ObjectiveCarriers of a functional mutation in LCAT, encoding lecithin:cholesterol acyl transferase, are exposed to lifelong low high-density lipoprotein cholesterol (HDL-c) levels. We investigated whether LCAT mutation carriers have increased arterial stiffness as a marker of cardiovascular disease and whether arterial stiffness was associated with carotid wall thickening. MethodsWe assessed 45 carriers of LCAT mutations (mean age ± SD 46 ± 13 yrs) and 45 age-matched controls. Probands referred with established cardiovascular disease were excluded. We measured carotid-fermoral pulse wave velocity (PWV) and carotid artery wall thickening by ultrasound and 3.0 T magnetic resonance imaging. ResultsIn carriers, HDL-c was lower (32 ± 12 vs. 59 ± 16 mg/dl; p < 0.0001) and triglycerides were higher (median 116 [IQR 80–170] vs. 71 [IQR 53–89] mg/dl; p < 0.001) vs. controls. PWV was higher in carriers vs. controls (7.9 ± 2.0 m/s vs. 7.1 ± 1.6 m/s; p < 0.01). This difference retained significance in multivariate analysis including age, sex, mean arterial pressure and body mass index, and after exclusion of carriers and controls with cardiovascular disease. Both in carriers and controls, PWV was correlated with wall thickening of the carotid arteries as assessed by ultrasound (R 0.50, p < 0.001 for carriers and R 0.36, p < 0.04 for controls) and 3.0 T magnetic resonance imaging (R 0.54, p < 0.001 for carriers and R 0.58, p < 0.001 for controls). ConclusionPulse wave velocity is increased in LCAT mutation carriers with low HDL-c and is associated with carotid wall thickening.