Correlation of Salivary Glucose Levels with Blood Glucose Levels in Patients with Diabetes Mellitus: A Cross-sectional Study from KLE’s Dr. Prabhakar Kore Hospital and Medical Research Centre, Belagavi, Karnataka

Background: Saliva has been studied as a better indicator of disorders and diseases than blood. Specifically, the salivary glucose level is considered to be an indicator of diabetes mellitus (DM). However, saliva collection methods can affect the salivary glucose level, thereby affecting the correlation between salivary glucose and blood glucose. Therefore, this study aims to identify an ideal saliva collection method and to use this method to determine the population and individual correlations between salivary glucose and blood glucose levels in DM patients and healthy controls. Finally, an analysis of the stability of the individual correlations is conducted. Methods: This study included 40 age-matched DM patients and 40 healthy controls. In the fasting state, saliva was collected using six saliva collection methods, venous blood was collected simultaneously from each study participant, and both samples were analyzed at the same time using glucose oxidase peroxidase. A total of 20 DM patients and 20 healthy controls were arbitrarily selected from the above participants for one week of daily testing. The correlations between salivary glucose and blood glucose before and after breakfast were analyzed. Finally, 10 DM patients and 10 healthy controls were arbitrarily selected for one month of daily testing to analyze the stability of individual correlations. Results: Salivary glucose levels were higher in DM patients than healthy controls for the six saliva collection methods. Compared with unstimulated saliva, stimulated saliva had decreased glucose level and increased salivary flow. In addition, unstimulated parotid salivary glucose was most correlated with blood glucose level (R2 = 0.9153), and the ROC curve area was 0.9316, which could accurately distinguish DM patients. Finally, it was found that the correlations between salivary glucose and blood glucose in different DM patients were quite different. The average correlation before breakfast was 0.83, and the average correlation after breakfast was 0.77. The coefficient of variation of the correlation coefficient before breakfast within 1 month was less than 5%. Conclusion: Unstimulated parotid salivary glucose level is the highest and is most correlated with blood glucose level, which can be accurately used to distinguish DM patients. Meanwhile, the correlation between salivary glucose and blood glucose was found to be relatively high and stable before breakfast. In general, the unstimulated parotid salivary glucose before breakfast presents an ideal saliva collecting method with which to replace blood-glucose use to detect DM, which provides a reference for the prediction of DM.

Salivary glucose levels and oral candidal carriage in type II diabetics

Aim: The study was undertaken: 1) To assess salivary glucose (SaG) levels in diabetic and nondiabetic subjects and to determine if saliva could be used as a noninvasive tool to diagnose and monitor Type II diabetes mellitus. 2) Correlation of SaG levels with serum glucose (SeG) levels in nondiabetic and diabetic patients. 3) To correlate the oral manifestations of diabetes mellitus with serum and SaG levels. Material and Methods: Both fasting and postprandial serum and SaG levels were analyzed from 70 Type II diabetic and 70 nondiabetic subjects. The detailed examination of oral cavity in relation to periodontal and dental status and subjective oral complaints were recorded. The obtained values were subjected to statistical analysis. Results: The mean fasting salivary glucose (FSaG) was 5.469 + 2.347 mg/dL and 7.634 + 4.468 mg/dL in nondiabetic and diabetics, respectively (P = 0.000) and postprandial salivary glucose (PSaG) was 6.434 + 2.111 mg/dL and 8.736 + 4.962 mg/dL in nondiabetic and diabetics, respectively (P = 0.000). The positive correlation was found between SeG levels and SaG in diabetics (P = 0.000). Strong positive correlation was observed between SeG and SaG with oral manifestations in Type II diabetic patients (P < 0.05). Conclusion: Saliva can be a useful tool in regular monitoring of “already diagnosed Type II diabetics” (by their SeG levels) rather than diagnosing subjects with “unknown status of diabetes mellitus.” Strong positive correlation exists between SeG level and SaG level with oral manifestations in Type II diabetic patients.

The prevalence of diabetes mellitus is increasing steadily in India. Understanding blood glucose level is the key to both diagnosis and management of diabetes mellitus. However, there is an on-going need for improvements in noninvasive, point-of-care tools for the diagnosis and prognosis of diabetes. Assessing a relationship between the blood glucose level and its concentration in other body fluids such as the saliva can help in developing a conservative method for blood sugar assessment replacing venous blood sampling. Diabetes mellitus is known to cause changes in salivary composition. Hence, this study was undertaken to evaluate the relationship of blood glucose level with salivary glucose in diabetic and nondiabetic patients. The study sample included 100 diabetic patients and 100 nondiabetic patients aged above 35 years of age. Fasting blood and salivary glucose levels were measured in the two groups. Pearson's correlation coefficient was used to assess the correlation of blood glucose with salivary glucose in the two groups. The results of the study revealed an increase in the level of fasting salivary glucose in diabetics compared to that of nondiabetic patients. It also showed a highly significant positive correlation between fasting salivary glucose and serum glucose in both diabetic patients and in controls. From this study, it can be concluded that fasting salivary glucose level can be used as a noninvasive diagnostic, as well as a monitoring tool to assess the glycemic status of Type II diabetes mellitus patients.

