Sleep apnoea in acromegaly--prevalence, pathogenesis and therapy. Report on two cases

It has long been known, that irregular, heavy snoring and daytime sleepiness are common features of acromegaly. Only recently has the high incidence (30-60%) and clinical relevance of the sleep apnoea underlying these symptoms been recognized. Both diseases have a group of common symptoms and prognostic features: Increased cardiovascular and respiratory mortality, elevated incidence of hypertension, daytime sleepiness, decreased vitality, headaches and depression. These are very prominent in sleep apnoea and often reversible under treatment. In acromegaly their etiology has been widely unexplained and they commonly persist even when human growth hormone (hGH) levels remain normal after operative treatment. We report on 2 patients presenting with excessive daytime sleepiness and severe obstructive sleep apnoea caused by acromegaly. Both had macroglossia and hypertrophy of hypopharyngeal tissues regressive after surgical therapy. The average hGH-levels were 20 and 31 ng/ml before and 3 and 1.7 ng/ml several months after operation respectively. Apnoea indices and minimal oxygen saturations (SO2) were 59/h and 55/h, and 60% and 58% initially and improved postoperatively to 40/h and 50/h, and 72% and 70%. Polysomnographic parameters were normalized by NCPAP-therapy pre- and postoperatively and daytime sleepiness improved dramatically. In one patient the NCPAP-pressure could be decreased postoperatively. Since patients with sleep apnoea have an increased perioperative risk of hypoxia and because transsphenoidal operation and postoperative nasal tamponade were performed, both patients were tracheostomized perioperatively.(ABSTRACT TRUNCATED AT 250 WORDS)