Blood pressure by 24 h ambulatory recordings in type 2 (non-insulin dependent) diabetics. Relationship to urinary albumin excretion.

The relationship between blood pressure and microalbuminuria, both associated with cardiovascular disease and death, is sparsely studied in Type 2 (non-insulin-dependent) diabetes, and results may be interfered by the phenomenon of "white-coat-hypertension". We therefore investigated blood pressure by 24h ambulatory recordings (oscillometry) and examined whether blood pressure related to the level of urinary albumin excretion rate (UAER) by synchronous 24h collections. Seventeen diabetics (50-75 years of age) with microalbuminuria (15 less than UAER less than 200 micrograms/min) (DM), 15 with normal urinary albumin excretion (DN) and 10 healthy controls (C) participated. All groups were of comparable sex, age degree of obesity and had normal serum creatinine, and the groups of diabetics were of similar known duration, glycemic control and frequency of antihypertensive treatment. Blood pressures measured at the clinic were significantly higher (p less than 0.01) than 24h recordings. An average systolic pressure of 142 +/- 11 mmHg in DN was increased (p less than 0.01) as compared to C: 130 +/- 10 mmHg, but no further increase was seen in DM: 146 +/- 19 mmHg. Diastolic pressures were not different among the groups (C: 77 +/- 8 mmHg, DN: 80 +/- 11 mmHg, DM: 79 +/- 9 mmHg). Average 24h systolic pressure correlated to the UAER r = 0.61, p = 0.009 in DM, whereas not in DN. By the present method we found isolated systolic hypertension in Type 2 diabetes which may express "vascular stiffness". There was, however, no further rise in blood pressure in patients with microalbuminuria, but in these patients albuminuria may be pressure dependent and/or expressive of vascular pathology.