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Table of Contents   
ORIGINAL RESEARCH  
Year : 2021  |  Volume : 32  |  Issue : 1  |  Page : 44-50
Obstructive sleep apnea and periodontitis: A cross-sectional study


Department of Periodontics, Vokkaligara Sangha Dental College & Hospital, Bangalore, Karnataka, India

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Date of Submission09-Jul-2019
Date of Decision15-Nov-2019
Date of Acceptance02-Jul-2020
Date of Web Publication13-Jul-2021
 

   Abstract 


Objectives: (1) To assess the risk of Obstructive Sleep Apnea (OSA) using a pre-designed questionnaire; (2) To assess the periodontal parameters like pocket probing depth (PPD) and clinical attachment loss (CAL) in the study subjects and (3) To determine the association between the shared risk factors of OSA and periodontitis. Background of the Study: Periodontitis is a microbially associated, host-mediated inflammatory disease that results in the loss of periodontal attachment. It has multifactorial etiology and has been linked to an array of systemic diseases. Though both periodontitis and obstructive sleep apnoea (OSA) share some common risk factors, the insight into the hypothetical speculative link remains vague. This study intended to probe into the association between periodontitis and OSA. Methodology: A cross-sectional study was conducted on 250 subjects. The subjects were explained the nature of the study and written informed consent was obtained for participation in the study. The patients were administered a STOP-BANG questionnaire following which the periodontal parameters were recorded. The data obtained was analyzed by descriptive and inferential statistics. Results: A statistically significant increase in PPD and CAL scores were seen with the increase in OSA scores. A significant moderate positive correlation was found between OSA scores and PPD [r = 0.58, P < 0.001] and CAL [r = 0.55, P = 0.001]. Males were at increased risk for OSA and periodontitis. Age, hypertension and BMI which are the risk factors for periodontitis were also significantly higher in subjects at high risk for OSA. Conclusion: This study found a moderate positive association between periodontitis and OSA.

Keywords: Hypertension, male, obesity, OSA, periodontitis, sleep apnoea

How to cite this article:
Mukherjee S, Galgali SR. Obstructive sleep apnea and periodontitis: A cross-sectional study. Indian J Dent Res 2021;32:44-50

How to cite this URL:
Mukherjee S, Galgali SR. Obstructive sleep apnea and periodontitis: A cross-sectional study. Indian J Dent Res [serial online] 2021 [cited 2021 Oct 17];32:44-50. Available from: https://www.ijdr.in/text.asp?2021/32/1/44/321373



   Introduction Top


Obstructive sleep apnoea (OSA) is a disorder in which a person frequently stops breathing during sleep. It results from an obstruction of the upper airway that occurs because of the inadequate motor tone of the tongue and/or airway dilator muscles.[1] OSA affects 2–4% of the adult population with prevalence in India varying from 6.2% to 13.7% with around 33.5% of the obese people being at high risk for OSA.[2] It has been hypothesised that intermittent hypoxia occurring in OSA may contribute to systemic inflammatory response through the activation of transcription factors and increased production of cytokines.[3]

Periodontitis is a microbially associated, host-mediated inflammatory disease that results in the loss of periodontal attachment.[4] It has multifactorial aetiology and has been linked to an array of systemic diseases. The periodontal tissues mount an immune-inflammatory response to bacteria and their products at the site of periodontal infection and systemic challenge with these agents' results in an acute phase response contributing to systemic inflammatory burden.

As both OSA and periodontitis are conditions associated with systemic inflammation and share many common risk factors, they are likely to be associated. Several studies have been conducted to determine the nature and the extent of the relationship between the two conditions in different populations.

Although estimates of the prevalence of OSA in the Indian population are available, not much information is available on the association between the two conditions in our population. This hospital-based study intended to explore the relationship between OSA and periodontitis using a validated screening questionnaire.


   Methodology Top


Study population

250 subjects were recruited from patients reporting to the Outpatient Department (OPD) of Periodontics, VS Dental College and Hospital, Bangalore and Dental OPD of KIMS Bangalore based on the selection criteria.

Ethical clearance

The study was conducted per revised Declaration of Helsinki, 2013 and the authors followed the ICMJE guidelines while conducting the research. Ethical clearance was obtained from the institution before conducting the study (KIMS/IEC/A55-2019).

