Richard J. Macisaac

Richard J. Macisaac

PhD, MBBS, BSc (Hons), FRACP

Endocrinologist

over 40 years of experience

Male📍 Melbourne

About of Richard J. Macisaac

Richard J. Macisaac is an Endocrinologist based at St Vincent's Hospital Melbourne in Melbourne, VIC, Australia.


He looks after people with hormone and metabolism problems. That can include diabetes, trouble keeping blood sugar steady, and health issues that can come along with diabetes over time. At times he also supports patients with kidney-related complications, as well as conditions linked to the pituitary and other hormone glands.


Many referrals come from complex situations where things need careful checking and a steady plan. This might be after an episode of very low blood sugar, or when blood pressure and salts like potassium and sodium are not sitting at the right levels. He also works with people who have growth hormone issues, adrenal hormone problems, or other less common endocrine conditions.


With over 40 years of experience, he brings a calm, practical approach. Over the years he’s learned that good care is not just about tests. It’s also about understanding day to day life, what changes at home, and how treatment fits in. In many cases, that means explaining things clearly and updating plans as new results come in.


Richard holds a PhD and MBBS from the University of Melbourne, plus he completed specialist training through the Royal Austrasian College of Physicians, earning FRACP status. He also had a postdoctoral fellowship at St Vincent’s Institute of Medical Research in Melbourne. His education spans both clinical medicine and research training, which helps when decisions need evidence behind them.


Research is part of his background. He has worked on medical research as well as clinical care, and that can be useful when patients need a thoughtful approach to complicated endocrine and metabolic problems.


If relevant, he can also discuss options such as clinical trials. This may include studies that aim to improve care for specific endocrine or metabolic conditions, depending on what’s available and suitable.

Education

  • BSc(Hons) - Bachelor of Science (Honours); University of Melbourne; 1970
  • MBBS - Bachelor of Medicine, Bachelor of Surgery; University of Melbourne; 1975
  • PhD - Doctor of Philosophy; University of Melbourne; 1987
  • FRACP - Fellowship of the Royal Australasian College of Physicians; Royal Australasian College of Physicians; 2002
  • Postdoctoral Fellowship; St Vincent’s Institute of Medical Research, Melbourne

Services & Conditions Treated

Diabetic NephropathyType 1 Diabetes (T1D)Diabetic KetoacidosisLow Blood SugarType 2 Diabetes (T2D)Wilson DiseaseChronic Kidney DiseaseEmpty Sella SyndromeInsulinomaIslet Cell TransplantationNecrosisAbdominal Obesity Metabolic SyndromeCardiomyopathyCongenital HyperinsulinismCoronary Heart DiseaseDiabetic RetinopathyGrowth Hormone Deficiency (GHD)Heart FailureHigh Potassium LevelHyperaldosteronismHypertensionHypopituitarismLow Blood PressureLow Potassium LevelLow Sodium LevelMalnutritionMetabolic SyndromeMuscle AtrophyNeuroendocrine TumorNewborn Low Blood SugarObesityOrthostatic HypotensionOsteoporosisPancreatic CancerSensorimotor PolyneuropathySheehan SyndromeSystemic MastocytosisUrinary Tract Infection (UTI)

Publications

5 total
Comparative performance of CKD-EPI equations in people with diabetes: An international pooled analysis of individual participant data.

Diabetes research and clinical practice • February 04, 2025

Rodney Kwok, Kartik Kishore, Tina Zafari, Digsu Koye, Mariam Hachem, Ian De Boer, Tae-dong Jeong, Won-ki Min, Esteban Porrini, Petter Bjornstad, Richard Macisaac, Leonid Churilov, Elif Ekinci

Objective: This study assessed the concordance and misclassification of chronic kidney disease (CKD) stages between directly measured glomerular filtration rate (mGFR) and estimates of GFR (eGFR) using the creatinine-based CKD-EPI-2009 and the CKD-EPI-2021 equations in individuals with diabetes. Methods: Data from 5,177 individuals across six international diabetes cohorts included mGFR measurements using exogenous filtration markers. We calculated an intra-class correlation coefficient (ICC), bias, precision and accuracy between mGFR and CKD-EPI estimates using a four-level mixed-effect linear variance component model. Results: The pooled cohort included people with type 1 (n = 1,748, median age: 33 years [IQR: 27, 40], mGFR = 104.2 ml/min per 1.73 m2) and type 2 diabetes (n = 3,429, median age: 66 years [IQR: 58, 73], mGFR = 58.4 ml/min per 1.73 m2). Both CKD-EPI equations showed good agreement (2009 ICC: 0.90; 2021 ICC: 0.87) but substantial bias (2009: 3.7 ml/min/1.73 m2; 2021: 8.6 ml/min/1.73 m2), low precision (2009: 12.4 ml/min/1.73 m2; 2021: 13.91 ml/min/1.73 m2), and limited accuracy (2009 p30: 77 %; 2021 p30: 70 %) compared to mGFR. Conclusions: The use of CKD-EPI equations has the potential for misdiagnosis and suboptimal CKD management in people with diabetes. Alternative methods of estimating kidney function for people with diabetes are needed to optimally manage diabetes-related kidney disease.

