Sex- and Age-Related Differences in Electrocardiographic Parameters of Healthy Black Adolescents in Ido/ Osi Local Government Area, Ekiti State, Nigeria

Abstract

Background: Age, sex and racial factors may influence the variations in electrocardiographic (ECG) values in children.

Objective: To describe the sex and age-related differences in ECG variables of apparently healthy black adolescents.

Methods: This cross-sectional study involved 1,194 participants aged 10 to 19 years from selected secondary schools in the Ido-Osi LGA of Ekiti State, Nigeria. A standard resting 12-lead ECG was recorded with the Zoncare ZQ 1203-G ECG machine and interpreted manually. The differences in mean values of ECG variables between males and females were analysed.

Results: The subjects comprised 530 (48.8%) males and 664 (55.6%) females. The overall mean (SD) age was 14.3 ±2.0 with no significant difference in the mean age or frequency of the two sexes. The mean ECG heart rate and QTc were significantly higher in females than in males (p < 0.001 and p = 0.002, respectively). The amplitudes of P, Q, R, S, and T waves (p <0.001) and the sum of S waves in right precordial leads (RPL) and R waves in left precordial leads (LPL) were also higher in males than in females (p < 0.001). The occurrence of sinus tachycardia, notched R and S waves and persistent juvenile T wave pattern was more frequent in females, while J point elevation, J waves and q waves occurred more in males.

Conclusion: Sex - and age - related differences exist in ECG variables of black adolescents. The use of sex - and age - specific reference standards for the interpretation of ECG in black adolescents should be considered.