05.02 Heritability and Intrafamilial Aggregation of Arterial Characteristics

Abstract

Background

We investigated in the same subjects, heritability and familial aggregation of various indexes of arterial stiffness and we partitioned the phenotypic correlation between these traits into shared genetic and environmental components.

Methods

Using a family-based random sampling frame, we recruited 204 parents (mean age, 51.7 years) and 290 offspring (29.4 years) from the population in Cracow, Poland (62 families), Hechtel-Eksel, Belgium (36), and Pilsen, the Czech Republic (50). We measured peripheral pulse pressure (PPp) sphygmomanometrically at the brachial artery; central pulse pressure (PPc), the peripheral (PAIx) and central (CAIx) augmentation indexes by tonometry at the radial artery; and aortic pulse wave velocity (PWV) by tonometry or ultrasound. In multivariate-adjusted analyses, we used the ASSOC and PROC GENMOD procedures as implemented in S.A.G.E. and SAS, respectively.

Results

All traits, with the exception of PPc (P = 0.79) and PWV (P = 0.08), showed significant heritability (P ≤ 0.0001), ranging from 0.37 for PPp to 0.41 for CAIx. The genetic correlation between PWV and the other arterial indexes were significant (ρ_G≥0.29; P<0.0001). The corresponding environmental correlations were only significantly positive for PPp (ρ_E = 0.10, P=0.03). Intrafamilial concordance was significant for all arterial indexes (r≥0.12; P≤0.02), with the exception of PPc (r = -0.007; P = 0.90) in parent-offspring pairs. The sib-sib correlations were also significant for CAIx (r = 0.22; P = 0.001).

Conclusion

The observation in the same group of subjects of significant intrafamilial concordance and heritability of various indexes of arterial stiffness as well as the genetic correlations among arterial phenotypes strongly support the search for shared genetic determinants underlying these traits.

All traits, with the exception of PPc (P=0.79) and PWV (P=0.08), showed significant heritability (P≤0.0001), ranging from 0.37 for PPp to 0.41 for CAIx. The genetic correlation between PWV and the other arterial indexes were significant (ρ_G>0.29; P<0.0001). The corresponding environmental correlations were only significantly positive for PPp (ρ_E = 0.10, P = 0.03). Intrafamilial concordance was significant for all arterial indexes (r≥0.12; P≤0.02), with the exception of PPc (r=-0.007; P = 0.90) in parent-offspring pairs. The sib-sib correlations were also significant for CAIx (r = 0.22; P = 0.001).

The observation in the same group of subjects of significant intrafamilial concordance and heritability of various indexes of arterial stiffness as well as the genetic correlations among arterial phenotypes strongly support the search for shared genetic determinants underlying these traits.