Preventing Diabetic Ketoacidosis with Continuous Ketone Monitoring: Insights from a Clinical Research Case.

Diabetes Technology & Therapeutics • July 25, 2025

Yee Kong, Hanna Jones, Jennifer Ngan, Jenna Goad, Alicia Jenkins, Christopher Nolan, Dale Morrison, Elif Ekinci, Richard Macisaac, Spiros Fourlanos, Stephen Stranks, David O'neal

Delayed identification of impending diabetic ketoacidosis (DKA) often results in hospitalizations. We describe a case where continuous ketone monitor (CKM) use facilitated prompt identification and intervention for impending DKA, avoiding hospitalization. A 55-year-old male (total daily insulin dose of 0.5 units/kg/day; HbA1c 6.9% [51.9 mmol/mol]) with type 1 diabetes using automated insulin delivery (AID) wore a CKM (Abbott) and was educated in responses to ketone information as part of a clinical trial (ACTRN12624000448549). Insulin pump cannula dislodgement resulted in a rapid rise in ketone levels. Initial CKM alarm notification for elevated ketones >1.0 mmol/L prompted initiation of management, including cannula replacement and additional insulin administration. Ketosis resolved following a rise to >3.1 mmol/L without need for hospitalization. He remained asymptomatic throughout. This case highlights the potential for CKM to act as an early warning system to facilitate timely intervention for ketonemia and reduce the risk of DKA and associated hospitalizations.

Semaglutide: a key medication for managing cardiovascular-kidney-metabolic syndrome.

Future Cardiology • June 03, 2025

Richard Macisaac

Recent trials underscore the cardiovascular (CV), renal, and metabolic benefits of semaglutide in individuals with and without type 2 diabetes (T2D). In T2D, semaglutide enhances glycemic control, reduces major adverse CV events (MACE), and slows chronic kidney disease (CKD) progression. The SUSTAIN-6 trial demonstrated a 26% MACE reduction (HR 0.74; 95% CI: 0.58-0.95; p = 0.02) in high CV-risk patients with T2D using semaglutide (0.5 or 1.0 mg weekly). Similarly, the FLOW trial showed a 24% reduction in major kidney disease events (HR 0.76; 95% CI: 0.66-0.88; p = 0.002) with weekly 1.0 mg semaglutide in individuals with T2D with CKD. Beyond T2D, the SELECT trial highlighted semaglutide's efficacy in reducing MACE by 20% (HR 0.80; 95% CI: 0.72-0.90; p < 0.001) and slowing kidney function loss in overweight or obese individuals with preexisting CV disease using 2.4 mg weekly. Additionally, semaglutide alleviates heart failure symptoms and reduces hospitalizations in obese individuals regardless of T2D status. These findings underscore semaglutide's role in improving kidney, CV, and survival outcomes among high-risk patients. This review highlights the cardio-kidney-metabolic benefits of semaglutide in individuals with and without T2D to inform cardiologists about its potential to enhance patient care.

Revisiting the benefits vs risk profile of sodium-glucose co-transporter inhibitor use in type 1 diabetes. Part B: Risks of sodium-glucose co-transporter inhibitor use in type 1 diabetes and ketoacidosis risk mitigation strategies.

Diabetes Research And Clinical Practice • April 14, 2025

Jennifer Ngan, David O'neal, Melissa Lee, Yee Kong, Richard Macisaac

Sodium-glucose co-transporter (SGLT) inhibitors have been evaluated for use in people with type 1 diabetes (T1D). Despite evidence for glycaemic and non-glycaemic benefits in people with T1D as discussed in the accompanying review (Part A), the increased risk of diabetic ketoacidosis (DKA) with this class of medication remains a barrier limiting its widespread use in this population. DKA is a serious and life-threatening complication of diabetes and the excess risk associated with SGLT inhibitor use needs to be addressed before this medication could be considered as part of glycaemia and complications management in people with T1D. Understanding factors that increase DKA risk in the setting of SGLT inhibitors, as well as an appreciation of general DKA risk factors, may facilitate the development of strategies that allow for an acceptable risk versus benefit ratio to permit the use of SGLT inhibitors in people with T1D.

Comparative performance of CKD-EPI equations in people with diabetes: An international pooled analysis of individual participant data.

