Julie Connor is a 71 year old patient who attends following her NHS health check. Results are unremarkable except unfortunately her total cholesterol is raised. Her QRISK score is 13% and after counselling and discussion it is agreed to commence Atorvastatin 20mg for primary prevention of cardiovascular disease. Her bloods are checked within three months and her Liver Function Tests (LFTs) are slightly abnormal. At which level should her statin be stopped ?