A presentation I gave during an internship/Advanced Pharmacy Practice Experience (APPE) in ambulatory care at a dental clinic.

1. Paul Pasco, PharmD Candidate
ppasco@uthsc.edu
UTHSC College of Pharmacy
Wednesday, September 29, 2021
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2. Objectives
 Provide background information relevant to
understanding mild cognitive impairment and
dementia.
 Briefly review ubiquitous statistical measures for
evaluating evidence critically.
 Review new evidence about the influence of
tooth loss on developing mild cognitive
impairment or dementia.
 Describe the importance and implications of this
evidence for patient counseling in general
dentistry.
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3. Background
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4. What Is Mild Cognitive Impairment?
 Mild cognitive impairment (MCI)
 Change in baseline cognition, such as memory or thinking
 Due to their magnitude, these changes are NOT attributable to
age alone
 Not significant enough to be classified as dementia
 Symptoms do not interfere with activities of daily living
 May be attributed to:
 Depression, anxiety
 Vitamin B-12 deficiency
 Persons with MCI are more likely to develop dementia
 An irreversible pathological process causing MCI may already
be established
 May progress to dementia (10-15% of patients with MCI)
 Affects 5-20% of persons ≥ 65
4
Alzheimer's Society. What Is Mild Cognitive Impairment (MCI)? Alzheimers.org.uk; 2015:1-10. Accessed September 26, 2021.
https://www.alzheimers.org.uk/sites/default/files/pdf/factsheet_what_is_mild_cognitive_impairment_mci.pdf

5. How Does MCI Affect a Patient?
 MCI often presents with problems in:
 Memory
 Reasoning (thinking things through)
 Attention (easily distracted)
 Language (cannot find the right word)
 Visual depth perception (understanding 3D orientations of objects)
 MCI often affects oral health
 Elderly persons with MCI are often dependent on others for oral hygiene
 Oral hygiene is more likely to be inadequate
 Increased risk of periodontal disease and tooth loss
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Alzheimer's Society. What Is Mild Cognitive Impairment (MCI)? Alzheimers.org.uk; 2015:1-10. Accessed September 26, 2021.
https://www.alzheimers.org.uk/sites/default/files/pdf/factsheet_what_is_mild_cognitive_impairment_mci.pdf

6. What is Dementia?
 Dementia is a change in cognition that is severe
enough in magnitude to interfere with ADLs
 A group of diseases (NOT a specific disease) that
affect cognition
 Alzheimer’s dementia is the most common type
 Other types include vascular dementia, Lewy body
dementia, Korsakoff syndrome, and others
 Risk factors
 Genetic predisposition
 Depression
 Hearing loss
 Loss of teeth
 Atherosclerotic cardiovascular disease (ASCVD)
 Many others
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Alzheimer's Association. Dementia vs. Alzheimer’s Disease: What Is the Difference? Alzheimer’s Association. Published 2021. Accessed September 26, 2021. https://www.alz.org/alzheimers-dementia/difference-between-
dementia-and-alzheimer-s

7. Statistical Measures
 Relative risk (RR)
 Also called a risk ratio
 Compares the risk of some event related to health in 2 groups
 These two groups are different in a key characteristic
 Demographics (e.g., male vs. female)
 Exposure to a variable (e.g., one group that has lost teeth versus a second group that has
not)
 Exposed (experimental/primary interest) group
 Unexposed (control/comparison) group
 Confidence interval (CI)
 A range where the true value for the RR lies at the predefined CI (e.g., the CI
contains the true value for the RR 95% of the time)
 Think of it as a way to represent uncertainty of a specific value
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Centers for Disease Control and Prevention. Principles of Epidemiology in Public Health Practice, Third Edition: An Introduction to Applied Epidemiology and Biostatistics. Centers for Disease Control and Prevention.
Published May 18, 2012. Accessed September 26, 2021. https://www.cdc.gov/csels/dsepd/ss1978/lesson3/section5.html
United States Census Bureau. A Basic Explanation of Confidence Intervals. Census.gov. Published May 4, 2017. Accessed September 26, 2021. https://www.census.gov/programs-surveys/saipe/guidance/confidence-
intervals.html

