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ORIGINAL RESEARCH - BASIC AND CLINICAL
Year : 2014  |  Volume : 6  |  Issue : 2  |  Page : 92-97

Relationship between salivary levels of cortisol and dehydroepiandrosterone levels in saliva and chronic periodontitis


Department of Periodontics, Faculty of Dental Sciences, Sri Ramachandra University, Porur, Chennai, Tamil Nadu, India

Date of Web Publication28-Oct-2014

Correspondence Address:
R Suresh
Department of Periodontology and Implantology, Faculty of Dental Sciences, Sri Ramachandra University, Porur, Chennai, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2231-0754.143488

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   Abstract 

Aim: The aim was to investigate the association between cortisol and dehydroepiandrosterone (DHEA) levels in patients with periodontitis and healthy controls. Materials and Methods: Cortisol and DHEA levels in saliva were determined in 20 subjects, with clinical examinations including oral hygiene index, sulcus bleeding index (Muhlemann and Son) and probing depth was also performed. Statistical Analysis: Data were analyzed with the help of SPSS software package (version 7.0), and the significance level was set at 95% confidence interval. Mann-Whitney test and t-test were used to see the correlation between the groups. Results: In cortisol and DHEA the mean and standard deviation of periodontitis group were (2.6 ± 0.37) and (66.7 ± 8.7) respectively. Conclusion: This shows there is an increase in the mean value of cortisol and DHEA in periodontitis than the control group. Salivary cortisol and DHEA level were found to be increased in concordance with disease severity. This was statistically significant with P < 0.001.

Keywords: Cortisol, dehydroepiandosterone, periodontitis, probing depth, sulcus bleeding index


How to cite this article:
Mudrika S, Muthukumar S, Suresh R. Relationship between salivary levels of cortisol and dehydroepiandrosterone levels in saliva and chronic periodontitis . J Int Clin Dent Res Organ 2014;6:92-7

How to cite this URL:
Mudrika S, Muthukumar S, Suresh R. Relationship between salivary levels of cortisol and dehydroepiandrosterone levels in saliva and chronic periodontitis . J Int Clin Dent Res Organ [serial online] 2014 [cited 2019 Sep 17];6:92-7. Available from: http://www.jicdro.org/text.asp?2014/6/2/92/143488


   Introduction Top


Periodontitis is an inflammatory response of the periodontium, which involves the destruction of investing tissues around the teeth and results in loss of tooth support leading to tooth loss. Although, bacterial pathogens are required to initiate the disease process, it has become evident that their presence alone is not sufficient to cause the tissue destruction. [1],[2],[3] The etiological significance of biological and behavioral risk factors for periodontal diseases, such as smoking, advancing age, oral hygiene, and systemic diseases like diabetes mellitus has already been established. Other factors such as stress, depression and anxiety are not yet confirmed as absolute risk conditions but have been identified in some observational studies. [4],[5],[6]

Development of periodontal disease is related to the presence of periopathogenic bacteria and also conditions that alter the host resistance to these bacteria. Several studies have shown a positive correlation between psychological factors and periodontal disease [4],[7],[8] on the contrary few studies have shown no correlation. [9],[10],[11] Psychiatric patients seem to be more prone to periodontitis compared with patients without psychiatric disorders. [12],[13] A marker commonly used to study the function of the hypothalamus-pituitary-adrenal cortex axis during stress is the salivary concentration of cortisol. [14] Further, dehydroepiandrosterone (DHEA) is also known as an hypothalamic-pituitary adrenal (HPA)-related steroid hormone and has a positive correlation with depression severity. [15],[16] However, few reports regarding salivary DHEA have been presented in the dental field.

Hence, the detection of the biochemical marker can provide information about ongoing tissue destruction. The relationship between psychological factors and periodontitis necessitates carefully designed studies as it is known that psychological states can interfere with the course of chronic diseases. An understanding of this relationship may allow for an improvement in the prevention and treatment of periodontal diseases. Thus, the aim of this study was to evaluate salivary levels of cortisol and DHEA and analyze its association with periodontitis.


