Left Ventricular Mass in Children and Adolescents With Elevated Body Mass Index and Normal Waist Circumference Sudhir Ken Mehta, MD, MBAa,b,* Children and adolescents with elevated body mass index (BMI) who have normal waist circumference (NWC) have a cardiometabolic risk profile similar to normal children. However, there is a lack of adequate information regarding their left ventricular mass (LVM). The present study was undertaken to evaluate LVM in children with elevated BMI with NWC. LVM was assessed by echocardiography in 247 children (age 2 to 19 years) without evidence of heart disease. Data on those who had elevated BMI with NWC (group 1, n [ 80) were compared with matched normal controls with normal BMI who had NWC (group 2, n [ 80) and children with elevated BMI with increased waist circumference (IWC; group 3, n [ 87). Correlations, t tests, and linear regressions were used for statistical testing. LVM in children with elevated BMI with NWC was not significantly different from normal controls (97.6 – 44.4 vs 100.7 – 47.9 g, p [ 0.6713, respectively); however, it was significantly less than that in subjects with elevated BMI who also had IWC (97.6 – 44.4 vs 114.5 – 47.8 g, p [ 0.0193, respectively). Similar to normal controls, those subjects with elevated BMI with NWC had a stronger correlation between LVM and lean body mass (R2 [ 0.86 and 0.86, respectively) than subjects with elevated BMI with IWC (R2 [ 0.75). In conclusion, children with elevated BMI with NWC appear to have a similar LVM profile as children with normal BMI with NWC. The present study emphasizes the importance of measuring waist circumference in children with elevated BMI. Ó 2014 Elsevier Inc. All rights reserved. (Am J Cardiol 2014;113:1054e1057)
This investigation was undertaken to answer 3 basic questions in children and adolescents who have elevated body mass index (BMI), both overweight and obese with normal waist circumference (NWC; the study group): (1) Is the left ventricular mass (LVM) in the “study group” similar to the group with normal BMI of similar age, gender, and waist circumference (WC)? (2) Is the LVM in the study group similar to the group who have elevated BMI and increased waist circumference (IWC)? and (3) How does LVM correlate with BMI, WC, and lean body mass (LBM) in the study group compared with the groups who have normal BMI with NWC and who have elevated BMI with IWC? Methods The total study group comprised 247 subjects. The primary study group of 80 subjects had elevated BMI with NWC (group 1). Their LVM data were compared with an equal number of randomly selected subjects (n ¼ 80) from a pool of 388 subjects with normal BMI who had NWC matched for WC, age, and gender with the help of a software (normal matched controls, group 2). LVM from a Department of Pediatric Cardiology, Cleveland Clinic Children’s, Cleveland, Ohio and bHeart and Vascular Center, Fairview Hospital, Cleveland Clinic Health System, Cleveland, Ohio. Manuscript received September 20, 2013; revised manuscript received and accepted November 23, 2013. See page 1057 for disclosure information. *Corresponding author: Tel: (216) 476-7236; fax: (216) 476-7021. E-mail address: [email protected] (S.K. Mehta).
0002-9149/14/$ - see front matter Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjcard.2013.11.068
subjects in group 1 were also compared with 87 subjects who had elevated BMI with IWC (group 3). The aforementioned groups of 247 patients were selected from a total of 562 subjects, all of whom were evaluated by a pediatric cardiologist at a community hospital from August 2005 to March 2013. Primary referral diagnoses in the studied patients included heart murmur (n ¼ 157), chest pain (n ¼ 115), dizziness and syncope (n ¼ 102), palpitations (n ¼ 80), family history of heart disease (n ¼ 28), abnormal electrocardiogram (n ¼ 22), and miscellaneous other reasons (n ¼ 58). After evaluation, all presenting symptoms were found to be noncardiac (noncardiac chest pain, nonparoxysmal caffeine-related palpitations, and neurocirculatory dizziness and syncope). Heart murmurs were innocent murmurs. Children who had suspected or documented cardiac pathology based on history, clinical evaluation, electrocardiography, and 2-dimensional and Doppler echocardiographies were excluded and were not part of the aforementioned total sample of 562 subjects. Every effort was made to include only subjects with no evidence of cardiac abnormality (n ¼ 562). Elevated BMI was defined as BMI greater than or equal to eighty-fifth percentile for age and gender or BMI 25 kg/m2.1 Conversely, BMI less than eighty-fifth percentile for age and gender was considered a normal BMI. Central obesity was defined as WC more than ninetieth percentile for age, gender, and race (IWC),2 whereas WC less than or equal to ninetieth percentile for age, gender, and race was considered NWC. Of the 562 subjects without evidence of cardiac disease, 80 children were identified has having elevated BMI who had NWC (the study group). Three hundred eighty eight of 562 subjects had normal BMI with NWC: 218 of 388 were www.ajconline.org
Miscellaneous/Waist Circumference in Children
1055
