding status, functional status, medical status, and oral/dental status.
Then she followed the patients until they developed aspiration pneumonia, for up to 4 years.
SO... WHAT HAPPENED?
OVERALL RESULTS: Of the 189 subjects, 41 developed aspiration pneumonia for an overall incidence rate of 21.7%. The average time to development of pneumonia after baseline testing was 329 days, or 11 months.
SETTING: The highest incidence of aspiration pneumonia occurred in the nursing home patients (44%). Only 19% of inpatients and 9% of outpatients experienced pneumonia.
MEDICAL DX: When looking at patients by medical diagnosis, 27% of the patients with stroke, 33% with other neurologic disease, and 32% of the patients with either COPD, CHF, or GI disease developed aspiration pneumonia. Subjects with both COPD and GI disease had nearly a 50% incidence of pneumonia. No one in the control group developed pneumonia.
GERD AND PEG TUBES: Of subjects who aspirated, 28% had documented GERD and 27% were tube fed.
CHARACTERISTICS OF ASPIRATE: Of the subjects with aspiration pneumonia, 81% had oropharyngeal dysphagia, 58% aspirated liquid, 27% aspirated food, and 50% aspirated secretions.
FEEDING STATUS: 41% of subjects who developed aspiration pneumonia were dependent on others to feed them compared with only 6% of the subjects without aspiration pneumonia. This dependency was also reflected in their need for oral care.
DENTAL STATUS: Being edentulous had no effect on the development of aspiration pneumonia. Those with decayed teeth or who reported they never/rarely brushed their teeth had a higher instance of aspiration pneumonia. There was no correlation of rate of stimulated salivary flow or xerostomia to aspiration pneumonia.
In summary, Dr. Langmore found the following conditions to be the most predictive of aspiration pneumonia and *spoiler alert* dysphagia did not make the list:
1. Dependency for feeding 2. Dependent for oral care 3. Number of decayed teeth 4. Tube feeding 5. More than one medical diagnosis 6. Number of medications 7. Smoking
HERE ARE THE MAJOR KEY POINTS:
Aspiration MUST occur for there to be pneumonia. I'll say it again - If the patient doesn't aspirate, there's NO POSSIBLE WAY to develop aspiration pneumonia. And even if they do, aspiration will only lead to pneumonia if the material aspirated is pathogenic to the lungs and the immune system is compromised. So all that flash/transient/deep laryngeal penetration stuff, while it *may* be indicative of a swallowing disorder - but that's still a big maaaaybe, because healthy people penetrate. ALL. THE. TIME. - it doesn't mean the patient immediately needs to go on the most conservative diet possible. A little penetration is completely normal.
Regardless of age, a patient is still at risk. Previous reports have suggested that advanced age is associated with an increase in pneumonia but this was not evident in Langmore's study. That means 30-year old Matt may be as much at risk as 90-year old Mildred.
Reduced level of alertness was not found to be associated with increased pneumonia. This finding was in contrast to other older studies that indicated alertness levels contributed to aspiration pneumonia. Now, I'm not saying go feed steak dinners to the patient who can barely keep their eyes open for 30-seconds, but maybe you could reconsider keeping 90-year old Mildred on that crappy puree/nectar diet just because she gets a little drowsy in the afternoons. I mean, doesn't everyone?
Aspiration of food was significantly more likely to be associated with pneumonia than aspiration of liquids. Okay, sooo... I'm on this boat; before I knew the research behind this, I was the #1 offender of trying to prevent aspiration of liquids, even if it means being ultra-conservative with my recommendations. But on second thought, why exactly are we running around thickening liquids left and right like a crazy person but patients are allowed to have solids with no regulations when it's the SOLIDS that could potentially have the most harm?
Delayed swallow initiation and excess residue were only significant as they occurred with pureed food, but not with liquids. Crap, guilty again. I need to find 90-year-old Mildred and apologize now that I know she doesn't need to be on nectar thickened liquids just because she had a little delayed swallow initiation with her juice sips during that darn swallow study.
Aspiration of secretions and excess secretions in the mouth wereboth significantly associated with pneumonia in dentate subjects. Looks like if you're aspirating anything, oral bacteria is NOT the one to mess around with. So regardless if you have teeth or not, CLEAN THAT MOUTH (...but seriously, especially if you have teeth)!!
Documented aspiration on an instrumental swallow study was NOT a significant predictor of pneumonia. Only about 38% of documented aspirators developed pneumonia, meaning although instrumental results are sensitive, they are not very specific predictors. Again, we have to look at the *overall* picture and not strictly focus on the fact that someone aspirated a couple times during the swallow study.
Patients with COPD, GI disease, and CHF are equally at risk. Dysphagia in stroke and neurological populations have always been kinda obvious (because brain damage = possibility of dysfunction... duh right?) but unfortunately, other patient populations that are equally at risk are frequently overlooked during the screening process, especially in acute care settings.
And most importantly of all - *drum roll please* -
"DYSPHAGIA BY ITSELF IS NOT SUFFICIENT ENOUGH TO CAUSE PNEUMONIA."
Well, dang. With everything SLPs know about swallowing disorders, who would've thought that DYS-freakin'-PHAGIA - the actual disorder itself - wouldn't be one of the most significant clinical predictors of whether someone will develop aspiration pneumonia??
If that didn't turn my world upside-down, I don't know what will. It just goes to show that we still have so much left to learn. Hold your head up high, colleagues. We're in this together! Now excuse me while I go ice my brain cells...
Susan Langmore, PhD, CCC-SLP, BCS-S is an internationally recognized ASHA Fellow and currently serves as a Professor of Otolaryngology at Boston University School of Medicine and Clinical Professor at Boston University Sargent College. For more of Dr. Langmore's research/literature, please visit www.langmorefeesllc.com! She also hosts FEES courses in Boston, MA frequently throughout the year.
This blog post is part of a multi-part series where I summarize research articles that have completely changed my way of thinking and altered the way I approach dysphagia treatment/management. Please subscribe to my mailing list for new blog updates!