Your Missing Teeth Could Predict Hospital Stays: Groundbreaking Canadian Research Reveals

A landmark Statistics Canada study has uncovered a striking connection between tooth loss and hospitalization risk: Canadians missing five or more natural teeth face a 76% higher risk of hospitalization for any cause—and an alarming 120% increased risk for circulatory system diseases.

The First of Its Kind in Canada

This groundbreaking research represents the first Canadian study to provide time-to-event evidence linking clinically measured oral health with hospitalization and mortality outcomes. The findings add compelling Canadian data to the growing global body of evidence connecting oral health with systemic health conditions.

"This study is the first to provide time-to-event evidence on clinically measured oral health and its association with hospitalisation and mortality outcomes in Canada," wrote the four-member research team from Statistics Canada.

The Study Design

Research Team:

• Xue Feng Hu, Statistics Canada
• Mohammad Moharrami, Statistics Canada and University of Toronto Faculty of Dentistry
• Janine Clarke, Statistics Canada
• Kellie Murphy, Statistics Canada

Data Sources: The analysis utilized comprehensive national health data:

1. Canadian Health Measures Survey (CHMS) Cycle 1 (2007-2009)

   • Direct clinical tooth counts performed by trained professionals
   • Not self-reported data

2. Canadian Vital Statistics – Death Database

   • Linked mortality data through 2019

3. Discharge Abstract Database

   • Hospital admission records through 2019

Study Population:

• 3,454 participants in mortality linkage analysis
• 2,252 participants in hospitalization linkage analysis
• Ages 20 to 79 years
• Average follow-up period: 11 years
• Population-based sample representing diverse demographics

The Striking Findings

Using hazard ratios—a statistical measure that estimates how much more likely an event is to occur in one group compared to another over time—researchers quantified the relationship between tooth loss and health outcomes.

Key Results After Adjusting for Confounding Factors:

Adults missing five or more teeth showed:

All-Cause Hospitalization:

• Hazard Ratio (HR): 1.76
• 76% increased risk compared to those with fewer missing teeth
• Results remained statistically significant after adjusting for age, sex, smoking status, and diabetes

Circulatory System Diseases:

• Hazard Ratio (HR): 2.20
• 120% increased risk of hospitalization for cardiovascular and circulatory conditions
• More than doubled the risk compared to those with better oral health

Understanding the Statistics:

The 95% confidence intervals for these findings were narrow, indicating high precision and certainty in the results. This means researchers can be very confident that the true relationship between tooth loss and hospitalization risk falls within this range.

The Current State of Oral Health in Canada

Data from the Canadian Health Measures Survey revealed the distribution of tooth loss among Canadian adults:

Tooth Loss Distribution (2007-2009):

• 49.6% had no missing crowned teeth (completely intact dentition)
• 26.3% had 1-4 missing crowns (mild tooth loss)
• 17.5% had 5+ missing crowns (moderate to severe tooth loss)
• 6.4% were edentulous (complete tooth loss)

A Positive Trend: Declining Edentulism

While the hospitalization risks are concerning, there's encouraging news about improving oral health trends in Canada:

Edentulism Rates Over Time:

• 1970-72: 23.6% of Canadian adults completely edentulous
• 2007-09: 6.4% edentulous (73% reduction)
• 2023-24: 4.4% edentulous (continuing improvement)

This remarkable decline—from nearly one in four adults to fewer than one in twenty—represents a major public health success, likely reflecting improved dental care access, fluoridation, preventive education, and changing attitudes toward oral health.

Why Missing Teeth Matter: The Biological Connection

The research team described missing teeth as a "cumulative indicator of lifelong oral-health deterioration" that may function as a "simple, non-invasive marker" of broader health risk or healthcare service utilization.

Potential Mechanisms:

While the study establishes association rather than causation, several biological pathways may explain the connection:

1. Chronic Inflammation:

• Periodontal disease (often preceding tooth loss) generates chronic inflammation
• Inflammatory mediators enter bloodstream
• Contributes to atherosclerosis and cardiovascular disease

2. Bacterial Translocation:

• Oral bacteria can enter bloodstream through diseased gums
• May contribute to endocarditis, arterial plaque formation
• Systemic spread of oral pathogens

3. Nutritional Compromise:

• Missing teeth impair chewing ability
• Reduced consumption of nutritious foods (fruits, vegetables, whole grains)
• Nutritional deficiencies affect overall health

4. Shared Risk Factors:

• Smoking affects both oral and systemic health
• Diabetes increases periodontal disease risk and complications
• Socioeconomic factors impact both dental care access and general health

5. Indicator of Healthcare Engagement:

• Tooth loss may signal limited preventive healthcare utilization
• Reflects barriers to care access
• May indicate lower health literacy or resources

No Gender Differences, But Age Matters

The study found no major differences in tooth loss patterns between men and women, challenging some previous assumptions about gender-based oral health disparities. However, tooth loss showed progressive increase with age—an expected finding given the cumulative nature of oral disease and dental extraction over a lifetime.

The Circulatory System Connection

The particularly strong association between tooth loss and circulatory system diseases (120% increased risk) aligns with extensive research linking oral health to cardiovascular conditions.

Circulatory Conditions May Include:

• Coronary artery disease
• Heart attack (myocardial infarction)
• Stroke
• Peripheral artery disease
• Heart failure
• Hypertension complications
• Atherosclerosis

This finding adds to growing evidence that oral health should be considered an integral component of cardiovascular risk assessment and prevention strategies.