Inclusion criteria

  • Be ≥18 years of age
  • Have ≥24 teeth at the time of examination


Exclusion criteria

  • Teeth with full crowns or restorations without CEJ reference.
  • Patients who received any periodontal treatment, including oral prophylaxis in the past 1 year.
  • Patients who require antibiotic prophylaxis
  • Patients who have any infectious diseases like HIV Infection, TB.


All the participants were informed of the nature of the study. It was made clear to all subjects that participation was voluntary. Only those who gave written informed consent were included in the study. Following consent, data were collected on demographic characteristics which included age, gender, socioeconomic status, cigarette smoking and alcohol consumption. Height and weight were measured to calculate the body mass index. Neck circumference and blood pressure were measured. Periodontal parameters assessed were PPD and CAL using a calibrated periodontal probe. PPD was measured as the distance from the gingival margin to the base of the pocket and CAL was measured as the distance from CEJ to the base of the pocket. Full mouth examination was carried out at six sites around each tooth and the scores were averaged. All measurements were made by a single examiner who was calibrated by intra-examiner reliability testing methods (ICC = 0.81 and 0.78 for PPD and CAL, respectively).

The risk for OSA was assessed by the use of the STOP-BANG questionnaire. This questionnaire contains eight dichotomous questions, which include four self-reported questions (snore, day sleep, observed stop breathing and BP) and four questions to be assessed by the examiner (BMI, age, neck circumference and gender).

Based on the total score, the subjects were classified into low (0–2), medium (3–4) and high risk (5–8) categories. The subjects were categorized into obese and non-obese based on the Asian criteria for BMI. The Asian criteria for BMI according to the Asian-Pacific cutoff points [underweight (<18.5 kg/m2), normal weight (18.5–22.9 kg/m2), overweight (23–24.9 kg/m2) and obese (>25 kg/m2)] varies from the conventional WHO classification [underweight (<18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (25–29.9 kg/m2) and obese (>30 kg/m2)].[5],[6]

The study further categorised subjects into healthy, mild, moderate and severe periodontitis.[4],[7]

Statistical analysis

Statistical Package for Social Sciences [SPSS] for Windows Version 22.0 released 2013. Armonk, NY: IBM Corp., was used to perform statistical analyses.

Descriptive statistics

Descriptive analysis of all the explanatory and outcome parameters was done using median and IQR [Inter-Quartile Range] for quantitative variables, frequency and proportions for categorical variables. The study data was subjected to the Shapiro–Wilk normality test. As the data was not following the normal distribution, the analysis was done by the non-parametric test.

Inferential statistics

The Pearson correlation test was used to estimate the relationship b/w OSA scores, age and periodontal parameters. Chi-Square/Mann–Whitney U test was used to perform a gender-wise comparison of different variables among the study participants. The Kruskal–Wallis Test followed by Mann–Whitney Post hoc analysis was used to compare the neck diameter and periodontal parameters with different OSA grades. The level of significance was set at P < 0.05.


   Results Top


Among the 250 participants, nine subjects (3.6%) were <20 years of age, 108 (43.2%) were in the age group of 21– 40 years, 98 (39.2%) in the age group of 41–60 years, 35 (14%) were in the age group of 61–80. Of the total, 150 (60%) participants were men while 100 (40%) were women [Table 1] and [Figure 1]. Based on the clinical case definition of periodontitis, 109 (43.6%) of the study subjects had periodontitis while 141 (56.4%) of subjects were periodontally healthy. Of the periodontitis patients, 71 (28.4) had mild periodontitis while 24 (9.6%) had moderate and 14 (5.6%) had severe periodontitis [Table 5] and [Figure 5]. Among all participants, 55 (22%) were in the high-risk OSA category, 75 (30%) in the moderate risk category and 120 (48%) in the low-risk OSA category [Table 1] and [Figure 2], [Figure 4]. 51 (20.4%) participants reported hypertension, 91 (36.4%) reported daytime sleep and 88 (35.2%) participants were overweight while 56 (22.4%) were obese [Table 1], [Table 2], [Table 3] and [Figure 1], [Figure 3], [Figure 4], [Figure 5].
Table 1: a. Distribution of study variables among study participants

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Table 2: Genderwise comparison of study variables using Chi Square/Mann Whitney U Test

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Table 3: Relationship with study participant characteristics and high risk for Obstructive Sleep Apnea using Chi Square test

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Table 4: Comparison of neck diameter and peridontal parameters with different OSA Grades using Kruskal Wallis test followed by Mann Whitney post hoc analysis

