Objective: Carotid-femoral pulse wave velocity (cfPWV) was associated with serum parathyroid hormone (PTH) in untreated Chinese. We investigated in the same cohort whether cfPWV, brachial-ankle (baPWV) and heart-brachial (hbPWV) pulse wave velocity (PWV) were associated with rs6127099 (CYP24A1) and rs4074995 (RGS14). A previously published genome-wide association study demonstrated that each additional copy of the T (rs6127099) or G (rs4074995) allele was associated with a 7% or 3% higher serum PTH, respectively.
Methods: In 1601 untreated Chinese patients (mean age, 51.0 years; 51.9% women), we measured cfPWV by tonometry (SphygmoCor) and baPWV and hbPWV by combined oscillometry and plethysmography (VP-2000 PWV/ABI analyser), serum PTH by an immunoassay, and genotypes by the SNapShot method.
Results: cfPWV, baPWV and hbPWV averaged 7.9, 14.6 and 5.5 m/s and serum PTH 65.7 pg/mL. Genotype frequencies were in Hardy-Weinberg equilibrium, amounting to 41.7% (AA), 44.9% (AT) and 13.4% (TT) for rs6127099 and to 70.7% (GG), 26.9% (GA) and 2.3% (AA) for rs4074995. With adjustments applied for sex, age, body mass index, heart rate and season, hbPWV was 0.05 m/s (p = .042) lower with each additional copy of the minor allele (T) of rs6127099. In similarly adjusted analyses of 157 normotensive participants younger than 50 years, cfPWV was 0.32 m/s (p = .004) higher per additional copy of the T allele. Sensitivity analyses additionally accounting for the total-to-HDL serum cholesterol ratio, plasma glucose, glomerular filtration rate and 24 h systolic blood pressure were consistent. No other association of PWV with the genetic variants reached significance.
Conclusions: With an increasing number of rs6127099 T alleles, arterial stiffness, as exemplified by PWV, was lower in all participants in a muscular artery (hbPWV), but higher in young normotensive participants in an elastic artery (cfPWV).
Keywords: Arterial stiffness; blood pressure; clinical genetics; parathyroid hormone; pulse wave velocity.