Diabetes mellitus (DM) is a clinical syndrome characterized by hyperglycemia because of the absolute or relative deficiency of insulin. It requires frequent monitoring of glucose levels in the body which requires multiple pricking at regular intervals. It could be physically and psychologically traumatic to the patient. This necessitates an alternative to measure the glucose level. This study aims to correlate the salivary glucose level with the blood glucose level in diabetes patients. The cross-sectional study was conducted in 60 patients. Patients were categorized into two groups as Group A- 30 patients with diabetes and Group B- 30 healthy subjects. The blood and saliva samples were collected from the patients and the glucose levels were recorded. All these data were entered in Microsoft Excel and analyzed statistically using SPSS software. The mean (±SD) value of the random blood and salivary glucose level in diabetic patients were found to be 251.4±82.66 and 2.85±0.85 respectively and the mean blood and salivary glucose level in healthy subjects were found to be 101.12±10.14 and 0.875±0.13 respectively. There was a significant correlation between the salivary glucose levels and blood glucose levels among diabetes (p-0.00) and healthy individuals (p-0.00). From the data, the diagnostic accuracy was found to be 100%. Thus, Saliva could be used as an alternative to blood for monitoring the glucose status in diabetes patients.

Aim Correlation of salivary sodium, potassium and glucose levels with severity of periodontitis in diabetic patients.  Materials and Methods Study group consists of 60 patients in which 20 were known diabetic patients with periodontitis in group I,20 patients with periodontitis and without diabetes mellitus in group II,20 non-diabetic patients without periodontitis in group III.  Results In this study elevation of salivary glucose in diabetic with periodontitis and periodontitis groups was observed when compared to control group. Elevation of salivary sodium and potassium were also observed when compared to control group. There was no co-relation observed in salivary glucose levels in diabetic with periodontitis and periodontitis groups. Significant association of periodontal index with elevated HbA1c levels was observed. Also significant co-relation between periodontal index and elevated salivary potassium in diabetic group with periodontitis was observed .Inverse relation was seen in between salivary sodium, periodontal index and salivary sodium in periodontitis group And there was no correlation observed between periodontal index and salivary glucose levels in all the groups. Radiovisiography (RVG) showed more than 3mm of bone loss in diabetic group with periodontitis.  Conclusion Our study showed that in diabetic patients with periodontitis variations in the levels of salivary sodium, potassium and glucose have a significant association with periodontal disease and saliva can be used as reliable diagnostic tool for the assessment of the same.

Fasting salivary glucose levels is not a better measure for identifying diabetes mellitus than serum or capillary blood glucose levels: comparison in a Ghanaian population

Background. To investigate the relationships among blood glucose, mixed saliva glucose, and parotid glucose in type 2 diabetes patients and to evaluate the diagnostic and monitoring value of salivary gland glucose in patients with type 2 diabetes (type 2DM). Material and Methods. Thirty patients with type 2DM and 30 healthy age- and sex-matched individuals were included in this study. Glucose levels in unstimulated mixed saliva and in unstimulated parotid saliva were measured by the glucose oxidase peroxidase method. Results. The blood glucose and parotid salivary glucose levels in type 2DM patients were significantly higher than those in the controls (P < 0.05). The blood glucose, parotid salivary glucose, and mixed salivary glucose were 7.46 ± 1.44 mmol/L, 0.18 ± 0.19 mmol/L, and 3.17 × 10−2 ± 2.84 × 10−2 mmol/L, respectively, in the type 2DM group; the corresponding glucose levels in the control group were 5.56 ± 0.71 mmol/L, 7.70 × 10−2 ± 6.02 × 10−2 mmol/L, and 3.47 × 10−2 ± 2.79 × 10−2 mmol/L. The parotid salivary and blood glucose levels in type 2DM patients were strongly correlated; the linear regression equation for blood glucose and parotid salivary glucose was Y = 6.267X + 6.360, with r = 0.810. However, mixed salivary glucose levels were not significantly different in the type 2 diabetes group compared with the control group. Conclusion. Our results suggest that parotid salivary glucose has potential as a biomarker to monitor type 2DM and as a painless, noninvasive method for the management of type 2DM.

