Determinants of clinical outcome and survival in acromegaly

Abstract

Objective: The extent to which treatment modifies the excess in morbidity and mortality in acromegaly remains uncertain. This study investigates the determinants of final outcome following therapy for acromegaly.

Design: A retrospective analysis of patients treated at the Departments of Endocrinology and Neurosurgery, Auckland Hospital, New Zealand.

Patients: One hundred and fifty-one patients (63 females and 88 males) with acromegaly or gigantism treated between the years 1964 and 1989. The mean duration of follow-up was 12 years (median 11 years).

Measurements: Patients had their age, estimated duration of symptoms preceding diagnosis, serum GH at diagnosis, presence of diabetes mellitus, cardiovascular disease, hypertension and/or osteoarthritis at diagnosis and the last known serum GH documented. The final outcome at the time of study was graded under three classes: dead (n = 32), those with major complications (n = 47) and those with minor/no complications (n = 67).

Results: The mean age at diagnosis of acromegaly was 41 years and the average estimated duration of symptoms prior to diagnosis was 7 years, with older patients showing longer duration of symptoms preceding diagnosis (P = 0.0002). Final outcome (dead, alive with major complications, alive and well) was significantly worse in those with older age at diagnosis (P = 0.008), longer duration of symptoms before diagnosis (P = 0.03) and higher GH at last follow-up (P = 0.0001). In multivariate analysis, survival was significantly influenced by the last known GH (P = 0.0001), presence of hypertension (P = 0.02) or cardiac disease (P = 0.03) at diagnosis, and duration of symptoms prior to diagnosis (P = 0.04). Survival in the acromegalic group, irrespective of treatment, was reduced by an average of 10 years compared with the non-acromegalic population.

Conclusions: Acromegaly has a significant adverse effect on well-being and survival. The predominant determinant of outcome is the final serum GH level following treatment.