Evaluation of renal function in elderly heart failure patients on ACE inhibitors.

A total of 187 heart failure patients aged 65-92 years, with pretreatment serum creatinine levels below 200 mumol/l, were monitored for more than 12 months on angiotensin-converting enzyme (ACE) inhibitor therapy. Optimal ACE inhibitor dosage was found in 27% of patients, while a significant deterioration in renal function, characterised by > 20% increase in serum creatinine to > 200 mumol/l, occurred in 25 patients. This was most closely attributable to ACE inhibitor treatment per se (implying co-existence of bilateral renal artery stenosis) in only four cases, including one in whom renal deterioration was reproducible on inadvertent rechallenge. In the other 21, renal deterioration was attributable to diuretic-related blood volume depletion (two cases), nonsteroidal anti-inflammatory drugs (two cases), obstructive uropathy (two cases), preterminal renal shutdown (two cases), and the interaction between diuretic and ACE inhibitor dosage (including long-acting vs short-acting drugs) (13 cases). This study could serve as the basis for future comparisons of ACE-inhibitor-related renal deterioration when the entry requirement is optimal ACE inhibitor dosage.