Publications of Pucci G

Genetic and environmental determinants of longitudinal stability of arterial stiffness and wave reflection. A twin study

Background: 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). Method: 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. Results: 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. Conclusion: 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.

Vertebral artery diameter and flow: nature or nurture

BACKGROUND AND PURPOSE In contrast with the carotid arteries, the vertebral arteries (VAs) show considerable variation in length, caliber, and vessel course. This study investigated whether the variation in diameter and flow characteristics of the VAs might be inherited. METHODS A total of 172 Italian twins from Padua, Perugia, and Terni (54 monozygotic, 32 dizygotic) recruited from the Italian Twin Registry underwent B‐mode and pulsed‐wave Doppler ultrasound assessment of their VAs. VA diameters, peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at the level of a horizontal V2 segment. Univariate quantitative genetic modeling was performed. RESULTS Fourteen percent of the sample had VA hypoplasia. Within pair correlation in monozygotic twins was higher than in dizygotics (.552 vs. .229) for VA diameter. Age‐ and sex‐adjusted genetic effect, under the most parsimonious model, accounted for 54.7% (95% CI: 42.2‐69.1%) of the variance of VA diameter, and unshared environmental effect for 45.3% (95% CI: 30.9‐57.8%). No heritability was found for the PSV of VA, but shared (34.1%; 95% CI: 16.7‐53.7%) and unshared (65.9%; 95% CI: 45.9‐83.1%) environmental factors determined the variance. EDV of VA is moderately genetically influenced (42.4%; 95% CI: 16.1‐64.9%) and also determined by the unshared environment (57.6%; 95% CI: 34.7‐83.7%). CONCLUSIONS The diameter of the VAs is moderately genetically determined. Different factors influence the PSV and EDV of VAs, which may highlight the complex hemodynamic background of VA flow and help to understand the vertebral flow anomalies found by ultrasound.

Association of body mass index with arterial stiffness and blood pressure components: a twin study

Rationale Obesity, blood pressure and arterial stiffness are heritable traits interconnected to each other but their possible common genetic and environmental etiologies are unknown. Methods We studied 228 monozygotic and 150 dizygotic twin pairs aged 18–82 years from Italy, Hungary and the United States, of which 45 monozygotic and 38 dizygotic pairs were discordant for body mass index (BMI; intrapair difference (Δ) in BMI ≥ 3 kg/m2). Blood pressure components and arterial stiffness were measured by TensioMed Arteriograph. Results Hypertension was more prevalent among obese than non-obese individuals (55% vs. 29%, p < 0.001). Age-, sex- and country-adjusted heritability estimates were high for hemodynamic measures (45%–58%) and BMI (78%). According to bivariate Cholesky decomposition, phenotypic correlations between BMI and blood pressure components (r = −0.15 to 0.24, p < 0.05) were largely explained by additive genetic factors (65%–77%) with the remaining explained by the unique environment. When controlling for genetic factors within all monozygotic pairs, ΔBMI was significantly correlated with Δbrachial systolic blood pressure (SBP) and diastolic blood pressure (DBP), Δmean arterial pressure, and Δaortic SBP (r = 0.15–0.17, p < 0.05). For the same measures, heavier co-twins of BMI-discordant monozygotic pairs had significantly higher values than their leaner counterparts (p < 0.05). Conclusion Blood pressure components are moderately correlated with BMI, largely because of shared genetic factors. However, for the association of BMI with brachial SBP and DBP, aortic SBP and mean arterial pressure, acquired, modifiable factors were also found to be important.