8. Overview of the Literature
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9. Summary of the Literature
 Meta-analysis of 14 longitudinal studies (8 used in dose-response
analysis)
 Yielded a linear dose-response relationship
 Increase in # teeth lost = increase in risk of poor cognition
 These results occurred even after controlling for confounding variables
 N = 34,074 persons
 4689 cases with decreased cognitive function were identified
 Persons with tooth loss had a relative risk of 1.48 for developing MCI
 Tooth loss = 48% higher risk of developing MCI
 95% confidence interval (CI) [1.18-1.87]
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10. Summary of the Literature (cont.)
 Persons with tooth loss had a relative risk (RR) of 1.28
 Tooth loss = 28% higher risk of developing dementia
 95% CI [1.09-1.49]
 Persons using dentures had a RR of 1.10
 Tooth loss with replacement by dentures = 10% higher risk of cognitive dysfunction
(but NOT STATISTICALLY SIGNIFICANT)
 95% CI [0.90-1.11]
 The loss of one additional tooth was associated with:
 0.014 (1.4%) increase in the RR for mild cognitive impairment (MCI)
 0.011 (1.1%) increase in the RR for dementia
 Edentulous (toothless) patients had a:
 RR of 1.54 (54% increase) for MCI
 RR of 1.40 (40% increase) for dementia
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11. Appraisal of the Evidence
Correlation ≠ causation
 Chicken or the egg?
 Some evidence for causation here due to quality of
evidence and types of studies used
 Metanalyses are credible evidence, but nothing is
without limitations
 RCT would be ideal but highly unethical
 Some tooth loss was self-reported, but
changes in this with subgroup analysis
were not statistically significant
 Further evaluation is required
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Central Michigan University. Evidence-Based Medicine: Resources by Levels of Evidence. Cmich.edu. Published August 16, 2021. Accessed September 26, 2021. https://libguides.cmich.edu/cmed/ebm/pyramid

12. Conclusion
Based on the presently available evidence,
tooth loss has an independent, positive, and
dose-responsive relationship with both mild
cognitive impairment and dementia.
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13. Analysis: Why Is this Important?
 Credible, moderate-quality evidence that tooth loss
is positively associated with impaired cognition of
variable severity, even with one tooth lost
 Opportunities for early counseling and/or
intervention in the outpatient setting
 Dental hygienists
 Dentists
 Opportunities to highlight the importance of
procedures or devices for restoration of function
 Dental implants
 Dentures
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14. Questions?
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15. References
1. Alzheimer's Society. What Is Mild Cognitive Impairment (MCI)? Alzheimers.org.uk; 2015:1-10. Accessed September 26, 2021.
https://www.alzheimers.org.uk/sites/default/files/pdf/factsheet_what_is_mild_cognitive_impairment_mci.pdf
2. Alzheimer's Association. Dementia vs. Alzheimer’s Disease: What Is the Difference? Alzheimer’s Association. Published 2021. Accessed
September 26, 2021. https://www.alz.org/alzheimers-dementia/difference-between-dementia-and-alzheimer-s
3. Central Michigan University. Evidence-Based Medicine: Resources by Levels of Evidence. Cmich.edu. Published August 16, 2021.
Accessed September 26, 2021. https://libguides.cmich.edu/cmed/ebm/pyramid
4. Centers for Disease Control and Prevention. Principles of Epidemiology in Public Health Practice, Third Edition: An Introduction to
Applied Epidemiology and Biostatistics. Centers for Disease Control and Prevention. Published May 18, 2012. Accessed September 26,
2021. https://www.cdc.gov/csels/dsepd/ss1978/lesson3/section5.html
5. United States Census Bureau. A Basic Explanation of Confidence Intervals. Census.gov. Published May 4, 2017. Accessed September 26,
2021. https://www.census.gov/programs-surveys/saipe/guidance/confidence-intervals.html
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16. Paul Pasco, PharmD Candidate
ppasco@uthsc.edu
UTHSC College of Pharmacy
Wednesday, September 29, 2021
16