Background and introductionDiabetes mellitus is a common systemic disease in nearly all countries. Its prevalence has been increasing. Thus, early detection and control of this disorder are urgent tasks. The average blood glucose, salivary glucose, and glycosylated hemoglobin (HbA1c) levels must be estimated.Aim and objectiveThis study aimed to assess oral manifestations of type 2 diabetes mellitus in relation to HbA1c and compare glucose levels in the saliva and blood.Materials and methodsThis study examined 60 patients with diabetes who were visiting the Department of Oral Medicine and Radiology as well as the Department of Medicine at Vinayaka Mission’s Sankarachariyar Dental College, Salem, Tamil Nadu, India. In all patients, the blood glucose, saliva glucose, and HbA1c levels were estimated.Results and statistical analysisThe patients (aged 40-60 years) have type 2 diabetes mellitus; among them, patients aged 56-60 years were predominant. In the Pearson correlation analysis, a positive correlation was obtained in random blood glucose, salivary glucose, and HbA1c levels. The p-value was 0.001**, which indicated significance.ConclusionThis study revealed a clear-cut correlation between blood and salivary glucose levels. Thus, salivary glucose levels can very well become a substitute for blood glucose levels. If the estimated salivary glucose level is used in practice to estimate glucose levels in patients with diabetes, the use of any invasive procedures may be avoided.

Diabetes mellitus is a noncommunicable disease with a rising prevalence worldwide and in developing countries. The most commonly used diagnostic biofluid for detection of glucose levels is blood, but sample collection is an invasive and painful procedure. Thus, there arises a need for a noninvasive and painless technique to detect glucose levels. The objectives of the present study were to estimate the glucose levels of saliva, to assess if any significant correlation existed between the serum and salivary glucose levels, and to correlate salivary glucose levels with regard to duration of diabetes, age, and gender. In the present study, serum and salivary glucose levels of 200 subjects (100 diabetic subjects and 100 nondiabetic subjects) were estimated by glucose oxidase method. Glycosylated hemoglobin levels were also measured in randomly selected 40 diabetic subjects. The findings of present study revealed a significant correlation between salivary and serum glucose levels in both diabetic and nondiabetic subjects. No significant relationship was observed between salivary glucose levels and gender or age in both diabetics and nondiabetics and between salivary glucose levels and duration of diabetes in diabetics. On the basis of the findings, it was concluded that salivary glucose levels could serve as a potentially noninvasive adjunct to monitor glycemic control in diabetic patients.

Introduction: There are contradictory reports on using salivary glucose in diagnosis of diabetes mellitus. This study has made an attempt to estimate the salivary glucose levels in diabetic patients with and without complications and correlate them with plasma glucose as a marker of type 2 diabetes mellitus. Method: This was a Cross sectional observational study. Thirty eight type 2 diabetic patients without complications and thirty eight type 2 diabetic patients with either microvascular or macrovascular complications were the subjects of this study. Age and sex-matched normal healthy individuals were included as controls. Plasma and salivary glucose levels were estimated by spectrophotometric method. Results: We observed significantly higher glucose levels in plasma and saliva, in diabetic patients with complications, in comparison to those without complications, and normal healthy controls. There was significant positive correlation between salivary glucose and plasma glucose among all the subjects of the study. Non-linear regression analysis shows exponential relationship between plasma and salivary glucose. Conclusion: Salivary glucose analysis offers noninvasive, sensitive method for assessment of severity of diabetic complications with suitability for repeated sampling. Further studies with larger sample size need to be taken up to establish salivary glucose as a marker of diabetes mellitus. Key words: Plasma glucose, Salivary glucose, Type 2 diabetes mellitus

BackgroundEarly screening of type 2 diabetes mellitus (DM) is essential for improved prognosis and effective delay of clinical complications. However, testing for high glycemia often requires invasive and painful blood testing, limiting its large-scale applicability. We have combined new, unpublished data with published data comparing salivary glucose levels in type 2 DM patients and controls and/or looked at the correlation between salivary glucose and glycemia/HbA1c to systematically review the effectiveness of salivary glucose to estimate glycemia and HbA1c. We further discuss salivary glucose as a biomarker for large-scale screening of diabetes or developing type 2 DM.Methods and FindingsWe conducted a meta-analysis of peer-reviewed published articles that reported data regarding mean salivary glucose levels and/or correlation between salivary glucose levels and glycemia or HbA1c for type 2 DM and non-diabetic individuals and combined them with our own unpublished results. Our global meta-analysis of standardized mean differences on salivary glucose levels shows an overall large positive effect of type 2 DM over salivary glucose (Hedge's g = 1.37). The global correlation coefficient (r) between salivary glucose and glycemia was large (r = 0.49), with subgroups ranging from medium (r = 0.30 in non-diabetics) to very large (r = 0.67 in diabetics). Meta-analysis of the global correlation between salivary glucose and HbA1c showed an overall association of medium strength (r = 0.37).ConclusionsOur systematic review reports an overall meaningful salivary glucose concentration increase in type 2 DM and a significant overall relationship between salivary glucose concentration and associated glycemia/HbA1c values, with the strength of the correlation increasing for higher glycemia/HbA1c values. These results support the potential of salivary glucose levels as a biomarker for type 2 DM, providing a less painful/invasive method for screening type 2 DM, as well as for monitoring blood glucose levels in large cohorts of DM patients.

