Interactions between stress, interleukin-1beta, interleukin-6 and cortisol in periodontally diseased patients

The aim of the present study was to measure interleukin-1beta, interleukin-6 and cortisol levels in the peripheral blood of periodontally diseased patients in order to record any interactions with psychosocial stress.

The test group comprised 16 patients with untreated and 14 with treated aggressive generalized periodontitis (AGP), five patients with untreated aggressive localized periodontitis (ALP) and five with chronic generalized periodontitis (CGP). The control group comprised 40 periodontally healthy probands. Blood was taken from the cephalic vein of all patients and controls at the same time (8 a.m.) each day. IL-1beta, IL-6 and cortisol levels were then measured with a sensitive ELISA, the 'Quantikine HS Immunoassay Kit' (Biermann Diagnostica, Bad Nauheim, FRG). The clinical examination covered probing depth, gingival recession, gingival index, plaque index and clinical attachment level. A questionnaire was used to ask the patients and controls about their attitude to life and the stress induced by their jobs and their families. Previous and current levels of tobacco consumption were also recorded. Statistical evaluation was based on the Mann-Whitney U-Wilcoxon test for comparison of blood serum values and clinical parameters between patients and controls, and the Kruskal-Wallis test for intergroup comparison. All data were correlated by means of Spearman's rank correlation coefficient, and significance levels relating to stress and smoking were determined with the chi-square test.

With respect to cortisol, the results showed no significant differences either between the patient groups or in comparison with the controls. IL-1beta was detected only in the AGP patients and their controls, but with no significant differences. IL-6 was detected in virtually all patients and controls, but with no significant differences. Only in the untreated AGP patients was IL-6 significantly elevated (P < 0.05) and a slight correlation with attachment loss recorded. In all AGP patients a slight correlation between IL-1beta and IL-6 was recorded. Evaluation of the questionnaire revealed a higher proportion of untreated AGP patients than of controls with a pessimistic attitude to life. In all AGP patients, family-induced stress and smoking were found to correlate with attachment loss. In the untreated AGP patients, smoking correlated with IL-1beta protein content, and in the controls there was a moderate correlation between smoking and IL-6 levels.

The present study found no correlation between the immunological mediators (IL-1beta, IL-6), glucocorticoids (cortisol) and the registered stress values. However, the patients with untreated AGP showed signs of a pessimistic attitude to life, and an elevated IL-6 level was recorded in the peripheral blood. As a restrictive factor it should be borne in mind that the number of patients investigated was too small for adequate conclusions to be drawn.