A History of Asthma From Childhood and Left Ventricular Mass in Asymptomatic Young Adults: The Bogalusa Heart Study

Abstract

Objectives: This study aimed to examine whether a history of asthma from childhood is associated with left ventricular (LV) mass in adulthood.

Background: Asthma has been related to various cardiovascular risk factors affecting LV hypertrophy. The authors saw a need for a prospective study to analyze the relationship between a history of asthma from childhood and markers of LV mass among asymptomatic young adults.

Methods: Prospective analyses were performed among 1,118 Bogalusa Heart Study participants (average age at follow-up 36.7 ± 5.1 years), with a baseline history of self-reported asthma collected since childhood (average age at baseline 26.8 ± 10.1 years). LV mass (g) was assessed using 2-dimensional guided M-mode echocardiography and was indexed for body height (m^2.7) as LV mass index (LVMI; g/m^2.7). A multivariate linear mixed model was fitted for the repeated measures.

Results: After an average of 10.4 ± 7.5 years of follow-up, participants with a history of asthma from childhood had a greater LV mass (167.6 vs. 156.9; p = 0.01) and LVMI (40.7 vs. 37.7; p < 0.01) with adjustment for age, sex, race, smoking status, antihypertensive medication, heart rate, and systolic blood pressure (SBP). The difference of LVMI between group with asthma and the group without asthma remained significant after additional adjustment for body mass index (39.0 vs. 37.1; p = 0.03) and high-sensitivity C-reactive protein (38.4 vs. 36.6; p = 0.04). In addition, the authors found significant interactions between SBP and asthma on LV mass and LVMI (p for interaction <0.01, respectively). The associations between asthma and LV measures appeared to be stronger among pre-hypertensive and hypertensive participants (SBP ≥130 mm Hg) compared with participants with normal SBP (<130 mm Hg) (regression coefficient: 39.5 vs. 2.3 for LV mass and 9.0 vs. 0.9 for LVMI).

Conclusions: The findings of this study indicate that a history of asthma is associated with higher LVMI, and this association is stronger among participants with pre-hypertension and hypertension.

Keywords: asthma; left ventricular mass; pre-hypertension.

Figure 1. Interaction of asthma with SBP on left ventricular mass

Adjusted means and 95% confident intervals of heart subclinical biomarkers were calculated using mixed regression models. Models controlled for age, gender (male/female), race (black/white), smoking status (current smokers/non-current smokers), antihypertensive medicine (Yes/No/Missing, using “No” as reference), and heart rate (beats per min), hsCRP (mg/L), and examine survey circles as fixed effects, as well as individual ID as random effects. β was the regression coefficient of asthma in stratified SBP level or smoking status groups, followed by its p values for statistical significance. P for interaction term was given by including the interaction term in the mixed model.)