Aim: The present study was designed to correlate the serum and salivary glucose levels and estimate associated salivary parameters (such as salivary flow rate, pH and buffering capacity) among diabetic and healthy individuals. Settings and Design: 80 patients were included in this study of which 30 patients were uncontrolled diabetics (group I), 30 patients were controlled diabetics (group II) and 20 patients were healthy individuals (group III). Materials and Methods: Salivary and serum glucose levels and salivary flow rate were measured using established methods. Results: The mean serum glucose was higher in group I as compared to group II and group III. In all the groups, salivary glucose levels significantly correlated with serum glucose levels. A statistically significant correlation was also observed between salivary glucose and salivary flow rate in all the three groups. The mean pH values were similar in all the three groups, indicating unaltered salivary buffering capacities. Conclusion: Salivary glucose levels may be used as an alternative and reliable index in diagnosis of diabetes mellitus.

Objective To estimate the association of patient-related demographic, socioeconomic status, physical activity, stress, and dietary factors influencing the relationship between salivary and blood glucose levels in individuals with and without diabetes mellitus (DM). Method This cross-sectional study was conducted on 166 participants with and without DM. Saliva and blood were collected to estimate the glucose levels. Age, gender, occupation, socioeconomic and education level, BMI, hip to waist circumference, stress, dietary pattern, lifestyle, physical activity, family history of diabetes, and type of diabetes were recorded. The association of saliva to predict blood glucose levels was analysed using Spearman Rank Correlation and how these patient-related factors influence the correlation was estimated for future machine learning models. The difference in medians for various groups was calculated using the Mann-Whitney U Test or Kruskal Wallis Test. Results Blood glucose level is not significantly correlated to salivary glucose level. However, a statistically significant difference in the median blood glucose levels for diabetic participants (median = 137) compared to healthy controls (p-value < .05) was noted. The correlation between blood and salivary glucose was more positive for higher levels of glucose (Spearman 0.4). Age, alcohol consumption, monthly wages, intake of vegetables, and socioeconomic status affect blood glucose levels. Conclusion A correlation between saliva and blood glucose levels in healthy individuals was weak. Saliva should only be used as a monitoring tool rather than a diagnostic tool and is more reliable for patients with poorly controlled diabetes mellitus.

Aim: The aim of this study was to investigate the sensitivity of baby birth weight estimation in relation to HbA1c levels of pregnant women diagnosed with pre-gestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM). Material and Methods: 105 patients who met the criteria agreed to participate in our study, of whom 7 were type 1 DM and 32 were type 2 DM. The pregnancy history of the patients who agreed to participate was obtained with a lot of demographic information as well as weight gains during pregnancy, HbA1c and fasting blood glucose levels. Results: Fasting glucose values were measured at 28 and 32 weeks of gestation. The blood glucose values that we measured one hour after satiation and HbA1c were higher in the PDGM group than in the GDM group. There was no significant difference between weight gain and BMI values. We used ROC curve analysis to test the predictive power of fasting and postprandial blood glucose levels or weight gain during pregnancy in our patients with GDM for LGA babies(LGA) (AUC: 0.663, %95 CI [0.526, 0.800], AUC: 0.678, %95 CI [0.540, 0.816], AUC: 0.677, %95 CI [0.548, 0.805], respectively).In addition, ROC analysis was used in evaluating fasting blood glucose measurements, 1-hour postprandial blood glucose measurements, and HbA1c levels to predict LGA.(AUC: 0.889, %95 CI [0.782, 0.996], AUC: 0.893, %95 CI [0.737, 1.000], AUC:0.931, %95 CI [0.807, 1.000], respectively). Conclusion: In both healthy people and pregnant women, it is important to keep blood glucose levels within normal limits. In pregnant women diagnosed with PDGM or GDM, this is even more important as the welfare of the baby is considered. LGA deliveries can be avoided in pregnant women with PDGM by close monitoring of postprandial blood glucose and HbA1c levels. Close monitoring of GWG is also beneficial in the follow-up of pregnant women diagnosed with GDM.