Hypertension speeds declining renal function in pre-dialysis patients
MedWire News: Hypertension accelerates a decline in renal function in predialysis patients with advanced kidney disease, research shows.
The decline in renal function resulted in the need for kidney transplantation much sooner in these patients than in those without hypertension, report Moniek de Goeij (Leiden University Medical Center, the Netherlands) and colleagues in the journal BMC Nephrology.
The results support current treatment targets - blood pressure (BP) below 130/80 mmHg in chronic kidney disease (CKD) patients - for patients starting predialysis care, according to the researchers.
High blood pressure is an independent predictor of declining renal function in the general population and is also a risk factor for the progression to kidney disease and end-stage renal disease (ESRD).
In early stage CKD, hypertension has a persistent harmful effect on renal function, and contributes to an acceleration to ESRD.
However, as the researchers point out in the current study, little is known about the effect of hypertension on renal function in patients with advanced kidney disease in predialysis care.
Using data from a follow-up study of patients with chronic kidney disease stages IV-V, the team analyzed data on 508 predialysis patients referred to outpatient clinics.
Of these patients, 89% had systolic and/or diastolic blood pressures greater than 130/80 mmHg, and the majority (92%) were treated with antihypertensive medications at baseline.
The mean decline is the estimated glomerular filtration rate (eGFR) during follow-up was 0.35 ml/min/1.73 m2 per month.
There was statistically significant linear association between increases in blood pressure and a decline in renal function; specifically, for every 10 mmHg increase in systolic blood pressure, eGFR declined an additional 0.04 ml/min/1.73 m2 per month.
For diastolic blood pressure, each 10 mmHg increase resulted in an additional decline in of eGFR of 0.05 ml/min1.73 m2 per month, but the decline in renal function was largest in those with a diastolic blood pressure of at least 100 mmHg.
Also, patients with systolic and diastolic blood pressure greater than the target goal of below 130/80 mmHg were twice as likely to need earlier renal replacement therapy (hazard ratio=2.08) as the 11% of patients who achieved the target goal.
Patients who were below the treatment target were typically prescribed ACE inhibitors and/or diuretics, while those who were above it were treated with calcium antagonists and beta blockers.
Studies are needed to determine if active lowering of blood pressure below the 130/80 mmHg treatment target would result in a slowed progression of declining renal function, state de Goeij and colleagues.
By MedWire Reporters