Is There a Link Between Dental Health and COPD?

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A small observational study found that people with severe chronic obstructive pulmonary disease (COPD) have poor dental hygiene practices and reduced oral health-related quality of life.

A small observational study found that people with severe chronic obstructive pulmonary disease (COPD) have poor dental hygiene practices and reduced oral health-related quality of life.

The researchers, writing in Chronic Obstructive Pulmonary Disease: Journal of the COPD Foundation, said that in the context of poor dental health, the greater number of teeth that a patient had correlated with worsened daily respiratory symptoms.

Previous reports have noted poor oral hygiene and dental problems in patients with COPD, but the researchers wrote that the impact of dental health on daily respiratory symptoms, such as cough and wheeze, was unknown.

Their hypothesis was that poor dental health is associated with worse symptoms, and that barriers to adequate dental care could possibly include impaired mobility due to illness or use of oxygen, continued smoking, or access to dental insurance.

The 60-day study included both healthy controls and those with COPD.

Participants were 40 years or older. To be included in the study, those in the COPD group had to have spirometric findings in the COPD group of mean forced expiratory volume in 1 second (FEV1) < 0.70 with an FEV1 < 50% predicted, and at least a 10 pack-year smoking history. The healthy controls had to have no airflow obstruction and no current smoking.


Due to slow enrollment, the FEV1 criteria for COPD participants was expanded to < 80% predicted.

A total of 30 participants were recruited for the study (10 healthy controls, 20 individuals with COPD). There were no differences in age, sex, or body mass index between the 2 groups. All 10 healthy participants completed the study, and in the COPD group, 1 died and 2 subjects withdrew after the first visit because they did not want to record daily symptoms. The analysis excluded the 2 who voluntarily withdrew.

During the first visit, participants completed questionnaires, had a dental exam, and a spirometry test. COPD participants were instructed to use an electronic daily diary to report respiratory symptoms. Participants scored their breathlessness (Borg scale), presence of sputum, cough, and wheeze, and perform 3 peak flow maneuvers. The highest peak flow measure was recorded and used.

At the second visit at the end of the study, another questionnaire was given, and the dental examination was repeated. All participants completed the Oral Health Impact Profile-14 (OHIP), a 14-question patient-centered and symptom-based survey of how oral health affects quality of life, on both visits.

Physical examination included counting the number of teeth and calculating the plaque index (PI) of each tooth, ranging from 0 to 5. Each surface of the tooth score was added together and divided by total surfaces measured to calculate the PI.

Both groups had similar teeth brushing habits, with almost every participant brushing at least once a day.

More of the healthy controls had a dental appointment closer to the time of enrollment than the COPD group, suggesting they had more frequent dental visits. Healthy controls also usually flossed once per day, compared with COPD participants, who rarely did. COPD participants had a history consisting of more dental infections, tooth extractions and higher prevalence of dentures, as well as fewer teeth and higher OHIP scores.

PI—the average amount of plaque on the surface of a tooth—was higher in the COPD group, but not to levels that reached statistical significance. Breathlessness was also positively correlated with the number of teeth, PI, and OHIP scores, but did not reach statistical significance.

The number of teeth had a significant positive correlation with percentage of days with cough, and wheeze, and moderate positive correlation with sputum production, which is different than past studies, the researchers noted.

After controlling for current smoking status, the number of teeth still had a significant positive correlation with percentage of days with cough (β=2.70, P = 0.04) and wheeze (β=2.65, P = 0.01); PI, however, did not significantly correlate with daily respiratory symptoms.

The researchers wrote that the microbiome of the lungs resembles the oral microbiome. More diseased teeth potentially provide a large reservoir of pathogenic bacteria, such as Haemophilus influenzae, in saliva, which, when microaspirated, could create worsened respiratory symptoms. In addition, chronic periodontitis is a common inflammatory disorder of the oral cavity and has previously been described in patients with COPD.

The researchers wrote that the study had several limitations: it was a small, single-center study and daily respiratory symptom data was collected over a relatively short period of time. And although periodontal disease has strong correlations with COPD, that was not measured in this study.


Gaeckle NT, Heyman B, Criner AJ, Criner GJ. Markers of dental health correlate with daily respiratory symptoms in COPD. Chronic Obstr Pulm Dis. 2018; 5(2):97-105. doi: