MMP9 and diabetes mellitus: The study was unable to establish a correlation between the HbA1c levels in diabetics and the serum MMP-9 levels. Nine patients with diabetes mellitus had a HbA1c in excess of 10%, of whom seven had a serum MMP-9 in excess of 20 ng/ml (Table 3). However, this had no statistical significance, and the study was unable to establish a correlation between higher HbA1c levels and serum MMP-9 values.