Table 1 Patient demographics, lean body mass (LBM), and left ventricular mass (LVM) index parameters as measured by echocardiography Clinical and Echocardiographic Parameters Age (yrs) Girl:boy Height (cm) Weight (kg) BMI (kg/m2) WC Systolic BP (mm Hg) Diastolic BP (mm Hg) LVM (g) LVM/BSA (g/m2) LVM/height2.7 (g/m2.7) LVM/height1.7 (g/m1.7) LBM (kg) LVM/LBM LBMI (kg/m2) Non-LBMI (kg/m2)
Elevated BMI With NWC (n ¼ 80)
Normal BMI With NWC (n ¼ 80)
Elevated BMI With IWC (n ¼ 87)
p Value
10.3 4.6 31:49 139.1 25 43.8 21 20.9 3.2 70.5 13 106 11 61 7 97.6 44.4 73.8 13.4 38.5 7 52.8 10.7 29.9 15 3.4 0.6 14.2 2.4 6.8 1.3
11.2 4.3 31:49 146.2 27 42.9 19 18.7 2.6 69.3 13 107 12 60 8 100.7 47.9 74.4 15.5 34.4 6.6 49.8 11 31.5 15 3.3 0.6 13.6 2.1 5.1 1.1
11 4 44:43 146.4 24 58.1 25 25.4 4.5 86.9 17 111 12 63 9 114.5 47.8 73.6 14.2 39.6 7.9 57.3 12.6 36.6 16 3.3 0.6 15.9 2.9 9.5 2.1
0.3883 0.2002 0.1118
This investigation was undertaken to answer 3 basic questions in children and adolescents who have elevated body mass index (BMI), both overweight and obese with normal waist circumference (NWC; the study group): (1) Is the left ventricular mass (LVM) in the “study group” similar to the group with normal BMI of similar age, gender, and waist circumference (WC)? (2) Is the LVM in the study group similar to the group who have elevated BMI and increased waist circumference (IWC)? and (3) How does LVM correlate with BMI, WC, and lean body mass (LBM) in the study group compared with the groups who have normal BMI with NWC and who have elevated BMI with IWC? Methods The total study group comprised 247 subjects. The primary study group of 80 subjects had elevated BMI with NWC (group 1). Their LVM data were compared with an equal number of randomly selected subjects (n ¼ 80) from a pool of 388 subjects with normal BMI who had NWC matched for WC, age, and gender with the help of a software (normal matched controls, group 2). LVM from a Department of Pediatric Cardiology, Cleveland Clinic Children’s, Cleveland, Ohio and bHeart and Vascular Center, Fairview Hospital, Cleveland Clinic Health System, Cleveland, Ohio. Manuscript received September 20, 2013; revised manuscript received and accepted November 23, 2013. See page 1057 for disclosure information. *Corresponding author: Tel: (216) 476-7236; fax: (216) 476-7021. E-mail address: [email protected] (S.K. Mehta).
0002-9149/14/$ - see front matter Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjcard.2013.11.068
subjects in group 1 were also compared with 87 subjects who had elevated BMI with IWC (group 3). The aforementioned groups of 247 patients were selected from a total of 562 subjects, all of whom were evaluated by a pediatric cardiologist at a community hospital from August 2005 to March 2013. Primary referral diagnoses in the studied patients included heart murmur (n ¼ 157), chest pain (n ¼ 115), dizziness and syncope (n ¼ 102), palpitations (n ¼ 80), family history of heart disease (n ¼ 28), abnormal electrocardiogram (n ¼ 22), and miscellaneous other reasons (n ¼ 58). After evaluation, all presenting symptoms were found to be noncardiac (noncardiac chest pain, nonparoxysmal caffeine-related palpitations, and neurocirculatory dizziness and syncope). Heart murmurs were innocent murmurs. Children who had suspected or documented cardiac pathology based on history, clinical evaluation, electrocardiography, and 2-dimensional and Doppler echocardiographies were excluded and were not part of the aforementioned total sample of 562 subjects. Every effort was made to include only subjects with no evidence of cardiac abnormality (n ¼ 562). Elevated BMI was defined as BMI greater than or equal to eighty-fifth percentile for age and gender or BMI 25 kg/m2.1 Conversely, BMI less than eighty-fifth percentile for age and gender was considered a normal BMI. Central obesity was defined as WC more than ninetieth percentile for age, gender, and race (IWC),2 whereas WC less than or equal to ninetieth percentile for age, gender, and race was considered NWC. Of the 562 subjects without evidence of cardiac disease, 80 children were identified has having elevated BMI who had NWC (the study group). Three hundred eighty eight of 562 subjects had normal BMI with NWC: 218 of 388 were www.ajconline.org
Miscellaneous/Waist Circumference in Children
1055
Table 1 Patient demographics, lean body mass (LBM), and left ventricular mass (LVM) index parameters as measured by echocardiography Clinical and Echocardiographic Parameters Age (yrs) Girl:boy Height (cm) Weight (kg) BMI (kg/m2) WC Systolic BP (mm Hg) Diastolic BP (mm Hg) LVM (g) LVM/BSA (g/m2) LVM/height2.7 (g/m2.7) LVM/height1.7 (g/m1.7) LBM (kg) LVM/LBM LBMI (kg/m2) Non-LBMI (kg/m2)
Elevated BMI With NWC (n ¼ 80)
Normal BMI With NWC (n ¼ 80)
Elevated BMI With IWC (n ¼ 87)
p Value
10.3 4.6 31:49 139.1 25 43.8 21 20.9 3.2 70.5 13 106 11 61 7 97.6 44.4 73.8 13.4 38.5 7 52.8 10.7 29.9 15 3.4 0.6 14.2 2.4 6.8 1.3
11.2 4.3 31:49 146.2 27 42.9 19 18.7 2.6 69.3 13 107 12 60 8 100.7 47.9 74.4 15.5 34.4 6.6 49.8 11 31.5 15 3.3 0.6 13.6 2.1 5.1 1.1
11 4 44:43 146.4 24 58.1 25 25.4 4.5 86.9 17 111 12 63 9 114.5 47.8 73.6 14.2 39.6 7.9 57.3 12.6 36.6 16 3.3 0.6 15.9 2.9 9.5 2.1
0.3883 0.2002 0.1118