   Materials and methods Top


This cross-sectional study was conducted in the Department of Periodontology, Faculty of Dental Sciences, Sri Ramachandra University, Chennai, India. A total of 20 subjects of both genders with an age range of 35-60 years were included in the study. The study has been approved by Institutional Ethical Committee and Review Board. All individuals signed an informed consent before taking part in the study.

Study inclusion criteria were as follows: Individuals in the chosen age range with minimum 20 teeth excluding third molars; no antibiotics taken prior to 6 months of the initial examination and did not require antibiotic premedication for any systemic condition; no periodontal surgery performed in the areas to be treated within the last six months.

Subjects with systemic conditions associated with the periodontal disease or on medication related to periodontal alteration or psychotropic drugs; smoker or alcoholic; severe malocclusion or orthodontic treatment; pregnant and lactating females; were excluded from the study.

Clinical examinations

Periodontal evaluation


After all questionnaires were completed, periodontal clinical examination was carried out using a Williams probe (Hu-Friedy, Chicago, IL, USA). The clinical attachment level (CAL) and probing pocket depth (PPD) were measured at mesio-buccal; mesio-lingual; mid-buccal; disto-buccal; disto-lingual, and mid-lingual sides each tooth, excluding third molars. The plaque index [17] was used to record the presence of plaque at disto-facial, facial, mesio-facial, and lingual surfaces. Only plaque of the cervical third of the tooth was evaluated. The gingival condition was assessed using the gingival index [18] at four surfaces: Disto-facial papilla, facial margin, mesio-facial papilla and entire lingual gingival margin. All clinical data were collected by a single examiner, who was calibrated prior to the commencement of the study. A case of chronic periodontitis was defined as subjects with CAL ≥3 mm and PPD of ≥4 mm in at least 30% of the teeth examined. [19]

Saliva collection

Stimulated whole saliva was collected from the subjects between 9:00 a.m. and 11:00 a.m. and cortisol and DHEA levels were determined using salivary ELISA kit. Saliva samples were collected from all patients after gingival crevicular fluid (GCF) collection. To avoid contamination of the oral cavity as a result of food intake, the patients were instructed not to eat or drink 1 h prior to sampling. Patients were asked to rinse their mouth with distilled water. One ml of unstimulated saliva was collected using drooling method in a 5 ml sterile plastic test tube. All samples were immediately centrifuged for 3000 rpm for 10 min at room temperature. The supernatants were then frozen at −70°C, pending analysis.

Cortisol and dehydroepiandrosterone level analysis

The concentration of cortisol in saliva (ng/mL) was measured using a salivary cortisol enzyme immunoassay kit (Salimetrics, State College, PA), with a lower sensitivity limit of 0.07 ng/mL, while that of DHEA (pg/mL) was determined using a salivary DHEA enzyme immunoassay kit (Salimetrics, State College, PA), with a lower sensitivity limit of 10 pg/mL.

Statistical analysis

Data were analyzed using SPSS software package (version 7.0), and the significance level was set at 95% confidence interval. Mann-Whitney test and t-test were used to see the correlation between the groups.


   Results Top


Since P < 0.01, there is significant difference between control and cases at 1% level with regard to oral hygiene index (OHI), bleeding index, probing depth (PD), Coritsol and DHEA. Based on the mean score, OHI, bleeding index, PD, coritsol and DHEA have more in cases than control [Figure 1] and [Table 1], [Table 2].
Table 1: Mann-Whitney test for significant difference between cases and control for ohi, bleeding index, probing depth and dhea

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Table 2: Correlation coefficient between bleeding index and probing depth

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Figure 1: Bar diagram shows comparison between correlation coeffi cient between control and cases for oral hygiene index, bleeding index, probing depth, coritsol and dehydroepiandrosterone

