Popular cholesterol medicine linked to higher kidney risk in study

A large study found that people who began taking the cholesterol-lowering drug rosuvastatin had modestly higher rates of several kidney-related problems than those who started atorvastatin. The differences were more pronounced at higher rosuvastatin doses and among people with advanced kidney disease.

Both drugs belong to the statin class, which is widely prescribed to reduce cholesterol and lower the risk of heart attacks and strokes. The findings point to differences within this major drug category rather than suggesting that cholesterol treatment as a whole harms the kidneys.

Researchers from Johns Hopkins reviewed health records for 947,900 people who started one of the two medications between 2011 and 2019. The study appeared in the Journal of the American Society of Nephrology.

The analysis compared 152,101 new rosuvastatin users with 795,799 new atorvastatin users. Investigators looked for blood in the urine, protein in the urine, and kidney failure severe enough to require treatment such as dialysis or a transplant.

Blood and protein in urine can happen for different reasons, but both can indicate a problem that should be checked. They are separate from kidney failure, so a rise in either outcome does not mean every affected person lost kidney function permanently.

Across a median follow-up of 3.1 years, 2.9% of participants developed blood in the urine and 1% developed protein in the urine. These numbers refer to the full study population, not only rosuvastatin users.

After adjusting for measured differences between the groups, rosuvastatin was associated with an 8% higher relative risk of blood in the urine and a 17% higher relative risk of protein in the urine compared with atorvastatin.

The relative risk of kidney failure needing replacement therapy was 15% higher. These figures describe differences between the two drug groups and do not mean that 15% of rosuvastatin users developed kidney failure.

Higher doses of rosuvastatin were linked to greater risks of blood and protein appearing in urine. The researchers also found a prescribing concern in people whose kidneys were already filtering blood poorly.

In that severe kidney disease group, 44% were given daily doses of 20 or 40 milligrams, above the 10-milligram maximum recommended in the U.S. labeling reviewed in the study. That made dose choice an important part of the findings.

The two medicines showed similar benefits for heart and blood vessel outcomes in the study. However, the treatment was not randomly assigned, and medical records cannot capture every reason a doctor may choose one statin over another.

The results suggest the need for closer attention to kidney function and dosing when comparing statins. They also underline why a medicine must be judged not only by how well it prevents major disease, but also by the effects it may have on other organs.

Source: Johns Hopkins Bloomberg School of Public Health.