We aimed at evaluating the impact of genetic and environmental factors on longitudinal changes in aortic pulse wave velocity (aPWV) and aortic augmentation index (aAIx).
Three hundred and sixty-eight Italian and Hungarian adult twins (214 monozygotic, 154 dizygotic) underwent repeated evaluations of aPWV and aAIx (TensioMed Arteriograph). Within-individual/cross-wave, cross-twin/within-wave and cross-twin/cross-wave correlations were calculated; bivariate Cholesky models were fitted to calculate additive genetic (A), shared environmental (C) and unique environmental (E) components.
For both aPWV and aAIx, cross-twin correlations in monozygotic pairs (r between 0.35 and 0.56) were all significant and always higher than in dizygotic pairs, both at wave 1 and at wave 2. Heritability and unshared environmental proportion of variance at each wave were substantially time-invariant for aPWV (heritability 0.51, 95% CI 0.36–0.63 at wave 1; 0.49, 95% CI 0.34–0.62 at wave 2), whereas for aAIx, we observed a diminished genetic effect (heritability 0.57, 95% CI 0.45–0.67 at wave 1; 0.37, 95% CI 0.21–0.51 at wave 2). Overlapping genetic factors explained a high proportion (0.88, 95% CI 0.61–1.00) of longitudinal covariance for aPWV, and had a relatively lower impact on aAIx (0.55, 95% CI 0.35–0.70). Genetic correlations of aPWV (r = 0.64, 95% CI 0.42–0.85) and aAIx (r = 0.70, 95% CI 0.52–0.87) between waves were lower than 1, suggesting a potential contribution of novel genetic variance on arterial stiffening.
Changes in aPWV and aAIx over time are largely genetically determined. Our results might stimulate further studies on genetic and epigenetic factors influencing the process of vascular ageing.
aDepartment of Medicine, University of Perugia, Perugia
bUnit of Internal Medicine, Terni University Hospital, Terni, Italy
cDepartment of Radiology, Semmelweis University
dHungarian Twin Registry, Budapest, Hungary
eItalian Twin Registry, Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
fCentral European University
gMTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
hVascular and Interventional Radiology Unit, Department of Radiological, Oncological and Anatomo-Pathological Sciences, Sapienza University, Rome
iDepartment of Neurosciences, University of Padua School of Medicine, Padua, Italy
j3rd Department of Internal Medicine, Bajcsy Zsilinszky Hospital, Budapest, Hungary
Correspondence to Dr Giacomo Pucci, Unit of Internal Medicine, Terni University Hospital, Piazzale Tristano di Joannuccio, 1 IT-05100 Terni, Italy. Tel: +39 0744 205201; fax: +39 0744 205201; e-mail: firstname.lastname@example.org
Abbreviations: aAIx, aortic augmentation index; aPWV, aortic pulse wave velocity; BP, blood pressure; EVA, early vascular ageing; HR, heart rate; MAP, mean arterial pressure; NO, nitric oxide
Received 11 December, 2017
Revised 29 May, 2018
Accepted 26 June, 2018