Endocrine Abstracts

Introduction: Some patients complain of excessive daytime somnolence following pituitary surgery.

Aim: To investigate the presence of obstructive sleep apnoea (OSA) following surgery for non functioning pituitary adenomas (NFPA).

Design and methods: We assessed the prevalence of OSA in 16 routinely selected patients following surgery for NFPA and 13 obese controls attending a tertiary referral centre, by means of the Epworth Sleepiness Score (ESS) and polysomnography. All subjects with sleep apnoea were offered continuous positive airway pressure therapy (CPAP).

Results: The median age in NFPA group was 60 years (IQR: 51, 67) vs 49 years (IQR: 43, 56), p=0.023. Gender: Male: 9/16 (56%) in NFPA vs 7/13(53%) in control group, P=0.89. 15/16 (93%) patients had postoperative hypopituitarism and were on appropriate hormone replacement at the time of evaluation Median ESS was 13 (IQR: 5.25, 36) in NFPA patients and 5.7 (1.75, 18.55) in controls, P=0.04. 14 (87%) NFPA patients had apnoea hypopnoea index (AHI)>5, compared to seven patients (53%) in the obese control group, P=0.043, with 10/15 (66%) with complete anterior pituitary failure. 9/10 (90%) patients with complete anterior pituitary failure were diagnosed from OSA (AHI>5) and were started on CPAP. There were no statistically significant differences in the prevalence of OSA in patients with complete anterior pituitary failure after surgery (90%) compared to those with partial anterior hypopituitarism 4/6 (66%), P=0.24. BMI did not correlate with apnoea hypopnoea index (apnoea – hypopnoea index (AHI), r=−0.17, P=0.54), which suggests that factors other than obesity might explain the prevalence of sleep apnoea after surgery in patients with NFPA.

Conclusions: OSA is common following surgery for NFPA, and is not explainable solely by associated obesity. Polysomnography should be offered to NFPA patients with somnolence or symptoms of OSA.