Cardiac structure and functional alterations in white coat hypertension

172A

POSTERS: Cardiac Structure and Function

AJH–May 2003–VOL. 16, NO. 5, PART 2

P-371 CENTRAL ADIPOSITY SHOWS STRONGER CORRELATION WITH LEFT VENTRICULAR STRUCTURE AND FUNCTION THAN BLOOD PRESSURE IN ADOLESCENTS

P-372 CARDIAC STRUCTURE AND FUNCTIONAL ALTERATIONS IN WHITE COAT HYPERTENSION

Vincent J.B Robinson, Agha J Ahmed, Paule Barbeau, Mark S Litaker, Mathew C Humphries, Gaston Kapuku, Bernard Gutin. Section of Cardiology, Medical College of Georgia, Augusta, GA; Office of Biostatistics and Bioinformatics, Medical College of Georgia, Augusta, GA; Georgia Prevention Institute, Medical College of Georgia, Augusta, GA. Body size and blood pressure are determinants of left ventricular (LV) structure and function. However, the relative contribution of these two factors to LV remodeling in childhood is unclear. Therefore, we assess the relationship between LV measures and body habitus and blood pressure(BP). Subjects (n ⫽ 268) aged 14-18y (white 46%, blacks 54%, males 38%, females 62%) were enrolled. Adiposity measures included body mass index (BMI), percent body fat (%BF), and waist circumference (WC). Echocardiographic measures included LV mass indexed to height2.7(LVM/Ht 2.7), left ventricular posterior wall thickness (LVPWD), interventricular septum thickness (IVSD), left ventricular internal dimension (LVIDD), relative wall thickness (RWT), and midwall fractional shortening (MFS). Systolic BP and diastolic BP were measured. After adjusting for race, sex and their interaction, the table shows: all measures of LV structure and function were significantly correlated with WC(r 0.17-0.42), %BF(r 0.100.36), and BMI(r 0.19-0.51), and all LV measures except RWT and MFS were significantly correlated with SBP(r 0.16-0.22). DBP was not significantly correlated with any of the LV measures. Stepwise regressions were performed, adjusting for race, sex, age, with measures of LV structure and function as the dependent variables, and %BF, WC, and SBP as the predictor variables. WC was the only variable which explained a significant proportion of the variance for all the LV measures (3-19%). %BF explained a significant proportion of the variance only for LVIDD (4%); SBP only for IVSD (1%) and LVPWD (1%). In adolescents, LV structure and function were more highly associated with adiposity measures than with blood pressure, central adiposity more so then overall adiposity. This study suggests that central adiposity is the more potent predictor of unfavorable LV remodeling compared to BP. Key Words: Left ventricular structure and function, Blood pressure, Adiposity

Carlos S Moreira, Paula Alcantara, Cristina Alcantara, Fa´ tima Cerejo, Jose´ M Braz-Nogueira, Luciano Ravara. Medicine III Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal; Medicine III - Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal; Medicine III - Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal; Medicine III - Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal; Medicine III - Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal; Medicine III Lisbon Medicine Faculty, Department of Medicine I, Santa-Maria Hospital, Lisbon, Portugal. Objective: Target organ damage in white coat hypertension (WCH) is still controversial, but treatment is not generally thought to be necessary. We undertook this study to assess whether WCH is associated with any functional or morphological organ damage. Methods: We evaluated 78 subjects (normotensives (NT), WCH, and hypertensives (HT) for cardiac remodelling by Doppler and B-mode echocardiography. Left ventricular mass was calculated according to the formula of Devereux and adjusted for body surface area. The hypertensive patients were under medication. All patients underwent 24h ABPM (90027, Space Labs). WCH defined as office blood pressure ⱖ140/90 mmHg and ambulatory daytime pressures ⬍ 130/80 mmHg. It was used the ANOVA statistical model, with the Scheffe´ ’s multiple comparison test. It was considered statistically significant values of p⬍0,01 (twotailed). Results: WCH had a significantly higher LVMI, CHI, IVRT, IVRT and PIIIP then normotensives, and lower then hypertensives (ANOVA p⬍0.01), and significantly lower E/A index than normotensive and higher than hypertensives. A correlation between PIIIP and LVMI and IVRT was found, r⫽0.61 and r-⫽0.55, respectively (p⬍0.01). Conclusion: This finding could suggest a higher risk of vascular events for the WCH patients, and white coat hypertension could be looked as a cardiovascular risk factor. Key Words: White Coat Hypertension, Left Ventricular Hypertrophy, Target Organ Damage Groups Characteristics

SBP DBP WC %BF BMI

LVM

RWT

MFS

LVPWD

IVSD

LVIDD

0.17* 0.04 0.42* 0.36* 0.51*

0.11 0.06 0.23* 0.19* 0.23*

0.03 0.03 0.17* 0.15* 0.19*

0.21* 0.05 0.39* 0.10* 0.40*

0.22* 0.07 0.38* 0.28* 0.40*

0.16* 0.03 0.29* 0.14* 0.27*

Correlation coefficients among LV parameters, after adjusting for sex, race and interaction. * p⬍0.05

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Age BMI SBP casual DBP casual SBP-ABPM DBP-ABPM Dipper status (%) LVMI(g/m2) RWT E/A IVRT PIIIP

N (34)

WCH (42)

HT (46)

p

47.3 ⫾ 8.7 26.8 ⫾ 1.2 122.3 ⫾ 8.1 71.8 ⫾ 7.1 116.2 ⫾ 7.3 72.3 ⫾ 8.3 100 92.3 ⫾ 15.1 0.36 ⫾ 0.07 1.03 ⫾ 0.22 88.3 ⫾ 10.1 0.32 ⫾ 0.08

48.4 ⫾ 9.2 27.1 ⫾ 1.9 148.3 ⫾ 11.1 93.8 ⫾ 7.9 124.5 ⫾ 10.9 78.2 ⫾ 8.4 96.3 122.0 ⫾ 14.3 0.40 ⫾ 0.09 0.98 ⫾ 9.2 102.0 ⫾ 9.8 0.38 ⫾ 0.11

49.3 ⫾ 10.1 27.3 ⫾ 1.6 150.1 ⫾ 12.1 94.3 ⫾ 6.8 145.3 ⫾ 13.1 87.3 ⫾ 8.1 9.6 146.2 ⫾ 19.3 0.44 ⫾ 0.07 0.94 ⫾ 0.4 112.4 ⫾ 9.1 0.49 ⫾ 0.14

n.s. n.s. ⬍0.01 ⬍0.01 ⬍0.01 ⬍0.01 n.s. ⬍0.01 ⬍0.01 ⬍0.01 ⬍0.01 ⬍0.01

LVMI ⫽ left ventricular mass index; IVRT ⫽ isovolumetric ventricular relaxation time; RWT ⫽ relative wall thickness; PIIIP ⫽ procolagen amino-terminal polypeptide

© 2003 by the American Journal of Hypertension, Ltd. Published by Elsevier Inc.