Naslov
Relationship between Night/Day Diastolic Blood Pressure Ratio and Microvascular Complications in Normoalbuminuric and Normotensive Patients with Type 1 Diabetes

Autori
Duvnjak, Lea ; Vuckovic, Sandra ; Car, Nikica ; Metelko, Željko

Izvornik
Diabetes (0012-1797) 52 (2003), Suppl 1;

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, kongresno priopcenje, znanstveni

Ključne riječi
Type 1 dibetes; night/day diastolic blood pressure ratio; microvascular complication
(Type 1 diabetes; night/day diastolic blood pressure ratio; microvascular complication)

Sažetak
To determine if a reduced nocturnal fall in diastolic blood pressure (dBP) increases the risk of microvascular complications in normoalbuminuric and normotensive type 1 diabetics, we performed 24 h ambulatory blood pressure (AMBP), 24h urinary albumin excretion (UAE), direct ophtalmoscopy and a battery of cardiovascular reflex tests in 156 patients. They were classified according to night/day diastolic BP ratio > or < 0.9 as dippers (n=118) and non-dippers (n=38) and the groups were similar regarding age, gender, the duration of diabetes, HbA1c and lipid profile. Urinary albumin concentration was determined by an immunoturbidimetric assay. Direct ophtalmoscopy was performed with dilated pupils and retinopathy classified according to the European Protocol. Tests of heart rate variation (HRV) included the coefficient of variation (CV) and the low-frequency (LF), midfrequency (MF) and high-frequency (HF) bands of spectral analysis at rest, HRV during deep breathing (CV, mean circular resultant), Valsalva ratio and maximum/minimum 30:15 ratio. Autonomic neuropathy was characterized as an abnormality of more than two tests. Between the non-dippers and dippers a significant difference in 24h UAE (19.56 &plusmn ; ; ; 4.8 ; 12.3&plusmn ; ; ; 2.5 p< 0.05), prevalence of nonproliferative retinopathy (75% ; 44%, p< 0.05) and autonomic neuropathy (59% ; 24.5%, p< 0, 05) was found. Night/day dBP ratio was inversely related to 24h UAE, retinopathy and autonomic indices (power MF, HF and deep breathing tests (CV, mean circular resultant)). A stepwise multiple regression analysis was performed with night/day dBP ratio as dependent variable and the following variables as possible predictors: duration of diabetes, HbA1c, UAE, power MF, HF, deep breathing tests, retinopathy. Night/day dBP was significantly associated with log UAE (b=0, 10), power MF (b= -0, 17), power HF (b= - 0, 52), deep breathing (b= - 0, 19, beta= 0, 042). In a significant number of normoalbuminuric and normotensive type 1 diabetic patients an impaired night dBP fall is associated with autonomic disfunction and may be relevant to the long term development of microvascular complications.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti, Farmacija

POVEZANOST RADA