LDL lowering trials with initial low LDL Statins and non-statins CHD death, MI, ischemic CVA, or CABG/PTCA Statins Non-statins Cai et al. LDL lowering trials with statins LDL-C level: <1.8 mmol/L New-onset diabetes LDL-C level: 1.8 2.59 mmol/L (70 100 mg/dL) LDL-C level: >2.59 mmol/L Note: LDL levels were converted from mmol/L to mg/dL by multiplying by 38.6 Abbreviations: CABG: coronary artery bypass grafting; CHD: coronary heart disease; CI: confidence interval; CVA: cerebrovascular accident; CVD: cardiovascular disease; LDL-C: low-density lipoprotein cholesterol; mg/dL: milligrams per deciliter; MI: myocardial infarction; mmol/L: millimoles per liter; PTCA: percutaneous transluminal coronary angioplasty; RR: relative risk While the Work Group wishes to emphasize that regular monitoring of lipid levels is not required to monitor therapy effects, there are many reasons a provider may wish to obtain these values. Knowing the LDL level may provide objective data and facilitate shared decision making, identify medication non- adherence, help the provider motivate the patient to follow the treatment regimen, and tailor therapy for patients who are at high risk despite taking statins. Adherence can also be indirectly assessed (e.g., patient report and medication refill frequency). The Work Group acknowledges providers may measure lipid levels in patients of all ages for the reasons enumerated above, to emphasize the importance of lifestyle changes, or to quantify the effect of positive lifestyle changes. These measurements may also be useful in patients under age 40, for whom these guidelines do not make recommendations given the lack of evidence. As this is a Reviewed, New-replaced recommendation, the Work Group systematically reviewed evidence related to this recommendation.[109-113] The Work Group s confidence in the quality of the evidence was very low. 