Avaliação de parâmetros salivares, sorológicos e alimentares em indivíduos com e sem diabetes Mellitus tipo 1

Abstract

The present thesis has objectives divided into two chapters. Chapter 1 aims, through a systematic review with meta-analysis, to investigate whether diabetes mellitus type 1 (DM1) promotes changes in salivary levels of immunoglobulins (Ig) A, G and M when compared to that in individuals without DM1. The search strategy was performed in eight databases and gray literature, with nine studies being selected. Diabetic patients had a significant reduction in salivary flow (p=0.0008; Cohen's d = -0.19, 95% CI= -0.33, -0.05), but not significant enough to modify the IgA concentration (p=0.120; Cohen's d) = 0.58, 95% CI = -0.15, 1.32). However, DM1 increased IgA concentration by reducing salivary flow (Cohen's d = 0.84; 95% CI = 0.36, 1.32), with a strong estimate of effect (p=0.0006). Regarding IgG, no significant change was observed with DM1 in the patients' saliva (p=0.420). There was no significant variation in salivary IgM levels (p=0.300). Chapter 2 aimed to evaluate the association between salivary parameters: glucose (GS), flow, pH and proteins concentration; fasting and postprandial blood glucose; glycated hemoglobin; caries (CI), plaque (PI) and gingival bleeding (BI) indexes; and diet in children with (CDM1) and without (SDM1) DM1. The CDM1 and SDM1 groups were composed of 36 and 49 patients, respectively, matched for sex and age. For the evaluation of CI, PI and BI, a clinical examination was performed. The dietary pattern was obtained through the diet diary for the 24 hours prior to the appointment. Unstimulated total saliva was collected. Salivary protein concentration was analyzed by the bicinchoninic acid method. The Kolmogorov-Smirnov, Mann-Whitney and Spearman tests were used, considering p<0.05 and Statistical Packcage for the Social Sciences (SPSS®) software. SG, CI, PI and BI were submitted to the multiple linear regression model. There was no difference in mean salivary flow (p=0.649), CI (p=0.868), IP (p=0.618) and protein concentration (p=0.712). CDM1 had lower BI (p=0.031) and pH (p<0.001), higher values for mean number of meals (p<0.001) and carbohydrate-based meals (p<0.001), lower mean of intervals (p<0.001) and higher SG (p=0.036). Salivary glucose was directly correlated with fasting glucose (p=0.043) in CDM1 and showed positive collinearity with fiber count (p=0.018) and fasting glucose (p=0.048). In the CDM1 group, female gender (p=0.033) was significantly associated with plaque index, while the number of meals with sucrose showed inverse collinearity with this parameter (p=0.046) and pH (p=0.034) showed direct collinearity. The bleeding index showed direct collinearity with age (p=0.043) and with postprandial blood glucose (p=0.023). It was concluded, then, that salivary glucose was not associated with the other variables in SDM1, but with fasting glucose and diet in CDM1. Future studies are needed to confirm the use of salivary glucose in the early diagnosis and monitoring of DM1. The findings of the present research suggest that more studies with similar saliva sampling methods would be carried out.