Table 2.
Comparison between FCS and MCS phenotypes.
| Features | FCS | MCS |
|---|---|---|
| Age of onset | Paediatric or Early Adolescence | Adulthood |
| Prevalence | 1:100,000–1,000,000 | 1:600 |
| BMI | Normal BMI | Overweight or obese |
| Contribution of secondary factors | Minor | Major |
| Peak TG | Higher | Relatively lower |
| Lowest TG | Higher | Relatively Lower |
| Acute pancreatitis (prevalence) | Significantly higher | High |
| Multiple acute pancreatitis (prevalence) |
Significantly higher | At the risk of recurrent pancreatitis |
| Hospital admissions | More frequent | Less frequent |
| Lipoprotein disturbance | Increased number of chylomicron particles. Reduced LDL and HDL. |
Increase in the number of TRL, i.e., VLDL, IDL, VLDL, and chylomicron remnant particles. |
| ASCVD | Increased? | Significantly higher than FCS |
| Adverse metabolic phenotype * | Less prevalent | More prevalent |
| Post-heparin LPL activity | Severely reduced | Normal or mildly impaired |
| Inheritance pattern | Autosomal recessive | No discrete pattern |
| Genetic Causes | Presence of two pathogenic variants in LPL, ApoC2, ApoA5, GPIHBP1, LMF1, GPD 1, or CREB3L3 | More than 300 SNVs identified |
| Response to traditional LLT ** | No effect | Mild to moderate effect |
| Treatment | Very-low-fat diet Volanesorsen |
Low-fat diet Addressing secondary factors Variable efficacy with pharmacotherapy |
* BMI ≥ 27 kg/m2, SBP ≥ 130 mmHg, or DBP ≥ 85 mmHg (or treatment for hypertension) and fasting glucose ≥5.6 mmol/L (or diabetes treatment)—the presence of ≥2 of these. ** traditional lipid-lowering drugs, i.e., statins, fibrates, niacin, omega-3 fatty acids. Apo: apolipoprotein; ASCVD: Atherosclerotic cardiovascular disease: BMI: body mass index; CREB3L3: CAMP-responsive element-binding protein 3-like protein 3; FCS: familial chylomicronaemia syndrome; GPD 1: glycerol-3-phosphate dehydrogenase 1; GPIHBP1: glycosylphosphatidylinositol-anchored HDL-binding protein1; HDL: high-density lipoprotein; IDL: Intermediate density lipoproteins; LDL: low-density lipoprotein; LLT: Lipid lowering therapy; LMF1: lipase maturation factor 1; LPL: lipoprotein lipase; MCS: multifactorial chylomicronaemia syndrome; SNV: single nucleotide variant; TG: triglycerides; TRL: triglyceride-rich lipoproteins; VLDL: very-low-density lipoprotein.