Influence of albuminuria and glomerular filtration rate on blood pressure response to antihypertensive drug therapy.

Background: Albuminuria and glomerular filtration rate (GFR), two factors linked to kidney and vascular function, may influence longitudinal blood pressure (BP) responses to complex antihypertensive drug regimens.

Methods: We reviewed the clinic records of 459 patients with hypertension in an urban, academic practice.

Results: Mean patient age was 57-years, 89% of patients were African American, and 69% were women. Mean patient systolic/diastolic BP (SBP/DBP) at baseline was 171/98 mmHg while taking an average of 3.3 antihypertensive medications. At baseline, 27% of patients had estimated (e)GFR <60 ml/min/1.73(2), 28% had micro-albuminuria (30-300 mg/g) and 16% had macro-albuminuria (>300 mg/g). The average longitudinal BP decline over the observation period (mean 7.2 visits) was 25/12 mmHg. In adjusted regression models, macro-albuminuria predicted a 10.3 mmHg lesser longitudinal SBP reduction (p < 0.001) and a 7.9 mmHg lesser longitudinal DBP reduction (p < 0.001); similarly eGFR <60 ml/min/1.73(2) predicted an 8.4 mmHg lesser longitudinal SBP reduction (p < 0.001) and a 4.5 lesser longitudinal DBP reduction (p < 0.001). Presence of either micro- or macro-albuminuria, or lower eGFR, also significantly delayed the time to attainment of goal BP.

Conclusions: These data suggest that an attenuated decline in BP in drug-treated hypertensives, resulting in higher average BP levels over the long-term, may mediate a portion of the increased risk of cardiovascular-renal disease linked to elevated urinary albumin excretion and reduced eGFR.