To evaluate change both in lipoprotein(a) [Lp(a)] and lipid levels in other lipoproteins in non-insulin-dependent diabetes mellitus (NIDDM) after short-term improvement of glycemie control.
We compared Lp(a) levels in 210 NIDDM patients with those in 46 control subjects and evaluated the relationship between glycemie control and Lp(a) levels in diabetic patients. In addition, changes in Lp(a) levels and lipid levels were assessed after the improvement of glycemie control in 54 poorly controlled NIDDM patients.
In NIDDM, Lp(a) levels in all patients, 62 patients with HbA1c <6.0%, and 75 patients with HbA1c between 6.0 and 8.0%, were significantly higher than those in control subjects (19.1 [1.7-106.6], 19.2 [6.0-106.6], and 20.3 [2.7-75.3] vs. 15.4 [2.0-61.7] mg/dl, median [range], P < 0.05). Lp(a) levels in 73 patients with HbA1c of ≥8.0% (18.7 [1.7-58.8] mg/dl) were not significantly different from those in control subjects. After glycemie control, lipid levels in plasma and in other lipoproteins fell significantly, but Lp(a) did not change (from 18.3 [1.7-58.8] to 18.4 [6.6-95.3] mg/dl). Changes in lipid levels, including Lp(a), did not correlate with those in fasting plasma glucose or HbAlc.
These results suggest that elevated Lp(a) levels do not reflect poor glycemie control and that Lp(a) levels are independent of lipid levels in other lipoproteins after improved glycemie control in NIDDM.