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Table 5: Comparison of periodontal status between different OSA grades using Chi Square Test

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Figure 1: Distribution of study variables. (a) Age wise distribution among study participants. (b) Gender wise distribution among study participants. (c) Distribution of study participants based on OSA grades. (d) Distribution of study participants characteristics

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Figure 2: (a) Distribution of study participants based on BMI levels. (b) Scatterplot depicting the relationship between Age [in years] & OSA scores. (c) Scatterplot depicting the relationship between OSA scores & periodontal parameters. (d) Gender wise comparison of study variables [Hypertension & Day Sleep]

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Figure 3: Box and Whiskers plot comparing the study variables and patient characteristics. (a) Gender based difference in neck diameter of study participants. (b) Gender based difference in relation to OSA scores and periodontal parameters. (c) Comparison of neck diameters based on OSA scores. (d) Difference in periodontal parameters based on different OSA grades

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Figure 4: Relationship between study participants, characteristics and different grades of OSA

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Figure 5: Comparison of periodontal status between different groups of OSA

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In our study, 78.3% of the low-risk category people were periodontally healthy compared to 50.7% in the moderate risk category and 16.4% in the high-risk category. 19.2% of the low-risk category participants were having mild periodontitis compared to 32.0% in the moderate risk and 43.6% in the high-risk group. 2.5% of the low-risk category participants were having moderate periodontitis compared to the 12.0% in moderate risk and the 21.8% in the high-risk group [Table 5]; [Figure 5].

Interestingly, none of the study participants at low risk were found to have severe periodontitis. 5.3% of the moderate risk category were found to have severe periodontitis compared to 18.2% of the high-risk category participants and these differences were statistically significant (p < 0.001). Multiple comparison of periodontal status based on severity of OSA also showed a statistically significant association between the increasing severity of periodontitis with increased risk for OSA [Table 6]; [Figure 5] (p < 0.001).
Table 6: Multiple comparison of periodontal status of study subjects based on OSA grades

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Gender-wise comparison of BP and day sleep showed no significant difference between males and females while the neck diameter, OSA scores, CAL scores and PPD scores were significantly higher in males compared to females (p < 0.05) [Table 2], [Table 4]; [Figure 3], [Figure 4], [Figure 5]. Also, there was a significant relationship between age, gender, BP, Day sleep and BMI and high risk for sleep apnoea [Table 3], [Figure 4] (p < 0.001) and a significant positive moderate correlation was observed between OSA and age, PPD and CAL [Table 1], [Table 4], [Table 5]. There were statistically significant differences in neck diameter, PPD and CAL in subjects with varying risk for OSA [Table 4], [Table 5] [Figure 2], [Figure 3], [Figure 5] (p < 0.001).


   Discussion Top


The association between periodontal disease and obstructive sleep apnoea (OSA) has been questioned and explored in several studies with varied results indicating that there is not enough evidence to support the association. Also, most of the studies finding an association have been carried out in Caucasians and Hispanics with very few in the Dravidian population.[8] This is the first study to examine and report a significant association between periodontitis and OSA in the South Indian population.

In our study, periodontitis was defined and stratified based on the world workshop on classification of periodontal and peri-implant disease.[4],[7] The severity of periodontitis increased with increased grades of OSA indicating an association between the two conditions. Our findings are similar to those reported by Sanders et al. among the Hispanic community of the Latino population.[9] Other studies in different populations[8],[9],[10],[11] have also reported a significant association between periodontitis and OSA. A study by Al Habashneh et al.[12] including 294 men in Jordan evaluated the association between periodontitis and OSA using the Berlin questionnaire. Subjects at high risk of OSA were more frequently and severely affected by periodontitis than those at low risk of OSA. In contrast, studies by Loke et al.[13] and Sales- Peres et al.[14] reported no significant association between periodontitis and OSA.

The biologic mechanisms linking periodontitis and OSA and the direction of relationship are still controversial. The pathophysiology of OSA and periodontitis involves oxidative stress and chronic inflammation. Periodontitis causes an inflammatory burden through the local production of inflammatory mediators and cytokines entering the systemic circulation. Severe periodontitis means a greater inflammatory burden.[15] Intermittent hypoxia associated with OSA may also contribute to systemic inflammation and oxidative stress.

