Prof.MichioOtsuki - AOCE 2026

Education: 2000: Ph.D., Osaka University Graduate School of Medicine 1992: M.D., Yamagata University Medical School Academic and Clinical Positions 2021-present: Professor and Chair in Department of Endocrinology, Tokyo Women’s Medical University, School of Medicine, Graduate School of Medicine 　2020-2021: Associate Professor in Department of Metabolic Medicine, Osaka University Graduate School of Medicine 　2009-2020: lecturer in Department of Metabolic Medicine, Osaka University Graduate School of Medicine 　2007-2009: Assistant Professor in Department of Metabolic Medicine, Osaka University Graduate School of Medicine 　2004-2007: Resident in Osaka University Hospital 　2002-2003: Researcher in Department of Biosciences at Novum, Karolinska Institutet 　2000-2002: Guest Researcher in Department of Biosciences at Novum, Karolinska Institutet　　　1998-2000: Resident in Department of Molecular Medicine, Osaka University Graduate School of Medicine 　1995-1998: Research Fellow in Department of Molecular Medicine, Osaka University Medical School 　1993-1995: Clinical Fellow in Internal Medicine II, Osaka Teishin Hospital 　1992-1993: Junior Resident in Department of Medicine III, Osaka University Medical School

22 MARCH

Time	Session

14:00 15:30	[Symposium] Pituitary (3) Acromegaly Acromegaly and Cardiovascular Disease: The Research in Taipei Veterans General Hospital Harn-Shen ChenTaiwan Speaker Acromegaly and Cardiovascular Disease: The Research in Taipei Veterans General HospitalAcromegaly, characterized by chronic excess growth hormone (GH) and elevated insulin-like growth factor-1 (IGF-1), is associated with increased morbidity and premature mortality, particularly from cardiovascular (CV) complications. Research from Taipei Veterans General Hospital (Taipei VGH) over the past decade has systematically examined how biochemical control, metabolic status, and cardiac function influence patient outcomes, forming a comprehensive institutional understanding of acromegaly-related CV risk. Early studies established the prognostic importance of postoperative hormonal normalization following trans-sphenoidal adenomectomy (TSA). Patients achieving stringent biochemical remission demonstrated markedly reduced long-term mortality, whereas persistent GH/IGF-1 elevation remained a strong predictor of premature death. Even partial hormonal improvement provided measurable survival benefit, highlighting the need for aggressive management and close monitoring after surgery. Subsequent work addressed the metabolic impact of medical therapy, particularly long-acting octreotide. While effective in reducing GH/IGF-1 levels, somatostatin analogs impaired insulin secretion and frequently worsened glucose tolerance. These findings underscore the need to balance biochemical control with careful metabolic surveillance, especially in patients with preexisting glucose abnormalities. In 2020, a nationwide epidemiological study expanded the perspective by detailing incidence, comorbidities, re-operation rates, cancer risk, and mortality trends across Taiwan. Despite modern advances, patients with acromegaly continued to exhibit elevated mortality—predominantly from CV and malignant causes—reinforcing the significance of early diagnosis and rigorous long-term management. Complementing epidemiologic insights, a focused clinical study demonstrated that successful surgical remission led to significant improvements in traditional CV risk factors, including reductions in HbA1c, LDL cholesterol, total cholesterol, and blood pressure one year after TSA. These benefits were most pronounced in patients with normalized IGF-1. The most recent study linked degrees of biochemical control to cardiac structure and function. Patients with uncontrolled or partially controlled acromegaly exhibited increased left ventricular mass and impaired diastolic function, indicating early acromegalic cardiomyopathy even when systolic function remained preserved. Collectively, the Taipei VGH research program highlights that full biochemical remission is essential not only for reducing mortality but also for reversing metabolic abnormalities and preventing progressive cardiac dysfunction. Medication Management for Acromegaly Cheol Ryong KuSouth Korea Speaker Medication Management for Acromegaly Acromegaly: GH Response Pattern to Oral Glucose Load and Personalized Medicine Michio OtsukiJapan Speaker Acromegaly: GH Response Pattern to Oral Glucose Load and Personalized MedicineAcromegaly is characterized by elevated levels of growth hormone (GH) and insulin-like growth factor-1 (IGF-1), with resultant signs and symptoms of hypersomatotropism. To examine autonomous secretion of GH, an oral glucose tolerance test (OGTT) is used. In most healthy individuals, GH levels decrease to a nadir below 0.4 mg/L after OGTT. In contrast, patients with acromegaly fail to suppress serum GH levels after OGTT. Interestingly, a paradoxical GH response to oral glucose (OG) load is found in one third of acromegalic patients. The mechanism of this paradoxical response in acromegaly is mediated by glucose-dependent insulinotropic polypeptide, which is released after OG administration We found that the paradoxical GH response to OG load reflected the clinical characteristics. The patients the paradoxical GH response to OG load (OG responders) had substantially greater IGF-1 SD scores than nonresponders. Regarding glucose metabolism, 120-minute plasma glucose and immunoreactive insulin after OG administration and hemoglobin A1c were significantly greater in OG responders than in nonresponders. GH levels during octreotide or bromocriptine testing were decreased more significantly in OG responders than in nonresponder. The proportion of pituitary tumors with hypointensity on T2-weighted MRI was significantly greater in OG responders than in nonresponders. OGTT is essential to evaluate autonomous secretion of GH. The paradoxical GH response to OG load is the useful for evaluation of the clinical characteristics of acromegaly and leads to the personalized medicine of acromegaly. 201DE

