Longitudinal Analysis of the Pubertal Growth, Body Composition, and Endocrine Development in Young People with and without Diabetes

Ahmed, Marion Lynn (2009). Longitudinal Analysis of the Pubertal Growth, Body Composition, and Endocrine Development in Young People with and without Diabetes. PhD thesis The Open University.

DOI: https://doi.org/10.21954/ou.ro.0000eb17

Abstract

This longitudinal study of children with type 1 diabetes (T1D) and contemporary controls through puberty attempts to elucidate differences in their growth, pubertal development and the relationship with pubertal hormones.

Fifty two T1D prepubertal children aged 7.7- 14.4y and 125 control children aged 8.3 - 11.96y were recruited. Auxology and puberty were assessed and blood samples were obtained 6 monthly until the age of 16 years. Annual bone age was assessed in T1D subjects.

Puberty onset and PHV was later in T1D boys compared to controls, while T1D girls were younger at puberty onset with an advanced bone age and their peak height velocity was earlier compared with controls. Overall compared to the UK references, T1D girls had a reduced peak height velocity whereas the boys had normal pubertal growth.

T1D children had greater increases in BMI during puberty but whereas in the girls this was due to greater acquisition of fat mass, in the boys it related to gains in fat free mass.

Levels of DHEAS, IGF-I, A4, testosterone and oestradiol were lower in T1D boys and girls whereas leptin and SHBG were higher.

The pubertal delay in T1D boys was partially explained by bone age but diabetes presence was also contributory. The earlier puberty, advanced pubertal bone age and reduced height gain in T1D girls were associated with complex hormonal changes. The advanced bone age at pubertal onset was not influenced by adrenal hormones but by BMI. Loss in height gain in these girls was related to E2 levels and glycaemic control at the start of puberty.

This study helps clarify some of the relationships between hormonal changes and variation in auxological factors during normal puberty. Differences in these parameters between T1D and control children are only partially explained by endocrine relationships; other factors, relating to T1D including glycaemic control and insulin dose, are important.