Diabetes Research And Clinical Practice • February 04, 2025

Rodney Kwok, Kartik Kishore, Tina Zafari, Digsu Koye, Mariam Hachem, Ian De Boer, Tae-dong Jeong, Won-ki Min, Esteban Porrini, Petter Bjornstad, Richard Macisaac, Leonid Churilov, Elif Ekinci

Objective: This study assessed the concordance and misclassification of chronic kidney disease (CKD) stages between directly measured glomerular filtration rate (mGFR) and estimates of GFR (eGFR) using the creatinine-based CKD-EPI-2009 and the CKD-EPI-2021 equations in individuals with diabetes. Methods: Data from 5,177 individuals across six international diabetes cohorts included mGFR measurements using exogenous filtration markers. We calculated an intra-class correlation coefficient (ICC), bias, precision and accuracy between mGFR and CKD-EPI estimates using a four-level mixed-effect linear variance component model. Results: The pooled cohort included people with type 1 (n = 1,748, median age: 33 years [IQR: 27, 40], mGFR = 104.2 ml/min per 1.73 m2) and type 2 diabetes (n = 3,429, median age: 66 years [IQR: 58, 73], mGFR = 58.4 ml/min per 1.73 m2). Both CKD-EPI equations showed good agreement (2009 ICC: 0.90; 2021 ICC: 0.87) but substantial bias (2009: 3.7 ml/min/1.73 m2; 2021: 8.6 ml/min/1.73 m2), low precision (2009: 12.4 ml/min/1.73 m2; 2021: 13.91 ml/min/1.73 m2), and limited accuracy (2009 p30: 77 %; 2021 p30: 70 %) compared to mGFR. Conclusions: The use of CKD-EPI equations has the potential for misdiagnosis and suboptimal CKD management in people with diabetes. Alternative methods of estimating kidney function for people with diabetes are needed to optimally manage diabetes-related kidney disease.

Clinical Trials

1 total

A Phase 2, Randomised, Placebo Controlled Study Investigating the Efficacy of Baricitinib in New Onset Type 1 Diabetes Mellitus

CompletedPhase 2Baricitinib

Type 1 diabetes (T1D) results from the killing of insulin-producing pancreatic beta cells by cells of the immune system. The study aims to slow the progressive, immune-mediated loss of insulin-producing beta cells that occurs after clinical presentation. The investigators have identified a pathway that is important for immune cells to kill beta cells, and a drug that will block this pathway and prevent beta cell death. This drug, baricitinib, is already in clinical use for rheumatoid arthritis, and is currently in clinical trials for other diseases, including childhood autoimmune diseases. It is hypothesized that baricitinib treatment for 48 weeks will preserve beta cell function in children and young adults with recently-diagnosed T1D. The trial aims to recruit 83 participants aged 10-30 years who have been recently diagnosed with T1D. Two thirds of the participants will be randomly assigned to receive baricitinib, one third will receive placebo. The trial will test if baricitinib can slow the progressive loss of insulin-producing beta cells in these patients. The primary objective is to determine if baricitinib can reduce the loss of meal-stimulated plasma C-peptide, a measure of beta-cell function. Maintaining endogenous insulin in recent-onset T1D improves glucose control and may lead to long-term improvements in glucose and lower rates of serious diabetes complications and death.

Participants: 91

Frequently Asked Questions

What conditions do you treat as an endocrinologist?
I treat a range of conditions including diabetes (Type 1 and Type 2), diabetic complications such as diabetic retinopathy and nephropathy, metabolic and hormonal disorders, thyroid issues, growth hormone problems, osteoporosis, hypertension, and other endocrine-related conditions listed in my practice.
What services do you offer for diabetes and metabolic conditions?
My services cover diabetic management and related concerns such as diabetic nephropathy, ketoacidosis, and issues with blood sugar levels. I also work with patients on obesity, metabolic syndrome, and associated hormonal and metabolic complications.
Where is your consultation location?
Consultations are at St Vincent’s Hospital Melbourne, in Melbourne, VIC.
How can I book an appointment with you?
To arrange an appointment, please contact the clinic at St Vincent’s Hospital Melbourne. They can provide available times and guidance on the referral process.
Do you manage both Type 1 and Type 2 diabetes?
Yes. I manage both Type 1 and Type 2 diabetes and related conditions, including their metabolic consequences and complications.
What other conditions or issues might you address?
Beyond diabetes, I treat a range of endocrine and metabolic disorders, such as hormonal deficiencies, cardiovascular/metabolic complications, rare conditions like insulinoma and neuroendocrine tumours, and other topics listed under my practice.

Contact Information

St Vincent's Hospital Melbourne, Melbourne, VIC, Australia

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Memberships

  • Royal Australasian College of Physicians (RACP)
  • Australian Diabetes Society (ADS)
  • American Diabetes Association (ADA)
  • Endocrine Society of Australia (ESA)