Racial disparities in electrical and structural cardiac adaptation among adolescent athletes: A systematic review and meta-analysis

Table 1 Participant characteristics

Variable	Number of studies included in analysis	Black vs White athletes (MD, 95%CI)
Age (years)	5	MD = -0.24, 95%CI: -0.69 to 0.21, P = 0.3031, I2 = 92%
Body mass index (kg/m2)	4	MD = -0.22, 95%CI: -0.69 to 0.25, P = 0.3542, I2 = 42%
Body surface area (m2)	5	MD = -0.01, 95%CI: -0.08 to 0.07, P = 0.8754, I2 = 90%
Systolic blood pressure (mmHg)	5	MD = 0.97, 95%CI: -1.20 to 3.04, P = 0.3580, I2 = 78%
Diastolic blood pressure (mmHg)	5	MD = 2.75, 95%CI: 0.35-5.16, P = 0.0248, I2 = 89%
Heart rate (bpm)	5	MD = -1.35, 95%CI: -4.58 to 1.89, P = 0.4141, I2 = 90%

MD: Mean difference.

Table 2 Impact of race on echocardiographic characteristics

Variable	Number of studies included in analysis	Black vs White athletes (MD, 95%CI)
PR interval (millisecond)	2	MD = 17.49, 95%CI: 11.70-23.29, P < 0.0001, I2 = 3.2%
QRS complex duration (millisecond)	4	MD = -7.35, 95%CI: -9.17 to -5.53, P < 0.0001, I2 = 44%
Corrected QT interval (millisecond)	3	MD = -4.95, 95%CI: -7.69 to -2.22, P = 0.0004, I2 = 0%
S1/R5 wave voltages (mm)	3	MD = 11.11, 95%CI: 7.19-15.02, P < 0.0001, I2 = 71%
First degree atrioventricular block	2	OR = 3.84, 95%CI: 2.27-6.50, P < 0.0001, I2 = 0%
Sinus bradycardia	4	OR = 0.79, 95%CI: 0.52-1.20, P = 0.2692, I2 = 85%
ST-segment elevation	5	OR = 4.31, 95%CI: 2.34-7.97, P < 0.0001, I2 = 89%
Ascending concave STE (domed)	2	OR = 1.39, 95%CI: 1.13-1.72, P = 0.0020, I2 = 0%
Ascending convex STE	2	OR = 5.78, 95%CI: 0.31-109.60, P = 0.2424, I2 = 88%
ST-segment depression	2	OR = 3.69, 95%CI: 0.87-15.63, P = 0.0767, I2 = 0%
Inverted T wave	4	OR = 3.80, 95%CI: 1.48-9.72, P = 0.0054, I2 = 77%
Pathologic Q wave	2	OR = 0.40, 95%CI: 0.17-0.96, P = 0.0392, I2 = 0%
Right bundle branch block	4	OR = 0.53, 95%CI: 0.26-1.08, P = 0.0809, I2 = 77%
Left atrium enlargement	4	OR = 3.53, 95%CI: 1.87-6.68, P = 0.0001, I2 = 49%
Left ventricle hypertrophy	5	OR = 2.12, 95%CI: 0.66-6.80, P = 0.2088, I2 = 96%
Right atrium enlargement	2	OR = 6.15, 95%CI: 3.16-11.95, P < 0.0001, I2 = 0%
Right ventricle hypertrophy	2	OR = 2.08, 95%CI: 1.53-2.81, P < 0.0001, I2 = 0%

MD: Mean difference; OR: Odds ratio; STE: ST-segment elevation.

Table 3 Impact of race on echocardiographic characteristics

Variable	Number of studies included in analysis	Black vs White athletes (MD, 95%CI)
A wave	3	MD = -1.50, 95%CI: -3.84 to 0.85, P = 0.2106, I2 = 89%
E wave	2	MD = -5.71, 95%CI: -19.42 to 8.01, P = 0.4148, I2 = 97%
E/A ratio	4	MD = -0.07, 95%CI: -0.11 to -0.03, P = 0.0011, I2 = 0%
LV ejection fraction (%)	3	MD = -0.08, 95%CI: -0.88 to 0.72, P = 0.8412, I2 = 55%
Left atrial diameter (mm)	3	MD = 1.64, 95%CI: 0.16-3.12, P = 0.0296, I2 = 87%
LVEDD (mm)	6	MD = -0.87, 95%CI: -1.58 to -0.17, P = 0.0153, I2 = 87%
LVEDD indexed (mm/m2)	3	MD = -0.36, 95%CI: -1.36 to 0.63, P = 0.4721; I2 = 95%
LV end-diastolic volume (mL)	3	MD = -4.10, 95%CI: 10.48-2.28, P = 0.2080, I2 = 65%
LV end-systolic dimensions (mm)	4	MD = -0.8979, 95%CI: -1.26 to -0.530, P < 0.0001, I2 = 15.6%
LV end-systolic volume (mL)	3	MD = -0.05, 95%CI: -0.70 to 0.60, P = 0.8789, I2 = 0%
LV mass (g)	3	MD = 17.29, 95%CI: -1.05 to 35.62, P = 0.0646, I2 = 82.7%
LV mass indexed (g/m2)	7	MD = 5.02, 95%CI: 1.79-8.26, P = 0.0023, I2 = 75%
Maximal wall thickness	2	MD = 1.05, 95%CI: 0.28-1.83, P = 0.0080, I2 = 86%
Posterior wall thickness (mm)	4	MD = 1.07, 95%CI: 0.36-1.78, P = 0.0033, I2 = 88%
Right ventricle diameter (mm)	2	MD = -0.60, 95%CI: -1.39 to 0.18, P = 0.1324, I2 = 86%
Relative wall thickness	6	MD = 0.03, 95%CI: 0.001-0.06, P = 0.0126, I2 = 86%
Septal wall thickness (mm)	5	MD = 0.85, 95%CI: 0.62-1.07, P < 0.0001, I2 = 83%
Aortic root (mm)	3	MD = 0.30, 95%CI: 0.08-0.53, P = 0.0087, I2 = 0%

LV: Left ventricle; LVEDD: Left ventricle end-diastolic dimensions; MD: Mean difference.