CARDIOVASCULAR RISK-FACTORS IN DIABETIC N EPHROPATHY

Background: Diabetic nephropathy is associated with increased cardiova scular mortality. This may be contributed to by changes in plasma lipi ds, fibrinogen and hemorheology. Cardiovascular autonomic dysfunction, which is related to an increased incidence of arrhythmic death, may a lso play a role. Patients and Methods: Therefore, we investigated in 5 8 IDDM-patients with none (n = 28), incipient (albuminuria 30 to 300 m g/day, n = 11) and overt clinical nephropathy (albuminuria > 300 mg/da y, n = 19) plasma concentrations of lipoproteins and fibrinogen, plasm a viscosity, erythrocyte aggregation and erythrocyte rigidity. Assessm ents of neuropathy included tibial nerve motor conduction velocity, pe rception of vibration, beat-to-beat variation during rest and during f orced respiration, heart-rate response to Valsalva maneuver and heart- rate response to standing (30:15). Results: Patients with clinical ove rt nephropathy had, compared to those without nephropathy, significant ly higher concentrations of LDL-cholesterol, triglycerides and fibrino gen, significantly lower concentrations of HDL-cholesterol and signifi cantly higher plasma viscosity, erythrocyte aggregability and erythroc yte rigidity. Regarding the assessments of neuropathy we found in pati ents with nephropathy, compared to those without nephropathy, signific antly reduced tibial nerve motor conduction velocity, reduced percepti on of vibration thresholds and reduced heart rate variability during r est, during forced respiration, in response to Valsalva maneuver and i n response to standing. In diabetic patients with microalbuminuria ery throcyte aggregability and erythrocyte rigidity were significantly hig her and heart rate variability during rest was significantly lower tha n in patients without nephropathy. Conclusion: In clinical overt nephr opathy there is an aggregation of different cardiovascular risk factor s, namely, disturbances in lipoprotein concentrations, increased fibri nogen concentration and disturbances in hemorheology. Furthermore mark ed deterioration in peripheral and autonomic cardial nerve function in these patients is evident accounting for a part of the greatly increa sed cardiovascular mortality of these patients.