Should everyone be taking statins?

Besides reducing the risk of cardiovascular disease (CVD), statins have been linked to benefits for an array of other diseases and conditions, including chronic obstructive pulmonary disease (COPD), chronic kidney disease (CKD), numerous types of cancer, dementia, Alzheimer’s disease, Parkinson’s disease, infections, and even erectile dysfunction. These diverse and favorable findings beg the question: Should everyone be prescribed a statin?

Statins are already among the most widely prescribed drugs, with an estimated 38.6 million adults in the United States (around 12% of the population) prescribed statins as of 2012.

Also, statins don’t have many downsides. They have a relatively safe side-effect profile—the most common complaint is muscle pain (myalgia), experienced by about 10% of patients.

In addition, most statins are inexpensive, with generics as low as $4 a month.

So, why shouldn’t everyone be taking statins? At the very least, why shouldn’t people at low risk for any of the conditions mentioned above take statins?

Because not all the evidence is in yet.

Jury is still out

Investigators have produced overwhelming evidence that statins prevent cardiovascular disease and lower cardiac morbidity and mortality. But the jury is still out, pending further evidence, for non-cardiovascular conditions, according to an international group of authors of a recent review in Annals of Internal Medicine.

The researchers came to this conclusion by reviewing hundreds of meta-analyses of observational and randomized controlled trials of statin use in non-CVD conditions. Among 278 different outcomes that the investigators assessed—including many types of cancer, COPD, dementia, pancreatitis, and others—they found no convincing evidence that statins improved outcomes in these conditions.

Although convincing evidence was lacking, they did find significant evidence for:

• Cancer mortality. Statins were associated with decreased cancer mortality in patients who were already taking them prior to cancer diagnosis. “Clinical guidelines currently do not indicate the use of statins to improve cancer prognosis; however, our results are encouraging enough to merit further investigation,” the authors wrote.

• COPD exacerbation. Statins were linked to fewer exacerbations of COPD. This isn’t a surprise because some evidence shows that statins have potential antiviral and anti-inflammatory effects, and respiratory viral infections are a major cause of COPD exacerbation.

In addition, patients with COPD are prone to comorbid cardiovascular conditions, so statins may have some crossover effect. “However, current data are insufficient to evaluate the association between statins and COPD progression independent of CVD,” the authors wrote. For now, current guidelines don’t specifically recommend statins for COPD, so more research is warranted.

• CKD mortality. Randomized clinical trials showed statins were associated with decreased all-cause mortality in patients with CKD, which supports prescribing statins for these patients to reduce their long-term death risk, the researchers noted. However, the trial data also showed that cardiovascular-related deaths accounted for more than 40% of all deaths in patients with CKD, indicating a major contribution of CVD events.

Nevertheless, “the results of our review support statin use for the primary prevention of death in persons with CKD,” the authors wrote. “However, statins cannot be recommended to slow CKD progression, as this effect is still uncertain.”

In addition, the researchers found “suggestive” evidence of statin use and lower risks for cancer, Alzheimer’s disease, dementia, kidney injury, and infection. But the current evidence doesn’t support prescribing statins for these conditions, the researchers noted.

“We also identified evidence of potential harms from statins, such as induced diabetes and myopathy; however, the evidence had a relatively low level of credibility,” they wrote, adding that the available evidence doesn’t justify withholding statins out of concern for these potential harms.

Overall, this review doesn’t support making any changes to the current clinical recommendations for using statins for non-CVD conditions, the researchers concluded.

In other words, statins are not for everyone. Clinicians should prescribe statins for patients with CVD or high CVD risk, but reserve them in patients with other conditions until more evidence comes to light.

This study received no external funding.

For prescribing statins in patients with CVD or CVD risk, the American College of Cardiology/American Heart Association recently released an updated clinical practice guideline for lowering cholesterol.