Higher doses of spironolactone, a diuretic (water pill), can prevent the need for dialysis in selected heart failure patients, found a recent study.
The aggressive approach relieved fluid overload safely and effectively in patients who were not responding to conventional diuretics.
Kidney and cardiovascular specialists conducted a pilot study in 19 patients to show that the higher doses of spironolactone, which prevented reabsorption of excess salt in the kidneys and maintained potassium levels, could be used safely in these very-ill patients, who were admitted to the hospital with heart failure exacerbation and don’t respond to conventional diuretics.
Spironolactone is usually given to these types of patients in doses of 25-50 milligrams. In the study published in the journal of Annals of Internal Medicine, the dose was increased to 100 and, at some administrations, even 200 milligrams.
“Heart failure patients come into our care with excessive fluid (salt plus water) on their body, making them short of breath, unable to walk and unable to lie flat. They are miserable because of shortness of breath and distension in their abdomen and legs,” said Shweta Bansal, one of the researchers of the study.
Generally, the treatment is a low-salt diet and diuretics. Furosemide (brand name Lasix) is one of the frequently used medications. When patients are admitted to the hospital, they are monitored on this regimen and usually improve.
But about 15 per cent to 20 per cent of patients do not get better, Dr. Bansal said. They continue to have a fluid overload.
“The reason is they get resistant to the commonly used loop diuretics, and a very high aldosterone level is one of the main reasons for this resistance,” she said.
Kidneys are made up of millions of tiny tubules called nephrons. Nephrons consist of four main segments, including a part, called the loop of Henle, where 20 per cent to 25 per cent of salt reabsorption happens. Loop diuretics target this section.
Spironolactone inhibits the action of aldosterone, a hormone that makes the kidney excrete too much potassium and retain salt in the distal segment, another part of nephrons.
Study participants who didn’t respond to standard therapy were given high-dose spironolactone and monitored for urine output and breathing. “Most of them had a dramatic increase in their urine output and significant improvement in their shortness of breath. We think some patients could avoid needing dialysis if treated in this manner” Dr. Bansal said.