Senior Medical Leadership Team

Dr. Susan Brien is Senior Vice President Medical, Academic and Research Affairs for Horizon Health Network. Originally from New Brunswick and prior to joining Horizon, Dr. Brien served as the Director, Practice and System Innovation at the Royal College of Physicians and Surgeons of Canada. She played an integral part in the Royal College’s international initiative as the Vice-President Asia Pacific. Her portfolio included overseeing new regional, national and international projects, facilitating professional development activities such as team training, simulation, performance assessment, simulation accreditation, and curriculum integration. Dr. Brien also held leadership roles including Chief of Neurosurgery at Le Centre de santé et de services sociaux de Gatineau, where she had practiced as a neurosurgeon. She served as the inaugural Director of Operations for Quebec, Eastern Canada and Nunavut with the Canadian Patient Safety Institute, where she was responsible for national patient safety education. Dr. Brien is an Adjunct Professor of Surgery at the University of Ottawa and a faculty lecturer with the Division of Neurology and Neurosurgery at McGill University, where she also served as the UGME Accreditation Lead for the Gatineau Campus. She is a certified physician executive and member of the American Association of Physician Leaders. As Vice President Medical, Academic and Research Affairs. Dr. Brien oversees Horizon’s Chief Medical Information Officer, Physician Wellness, Medical Program Management and ensures systems, policies and procedures support excellence in medical care and champions constant improvement, innovation, and research.

Dr. Jody Enright served as Medical Director for Moncton and the surrounding area before assuming the role of Senior Medical Executive Director in 2025. Dr. Enright has been a family physician in the Department of Family Medicine at Horizon’s The Moncton Hospital since 2009 and is a strong advocate for patients and their families, and understands the challenges faced by our patients, clinicians, and health care professionals. As a Program Management leader, Dr. Enright builds strong, professional relationships with physicians, the leadership team, stakeholders, staff, and communities while ensuring the development of a regional medical affairs strategy in accordance with Horizon’s mission and vision. Born in Moncton, Dr. Enright received all of her university training in Atlantic Canada and has also served as an Assistant Professor with her alma mater, Dalhousie University Faculty of Medicine, since 2011. Before entering the field of medicine, Dr. Enright worked in both the human resources and public relations sectors.

Dr. Ashley (Ash) McLellan served as Medical Director for the Fredericton and Upper River Valley area before assuming the role of Senior Medical Executive Director in 2025. Dr. McLellan previously held the roles of Urology Division Head and Local Chief of Surgical Program at the Dr. Everett Chalmers Regional Hospital (DECRH), is an assistant professor at Dalhousie University. As a Program Management leader, Dr. McLellan builds strong, professional relationships with physicians, the leadership team, stakeholders, staff, and communities while ensuring the development of a regional medical affairs strategy in accordance with Horizon’s mission and vision. Dr. McLellan graduated from Dalhousie Medical School in 2000 and completed is residency training in 2005. He has worked as a urologist at the DECRH since completing his medical degree. Roads University.

William A. Cook graduated from Queen’s University Medical School and Dalhousie University, and is a Fellow of the Royal College of Surgeons of Canada (Plastic Surgery). Dr. Cook practiced plastic surgery in Fredericton for 25 years, and from 2005–09 was Vice President Medicine at River Valley Health, formerly the Fredericton and Upper River Valley area of Horizon Health Network (Horizon). He continues to be active in Horizon’s Ethics Services. After earning his PhD in Bioethics, Dr. Cook lead the development of a bioethics service in the Fredericton area, where he practices. He has been integrally involved in Horizon’s Ethics Services Department and Research Ethics Board since Horizon was formed. His current medical practice is focused on MindBody-Lifestyle Medicine and Mindfulness, helping people to extend their self-understanding and build resilience through consultation, counselling, a monthly Introduction to MindBody Medicine Program, and a more intensive eight-week Mindfulness and Conscious Living Program. Dr. Cook has studied and practiced yoga for 26 years, and holds numerous certifications in mindfulness and yoga, yoga therapy, and trauma sensitive yoga training. Dr. Cook is a recipient of the Rotary International Paul Harris Award for Humanitarian Service. As for his personal interests and hobbies, in addition to practicing yoga and meditation, Dr. Cook is a naturalist at heart and enjoys time outdoors with family and friends, gardening, hiking, snowshoeing, canoeing and just connecting with nature.

