Abstract
Objective
To investigate the prospective associations between oral health and progression of physical frailty in older adults.
Design
Prospective analysis.
Setting and Participants
Data are from the British Regional Heart Study (BRHS) comprising 2137 men aged 71 to 92 years from 24 British towns and the Health, Aging, and Body Composition (HABC) Study of 3075 men and women aged 70 to 79 years.
Methods
Oral health markers included denture use, tooth count, periodontal disease, self-rated oral health, dry mouth, and perceived difficulty eating. Physical frailty progression after ∼8 years follow-up was determined based on 2 scoring tools: the Fried frailty phenotype (for physical frailty) and the Gill index (for severe frailty). Logistic regression models were conducted to examine the associations between oral health markers and progression to frailty and severe frailty, adjusted for sociodemographic, behavioral, and health-related factors.
Results
After full adjustment, progression to frailty was associated with dentition [per each additional tooth, odds ratio (OR) 0.97; 95% CI: 0.95–1.00], <21 teeth with (OR 1.74; 95% CI: 1.02–2.96) or without denture use (OR 2.45; 95% CI 1.15–5.21), and symptoms of dry mouth (OR ≥1.8; 95% CI ≥ 1.06–3.10) in the BRHS cohort. In the HABC Study, progression to frailty was associated with dry mouth (OR 2.62; 95% CI 1.05–6.55), self-reported difficulty eating (OR 2.12; 95% CI 1.28–3.50) and ≥2 cumulative oral health problems (OR 2.29; 95% CI 1.17–4.50). Progression to severe frailty was associated with edentulism (OR 4.44; 95% CI 1.39–14.15) and <21 teeth without dentures after full adjustment.
Conclusions and Implications
These findings indicate that oral health problems, particularly tooth loss and dry mouth, in older adults are associated with progression to frailty in later life. Additional research is needed to determine if interventions aimed at maintaining (or improving) oral health can contribute to reducing the risk, and worsening, of physical frailty in older adults.
Worldwide there has been a rapid demographic transition resulting in an unprecedented growth of the aging population, with 16% of the population predicted to be 65 years or older by 2050.
1UN. World Population Ageing 2020 Highlights: Living arrangements of older persons.
Together with increased life expectancy, this has resulted in an important public health challenge: to maintain independent living, specifically by delaying or preventing frailty in older adults.
2- Cesari M.
- Prince M.
- Thiyagarajan J.A.
- et al.
Frailty: an emerging public health priority.
,3- Hoogendijk E.O.
- Afilalo J.
- Ensrud K.E.
- et al.
Frailty: implications for clinical practice and public health.
Frailty is a complex age-related syndrome that represents a dynamic progression from robustness to functional decline resulting in an elevated risk of adverse health outcomes, such as falls, disability, hospitalization, institutionalization, and mortality, and is a major health concern for older people, their families, and their carers.
4- Fried L.P.
- Tangen C.M.
- Walston J.
- et al.
Frailty in older adults: evidence for a phenotype.
,5- Lang P.O.
- Michel J.P.
- Zekry D.
Frailty syndrome: a transitional state in a dynamic process.
A recent review of studies has shown that objective and subjective markers of poor oral health are associated with frailty in older adults.
6- Slashcheva L.D.
- Karjalahti E.
- Hassett L.C.
- et al.
A systematic review and gap analysis of frailty and oral health characteristics in older adults: a call for clinical translation.
In addition, we have shown that oral health markers are associated with self-reported physical frailty in the British Regional Heart Study (BRHS).
7- Ramsay S.E.
- Papachristou E.
- Watt R.G.
- et al.
Influence of poor oral health on physical frailty: a population-based cohort study of older british men.
There are reasons to expect that oral health may be related to frailty, given that oral health is implicated in microbiome dysbiosis, inflammatory/immunological status, and nutritional changes.
8- Kotronia E.
- Brown H.
- Papacosta A.O.
- et al.
Poor oral health and the association with diet quality and intake in older people in two studies in the UK and USA.
, 9- Konkel J.E.
- O'Boyle C.
- Krishnan S.
Distal consequences of oral inflammation.
, 10The oralome and its dysbiosis: new insights into oral microbiome-host interactions.
However, the aforementioned review demonstrates a paucity of longitudinal studies and few studies have examined whether oral health markers are associated with progression, or worsening, of frailty in older adults.
6- Slashcheva L.D.
- Karjalahti E.
- Hassett L.C.
- et al.
