Pulmonary Hypertension in Apparently Healthy Children in Southern Nigeria.

Objective: To determine the severity and prevalence of pulmonary hypertension and its relationship with age and body mass index (BMI) in healthy children.

Study Design: Observational study.

Place And Duration Of Study: University of Nigeria Teaching Hospital Ituku-Ozalla Enugu, Lagos State University Teaching Hospital, Niger Delta University Teaching Hospital, Bayelsa and Blessed Children Hospital Enugu from January 2010 to December 2019.

Methodology: Four hundred and seventy (470) apparently healthy children aged 1 to 17 years underwent Doppler echocardiographic studies. Their tricuspid regurgitation velocity (TRV) was measured with continuous wave Doppler. Pulmonary artery systolic pressure (PASP) was estimated using the Bernoulli equation. Elevated PASP were determined at PASP ≥35/mmHg. Values were compared against age and BMI.

Results: The mean age was 7.9 ± 3.3 years. Four hundred and fifty-nine subjects (97.7%) had normal PASP while 11 (2.3%) had elevated PASP. Those with elevated PASP had a significantly higher mean TRV of 2.7 ± 0.22 cm/s (95% CI; 2.55-2.85) vs TRV of 1.56 ± 0.43cm/s (95% CI; 1.52-1.60) and higher mean PASP of 39.27±4.89 mmHg (95% CI; 35.99-42.56) vs 20.45 ± 5.34 mHg (95% CI; 19.96-20.94) (p=0.001). Though majority of the children had appropriate weight for ages, those with elevated PASP had a significantly greater weight than those with normal PASP (p<0.001). There was a weak positive correlation of PASP with age (r=0.16) and BMI in normal weight (r=0.08). Obese children had a negative correlation value(r=-0.13). A weak negative correlation of PASP with BMI was seen in underweight (r=-0.17 and overweight (r=-0.73) children (p>0.05).

Conclusion: The mean pulmonary artery systolic pressure in the studied apparently healthy Nigerian children was 20.45± 5.34/ mmHg. The frequency of elevated PASP was 2.3%, commoner in children with higher BMI. Age and body mass index are not optimal predictors of PASP. Key Words: Pulmonary artery systolic pressure, Children, Pulmonary hypertension, Echocardiography.