Endocrine Abstracts

Background: Diabetes is an important risk factor for cardiovascular morbidity and mortality but its impact on outcome in acromegaly is unknown.

Methods: This was a nationwide, observational, matched-cohort study. Adult patients with acromegaly due to a pituitary adenoma were identified in the Swedish National Patient Registry between 1987 and 2020 and those with coexistent type 2 diabetes in the National Diabetes Registry and Drug Registry. Overall mortality, and cardiovascular mortality and morbidity were estimated in acromegalic patients with diabetes (ACRO-DM group) in comparison with those without diabetes (ACRO group) using Cox regression adjusted for multiple confounders with propensity score.

Results: The study included 786 patients with acromegaly, 254 in the ACRO-DM group and 532 in the ACRO group. Mean follow-up was 9.2 years. At baseline, mean age (SD) was 62.6 (11.4) and 60.0 (12.1) years (P=0.004) and mean duration of acromegaly was 6.8 (8.1) and 6.0 (6.2) years (P=0.098) in the ACRO-DM and ACRO group, respectively. Mean income and level of education were lower in patients with coexistent diabetes while the frequency of pre-existing cardiovascular diseases was higher (61% vs 37%, P<0.001). The use of pituitary surgery (71% vs 68%, P=0.62) and radiotherapy (16% vs 16%, P=1.00) was similar among the two groups. Overall, 466 (59%) patients received pharmacotherapy in the entire study cohort. The use of somatostatin analogues (37% vs 30%, P=0.055) and GH receptor antagonists (10% vs 6%, P=0.063) was somewhat more frequent in the ACRO-DM group. The unadjusted overall mortality rate per 1000 person-years was 35.1 (95% CI 27.2–44.7) for the ACRO-DM group and 20.1 (16.5–24.3) for the ACRO group, with a hazard ratio (HR) of 1.58 (1.12–2.23) after adjustment for multiple confounders. The ACRO-DM group had increased cardiovascular mortality (HR 2.11, 1.09–4.10) and increased risk of cardiovascular diseases (HR 1.49, 1.21–1.82). Risk factor for cardiovascular diseases were age [HR 1.03 (95% CI 1.02–1.04)], diabetes duration [HR 1.09 (1.05–1.13)], diastolic blood pressure [HR 1.02 (1.00–1.04)], body mass index [HR 1.05 (1.01–1.09)], and treatment with antihypertensive drugs [HR 2.1 (1.21–3.64)] or lipid-lowering medication [HR 1.60 (1.08–2.36)].

Conclusions: Diabetes in patients with acromegaly was associated with excess overall and cardiovascular mortality and increased risk of cardiovascular diseases. These findings are novel and emphasize the need of optimizing management of acromegaly to prevent the development of diabetes since it might improve survival.