Body Mass Index and Sexual Maturation in Adolescent Patients with Sickle Cell Anaemia
AbstractBackground: Sickle cell anaemia (SCA) is associated with delayed sexual maturation. The Body Mass Index (BMI) or Quetelets Index is closely linked to events of puberty in normal children. We have so far, found no reports on studies on the relationship between BMI and puberty in patients with SCA.
Objectives: To evaluate sexual maturation in patients with SCA, and determine the influence of BMI on the onset of sexual maturation.
Design: A cross-sectional study carried out in Port Harcourt, Rivers State, from June 1999 to June 2000.
Patients and Methods: One hundred and twenty four adolescents with SCA as well as the same number of matched normal controls were evaluated. A structured questionnaire was used to obtain information on personal data and determinants of socio-economic class. Weight, height (HT) and BMI were obtained and sexual maturation assessed.
Results: Fifty-seven (46.0 percent) males and 67 (54.0 percent) females with SCA as well as their matched controls were evaluated. The mean age at onset of sexual maturation was 14.6±1.4 years for males with SCA and 12.1±1.3 years for the controls. Among the females, this was 14. 2±1.7 years for the patients and 11.4±0.8 years for the controls. The observed differences were statistically significant (P<0.05). The average BMI of SCA patients in Sex Maturity Rating (SMR) 2 was also significantly higher (P<0.05) than the average values in SMR 1 for both sexes.
Conclusion: Sexual maturation is delayed in patients with SCA compared to matched controls. The average BMI obtained at onset of sexual maturation (SMR 2) is significantly higher than values obtained in the prepubertal stages (SMR 1) in both sexes. This suggests that, regardless of chronological age, some increase in body fat and size, as reflected in BMI, is associated with onset of sexual maturation in patients with SCA.
Key Words: Sexual maturation, Puberty, Sickle cell anaemia, Body Mass Index, Sex Maturity Ratings.
Nigerian Journal of Paediatrics 2003; 30:39-44.