Evaluation of pituitary and thyroid hormones in patients with subarachnoid hemorrhage due to ruptured intracranial aneurysm

Abstract

It is well known that the central nervous system (CNS) influences the pituitary hormone secretions and that diseases of CNS are frequently associated with an altered endocrine function. The aim of this study has been the evaluation of the serum concentrations of the pituitary and thyroid hormones in a series of patients with subarachnoid hemorrhage due to a ruptured cerebral aneurysm. Thirty-five patients (23 females and 12 males), aged 51.9±13.3 years on the mean were admitted. They were evaluated to assess the clinical severity of the subarachnoid hemorrhage by Hunt & Hess scale: nine patients were in the grade I, 14 in the grade II, and 12 in the grade III. Blood samples were obtained between 8:00 and 9:00 a.m. and serum hormones were measured by commercial kits (IRMA or MEIA methods). Cortisol serum levels (normal range (NR) = 5 to 18 µg/dL) were increased in all the patients (mean ± standard deviation = 31.4±12.4 µg/dL). Mean prolactin levels (NR < 20 ng/mL) were 18.6±17.1 ng/mL and five patients (14.2%) had levels higher than normal. FSH and LH levels were normal according to age and sex: men: FSH = 4±2.9 mUI/mL (NR = 1 to 10.5 mUI/mL); LH = 6.1±6.3 mUI/mL (NR = 2 to 12 mUI/mL); premenopausa women: FSH = 2.5±1.5 mUI/mL (NR = 2.4 to 9.3 mUI/mL); LH 3.9±5.1 mUI/mL (NR =2 to 15 mUI/mL); post- menopausal women: FSH = 48.3±18.5 mUI/mL (NR =31 to 134 mUI/mL); LH = 29±13.8 mUI/mL (NR =16 to 64 mUI/mL). Mean TSH levels were 3.9±5.2 µUI/mL (NR =0.5 to 4.7 µUI/mL) and five patients (14.2%) had levels higher than normal. Mean triiodothyronine levels (T3) were 66.4±18.7 ng/dL (NR = 45 to 137 ng/dL) and five patients (14.2%) had levels lower than normal (33.8±9 ng/dL). Mean thyroxine levels (T4) (NR= 4.5 to 12.5 µg/dL) were 7.4±1.7 µg/dL and two patients (5.6%) had levels lower than normal. Thyroglobulin and microsomal antibodies were not detectable. Conclusions: In the first 24 hours following ictus, the hormonal changes may be due to the stress produced by the intracranial bleeding; thyroid hormone alterations suggest that patients with subarachnoid hemorrhage might have an euthyroid sick syndrome.