April 3, 2013
High-Potency Statins Increase Acute Kidney Injury Risks

Vancouver, British Columbia—High-potency statins significantly increased the risk of hospitalization for acute kidney injury (AKI) compared with low-potency statins, according to an international study.

Results of the observational analysis from Colin R. Dormuth, SCD, of the University of British Columbia and colleagues were published recently in the British Medical Journal.

Using data from seven Canadian provinces and two international databases (United Kingdom and United States) between 1997 and 2008, the researches focused on patients with and without chronic kidney disease (CKD) pulled from two million health records in the Canadian Network for Observational Drug Effect Studies (CNODES).

For the study, the definition of high potency was based on the drugs’ ability to produce a less than or equal to 45% reduction in low-density lipoprotein (LDL). Falling into that category were rosuvastatin at doses of 10 mg or higher, atorvastatin at doses of 20 mg or higher, and simvastatin at doses of 40 mg or more; all others were defined as low potency.

For non-CKD patients under age 65 who were taking low-potency statins, the risks of hospitalization for AKI were 1.2 to 1.4 per thousand patients in British Columbia, Manitoba, and Saskatchewan; 3.5 in Quebec; and 1.0 in the UK database. For those over 65, the rate per thousand patients was 3.1 in Ontario, Nova Scotia, and Alberta and 4.0 in the U.S. database.

Patients with a history of CKD had much higher rates, ranging between 23 and 45 per thousand in the first 6 months after therapy initiation in Canada, to a low of 10 per thousand in the UK database and a maximum of 63 per thousand in the U.S. database.

Not only were high-potency statin users 34% more likely to be hospitalized for AKI compared with low-potency statin users in the first 120 days of treatment, but the risk appeared to be elevated even 2 years after initiation, according to the study.

Those rates were not significantly increased in patients with CKD. According to an estimate in the study, 1,700 non-CKD patients need to be treated with a high-potency statin—instead of a lower-potency drug to reduce cholesterol—in order to cause one additional hospitalization for AKI.

Calling for more studies to determine the relationship between statins and kidney injury, study authors conclude that prescribing high-potency statins is “associated with an increased rate of hospital admission with AKI compared with lower potency statins.” They suggest that the elevated risk be considered when low-potency statins are a viable option.

An accompanying editorial calls for more trials comparing the adverse effects of high- versus low-potency statins. Commentators from the University of Queensland in Australia also urge more research into the causes of kidney injury.

U.S. Pharmacist Social Connect