Clinical Implications for Dental Professionals

This research has important implications for how dental professionals approach patient care:

1. Holistic Risk Assessment:

• Consider tooth loss as indicator of systemic health risk
• Screen patients with significant tooth loss for cardiovascular risk factors
• Communicate with medical providers about oral health status

2. Prevention Emphasis:

• Prioritize tooth preservation strategies
• Aggressive periodontal disease management
• Early intervention for at-risk teeth

3. Patient Education:

• Discuss connections between oral and systemic health
• Frame dental care as preventive medicine
• Motivate patients with broader health implications

4. Interdisciplinary Collaboration:

• Coordinate care with physicians, especially for high-risk patients
• Share information about significant oral disease
• Consider oral health in hospital discharge planning

Implications for Healthcare Policy

The findings support several policy considerations:

1. Integrated Healthcare Models:

• Include oral health in primary care settings
• Train medical professionals to recognize oral disease
• Facilitate referrals between medical and dental providers

2. Coverage and Access:

• Expand dental coverage, particularly for at-risk populations
• Address barriers to preventive dental care
• Consider oral health in chronic disease management programs

3. Public Health Initiatives:

• Maintain and expand community water fluoridation
• Support school-based dental programs
• Target oral health education to high-risk groups

4. Research Funding:

• Support investigations into oral-systemic health connections
• Develop intervention trials testing whether improved oral health reduces hospitalization

Study Limitations and Future Directions

The authors transparently acknowledged several limitations:

Geographic Coverage:

• Sample excluded Quebec and Atlantic provinces
• Limits national representativeness
• Regional variations may exist

Follow-Up Duration:

• Average 11-year follow-up may be insufficient for certain mortality analyses
• Absence of statistically significant adjusted mortality link shouldn't be interpreted as proof of no association
• Longer follow-up may reveal mortality relationships

Causation vs. Association:

• Study establishes association, not direct causation
• Tooth loss treated as indicator rather than direct causal factor
• Unmeasured confounders may partially explain relationships

Unmeasured Variables: The authors noted that other factors not captured in the analysis could help explain the association:

• Detailed nutritional status
• Severity and extent of periodontal disease
• Socioeconomic indicators beyond basic demographics
• Quality of dental care received
• Oral hygiene behaviors
• Access to healthcare services

Future Research Recommendations:

The research team suggested sophisticated analytical approaches for future studies:

• Directed acyclic graphs (DAGs): To map potential causal pathways
• Path analysis: To assess direct and indirect effects
• Mediation analysis: To identify mechanisms linking tooth loss to outcomes
• Moderation analysis: To identify factors that strengthen or weaken relationships

What This Means for Patients

Practical Takeaways:

✓ Maintain your natural teeth through good oral hygiene and regular dental care

✓ Address dental problems promptly before they lead to tooth loss

✓ Treat periodontal disease aggressively as it's often the precursor to tooth loss

✓ Don't ignore missing teeth as they may signal broader health risks

✓ Inform your physician about significant oral health problems

✓ Consider tooth replacement options (implants, bridges, dentures) to maintain function

✓ Recognize oral health as integral to overall health maintenance

The Broader Context: Oral-Systemic Health Research

This study joins a growing body of evidence connecting oral health to systemic conditions:

Recent Related Findings:

• Gum disease and cavities linked to higher stroke risk
• Oral bacteria potentially contributing to heart attacks
• Possible connections between oral bacteria and Parkinson's disease
• Periodontal disease associations with diabetes complications
• Links between oral health and pregnancy outcomes
• Potential connections to respiratory infections

This accumulating evidence suggests that the mouth-body connection is more profound than previously recognized, with implications for how we structure healthcare delivery and preventive health strategies.

Moving Toward Integrated Care

The study authors' emphasis on tooth loss as a "simple, non-invasive marker" of health risk suggests practical applications:

Potential Clinical Applications:

• Quick oral health screening in primary care settings
• Risk stratification for cardiovascular disease
• Identification of patients needing enhanced preventive care
• Population health monitoring through oral health indicators

The Economic Argument

While not explicitly addressed in this study, the findings have economic implications:

Cost Considerations:

• Hospitalization represents major healthcare expenditure
• Circulatory system diseases are particularly costly to treat
• Preventive dental care is relatively inexpensive
• Tooth preservation may reduce future hospitalization costs
• Improved oral health could reduce healthcare system burden

Cost-effectiveness analyses examining whether enhanced dental care reduces hospitalization rates would provide valuable evidence for healthcare policy decisions.

Conclusion: Your Mouth Reflects Your Health

This groundbreaking Canadian research adds compelling national evidence to the global understanding of oral-systemic health connections. The finding that missing five or more teeth nearly doubles the risk of circulatory disease hospitalization is both striking and actionable.

The study reinforces that oral health is not separate from general health—it's an integral component. The decline in edentulism rates over recent decades demonstrates that population-level improvements are possible through public health initiatives, improved access to care, and changing attitudes toward oral health.

The message for individuals is clear: Maintaining your natural teeth through preventive care and early intervention isn't just about preserving your smile—it may be protecting your overall health and reducing your risk of serious health complications requiring hospitalization.

For healthcare systems, the findings suggest that investments in oral health infrastructure and preventive dental care may yield returns in reduced hospitalization rates and improved population health outcomes.

As research continues to unveil the profound connections between oral and systemic health, the artificial separation between dental and medical care becomes increasingly difficult to justify. The mouth truly is the gateway to the body—and what happens there has consequences far beyond the oral cavity.

References:

Original Article:

"Missing teeth tied to significantly higher hospital risks, new Canadian study shows"

Published on: Oral Health Group