Abstract:
Aims/introduction: We compared the diagnostic performance and correlation
between salivary, serum and capillary blood glucose of diabetes and non-diabetes
patients. Early detection of diabetes mellitus (DM) contributes to the prevention
of complications and management.
Materials and methods: This case-control study was conducted among a total of
138 participants comprising 79 newly diagnosed diabetes patients (cases) and 59
non-diabetes patients (controls). Fasting salivary glucose (FSLG), fasting serum glucose (FSEG) levels and fasting capillary whole blood glucose (FCWBG) level
were assayed for each participant.
Results: The mean FSLG, FSEG and FCWBG levels were significantly higher
among the cases compared to controls (p < 0.0001). There was a significant
mean difference between the levels of FSLG vs. FSEG (p < 0.0001) and FSLG
vs. FCWBG (p < 0.0001) but not levels of FSEG vs. FCWBG (p > 0.05) in
both cases and controls. A positive correlation was observed between FSLG and
FSEG (r ¼ 0.89; p < 0.0001) and FCWBG (r ¼ 0.87; p < 0.0001). At the cut-
off value >6.8 mmol/l for FSEG, a sensitivity of 99%, specificity of 100.0% and
area under the curve (AUC) of 98.8% was observed for predicting DM while a
sensitivity of 80%, specificity of 95% and AUC of 91.0% was observed for
FSLG at a cut-off value >0.5 mmol/l. At the cut-off value >6.9 mmol/l for
FCWBG, a sensitivity of 100.0%, specificity of 100.0% and AUC of 100.0% was
observed for predicting DM.
Conclusion: Fasting salivary glucose (FSLG) levels increased with increasing
blood glucose levels. However, it does not generate enough diagnostic and
predictive accuracy compared to capillary whole blood glucose which less invasive.
