Long-term clinical control in acromegaly patients with postoperative discordant nadir growth hormone during oral glucose tolerance test and insulin-like growth factor 1 levels: a retrospective observational study and literature review.
Ishida. Tomohisa T; Kawaguchi. Tomohiro T; Ogawa. Yoshikazu Y; Endo. Hidenori H
Key Findings
- Some patients had normal GH suppression but high IGF‑1 after surgery, which later normalized on its own over 3‑5 years.
- Other patients had abnormal GH suppression but normal IGF‑1, and they stayed stable for up to 11 years.
- Overall, most patients remained disease‑controlled without additional therapy, suggesting careful monitoring may be enough.
Practical Outcomes
- For biohackers, this research doesn’t change how you’d use IGF‑1 supplements, but it highlights that mismatched lab results don’t always mean you need more intervention. If you’re monitoring your own hormone levels, consider the whole clinical picture and avoid over‑treating based on a single test.
Summary
The study looked at people who had surgery for a hormone‑overproduction tumor (acromegaly) and found that even when lab tests for growth hormone and IGF‑1 didn’t match, most patients stayed stable without extra treatment for many years.
Abstract
Postoperative evaluation in patients with acromegaly typically involves measuring insulin-like growth factor 1 (IGF-1) levels and assessing growth hormone (GH) suppression via an oral glucose tolerance test (OGTT). However, discrepancies between these results are not uncommon. Despite this, there are very few studies examining long-term clinical outcomes in patients with persistent discordance between GH nadir and IGF-1 levels. In this study, we focused on such patients and conducted a retrospective analysis to clarify their mid- to long-term outcomes, alongside a review of relevant literature. We retrospectively reviewed patients with acromegaly who underwent transsphenoidal resection of pituitary tumors at a single institution and had serial endocrinological evaluations for more than one year between May 2005 and July 2020. Patients were divided into two groups: those with normal GH suppression during OGTT but elevated IGF-1 levels (Group I) and those with abnormal GH suppression but normal IGF-1 levels (Group II) at their 1-year postoperative evaluation. We investigated whether IGF-1 levels normalized or re-elevated over time, alongside monitoring clinical signs and comorbidity management. During the study period, 52 patients who were evaluated by serial IGF-1 and OGTT, 10 demonstrated discordance between GH nadir and IGF-1 levels-3 in Group I and 7 in Group II. In all Group I patients, delayed normalization of IGF-1 was observed, taking 3 to 5 years. No IGF-1 re-elevations occurred, and clinical signs and comorbidities were well controlled. In Group II, abnormal GH suppression during OGTT persisted in all patients; however, IGF-1 levels remained within the normal range without re-elevations. Clinical signs and comorbidities remained clinically stable without the need for additional therapy during the 11-year follow-up period. Most patients achieved a mid- to long-term disease-controlled state without additional treatment. Given the potential risk of GH deficiency from further treatment, it may be reasonable to consider patients clinically controlled as long as IGF-1 levels remain normalized, with careful long-term monitoring recommended.
Study Information
pubmed
2025
2025-12-10T00:00:00.000Z
10.1007/s00423-025-03951-x