A systematic review and gap analysis of frailty and oral health characteristics in older adults: a call for clinical translation.
In one study, Horibe and colleagues
11- Horibe Y.
- Ueda T.
- Watanabe Y.
- et al.
A 2-year longitudinal study of the relationship between masticatory function and progression to frailty or pre-frailty among community-dwelling Japanese aged 65 and older.
demonstrated an association between oral health and frailty progression, but they had limited oral health markers (including objective and subjective chewing ability) and, in common with other studies in this area, had a relatively short follow-up period. These limitations in the evidence base highlight the need for additional well-designed longitudinal studies, with longer follow-up periods and with comprehensive assessments of oral health markers, to examine the prospective associations between oral health with frailty in older adults.
Furthermore, most studies use the Fried frailty phenotype to characterize physical frailty.
6- Slashcheva L.D.
- Karjalahti E.
- Hassett L.C.
- et al.
A systematic review and gap analysis of frailty and oral health characteristics in older adults: a call for clinical translation.
Although the frailty phenotype has been used widely in epidemiological studies and is important for comparison with prior work,
12- Bouillon K.
- Kivimaki M.
- Hamer M.
- et al.
Measures of frailty in population-based studies: an overview.
there is no universal consensus in the operational criteria used to define physical frailty. An alternative tool is the Gill index, which characterizes severe frailty based on a composite measure of chair-stand and walking speed tests.
13- Gill T.M.
- Baker D.I.
- Gottschalk M.
- et al.
A program to prevent functional decline in physically frail, elderly persons who live at home.
The Gill index has been used predominantly in the Health Aging and Body Composition (HABC) Study to characterize physical frailty and is more representative of functional measures that have been strongly associated with the progression of frailty to disability.
14- Khan H.
- Kalogeropoulos A.P.
- Georgiopoulou V.V.
- et al.
Frailty and risk for heart failure in older adults: the health, aging, and body composition study.
, 15- Peterson M.J.
- Giuliani C.
- Morey M.C.
- et al.
Physical activity as a preventative factor for frailty: the health, aging, and body composition study.
, 16- Kamil R.J.
- Betz J.
- Powers B.B.
- et al.
Association of hearing impairment with incident frailty and falls in older adults.
The HABC Study has detailed information on oral health measures that are similar to the BRHS. Therefore, we investigated whether oral health is prospectively associated with progression of frailty as measured by 2 different measures of frailty (the Fried frailty phenotype and the Gill index) in 2 cohorts of older adults in the United States and United Kingdom.
Discussion
The aim of the current study was to investigate the prospective associations between oral health and progression of physical frailty in older adults. The main finding was that there are associations between markers of poor oral health and frailty progression, as measured by the frailty phenotype in 2 cohorts of older adults from the United Kingdom and the United States, that persisted even after controlling for sociodemographic and behavioral factors, comorbidities, and IL-6 concentration (a biomarker of systemic inflammation). In contrast, the associations between poor oral health and progression to severe frailty (Gill index) were mostly attenuated in the adjusted models, apart from edentulism and <21 teeth without the use of dentures which remained significant in the HABC Study only. The findings of the current study add to a growing body of evidence that indicate that maintenance of oral health may be important in preventing frailty progression in older adults.
6- Slashcheva L.D.
- Karjalahti E.
- Hassett L.C.
- et al.
A systematic review and gap analysis of frailty and oral health characteristics in older adults: a call for clinical translation.
In the BRHS, compared with those with functional dentition, fewer remaining natural teeth with or without denture use was associated with frailty progression. In addition, each additional natural tooth retained was associated with a reduced risk of frailty, in agreement with a previous study.
26- Castrejón-Pérez R.C.
- Jiménez-Corona A.
- Bernabé E.
- et al.
Oral Disease and 3-Year Incidence of Frailty in Mexican Older Adults.
In the HABC Study those with <21 teeth and no dentures had higher odds of progressing to severe frailty, but not those who wore dentures. The differences in the causes underlying tooth loss and/or in management of tooth loss and quality of dental prothesis used in the UK and USA study populations might also be responsible for these observed differences in the two studies. Tooth loss has been shown to affect masticatory function, nutritional choices, and diet quality that might increase risk of adverse outcomes, such as frailty.
8- Kotronia E.
- Brown H.
- Papacosta A.O.
- et al.
Poor oral health and the association with diet quality and intake in older people in two studies in the UK and USA.
,27- Marcenes W.
- Steele J.G.
- Sheiham A.
- et al.
