Endocrine Abstracts

Obstructive sleep apnea syndrome (OSAS) is a frequent cardiovascular risk factor in acromegaly. We aimed to retrospectively evaluate sex-related differences in OSAS characteristics and indications of non-invasive ventilation.

Patients and Methods: Thirty-nine adult patients (16 F, 23 M) from two European centers were studied by home sleep apnea test (HSAT) or polysomnography (PSG). OSA was defined by an apnea-hypopnea index (AHI) ≥5/h and analyzed according to age, gender, disease activity, obesity, diabetes mellitus, hypertension and nocturnal continuous positive airway therapy (CPAP). Categorical variables were considered in all cases, whereas, except for pre/post-ventilation AHI, sleep parameters were used in cases defined according to the last International Classification of Sleep Disorders (ICSD-3, 2014) (n=33). Data are expressed as median (range) and statistical analysis based on non-parametric tests.

Results: The median age at diagnosis of acromegaly and at PSG were 48.5 and 52.0 yrs respectively, 25/39 patients (64.1%) had an active disease. OSAS was diagnosed in 36/39 patients (92%) and classified as mild/moderate (≥5 AHI<30) in 12/39 (30.8%) and severe (AHI≥30) in 24/39 patients (61.3%). Severe OSAS tended to be more frequent in M (17/23 vs 7/16 F, P=0.057), who were more frequently advised to start CPAP therapy (21/23 vs 9/15 F, P=0.037). Males had a significantly higher BMI (32.6 vs 28.4 kg/m² P=0.017) and higher prevalence of hypertension (21/23 vs 8/16, P<0.004) despite similar age, GH and IGF1 ULN at the time of diagnostic HSAT/PSG. Overall, AHI was significantly correlated with patients age (ρ=0.36, P=0.023) but not with BMI, and similar in diabetic and non-diabetic patients. By univariate logistic regression, hypertension was the only independent predictor of severe OSAS (P=0.018). Nocturnal cardiorespiratory monitoring. Sleep evaluation was also obtained on CPAP therapy in 17 patients (6 F, 11 M), out of which 10 (58.8%) had controlled acromegaly (3 F, 7 M). A significant decrease in AHI (median – 90.4%, P< 0.001) was observed in all but one patient. OSAS was controlled in 11/17 patients (64.7%; 5/6 F, 6/11 M), including 8/12 with severe OSAS (66.7%), and regardless of hypertension.

Conclusion: OSAS is extremely common in acromegaly, especially using the ICSD-3 criteria, and HSAT may be recommended for routine screening. We found hypertension as a major predictor of severe OSAS, which tended to be more frequent in men. CPAP was found to be effective regardless of OSAS severity and should be encouraged in such patients.