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The correlation coefficient between bleeding index and PD is 0.908 which indicate 90.8 percentage positive relationships between bleeding index and PD and is significant at 1% level. Hence, the increase in bleeding index leads to increase in PD. Similarly, the other variables' correlations are also positive and significant at 1% level and are shown in the following graph [Figure 2], [Figure 3], [Figure 4], [Figure 5].
Figure 2: Scatter diagram shows correlation coefficient between probing depth and cortisol

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Figure 3: Scatter diagram shows correlation coeffi cient between probing depth and dehydroepiandrosterone

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Figure 4: Scatter diagram shows correlation coefficient between bleeding index and dehydroepiandrosterone

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Figure 5: Scatter diagram shows correlation coefficient between bleeding index and cortisol

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   Discussion Top


Despite the general understanding of predisposing factors for chronic periodontitis, the complete variability on periodontal disease severity remains unclear. [20] This variability can be explained, at least in part, by psychosocial factors. [4] Several studies suggest a relationship between these factors and clinical characteristics of periodontal disease. [4],[21] However, the criteria used to classify periodontal disease are, usually, not the same. The various methodologies applied in these studies as well as the absence of a control group and a lack of control for confounding variables for periodontal disease makes it difficult to conclude on the actual effects of psychosocial factors over periodontal pathogenesis. [22] This cross-sectional study included 20 patients divided into two groups; we investigated cortisol and DHEA levels and periodontal status in subjects with periodontitis and clinically healthy subjects, and found that levels of the salivary stress-related hormones cortisol and DHEA were useful for screening in subjects who had periodontitis.

The association between periodontitis and stress-related hormones has been largely overlooked, with only few known human studies of the associations between cortisol and DHEA in saliva and periodontitis reported. Hilgert et al. [23] found a positive association between salivary cortisol and periodontitis, while hypercortisolemia was independently associated with the severity of periodontitis, as defined by CAL (mean CAL in mm), and the extent of periodontitis, as defined by PD (26% vs. 26% of sites with PD mm) or CAL (30% of sites with CAL mm vs. %).

Measurement of biomarkers in saliva has many advantages, as the procedure is stress-free and noninvasive, and allows for frequent and rapid sampling, whereas diurnal rhythm, artificial changes due to food or drinking substances, and blood-contamination are some of the disadvantages. Thus, the sampling was carefully performed. In order to minimize any circadian rhythm effects, we selected the period between 11:00 a.m. and 1:00 p.m. for obtaining saliva samples, which has been reported to be stable in regard to daytime hormonal levels in nonsmokers. [24]

A periodontal probe is generally used for periodontitis screening during community-based oral health check-ups, though several problems, including cost, burden on the subject, prevention of infection, and manpower needs, have been pointed out. On the other hand, progress is being made in the development of various screening tests for periodontitis using enzymes, [25] cytokines, [26] and antimicrobial proteins [27] in saliva. We think that it would be better to combine several tests that reflect the multiple risk factors associated with periodontitis and not depend on results of a single test. On the other hand, it is important to consider the cost-effectiveness when promoting such screening tests for clinical use. In the near future, it is anticipated that screening tests used for a large population will be noninvasive and less burdensome for the subjects, with no requirements of specific devices or instruments, or for individual examinations by an expert as well as reasonable cost-effective performance.

A limitation of the present study is that our subjects were generally in good health and noninstitutionalized. In addition, the percentage of subjects with severely extensive periodontitis among all subjects analyzed was low. Thus, these findings may indicate that the association exists primarily in systemically and orally healthy elderly individuals. Further, the usefulness of cortisol and DHEA as predictors for periodontitis cannot be determined from our findings, and a longitudinal study is necessary to determine the relationships of those hormones to the progression of periodontitis.

All the clinical measures such as OHI, GBI, PPD, and CAL were statistically different among the two groups. Since P < 0.01, there is significant difference between control and cases at 1% level with regard to OHI, Bleeding index, PD, coritsol and DHEA. Based on the mean score, OHI, bleeding index, PD, coritsol and DHEA levels have more in cases than control. These results are in agreement with previous studies by Klages et al. [28] and Johannsen et al. [3] The increased level of gingival inflammation in these subjects can be explained by both an indirect and direct influence, in which the indirect influence would involve behavioral changes. The direct influence might involve modulation of the HPA axis, leading to endocrine imbalance and consequently lowered host resistance as suggested by Genco. [29] Analysis of the free cortisol (active form of cortisol) in serum is usually time consuming and expensive and not suitable for clinical routine. Salivary cortisol levels were demonstrated to have an excellent correlation with free serum cortisol levels. [30],[31] In the present study, unstimulated saliva was collected from all the participants. Most methods of saliva collection are easy to perform, noninvasive, rapid, and generally require no special equipment or expertise. Salivary analysis may offer a means of assessing subject-level (as opposed to site-level) risk or status. In the current study, cortisol and DHEA levels ranged from undetectable levels to detectable limit. Salivary cortisol and DHEA levels in Group 2 were higher than Group 1. It has been suggested that elevated levels of Cortisol and DHEA can suppress several host response mechanisms. [22] This could lead to an impaired immune system function, which might increase the risk for periodontitis.

The results of the present study indicated a statistically significant association between the levels of salivary cortisol and DHEA with OHI, GBI, PPD and CAL of Group 2, which was supported by previous studies. [22],[23],[32] In our study, CAL showed high statistical significance in Group 2. Since CAL can be regarded as a result of an inflammatory burden from the past into the present, in contrast to PPD level which reflects the current pathophysiological status of periodontitis, the findings from our study may be attributed to dysregulation of the stress system, in which the HPA axis is chronically activated due to anxiety in patients with chronic periodontitis. [33] The presence of anxiety as a symptom of dysregulation of HPA axis may have an add-on effect on the progression and severity of the periodontal disease.

A relationship between stress-related hormones and periodontitis could be explained, at least in part, by the inhibitory effects of activation of the HPA axis on the inflammatory immune response, because all components of immune response are inhibited by cortisol. [34],[35] During the activation of the HPA axis, the T-helper phenotype of an individual is influenced by inhibition of interleukin-12 (IL-12) and stimulation of IL-10 secretion by macrophages. These changes have major suppressive effects on immune and inflammatory responses and increasing susceptibility, which in turn makes local periodontal tissues vulnerable to pathogenic microorganisms. [36]

Analysis of cortisol and DHEA levels in saliva has certain merits over GCF as a larger volume of the sample can be collected using simple methods with less chair side time, also ease of storage of sample. Hence, it can be easily incorporated in clinical practice. A single sample of saliva was the limitation of the study. Furthermore, there was unequal gender distribution, the effect of gender on salivary gland secretion and in turn on cortisol and DHEA level could not be assessed. Besides this, the present study comprised a control group and confounding factors like smoking, poor oral hygiene, and systemic disease like diabetes were taken into consideration. Subjects with other psychiatric illness and those anxious with history of past anxiety episode, who were on medication were excluded. Cortisol and DHEA level estimation was evaluated in saliva and which is noninvasive and less expensive compared to assessment in the serum. In the present study ELISA technique was used, which is economic, sensitive, and reliable compared to other techniques.

In summary, we found a significant association between the salivary steroid hormones cortisol and DHEA levels and severity of periodontitis. These results indicate that these stress-related hormones are useful indicators of the risk for periodontitis as they showed moderate levels of sensitivity and specificity for periodontitis. Within the study limitations, the present method of determining cortisol and DHEA levels may be included as a possible screening test for periodontal disease in the near future. Additional approaches to reveal a new type of screening test system for periodontitis as an alternative to the conventional probing method are required.


   Conclusion Top


Salivary cortisol and DHEA levels are valuable biomarkers for evaluating a part of the etiopathogenesis of chronic periodontitis. Additional controlled, longitudinal studies may elaborate the significance of salivary and GCF cortisol as a potential marker for periodontal disease.

 
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
 
 
    Tables

  [Table 1], [Table 2]


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