A large, lengthy study has found that long-term statin use is tied to an increased risk of kidney disease. The retrospective study was eight years in length with a median 6.4-year follow-up and involved an analysis of a large number of healthcare insurance plan members. The study appears in the December 1, 2015 American Journal of Cardiology.
According to the study, led by Dr. Tushar Acharya (University of California, San Francisco), statin users were compared with case-matched controls who did not use statins. The study revealed a 30-to-36 percent greater likelihood of developing kidney disease. Senior author Dr. Ishak A Mansi (University of Texas Southwestern, Dallas) noted that patients who take statins should not stop taking them and emphasized, during an interview with Heartwire from Medscape that, “Our study did not examine whether the benefits outweigh the risk (it was not designed for that).” He added that, “… we need further studies specifically focusing on long-term outcomes in primary prevention … the new [ACC] guidelines . . . are projected to increase statin use to many more hundreds of millions of healthy people, and before we do that we better make sure that we are not causing harm,” he warned. “Our paper says to scientists, physicians, funding agencies, [and] policy makers: ‘Watch out, [it] seems that we still do not know enough about the long-term effects of these drugs on [the] overall well-being of patients.”
Dr. Mansi did suggest that, “Clinicians should tell their patients that there may be statin side effects we are not aware of, but there are also benefits that we are aware of.” Medscape.com also noted that clinicians should carefully monitor creatinine levels in patients who are prescribed statins.
The study involved healthcare data from 2003 to 2012 for 30- to 85-year-olds who lived in the San Antonio, Texas area and who were members of Tricare Prime or Tricare Plus insurance plan (for members of the military and their families). The patients were continuously enrolled in the healthcare plan throughout the term of the study; there were no missing data and the overall cohort included 43,438 individuals: 13,626 statin users and 29,812 nonusers. The most commonly prescribed statins follow. A total of 38 percent of statin users received high-density doses and patients took statins for an average of 4.65 years:
• Zocor (simvastatin): 73.5 percent
• Lipitor (atorvastatin): 17.4 percent
• Pravachol (pravastatin: 7 percent
• Crestor (rosuvastatin): 1.7 percent
In the overall cohort involving a comparison between 6,342 statin users and 6,342 non users, statins were tied to a significantly increased risk of different types of kidney disease, including acute and unspecified renal failure; chronic kidney disease; and nephritis, nephrosis, and renal sclerosis, according to Medscape.com. In a healthy cohort, patients who received statins revealed a significantly greater risk of chronic kidney disease.
“The findings of this study, though cautionary, suggest that short-term [randomized controlled trial] may not fully describe long-term adverse effects of statins,” Dr. Acharya and colleagues concluded. Statins lower the risk of cardiovascular disease and cardiovascular death, but “on the other hand, statins increase the risk of incident diabetes and possibly kidney diseases, both of which paradoxically increase long-term morbidity and mortality … further studies, specifically primary-prevention studies, are urgently needed in which the long-term effects of statins on total mortality and total comorbidity indices (not only cardiovascular morbidity) are set as the primary outcomes,” the researchers concluded.