Clinical predictors of GH deficiency in surgically cured acromegalic patients

Even in patients with cured acromegaly, GH deficiency (GHD) after transsphenoidal adenomectomy (TSA) adversely affects body composition and inflammatory biomarkers of cardiovascular risk. In this study, clinical parameters for predicting GHD after TSA in 123 cured acromegalic patients were investigated.

GH levels were measured at 6, 12, 18, 24, 48, and 72 h after TSA and serial insulin tolerance tests were conducted at 6 months, 2 years, and then every 2 years after TSA.

GHD was found in 12 patients (9.8%) at 4.1 (range: 0.5-4.1) years after TSA. IGF1 levels were significantly lower at 6 months after TSA in GHD group than intact GH group (175.9 vs 316.8 μg/l, range: 32.0-425.0 and 96.9-547.3 respectively, P=0.008). Adenomas involving both sides of the pituitary gland were significantly more frequent in GHD patients (29.7 vs 83.3%; P=0.002). Furthermore, immediate postoperative 72-h GH levels after TSA were significantly lower (0.17 vs 0.45, range: 0.02-0.93 and 0.02-5.95 respectively, P=0.019) in GHD patients. In multiple logistic regression analysis, bilaterality of tumor involvement (odds ratio (OR)=10.678, P=0.003; 95% CI=2.248-50.728) and immediate postoperative 72-h GH level (OR=0.079, P=0.047; 95% CI=0.006-0.967) showed significant power for predicting GHD.

These data suggest that bilateral involvement of a pituitary adenoma and severely decreased immediate postoperative serum GH levels at 72 h after TSA may be independent risks factor for accelerated GHD in acromegalic patients.