Fig. 1(A) The comparison of serum adenosine deaminase (ADA) activity levels (means±standard error) between non-diabetic control subjects (Non-DM) and patients with type 2 diabetes mellitus (T2DM). (B) Serum ADA activities show wide variations within each group. aP<0.05 vs. Non-DM subjects.
Fig. 2The comparisons of serum adenosine deaminase (ADA) activity according to level of blood glucose control stratified by HbA1c (A) and fasting plasma glucose (FPG) values (B) in patients with type 2 diabetes mellitus. aP<0.05 vs. the group with HbA1c<7% according to one-way ANOVA test, bP<0.05 vs. the group with FPG <155 mg/dL according to one-way ANOVA test.
Fig. 3The comparisons of (A) adenosine deaminase (ADA) activity and (B) ADA activity adjusted for HbA1c according to the type of antidiabetic treatment that type 2 diabetes mellitus (T2DM) patients had been receiving for at least four weeks before the laboratory tests. The comparisons of (C) ADA activity and (D) ADA activity adjusted for HbA1c between a group on DPP-4 inhibitor (DPP4I)/metformin combination therapy and a group on metformin monotherapy in patients with T2DM. Comparisons of (E) ADA activity and (F) ADA activity adjusted for HbA1c between a group on metformin monotherapy and a group on sulfonylurea monotherapy in patients with T2DM. Vildagliptin 50 mg bid or sitagliptin 50-100 mg daily. Other oral hypoglycemic agents (OHAs), monotherapy or combination therapies including sulfonylurea, metformin, acarbose, or thiazolidinedione; Insulin, any insulin therapy with or without oral antidiabetic agent(s) except for DPP4I. aP<0.05 vs. other OHAs, bP<0.05 vs. the group on metformin monotherapy.
Fig. 4The comparisons of (A) adenosine deaminase (ADA) activity and (B) ADA activity adjusted for HbA1c from before and after the addition of DPP-4 inhibitor (DPP4I) therapy to an existing regimen of metformin monotherapy (2 g/day) in patients with type 2 diabetes mellitus. Vildagliptin 50 mg bid or sitagliptin 50-100 mg daily. ADA activity was measured before and after treatment with vildagliptin 50 mg bid or sitagliptin 50-100 mg daily for at least 8 to 12 weeks.
Fig. 5The comparisons of (A) adenosine deaminase (ADA) activity and (B) ADA activity adjusted for HbA1c between patients with type 2 diabetes mellitus on statin therapy and those not on statin therapy. aP<0.05 vs. no statin.
Table 1Baseline characteristics of the subjects
Table 2The correlations between serum ADA activity and other parameters in all subjects