Renal disease as a determinant of increased lipoprotein(a) concentrations in diabetic patients

OBJECTIVE - This study examined the hypothesis that kidney function is an i ndependent determinant of lipoprotein(a) [Lp(a)] concentrations in people w ith diabetes. RESEARCH DESIGN AND METHODS - Lp(a) concentrations were measured in plasma samples from 273 type 2 and 223 type 1 diabetic patients recruited from a d iabetes clinic. Kidney function was categorized as normal or pathological a ccording to plasma creatinine levels and creatinine clearance rates. RESULTS - Macroalbuminuria was uniformly associated with significantly rais ed plasma concentrations of Lp(a) regardless of the marker used to identify kidney dysfunction. In contrast, in patients with microalbuminuria, signif icantly raised plasma Lp(a) levels were observed only when creatinine clear ance rates or plasma creatinine levels indicated pathological kidney functi on. These conclusions were independent of diabetes type. CONCLUSIONS - In microalbuminuria and apparently in normoalbuminuria, alter ed kidney function determined by creatinine clearance rates or creatinine l evels appears to be a major determinant of raised Lp(a) levels in both type 1 and type 2 diabetic patients. In contrast, Lp(a) concentrations were uni formly raised in patients with macroalbuminuria.