The study
In the first large scale trial of its kind, researchers studied data from 487 372 users of antihypertensive drugs on the UK Clinical Practice Research Datalink to look at a possible association between concurrent NSAID use and kidney damage. NSAIDs are one of the drug classes known to be associated with an increased risk of kidney damage but the study was set up in response to earlier case reports suggesting more than one antihypertensive could further increase this risk.
The findings
During follow up of almost six years a total of 2215 cases of acute kidney injury were seen. Overall double therapy – a diuretic, ACE inhibitor or ARB plus an NSAID - was not associated with an increased risk. But triple therapy- two antihypertensives plus an NSAID – increased the risk of acute kidney damage by 31%- with the highest risk seen in the first 30 days of use – 82%.
What does it mean for GPs?
The study leaders said although overall there did not seem to be an increased risk of kidney damage with one antihypertensive plus an NSAID – there was a non-significant tendency to an increase risk with a diuretic plus an NSAID not seen with an ACE inhibitor or an ARB. But that overall particular vigilance is needed if a patient needs to be on more than one antihypertensive plus an NSAID- especially in the first month of treatment.
Expert comment
Dr Matt Hughes- cardiology GPSI in Cardiff- said: “This is a particularly interesting study as patients with CKD were excluded- so gives us our best picture yet of the effect of antihypertensives plus NSAIDs on kidney function. So can we say double combinations are “safe”? Probably not- especially with the suggestion of a signal of harm with diuretic plus NSAID – but should certainly be especially vigilant when we have to add a second antihypertensive.”
