Patients with morbid obesity should not be routinely screened for Cushing's syndrome: Results of retrospective study of patients attending a specialist weight management service

Cushing's syndrome (CS) is a rare condition which results in multi-system involvement and can lead to significant morbidity and mortality. Screening for CS in patients with obesity has been suggested to identify undiagnosed or occult cases. This study was performed to determine whether CS screening is indicated in a tier 3 weight management centre in the UK. A retrospective review of all patients referred to the weight management service between 2013 and 2016 inclusive was undertaken. A final cohort of 569 patients was obtained. Clinic letters and laboratory databases were used to obtain demographic information, patient characteristics and biochemical results. A total of 387 patients were screened using the 1 mg overnight dexamethasone suppression test (ODST) and 182 patients were screened with two 24-hour urinary free cortisol (UFC) collections. A total of 27 patients had an initial abnormal result, of which 16 underwent further testing and had normal results. Six were reviewed and did not demonstrate any clinical features of CS. Five did not attend their clinic appointments but there were neither concerning features within their referrals, nor subsequent diagnoses of CS made. No patients from this cohort were diagnosed with CS. This study does not support routine CS screening of patients affected by severe obesity referred to a specialist tier 3 weight management service. Clinical assessment should be undertaken first and further investigations performed only if deemed necessary.