CXCL8 and diabetes mellitus: For the diabetic group, regression analysis between each GCF marker and a variety of factors such as levels of HbA1c, diabetes duration and periodontal parameters, revealed a significant association between the levels of MMP‐8 and IL‐8 (p < 0.001) and between the levels of AGEs and PD (p < 0.004) and only marginally with GI (p < 0.055) (Appendix Table).