The relationship between dental status, food selection, nutrient intake, nutritional status, and body mass index in older people.
In the current study, self-reported difficulty eating was associated with progression to severe frailty in the BRHS and to frailty in the HABC Study, but these associations did not remain significant after full adjustment in the BRHS. It is important to acknowledge that the current study did not take in to account the severity of difficulty eating and therefore this might not have been the most reliable measure of detecting changes in nutritional intake. In a previous study, frailty was only associated with higher level of difficulty eating a number of foods.
28- Albani V.
- Nishio K.
- Ito T.
- et al.
Associations of poor oral health with frailty and physical functioning in the oldest old: results from two studies in England and Japan.
The difficulty eating pathway has been supported by a previous study, in that non–denture users with <20 teeth had higher odds for low grip strength, a component of frailty, and nutritional intake indirectly explained approximately a third of this relationship.
29Association between number of teeth, use of dentures and musculoskeletal frailty among older adults.
Although the results from the BRHS, in line with others,
30- Zhang Y.
- Ge M.
- Zhao W.
- et al.
Association between number of teeth, denture use and frailty: findings from the west China health and aging trend study.
suggest that use of dentures might not completely attenuate this relationship, it may mean that dentures do not fully restore oral function. Denture types (for example, full or partial) represent different challenges for restoration and functionality in older people and should be investigated in future studies.
In both cohorts, self-reported dry mouth was associated with progression to frailty, despite different methods of assessment. Dry mouth is often a consequence of medication for chronic age-related diseases,
31- Tan E.C.
- Lexomboon D.
- Sandborgh-Englund G.
- et al.
Medications that cause dry mouth as an adverse effect in older people: a systematic review and metaanalysis.
adversely affecting taste, appetite and nutrition intake, and also causing ulceration, dental diseases, and systemic inflammation that might be related to frailty.
32- Han P.
- Suarez-Durall P.
- Mulligan R.
Dry mouth: a critical topic for older adult patients.
, 33- Proctor D.M.
- Seiler C.
- Burns A.R.
- et al.
Spatial patterns of dental disease in patients with low salivary flow.
, 34The association of xerostomia and inadequate intake in older adults.
, 35- Marcos-Pérez D.
- Sánchez-Flores M.
- Proietti S.
- et al.
Association of inflammatory mediators with frailty status in older adults: results from a systematic review and meta-analysis.
However, it should be acknowledged that dry mouth and frailty may have occurred simultaneously as a result of other age-related comorbidities, medications, and psychological factors, making the relationship complex. The associations in the BRHS remained significant even after controlling for medications with xerostomia (dry mouth) as a recognized side effect, chronic diseases, diet, and IL-6, adding confidence to these findings. The association with dry mouth remained significant in the HABC Study also after controlling for sociodemographic and behavioural factors, but was attenuated on adjustment for health factors and IL-6, demonstrating these complexities. In addition to the adverse consequences of poor nutritional status, inflammation represents another potential underlying pathway that might mediate the relationship between poor oral health and risk of frailty by affecting organs and tissues distant to the oral cavity and decreasing functional reserve capacities.
26- Castrejón-Pérez R.C.
- Jiménez-Corona A.
- Bernabé E.
- et al.
Oral Disease and 3-Year Incidence of Frailty in Mexican Older Adults.
, 36- Álvarez-Satta M.
- Berna-Erro A.
- Carrasco-Garcia E.
- et al.
Relevance of oxidative stress and inflammation in frailty based on human studies and mouse models.
Low-grade chronic inflammation can exacerbate muscle wasting, by stimulating muscle catabolism and suppressing protein synthesis leading to reduced physical function and frailty.
35- Marcos-Pérez D.
- Sánchez-Flores M.
- Proietti S.
- et al.
Association of inflammatory mediators with frailty status in older adults: results from a systematic review and meta-analysis.
, 37- Pan L.
- Xie W.
- Fu X.
- et al.
Inflammation and sarcopenia: a focus on circulating inflammatory cytokines.
, 38- Clark D.
- Kotronia E.
- Ramsay S.E.
Frailty, aging, and periodontal disease: basic biologic considerations.
Nevertheless, these data are in line with previous studies and highlight the potential role of dry mouth as an indicator of frailty in later life.
7- Ramsay S.E.
- Papachristou E.
- Watt R.G.
- et al.
Influence of poor oral health on physical frailty: a population-based cohort study of older british men.
,39- Ohara Y.
- Kawai H.
- Shirobe M.
- et al.
