Abstract
This study clarifies the relationship among the morphological characteristics of the geniohyoid muscle, swallowing function, and olfactory function in community-dwelling older adults. The participants were 29 individuals aged 65 years or older (11 men, 18 women), living independently in Japan. Swallowing function was assessed using tongue pressure measurements, geniohyoid muscle thickness was evaluated using ultrasonography, and the Seirei Dysphagia Questionnaire was used. Olfactory function was evaluated using a card-type odor olfactory identification test. The qualitative sketch technique was used to categorize the muscle morphology into four groups: “uniform-straight,” “uniform-curved,” “thin-straight,” and “thin-curved.” Comparisons of the four groups revealed significant differences in muscle thickness (p = 0.007) and tongue pressure (p = 0.002), but no significant association with olfactory function (p =0.462). These results suggest that morphological characteristics of the geniohyoid muscle may be useful indicators for assessing muscle mass and swallowing function. Noninvasive ultrasonographic evaluation of the geniohyoid muscle morphology may contribute to the screening of older adults at risk of aspiration.
