Context: Idiopathic intracranial hypertension (IIH) is characterised by elevated intracranial pressure and occurs predominantly in obese premenopausal women. Signs and symptoms of polycystic ovary syndrome (PCOS) often coexist in IIH. Here we compared the androgenic and metabolic phenotypes in IIH, PCOS and simple obesity.
Patients and methods: We studied 25 patients with IIH (mean age 34.4±9.2 years; mean BMI 37.8±5.2 kg/m2), in comparison to 31 women with PCOS and 15 with simple obesity; all three groups were matched for age and BMI. Women with IIH were studied before and after a weight loss intervention (mean BMI change −5.8±3.0 kg/m2). In all participants we performed comprehensive metabolic phenotyping and steroid profiling. Serum androgens were measured by liquid chromatography-tandem mass spectrometry); 24-h urinary steroid excretion was analysed by gas chromatography/mass spectrometry. Urinary steroid profiles were correlated with clinical parameters of IIH severity.
Results: Serum testosterone in IIH was comparable to PCOS and significantly higher than controls (P=0.01). Serum androstenedione was significantly increased in PCOS (P=0.008) but IIH did not differ from controls. Insulin resistance as assessed by HOMA-IR did not differ between IIH and controls; PCOS women had a trend towards significantly higher HOMA-IR values (P=0.08). Total glucocorticoid excretion was significantly higher in IIH compared to controls (P=0.01) and decreased after weight loss (P=0.02). Similarly, the urinary ratio of 5α-THF/THF, a marker of systemic 5α-reductase activity, was significantly increased in IIH compared to controls (P=0.04). The An/Et ratio correlated significantly with baseline markers of ocular papilloedema in IIH (R=0.47, P=0.02).
Conclusion: These results indicate a distinct andro-metabolic signature in IIH, with increased testosterone but normal androstenedione and HOMA-IR values. We propose the new term of andrometabolic syndrome that regularly features androgen excess and obesity and variably presents with additional features such as anovulation (PCOS) and raised intracranial pressure (IIH).