Statins can cause liver function derangement. A dose-related rise in serum aminotransferase levels develops in 1% to 3% of people who take statins. A minor (less than two-fold normal) rise in the serum ALT and AST levels (without symptoms) is the most common manifestation of liver injury with these compounds. These elevations usually reverse rapidly with discontinuation of the statin and also reverse if therapy is not interrupted. If your father had normal LFT before starting statins and have increased now - statins could be the cause, however they donot cause serious liver problems. apart from statins, there is a risk of your father having NASH (non alcoholic steatohepatitis). I would advise you to get an ultrasound done. If your father doesnt require statins necessarily you can stop it, if not you can continue them and repeat the LFT after 3 months. If the enzymes are increasing then you need to stop the drug, else you can continue.