Prediction of Pneumonia in Acute Stroke Patients Using Tongue Pressure Measurements.

Masahiro Nakamori,Hirofumi Maruyama,Naohisa Hosomi,Tomohiko Ohshita,Kenichi Ishikawa,Masayasu Matsumoto,Eiji Imamura,Kazuhiro Tsuga,Shinichi Wakabayashi,Takeo Shishido,Mineka Yoshikawa,Yoshiaki Taniyama

doi:10.1371/journal.pone.0165837

Abstract

Swallowing dysfunction caused by stroke is a risk factor for aspiration pneumonia. Tongue pressure measurement is a simple and noninvasive method for evaluating swallowing dysfunction. We have hypothesized that low tongue pressure may be able to predict pneumonia occurrence in acute stroke patients. Tongue pressure was measured using balloon-type equipment in 220 acute stroke patients. The modified Mann Assessment of Swallowing Ability (MASA) score was evaluated independently on the same day. Tongue pressure was measured every week thereafter. An improvement in tongue pressure was observed within the first 2 weeks. Receiver operating curve analysis was performed to determine the ability of tongue pressure to predict modified MASA score <95, which suggests swallowing dysfunction. The optimal cutoff for tongue pressure was 21.6 kPa (χ2 = 45.82, p<0.001, sensitivity 95.9%, specificity 91.8%, area under the curve = 0.97). The tongue pressure was significantly lower in patients with pneumonia than in those without pneumonia. Using a Cox proportional hazard model for pneumonia onset with a cutoff tongue pressure value of 21.6 kPa and adjustment for age, sex, and National Institutes of Health Stroke Scale score at admission, the tongue pressure had additional predictive power for pneumonia onset (hazard ratio, 7.95; 95% confidence interval, 2.09 to 52.11; p = 0.0013). In the group with low tongue pressure, 27 of 95 patients showed improvement of tongue pressure within 2 weeks. Pneumonia occurred frequently in patients without improvement of tongue pressure, but not in patients with improvement (31/68 and 2/27, p<0.001). Tongue pressure is a sensitive indicator for predicting pneumonia occurrence in acute stroke patients.

Highlights

Swallowing dysfunction is a critical issue in stroke patients
Low tongue pressure contributes to inadequate closing, which increases the risk of aspiration during swallowing
We measured tongue pressure in constitutive acute stroke patients using balloontype equipment and found that it was significantly associated with the modified Mann Assessment of Swallowing Ability (MASA) score, which has been established as a reliable bedside assessment for detecting swallowing dysfunction [13]

Summary

Introduction

Swallowing dysfunction is a critical issue in stroke patients. Prevention of aspiration pneumonia and improvement of nutrition are associated with reduced duration of hospitalization and mortality [1,2,3]. Pneumonia rates have been found to be lower in hospitals using dysphagia screening protocols with appropriate interventions following the identification of patients at risk for aspiration in stroke patients [4]. Low tongue pressure impairs the control of the bolus, increases the amount of oral residue, which increases the risk of aspiration after swallowing. Low tongue pressure contributes to inadequate closing, which increases the risk of aspiration during swallowing. Several reports have established a relationship between tongue pressure and swallowing dysfunction. Tongue pressure has been associated with the presence of oro-pharyngeal residue using videofluoroscopic examination [9]. In a water-swallowing test, tongue pressure was found to be significantly lower in dysphagic patients than in non-dysphagic patients [10]. Using a non-invasive, easyto-use tongue pressure measurement tool is an advantage

Methods

Results

Conclusion