Spectral entropy signature of speech perturbation in adult acquired growth hormone deficiency

Approximate entropy (ApEn) adapted to quantify the pattern complexity across the electro-glottogram (EGG) spectral domain characterizes normal male vowel phonation in two groups, a majority group (G1) with high ApEn and a minority group (G2) with low ApEn. Using the ApEn measure of normality a sample of post-treatment male oncology patients with adult onset growth hormone deficiency (GHD) shows distinctive spectral entropy signatures. These are consistent with either disrupted larynx development in relative youth, with high normal-group G1 complexity and elevated pitch, or loss of conscious control in middle age, with low normal group G2 or worse complexity. This is at least initial evidence that speech perturbation may be of value in detecting the adult GHD in oncology.