How often should liver enzymes be routinely measured in patients taking statins?
We recommend a baseline check before starting treatment with a statin, eight weeks after starting a statin or after any dose increase, then if liver function tests (LFTs) are stable, annual checks thereafter. There is broad consensus that alanine aminotransferase and/or aspartate aminotransferase should be checked before starting a statin, and then rechecked one to three months after starting treatment. There is less agreement on how often LFTs should be measured subsequently. Some authorities recommend only annual checks, whereas others recommend checks every eight to 12 weeks during the first year of treatment, followed by annual checks thereafter. The Scottish Intercollegiate Guideline Network recommends a single check after starting and none thereafter if LFTs are normal. Many of the guidelines we reviewed advised or based their recommendations on the monitoring requirements outlined by the manufacturers of the different statins. Data from the largest statin study to date, the hear
