High prevalence of biochemical acromegaly in primary care patients with elevated IGF-1 levels.

OBJECTIVE The estimated prevalence of acromegaly is 40-125 per million. The diagnosis of acromegaly is often delayed due to deficits in recognizing the signs of the disease. It is not known how many subjects with increased IGF-1 levels have acromegaly. We aimed to assess the prevalence of acromegaly in primary care by screening for elevated IGF-1 levels. DESIGN A cross-sectional, epidemiological study (the DETECT study). Patients A total of 6773 unselected adult primary care patients were included. MEASUREMENTS We measured IGF-1 in all patients and recommended further endocrine evaluation in all patients with elevated IGF-1 levels (> 2 age-dependent SDS). RESULTS Of 125 patients with elevated IGF-1 levels, 76 patients had indeterminate results and acromegaly could be excluded in 42 patients. One patient had known florid acromegaly. Two patients had newly diagnosed acromegaly and pituitary adenomas. Four patients had biochemical acromegaly but refused further diagnostics. This corresponds to a prevalence of 1034 per million patients. CONCLUSIONS Our study shows a high prevalence of undiagnosed acromegaly in primary care. These results imply that acromegaly is underdiagnosed and stress the importance of detecting acromegaly.