Effective mastication is important for physical and mental health, social well-being and nutritional intake in older adults. Recently, research has focused on oral function, using indicators such as masticatory performance (MP) and maximum bite force (MBF), rather specific oral diseases. Links between MP/MBF and systemic diseases (such as stroke, sarcopenia and anorexia), have been suggested, however, no solid conclusions have been drawn
The aim of this systematic review was to summarise the available evidence in the literature regarding associations between objectively assessed masticatory performance, chronic systemic diseases and physical function in older adults.
Methods
This systematic review was reported according to PRISMA statement guidelines and is registered in PROSPERO. Electronic searches were performed in three databases (PubMed/MEDLINE, Embase and CINAHL Plus) by two independent reviewers. Any disagreement was resolved through discussion with a third experienced researcher. A manual search was conducted on reference lists and a Google Scholar search was also performed. There were no restrictions on language or publication date. Methodological quality was independently evaluated by reviewers using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross Sectional Studies. The included studies were cross-sectional studies that reported the relationship between health conditions and MBF or MP by objective methods (and involved adults aged 50 years or older). Full text availability of studies were available. Studies without statistical analysis or that used subjective assessments to measure MP were excluded. Studies that were not cross-sectional and those with a sample size of less than 50 were also excluded.
Results
- 39 studies were included in this review (in total 21,736 participants were included)
- 21 studies were of strong quality and 18 studies were of moderate quality
- Associations between systemic disease and MP/MBF:
| Systemic disease | Association with MP/MBF |
| Stroke | Two studies concluded stroke patients had a significantly reduced MP compared to healthy individuals
Two studies found that MBF was not significantly reduced and one study reported a significant reduction in MBF in those with normal dentition (but not in denture wearers). All three studies showed no differences in MBF between the affected and non-affected sites |
| Sarcopenia | MP and MBF were lower in sarcopenic patients compared to healthy/presarcopenic patients (but logistic regression analysis revealed sarcopenia was a significant factor for MP only)
Good MP was negatively associated with possible sarcopenia |
| Amyotrophic lateral sclerosis (ALS)
|
MP was significantly reduced in patients with ALS compared to healthy patients
One study reported a significantly reduced MBF in ALS patients (but this was not reported in another study) |
| Chronic Obstructive Pulmonary Disease (COPD) | MP was significantly reduced in COPD patients compared to those without COPD |
| Carotid atherosclerosis | Maximum carotid intima-media thickness was higher in adults with lower MP |
| Diabetes mellitus | Two studies reported a negative association with MP and patients with diabetes mellitus. Two studies reported no significant association |
| Metabolic syndrome | No significant association with MP was reported |
| Dyspepsia | MP was significantly reduced in patients with non-ulcerative functional dyspepsia compared to patients without the condition |
| Dysphagia | Significant negative association with MP was reported |
| Anorexia | Significant negative association with MP was reported (this remained significant after adjusting confounding factors) |
| Parkinson’s disease | MBF was not significantly changed in Parkinson’s disease |
- Associations between physical function and MP/MBF:
- The overall trend of positive association of physical function with MP/MBF was universal
- Handgrip strength was the most commonly assessed physical function; seven out of nine studies reported a positive association between MP and handgrip strength
- Associations between oral conditions and MP/MBF:
- 19 studies investigated the association between oral conditions and MP/MBF
- Significant correlation between the number of remaining teeth and MP was found in nine studies
- Significant correlation between the number of remaining teeth and MBF was found in five studies
Conclusions
The authors concluded: –
The number of studies on the associations between objectively assessed masticatory performance and chronic systemic diseases and physical function in older adults is limited. Negative associations between masticatory function of older adults and presence of several systemic diseases have been reported in a number of studies while there are positive associations between masticatory function and some physical function indicators.
Comments
The observational cross-sectional studies used in this systematic review cannot draw causal relationships between MP/MBF and the variables. Further, well designed and conducted prospective studies would be needed to provide evidence for causality. The presence of impaired MP and reduced MBF can lead to a reduction in the intake of nutritious foods (such as protein rich foods), culminating in issues such as frailty and sarcopenia. Prevention and treatment of chronic diseases may improve masticatory function. As well as this, masticatory function may be improved through prosthodontic treatment (such as the placement of implants) and rehabilitation of masticatory muscles, following disease diagnosis (such as stroke).
Links
Primary paper
Other references
Dental Elf – 5th July 2013
The number, location and distribution of the teeth affect chewing ability in older adults
Photo credits
Photo by Mathias Konrath on Unsplash