Although earlier studies have failed to demonstrate the contribution of OSA to systemic inflammatory burden[16],[17], a recent systematic review and meta-analysis published by Al-Jewair in 2015 investigating the comorbid relationship between the two conditions reported a significant association of IL-6 with both conditions concluding that an association is still possible.[18]

The simultaneous presence of periodontitis and OSA in an individual could be attributable to the common risk factor such as tobacco use, sex (male), ageing, alcohol consumption, obesity and diabetes. Our results showed a significant increase in OSA severity with increasing age, obesity, neck diameter and male gender. Larger neck diameter and periodontitis were found to be more prevalent among males whereas there were no significant differences in the prevalence of day sleep and hypertension between males and females. More than 50% of our study subjects were above 40 years of age of which 75% of them were in the high-risk category for OSA. 57.6% of the subjects were overweight and obese of which about 27% were in a high-risk category for OSA. 20.4% of the study subjects were hypertensive of which 52.9% were in a high-risk category for OSA. 60% of the subjects were males of which 30.7% were in a high-risk category. A significant relationship was observed between OSA, neck diameter, age and severity of periodontitis. The association could be attributed to the shared risk factors between the two conditions; Age and male gender are non-modifiable risk factors for periodontitis and OSA. Obesity is a modifiable risk factor for periodontitis and OSA. The association between OSA and hypertension has been previously reported.[19] More than 50% of people with OSA have hypertension and OSA is one of the most common causes of secondary and refractory hypertension. Also, the incidence of hypertension is observed to be more in obese OSA patients than non-obese patients. This finding has been supported by several cross-sectional, longitudinal and treatment studies.[17],[20],[21] OSA contributes to or exacerbates obesity-related hypertension.[19],[20]

Mouth breathing is another mechanism by which the two conditions could be related. In the study by Seo et al.[10], the prevalence of mouth breathing appeared to be higher in patients with OSA. Dry mouth, a consequence of mouth breathing may be associated with increased plaque accumulation due to diminished self-cleansing mechanisms contributing to more periodontal destruction. However, our study did not assess mouth breathing in the subjects enrolled in the study.

A wide variation in the definition of periodontitis exists in the literature which can contribute to variation in the results.[8],[9],[11],[22] We employed the current diagnostic criteria for defining periodontitis.[4] Also, a full-mouth periodontal examination was carried out, unlike other studies that conducted a partial mouth examination.[8] Also, most studies have used either the Berlin questionnaire[2],[12] or Epworth Sleepiness Scale[14] with/without polysomnography[8],[10] tests to diagnose the risk of OSA. We used the STOP-BANG diagnostic questionnaire due to its high-quality methodology and reasonably accurate results in screening for OSA in the sleep clinic and surgical population.[22],[23],[24]

The diagnostic value of any questionnaire is debatable because of its subjective nature. Therefore, the questionnaire was validated in a small sample of 25 subjects in the high-risk category by polysomnography to confirm the diagnosis and severity of OSA. The PSG was recorded by an experienced sleep technologist (using Alice 5 Diagnostic Sleep System machine; Germany), and the patients were graded into normal, mild, moderate and severe categories based on the AHI index.[25] Among the 25 subjects, 64% (16 subjects) had severe sleep apnoea, 32% (8 subjects) had moderate sleep apnoea and only 4% (1 subject) have mild sleep apnoea. On average, 91% of the time all the 25 patients had the O2 saturation below 90% with the lowest O2 saturation of 27% recorded for one subject.

This was a hospital-based cross-sectional study limited by a small sample size. A comparative study with a control group, adjusting for confounders, and assessing the impact of treatment of one condition on the other may help in determining the true nature of the relationship between the two conditions.


   Conclusions Top


This study found a moderate positive association between periodontitis and OSA. The severity of periodontitis increased with higher grades of OSA. A significant increase in OSA severity was observed with increasing age, obesity, neck diameter and male gender. OSA could be a risk factor for periodontitis and an early diagnosis, intervention and treatment of OSA may improve the prognosis of periodontitis and vice-versa.

Clinical relevance

OSA and periodontitis have an impact QOL of individuals. OSA may increase the risk of periodontitis. Tooth loss resulting from periodontitis may limit the treatment choices of OSA. STOP-BANG questionnaire is a rapid and effective method to identify patients at risk for sleep apnoea in a dental office so that patients could be referred further for more objective evaluation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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Correspondence Address:
Dr. Suman Mukherjee
(Periodontics & Oral Implantology), Shakuntala Gardens, Block D, Ranchi Road, Purulia - 723 101, West Bengal
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijdr.IJDR_534_19

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