Endocrine Abstracts

Background: The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis has effects on renal growth and electrolyte regulation. However, data on adverse renal comorbidities such as renal cysts and stones in acromegaly is scarce. The current study aimed to investigate the prevalence of radiologically detectable renal comorbidities and possible related factors in the acromegaly population.

Methods: A total of 125 patients with acromegaly (46.4±11.6 years, 68 females/57 males) and 114 age-sex matched healthy subjects (45.3±12.4 years, 59 females/55 males) were included in the study retrospectively. Abdominal/urinary system ultrasonography or abdominal computed tomography results at the time of diagnosis in patients with acromegaly and at any time in healthy controls were examined. Demographic data, clinical history, and laboratory data of the patients were also recorded.

Results: Renal cyst prevalence (28.8% vs. 8.8%, P<0.001) and the longitudinal and transverse lengths of kidneys (P<0.05) were significantly higher in patients with acromegaly compared to the control group. There was no significant difference between the two groups in terms of the number of renal cysts. The presence of acromegaly disease increased the risk of renal cyst formation 12.8 fold (95% confidence interval, 2.8-58.2, P=0.01). The frequency of nephrolithiasis in acromegaly patients was similar to the control group (15.2% vs. 7.9%, P=0.08). Patients with acromegaly with renal cysts (n=36) compared to the group without cysts (n=89) were older (53.9±10.0 vs. 43.3±10.8 years, P<0.001), had a higher male sex frequency (69.4% vs. 35.9%, P=0.001), had a longer pre-diagnosis symptom duration (5 (interquartile range, 4-10) vs. 4 (2-5) years, P=0.005), and had a higher active smoking frequency (54.3% vs. 33.8%, P=0.04) and incidence of hypertension (54.3% vs. 31.8%, P=0.02) and diabetes mellitus (47.2% vs. 23.6%, P=0.01) at the time of diagnosis. Multivariate logistic regression analysis showed that age was an independent risk factor associated with the presence of renal cysts in patients with acromegaly. There was no statistically significant difference between acromegaly patients with and without cysts in terms of basal GH, nadir GH levels during oral glucose tolerance test, IGF-1xupper limit normal levels, kidney lengths, presence of kidney stones, estimated glomerular filtration rates, and serum electrolyte levels.

Conclusions: The present study showed that acromegaly disease significantly increased the prevalence of renal cysts and kidney lengths compared to the age- and sex-matched healthy population, while the prevalence of nephrolithiasis was similar. Advanced age was found to be an independent risk factor for renal cyst formation in patients with acromegaly.