Pathogenesis (development of disease)
The STH deficiency of healthy adults in middle and advanced age, termed somatopause, originates exclusively from the age-related exponential decline in STH secretion (site of synthesis: anterior pituitary) beginning at about age 24.
Etiology (Causes)
Biographic causes
- Genetic burden
- Genetic diseases
- Hemochromatosis (iron storage disease) – genetic disease with autosomal recessive inheritance with increased deposition of iron as a result of increased iron concentration in the blood with tissue damage.
- Genetic diseases
- Age – age-related exponential decline in STH secretion from about the age of 24.
Behavioral causes
- Nutrition
- Consumption of stimulants
- Alcohol – (woman: > 20 g/day; man: > 30 g/day).
- Physical activity
- Physical inactivity
- Psycho-social situation
- Anxiety
- Emotional disturbances
- Stress – acute stress stimulates growth hormone; chronic stress, on the other hand, leads to suppression
- Overweight (BMI ≥ 25; obesity) – especially with android body fat distribution.
- Android body fat distribution, that is, abdominal/visceral, truncal, central body fat (apple type) – there is a high waist circumference or increased waist-to-hip ratio (THQ; waist-to-hip ratio (WHR))When measuring waist circumference according to the International Diabetes Federation guideline (IDF, 2005), the following standard values apply:
- Men < 94 cm
- Women < 80 cm
The German Obesity Society published somewhat more moderate figures for waist circumference in 2006: < 102 cm for men and < 88 cm for women.
Disease-related causes
- Diabetes mellitus – is accompanied by hyperglycemia, which inhibits growth hormone production.
- Hemochromatosis (iron storage disease).
- Hyperthyroidism (hyperthyroidism)
- Hypopituitarism, e.g., due to craniopharyngioma or Sheehan syndrome.
- Insomnia (sleep disorders)
- Liver disease – steatosis hepatis (fatty liver), hepatic fibrosis, condition after hepatitis.
- Adrenal hyperfunction (cortisol suppresses growth hormone).
- Resistance of the liver to somatotropic hormone (STH), which in turn manifests itself in lowered concentrations of circulating IGFs (insulin-like growth factor).
Laboratory diagnoses – laboratory parameters that are considered independent risk factors.
- Hyperglycemia – inhibits growth hormone production, such as in diabetes mellitus.
- Hyperinsulinemia
- Deficiency of steroid hormones (adrenal and ovarian steroid hormones), especially androgens (e.g., andropause).
- Hypertriglyceridemia – increased degradation of triglycerides to free fatty acids (FA) and glycerol → suppression of growth hormone secretion (synonyms: somatotropic hormone (STH), somatotropin) as a feedback response by the free fatty acids (FFS).
Drugs with STH inhibitory effect:
- Aminophylline, theophylline
- Bromocryptine
- Chlorpromazine
- Corticosteroids
- Cyproheptadine
- Ergotamine alkaloids
- Morphine, apomorphine
- Methysergide
- Phenoxybenzamine
- Phentolamine
- Reserpine
- Tolazoline
