Surprisingly, a cohort study didn't show an association between use of nonsteroidal anti-inflammatory drugs and decline in renal function.
Concern about adverse effects — including kidney injury — appropriately deters use of nonsteroidal anti-inflammatory drugs (NSAIDs) in older patients. In this study, researchers used data from a longitudinal U.S. cohort study of 3000 older adults (mean age, 74) to examine associations between NSAID use and renal function. Documentation of NSAID use (over the counter or by prescription) was updated at annual visits. Although median follow-up was only 2 years, changes in glomerular filtration rate (GFR) were estimated through 10 years.
At baseline, mean GFR was 72 mL/minute/1.73 m2 and was not lower in NSAID users than in nonusers; additionally, NSAID users were not more likely to have albuminuria or abnormalities in urinary markers of renal tubular function. During follow-up, rate of decline of GFR did not differ significantly between NSAID users and nonusers. This finding held for both over-the-counter and prescription NSAID use, for people whose baseline GFR was lower than 60 mL/minute, and for users of diuretics or renin-angiotensin system inhibitors. All analyses were adjusted for typical confounders.

COMMENT:
These results surprised the researchers, whose hypothesis was that NSAID use would have detrimental effects on renal function over time. One important limitation is that the database did not include doses and durations of NSAID use. Nevertheless, this study will make me a bit more comfortable prescribing NSAIDs for older patients with arthritis who clearly find that these drugs reduce pain and improve quality of life — as long as their renal function is relatively normal. But I still will monitor renal function regularly and will avoid NSAIDs in patients with standard contraindications.

Dr. Allan S. Brett, MD