How to Handle Elevated Triglycerides: Life after PROMINENT.

Abstract

Hypertriglyceridaemia (HTG) is a common condition characterised by elevated levels of plasma triglycerides (TG), which are transported in the blood mainly by TG-rich lipoproteins (TRL). Elevated TG levels (150-400 mg/dL) are associated with increased cardiovascular risk. Severe HTG (>880 mg/dL) is associated with a risk of acute pancreatitis only. Randomised clinical trials investigating the clinical benefit of TG-lowering drugs in patients with elevated TG levels have provided conflicting results. Elevated TG levels are only one marker of altered lipid/lipoprotein metabolism and indeed reflect altered concentrations of one or more classes or subfractions of TRL, which in turn may have a different association with CV risk. Fibrates, the drugs most commonly used to treat HTG, provide cardiovascular benefits to only a specific subgroup of patients. The lack of clinical benefit from pemafibrate has emphasised the concept that lowering TG levels is not sufficient to reduce the CV risk unless it is accompanied by a reduction in the number of circulating atherogenic lipoproteins, which can be assessed by determining apolipoprotein B levels. Treatment with omega-3 fatty acids was also ineffective in reducing CV risk, with the exception of icosapent ethyl, which, however, appears to have beneficial effects beyond lipids. New drugs are currently being developed that aim to lower TG levels by targeting apolipoprotein C-III or angiopoietin-like-3, both of which are involved in the metabolism of TGs. TG reduction can be achieved by various drugs, but most of them are ineffective in reducing CV risk. The results of outcome studies on new TG-lowering drugs will clarify whether lowering apoB levels is critical to achieve clinical benefit.