[Development of blood pressure level over a three years period in non-insulin dependent diabetic subjects according to their microalbuminuria].

UNLABELLED

The purpose of this study is to compare over a three year period blood pressure modifications of type 2 diabetic subjects who suffer of incipient nephropathy to those who remain unharmed of this complication.

PATIENTS AND METHOD

This study population is composed of 83 normotensive (BP < 140/90 mmHg) type 2 diabetic patients not receiving cardio-vascular treatment and unharmed of nephropathy (microalbuminuria inferior to 30 mg/24 hours). An evaluation of the diabetes mellitus is undertaken at a three year interval (A0 and A3). These 83 subjects are distributed in two groups according to the 24 hours microalbuminuria rate at A3. In group I (n = 60), patients whose rate is lower than 30 mg/24 hours and in group II (n = 23), patients whose microalbuminuria is over 30 mg. For these two groups, the following elements are compared at A0 and A3: body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), serum creatinine, cholesterol and triglycerides.

RESULTS

The two groups do not differ in age (57.1 +/- 12 vs 53.8 +/- 16.4 years), duration of diabetes mellitus (11.7 +/- 8.6 vs 13.3 +/- 10.4 years) or body mass index (25.9 +/- 3.8 vs 26.2 +/- 4 kg/m2). At the time of the initial evaluation at A0, none of the studied parameters shows a significant difference between the two populations. Comparison of statements undertaken at A3 shows that blood pressure of Group II patients is higher than in group I, but the difference is only significant for systolic blood pressure (132 +/- 12 vs 139 +/- 11 mmHg; p < 0.01). The balance of diabetes mellitus, serum creatinine and lipid levels do not differ between these two groups. The blood pressure level of Group I doesn't differ significantly at A0 and A3 (128 +/- 11 vs 132 +/- 12 mmHg for SBP; 77 +/- 9 vs 78 +/- 7 mmHg for DBP). On the contrary, patients who develop a nephropathy see their blood pressure increase, but only SBP has a significant risk (128 +/- 12 vs 139 +/- 11 mmHg; p < 0.01). Apparition of a microalbuminuria and increase of blood pressure of Group II are not accompanied by a significant variation of serum creatinine.

CONCLUSION

This study shows that for normotensive type 2 diabetic patients the transition from normo to microalbuminuria is associated with increases in systollic blood pressure. This blood pressure modification occur early, contemporary of the apparition of microalbuminuria, but relationship of causality between this two factors remains to be specified.