Time

Session

14:00

15:30

[Symposium] Pituitary (3)

Acromegaly

Acromegaly and Cardiovascular Disease: The Research in Taipei Veterans General Hospital

Harn-Shen ChenTaiwan Speaker Acromegaly and Cardiovascular Disease: The Research in Taipei Veterans General HospitalAcromegaly, characterized by chronic excess growth hormone (GH) and elevated insulin-like growth factor-1 (IGF-1), is associated with increased morbidity and premature mortality, particularly from cardiovascular (CV) complications. Research from Taipei Veterans General Hospital (Taipei VGH) over the past decade has systematically examined how biochemical control, metabolic status, and cardiac function influence patient outcomes, forming a comprehensive institutional understanding of acromegaly-related CV risk. Early studies established the prognostic importance of postoperative hormonal normalization following trans-sphenoidal adenomectomy (TSA). Patients achieving stringent biochemical remission demonstrated markedly reduced long-term mortality, whereas persistent GH/IGF-1 elevation remained a strong predictor of premature death. Even partial hormonal improvement provided measurable survival benefit, highlighting the need for aggressive management and close monitoring after surgery. Subsequent work addressed the metabolic impact of medical therapy, particularly long-acting octreotide. While effective in reducing GH/IGF-1 levels, somatostatin analogs impaired insulin secretion and frequently worsened glucose tolerance. These findings underscore the need to balance biochemical control with careful metabolic surveillance, especially in patients with preexisting glucose abnormalities. In 2020, a nationwide epidemiological study expanded the perspective by detailing incidence, comorbidities, re-operation rates, cancer risk, and mortality trends across Taiwan. Despite modern advances, patients with acromegaly continued to exhibit elevated mortality—predominantly from CV and malignant causes—reinforcing the significance of early diagnosis and rigorous long-term management. Complementing epidemiologic insights, a focused clinical study demonstrated that successful surgical remission led to significant improvements in traditional CV risk factors, including reductions in HbA1c, LDL cholesterol, total cholesterol, and blood pressure one year after TSA. These benefits were most pronounced in patients with normalized IGF-1. The most recent study linked degrees of biochemical control to cardiac structure and function. Patients with uncontrolled or partially controlled acromegaly exhibited increased left ventricular mass and impaired diastolic function, indicating early acromegalic cardiomyopathy even when systolic function remained preserved. Collectively, the Taipei VGH research program highlights that full biochemical remission is essential not only for reducing mortality but also for reversing metabolic abnormalities and preventing progressive cardiac dysfunction.
Medication Management for Acromegaly

Cheol Ryong KuSouth Korea Speaker Medication Management for Acromegaly
Acromegaly: GH Response Pattern to Oral Glucose Load and Personalized Medicine

Michio OtsukiJapan Speaker Acromegaly: GH Response Pattern to Oral Glucose Load and Personalized MedicineAcromegaly is characterized by elevated levels of growth hormone (GH) and insulin-like growth factor-1 (IGF-1), with resultant signs and symptoms of hypersomatotropism. To examine autonomous secretion of GH, an oral glucose tolerance test (OGTT) is used. In most healthy individuals, GH levels decrease to a nadir below 0.4 mg/L after OGTT. In contrast, patients with acromegaly fail to suppress serum GH levels after OGTT. Interestingly, a paradoxical GH response to oral glucose (OG) load is found in one third of acromegalic patients. The mechanism of this paradoxical response in acromegaly is mediated by glucose-dependent insulinotropic polypeptide, which is released after OG administration We found that the paradoxical GH response to OG load reflected the clinical characteristics. The patients the paradoxical GH response to OG load (OG responders) had substantially greater IGF-1 SD scores than nonresponders. Regarding glucose metabolism, 120-minute plasma glucose and immunoreactive insulin after OG administration and hemoglobin A1c were significantly greater in OG responders than in nonresponders. GH levels during octreotide or bromocriptine testing were decreased more significantly in OG responders than in nonresponder. The proportion of pituitary tumors with hypointensity on T2-weighted MRI was significantly greater in OG responders than in nonresponders. OGTT is essential to evaluate autonomous secretion of GH. The paradoxical GH response to OG load is the useful for evaluation of the clinical characteristics of acromegaly and leads to the personalized medicine of acromegaly.

201DE

Prof.MichioOtsuki Japan

22 MARCH