LIPOPROTEIN(A) CONCENTRATION IN DIABETES - RELATIONSHIP TO PROTEINURIA AND DIABETES CONTROL

Diabetic patients are at increased risk of cardiovascular disease, particularly when proteinuria is present. Lipoprotein(a)(Lp(a)] levels were assessed in 37 patients with insulin dependent (IDDM) and in 75 patients with non-insulin dependent (NIDDM) diabetes who showed varying degrees of proteinuria and glycaemic control. Median Lp(a) in 1 12 diabetic patients was significantly greater than in 116 healthy controls (113 vs 48 mg/L; p < 0.01). 86 of the patients had first morning urine albumin concentration < 30 mg/L (normoalbuminuria = NA), 16 patients 30-200 mg/L (microalbuminuria = MA) and ten patients > 200 mg/L (albuminuria = ALB). There was no significant difference in median Lp(a) concentration between the three groups (NA = 108, MA = 163, ALB = 98 mg/L; p > 0.5). No significant difference in median Lp(a) concentration was found between patients with IDDM, NIDDM treated with insulin, or NIDDM treated with oral agents and/or diet (120, 98, 115 mg/L respectively; p > 0.7). When the 86 NA patients were divided on the basis of median fructosamine concentration (357 umol/L), no significant difference was found in median Lp(a) levels between those grouped below or above this median (98 mg/L vs 118 mg/L; p > 0.5). Across all diabetics studied there was no significant correlation present between Lp(a) and urinary protein or glycaemic control. These cross-sectional results suggest that median Lp(a) concentration is increased in both IDDM and NIDDM patients, but, this increase is not related to the degree of proteinuria or short-term glycaemic control.