Association between dry mouth and physical frailty among community-dwelling older adults in Japan: the Otassha Study.
In addition, we confirmed previous associations
7- Ramsay S.E.
- Papachristou E.
- Watt R.G.
- et al.
Influence of poor oral health on physical frailty: a population-based cohort study of older british men.
that composite or cumulative oral health problems, including dry mouth, were associated with frailty progression in the HABC Study. Consistent with this, in a recent study in older Canadian adults, number of oral health problems was associated with the frailty index, suggesting worsening of frailty with each additional adverse oral health factor.
40- Bassim C.
- Mayhew A.J.
- Ma J.
- et al.
Oral health, diet, and frailty at baseline of the Canadian longitudinal study on aging.
Although the link between periodontal disease and frailty has been reported,
26- Castrejón-Pérez R.C.
- Jiménez-Corona A.
- Bernabé E.
- et al.
Oral Disease and 3-Year Incidence of Frailty in Mexican Older Adults.
this was not observed in the current study. A smaller sample (only those with natural teeth) for this analysis may have led to lack of power to detect an association between periodontal status and progression of frailty. Furthermore, the limited associations between severe frailty (Gill index) and oral health might be as a result of the frailty phenotype comprising of more domains (including lower and upper body physical performance, weight loss, exhaustion, and physical activity) increasing the likelihood that the phenotype will detect frailty,
41- Kim H.
- Higgins P.A.
- Canaday D.H.
- et al.
Frailty assessment in the geriatric outpatient clinic.
and thus increase the power to establish associations. It has been well documented that poor oral health can negatively affect nutritional intake,
42- Sheiham A.
- Steele J.
- Marcenes W.
- et al.
The relationship among dental status, nutrient intake, and nutritional status in older people.
and has shown to be a strong predictor of weight loss, a component of the frailty phenotype.
43- Ritchie C.S.
- Joshipura K.
- Silliman R.A.
- et al.
Oral health problems and significant weight loss among community-dwelling older adults.
In another study, people with missing teeth were more likely to have impaired mastication, which was associated with fatigue, low physical activity, slow gait speed, and overall frailty.
11- Horibe Y.
- Ueda T.
- Watanabe Y.
- et al.
A 2-year longitudinal study of the relationship between masticatory function and progression to frailty or pre-frailty among community-dwelling Japanese aged 65 and older.
Therefore, oral health might differentially affect other frailty-related domains rather just than lower body physical performance (the focus of the Gill index). Moreover, there was a lower proportion of those who worsened to severe frailty at follow-up according to the Gill index in both studies, and to either frailty score in the HABC Study, factors that may help explain the different associations observed between the 2 scores and studies.
This study has several strengths, including the relatively large samples of 2 cohorts of community-dwelling older adults with detailed information on oral health, use of 2 measures of physical frailty, and follow-up for a long period (∼8 years). In addition, we included several important covariates in the models, including markers of diet quality and inflammation that had not previously been included in previous studies of this nature. Nonetheless, we cannot exclude the possibility of residual confounding, which needs careful consideration. In addition, the generalizability of findings could be limited due to studies comprising White men (BRHS) and White and African American men and women from only 2 areas in the United States (HABC Study). Moreover, because both frailty and oral health status are dynamic, not static, processes, the temporal and bidirectional relationship should be the focus of future longitudinal studies to help strengthen evidence for potential causal links between oral health and frailty. Furthermore, the frailty measures we have used did not take account of cognitive decline or psycho-social aspects.
Article info
Publication history
Published online: December 27, 2022
Publication stage
In Press Corrected ProofFootnotes
The research was supported by core funding from the British Heart Foundation [since 2009 this has included both programme grants (RG/08/013/25942, RG/13/16/30528, RG/19/4/34452) and project grants (PG/13/86/30546 and PG/13/41/30304)] and National Institute on Aging (NIA) contracts #N01-AG-6–2101; N01-AG-6–2103; N01-AG-6–2106; NIA grant (R01-AG028050); NINR grant (R01-NR012459). Funding has also been received from the Medical Research Council (G1002391) Dunhill Medical Trust (R592_0717, R592_0515 and R396_1114) and National Institute for Health Research/NIHR School for Primary Care Research (FR3 – 80, FR5- 166, FR9 -533690, FR10- 281 and 13_CM08) and US NIH/NIDCR grant R03 DE028505–02.
The authors declare no conflicts of interest.
Copyright
© 2022 The Authors. Published by Elsevier Inc.