Relationship between Tongue Pressure and Salivary Bacteria in the Older Adults Requiring Long-Term Care

Abstract

<b><i>Introduction:</i></b> Aspiration pneumonia, an important issue for the older adults, is caused by an increase in pathogenic microorganisms in the saliva, aspiration, and weakened host immunity. Recently, decreased tongue pressure has been reported to be associated with dysphagia. This study aimed to investigate the relationship between decreased tongue pressure and the number of bacteria in the saliva of the older adults requiring long-term care. <b><i>Methods:</i></b> This cross-sectional study involved 95 older adults requiring long-term care in a facility or at home, eating orally, and who could understand the instructions for measuring tongue pressure. Sex, age, slowness, weakness, shrinking, exhaustion, low activity, number of teeth, functional teeth unit, denture use, oral hygiene, tongue coating index, dry mouth, tongue pressure, and number of bacteria in the saliva were examined. Bacterial counts were analyzed by real-time PCR for total bacteria, total streptococci, methicillin-resistant <i>Staphylococcus aureus</i>, <i>Streptococcus pneumoniae</i>, <i>Pseudomonas aeruginosa</i>, <i>Porphyromonas gingivalis</i>, and <i>Candida albicans</i>. <b><i>Results:</i></b> Multiple regression analysis showed that poor oral hygiene and decreased tongue pressure were independent risk factors for increased bacteria in the saliva. Decreased tongue pressure is significantly correlated with an increased number of total bacteria and the presence of <i>P. gingivalis</i>. <b><i>Discussion/Conclusion:</i></b> Our results suggest that tongue pressure not only maintains the swallowing function but also prevents the increase of bacteria in the saliva of older adults requiring long-term care.

Brushing Methods for Patients Unable to Use a Mouthwash: A Preliminary Study of the Effects of Moisturizing Gel and Povidone-Iodine in Healthy Volunteers

“…It is important to reduce the number of bacteria in saliva, prevent aspiration, and improve the general condition of the patient to prevent aspiration pneumonia. Therefore, the importance of oral care for older adults and postoperative patients is widely reported [1][2][3][4][13][14][15][16][17]. Additionally, VAP in endotracheally intubated patients is directly related to survival outcomes and is a serious post-operative complication [6].…”

“…The human oral cavity contains many microorganisms (such as bacteria and fungi) that are controlled by oral cleansing methods such as oral intake, saliva secretion, and swallowing. However, bacterial counts are markedly increased in older adults with decreased oral functions, such as in cases of tongue pressure [ 1 ], fasting, or tube feeding [ 2 ], and in intubated patients [ 3 , 4 ]. The most effective method to reduce the oral bacterial count is rinsing the mouth, which is not possible in patients with decreased swallowing function or under intubation [ 5 ].…”

Effect of oral function and postoperative eating patterns on salivary bacterial counts in gastrointestinal tract surgery patients: A preliminary study

“… 10 A significant association has been reported between decreased tongue pressure and increased salivary bacterial counts in institutionalized elderly patients requiring long-term care. 11 While these studies have indicated an association between poor oral function and increased salivary bacterial counts in the elderly, there have been no similar reports on perioperative patients. Identifying factors associated with increased salivary bacterial counts in perioperative patients would help determine which patients require focused oral care.…”

“…Saliva was collected from the bottom of the mouth using a filter paper, according to the method described by Funahara. 11 The following variables were also collected from medical records: age, sex, primary disease, body mass index (BMI), serum albumin level, and operation time. Salivary bacterial counts were measured by real-time polymerase chain reaction (PCR; DNA extraction technique, primer, artificial DNA, and reaction conditions used were as previously reported by Tsuda.…”

“…Our research group found that tongue pressure decreases as the number of functional teeth decreases even in healthy elderly people, and that low tongue pressure increases the number of bacteria in saliva. 10 , 11 Moreover, elderly patients who require nursing care and have decreased tongue pressure are more prone to aspiration pneumonia and have a higher mortality rate due to aspiration pneumonia. 12 Decreased tongue pressure in the elderly is associated with systemic sarcopenia.…”