Bedside Assessment of Skin-Fold Thickness

Background: The known catabolic effects of glucocorticoid excess on protein metabolism prompted us to devise a method to assess this measure in reproductiveaged females with Cushing's disease. Since collagen protein is a major component of skin, decreased abundance of this protein should cause a reduction in skin-fold thickness. To determine whether skin-fold thickness is useful as an added tool in the diagnosis of Cushing's disease, we compared this value in female patients with Cushing's disease with those who presented with a similar set of symptoms. Methods: This open prospective study was conducted in an endocrinology clinic at a tertiary care center. The study population consisted of 88 females in the reproductive age group who presented to the clinic with hirsutism, oligomenorrhea, and/or obesity. Measurement of skin-fold thickness, body mass index, Ferriman-Gallwey index, and serum testosterone were performed in all patients. Results: Skin-fold thickness in the patients with Cushing's disease was 1.5±0.2 mm (range, 1.0 to 1.8 mm). This value was significantly (P<.01) lower than that in controls or subjects with other disorders that have a similar set of presenting symptoms. Conclusions: Bedside assessment of skin-fold thickness is an easy, low-cost, and noninvasive test for distinguishing Cushing's disease from disorders with similar presenting symptoms in females of reproductive age. Assessment of skin-fold thickness should be used as an adjunct to current physical and biochemical study of patients with symptoms suggestive of Cushing's disease. (Arch Intern Med. 1994;154:777-781)