Ambulatory pulse pressure, decreased nocturnal blood pressure reduction and progression of nephropathy in type 2 diabetic patients.
OBJECTIVE
We followed type 2 diabetic patients over a long period to evaluate the predictive value of ambulatory pulse pressure (PP) and decreased nocturnal BP reduction (non-dipping) for nephropathy progression.


METHODS
Type 2 diabetic patients (n = 112) were followed for an average of 9.5 (range 0.5-14.5) years. At baseline, all patients underwent 24 h ambulatory BP measurement. Urinary albumin excretion rate was evaluated by three urinary albumin:creatinine ratio measurements at baseline and follow-up.


RESULTS
At baseline, patients who subsequently progressed to a more advanced nephropathy stage (n = 35) had reduced diastolic night/day BP variation and higher 24 h systolic BP and PP values; they also had more advanced nephropathy and were more likely to smoke than those with no progression of nephropathy (n = 77). In a Cox regression analysis, independent predictors of nephropathy progression were 24 h PP (p < 0.01), diastolic night:day BP ratio (p = 0.02) and smoking (p = 0.02). The adjusted hazards ratio (95% CI) for each mmHg increment in 24 h PP was 1.04 (1.01-1.07), whereas the adjusted hazards ratio (95% CI) for each 1% increase in diastolic night:day BP ratio was 1.06 (1.01-1.11). Only one of 33 patients (3.0%) with both a diastolic night:day BP ratio and a 24 h PP below the median progressed, whereas 17 of 32 patients (53.1%) with both a diastolic night:day BP ratio and a 24 h PP equal to or above the median progressed to a more advanced nephropathy stage (p < 0.001).


CONCLUSIONS
Ambulatory PP, impaired nocturnal BP decline and smoking are strong, independent predictors of nephropathy progression in type 2 diabetic patients.
Knudsen
S T
ST
Medical Department M (Diabetes and Endocrinology), Aarhus University Hospital, Nørrebrogade 44, 8000, Aarhus C, Denmark. stk@dadlnet.dk
Laugesen
E
E
Hansen
K W
KW
Bek
T
T
Mogensen
C E
CE
Poulsen
P L
PL
D017668:Age of Onset; D000368:Aged; D000419:Albuminuria; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D001794:Blood Pressure / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D002940:Circadian Rhythm; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology* / Q000652:urine; D003928:Diabetic Nephropathies / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000379:methods; D011674:Pulse; D012044:Regression Analysis
D000806:Angiotensin-Converting Enzyme Inhibitors; D002121:Calcium Channel Blockers; D007004:Hypoglycemic Agents; D003404:Creatinine