IGF-1-based screening reveals a low prevalence of acromegaly in patients with obstructive sleep apnea.

PURPOSE: Recent epidemiologic studies suggest a high prevalence of acromegaly. The prevalence of obstructive sleep apnea syndrome (OSAS) in acromegaly patients ranges from 47 to 70%. A recent study identified 2 patients with acromegaly among 567 OSAS patients. However, it remains unclear whether screening for acromegaly among OSAS patients is necessary. The aim was to screen for acromegaly among OSAS patients by measuring IGF-1 levels and performing confirmatory tests if necessary.

METHODS: We performed a prospective cross-sectional diagnostic study on the prevalence of acromegaly in patients with OSAS. A total of 507 patients with a confirmed diagnosis of OSAS (357 male, 150 female) were screened.

RESULTS: Seven male and three female patients (1.97% of total) were positively screened for elevated IGF-1 levels. Nine out of ten patients suppressed growth hormone levels during OGTT excluding acromegaly, whereas one individual was identified to have acromegaly according to established criteria (1/507, prevalence 0.2%). Analysis of the data showed no correlation between elevated IGF-1 values and the severity of OSAS or BMI.

CONCLUSIONS: Our data demonstrate a low prevalence of acromegaly in patients with OSAS. Until data from population-based studies is available we suggest restricting screening for acromegaly in OSAS to those patients who have additional clinical features of acromegaly.