Progression of acromegalic arthropathy despite long-term biochemical control: a prospective, radiological study

Objective: Arthropathy is an invalidating complication of acromegaly, of which the prognosis and determinants are currently unknown in treated acromegaly. Therefore, the objective of the present study was to investigate the radiographic progression of arthropathy over a mean follow-up period of 2.6 years and determinants of outcome in patients with long-term, well-controlled acromegaly. Design: Prospective follow-up study. Methods: In a prospective cohort study we studied 58 patients (mean age 62, women 41%) with controlled acromegaly for a mean of 17.6 years. Radiographic progression of joint disease was defined by the Osteoarthritis Research Society International classification as a 1-point increase in joint space narrowing (JSN) or osteophyte scores on radiographs of the hands, knees, and hips obtained at the first study visit and after 2.6 years. Potential risk factors for progression were assessed. Results: Progression of osteophytes and JSN was observed in 72 and 74% of patients respectively. Higher age predisposed for osteophyte progression. Patients with biochemical control by somatostatin (SMS) analogs had more progression of osteophytosis than surgically cured patients (odds ratio=18.9, P=0.025), independent of age, sex, BMI, baseline IGF1 SDS and exon 3 deletion of the GHR. This was also evident for JSN progression, as were higher age and higher baseline IGF1 SDS. Conclusions: Acromegalic patients have progressive JSN and osteophytosis, despite long-term biochemical control. Parameters reflecting GH/IGF1 activity were associated with progressive joint disease. Remarkably, biochemical control by SMS analogs was associated with more progression than surgical cure. Although the present study is not a randomized controlled trial, this may indicate insufficient GH control according to current criteria and the need for more aggressive therapy.