Objective: Serum lipoprotein(a) [Lp(a)] is strongly associated with atherosclerosis in nondiabetic individuals. To see if atherosclerosis is also associated with serum Lp(a) in both IDDM and NIDDM, we determined the correlation between the toe systolic blood pressure index (TSPI) and serum Lp(a) in tightly controlled diabetic patients without nephropathy.
Research design and methods: Cross-sectional study of 57 IDDM and 35 NIDDM patients. All patients had been under strict glycemic control for at least 6 months. The main outcome measure was TSPI of both lower extremities. In addition, we measured serum Lp(a) and other serum lipids, serum uric acid, total plasma homocysteine, plasma C-peptide, HbA1c, albumin excretion rate, glomerular filtration rate, BMI, abdominal fat distribution, left ventricular hypertrophy, probabilities for cardiovascular disease (CVD), and routine clinical parameters.
Results: TSPI was closely and independently related to serum Lp(a) in IDDM patients: R2 = 0.2999, partial P = 0.0005, and in NIDDM patients: R2 = 0.7326, partial P = 0.0030. TSPI was associated with symptoms of CVD. Median serum Lp(a) concentration was normal in IDDM (45 mg/l [range 10-870]) and NIDDM (72 mg/l [11-803]) patients.
Conclusions: Systemic atherosclerosis measured as the degree of peripheral occlusive arterial disease is strongly associated with serum Lp(a) in both IDDM and NIDDM patients. Serum Lp(a), however, is normal in both types of diabetic patients. Thus, it is indicated that serum Lp(a) should be measured in diabetic patients when assessing their risk profile for atherosclerosis.