Relationship between the swallowing function and jaw-opening muscle strength in elderly cerebrovascular disease patients

目的：舌骨上筋群を含む開口筋は嚥下機能時の舌骨挙動に重要な役割を担うことから，本研究では，高齢脳血管疾患患者を対象に摂食嚥下機能と開口力の関係を明らかにすることを目的とした．方法：60歳以上の脳血管疾患入院患者の中から，嚥下障害と診断された者を対象とした．患者基本情報に関する情報はカルテから収集した．摂食嚥下機能は摂食嚥下障害臨床的重症度分類（以下DSS）を用いて評価を行うとともに，開口力は開口力測定器（TK2014）による測定を行った．開口力の性差はMann-WhitneyのU検定にて，DSSと開口力の相関関係はSpearmanの順位相関係数の検定にて解析した．また，DSSを正常範囲群と軽度障害群，誤嚥あり群の3群に分類し，Kruskal-Wallis検定にて開口力を比較した．結果：対象者は52名（男性25名，女性27名，平均年齢78.8±8.2歳），開口力の中央値は男性4.8 kg，女性3.0 kgであり，性差を認めた（p＝0.004）．全対象者および男性には年齢と開口力に有意な負の相関が認められた（r＝－0.362，p＝0.008；r＝－0.548，p＝0.005）．全てにおいてDSSと開口力には有意な正の相関関係を認めた（全対象者：r＝0.560，p＝0.000，男性：r＝0.636，女性：r＝0.587，ともにp＝0.001）．また，全対象者，男女ともに，正常範囲群に比べ，誤嚥あり群の開口力は有意に小さかった（全対象者：p＝0.006，男性：p＝0.024，女性：p＝0.015）．結論：高齢脳血管疾患患者において嚥下機能と開口力には有意な正の相関関係があり，誤嚥のある者は嚥下機能が正常範囲の者に比べ，開口力が低値であることが示唆された．Aim: In this study, we aimed to clarify the relationship between the swallowing function and the jaw-opening force after cerebrovascular disease. Methods: Elderly patients with a history of cerebrovascular disease with swallowing disability were enrolled in the present study. The swallowing function was evaluated using the Dysphagia Severity Scale (DSS), and the jaw-opening force was measured using Jaw-Opening Sthenometer (TK2014). The correlation between the DSS and jaw-opening force was analyzed using Spearman's correlation coefficient. Patients were also classified into three groups according to the DSS: normal, dysphagia, and aspiration groups. The jaw-opening forces of the three groups were compared using the Kruskal-Wallis test. Results: Fifty-two patients (27 women, average age 78.8±8.2 years) were recruited. A significant negative correlation was found between the patient age and jaw-opening force in all subjects (r=−0.362, p=0.008) as well as in men (r=−0.548, p=0.005). A significant positive correlation was found between the DSS and jaw-opening force in all subjects (r=0.560, p=0.000) and in both men (r=0.636, p=0.001) and women (r=0.587, p=0.001). The jaw-opening force of the aspiration group was significantly lower than that of the normal group in all subjects (p=0.006), as well as in men (p=0.024) and women (p=0.015). Conclusions: The DSS and jaw-opening force may have a significant positive correlation. Furthermore, it was shown that the jaw-opening force of the aspiration group was significantly lower than that of the normal-swallowing group