A trained family medicine physician, Dr. Eugene Mah received his Bachelor of Science and his medical degree from the University of British Columbia. He went on to complete his family medicine residency at Dalhousie University, where he met his wife while on rotation in Fredericton. After finishing his residency, Dr. Mah and his wife worked and travelled in and outside of Canada before settling down in his wife’s hometown of Miramichi in 2002 to raise their children. Since then, Dr. Mah has proudly worked in the emergency department of Horizon’s Miramichi Regional Hospital, serving the Miramichi and surrounding area..

Dr. Nachiketa (Nachi) Sinha has been practicing as a consultant psychiatrist in New Brunswick since 2006. Prior to that he graduated from Karnatak University in Dharwad, India in 2001, received his training in psychiatry at Cambridge Deanery, and worked at the Bedfordshire and Luton NHS Trust in the United Kingdom. He is an assistant professor with the Faculty of Medicine at Dalhousie University in Halifax, N.S., has an executive MBA in health care from the University of British Columbia’s Sauder School of Business, and is the author of an internationally recognized self-help book, Empowered and Strong. Dr. Sinha moved to the Moncton area in February 2016 and has been providing clinical services through his clinic on Mountain Road. Prior to this, he served the communities of Woodstock and Perth-Andover in the picturesque Upper River Valley. Some of his interests centre around providing equity in treatment and he is recognized nationally for his role in providing culturally appropriate psychiatric care to the First Nations communities of New Brunswick. Dr. Sinha has been active in initiating important changes to mental health delivery in New Brunswick and has a unique ability to bring different stakeholders together for a common goal. He played an instrumental role in the introduction of Community Treatment Orders (CTOs) in New Brunswick. Dr. Sinha is the current president of Horizon Health Network’s Medical Staff Organization, Medical Director of Addiction and Mental Health in the Moncton area, and treasurer and Executive Board Director of the New Brunswick Medical Society. He is also involved in multiple organizations provincially and nationally, including the role of president of the New Brunswick Psychiatric Association (NBPA) of which he was elected twice by his colleagues to the position of in 2015-16, and again in 2016-17. He also is a member of the Canadian Psychiatric Association (CPA) Board of Directors. Dr. Sinha has held several other prestigious positions such as former president of the Canadian Psychiatric Association in addition to being a former Board member of the CPA’s Board of Directors and Foundation and Chair of the CPA’s Council of Provinces. Dr. Sinha also served as the past treasurer of the New Brunswick Medical Society and, prior to being NBPA president, he was the association’s treasurer and played a crucial role in revitalizing the association and making psychiatry a relevant voice in the province. Dr. Sinha is a past, and only, psychiatrist member of Accreditation Canada’s Physician Advisory Committee, and was also involved in the Mental Health and Addictions Leadership Forum of the Government of New Brunswick. In 2018, Dr. Sinha was recognized by the Provincial Government of New Brunswick for his contributions to mental health care in the province and was inducted as Fellow of the Canadian Psychiatric Association in 2019, an honour which has only been bestowed on approximately 140 psychiatrists since the Association’s establishment in 1951. Dr. Sinha is of East Indian origin and is proud of his cultural heritage grounded in the principles of compassion, non-violence and equality. His ability to work and integrate with different cultures has allowed him to collaborate in varied settings over three continents. He is a team player and strongly believes in patient- and client-centred care. Dr. Sinha is a proud father to his beloved son and enjoys photography and writing in his spare time.

Dr. Martha Mills received her medical degree and residency training in Obstetrics and Gynecology from Dalhousie University before establishing her Fredericton practice in 2001. A champion of excellence in obstetric and gynecologic care, Dr. Mills is a Fellow of the Royal College of Physicians and Surgeons of Canada (Obstetrics and Gynecology), and a member of the Society of Obstetrics and Gynecology (SOGC) of Canada, American Association of Gynecologic Laparoscopists, and Atlantic Society of Obstetricians and Gynecologists (ASOG). Dr. Mills has held multiple local, provincial and national committee and leadership positions including President of the Specialty Council of the New Brunswick Medical Society, President and Scientific Director of the ASOG, Chair of the Drugs and Therapeutics Committee and Medication Management Committee and member of the Brand Recognition Program for SOGC. From 2005 to 2014, Dr. Mills served as the Department of Obstetrics and Gynecology’s clinical department head for the Fredericton area. An educator and mentor, Dr. Mills received the Carl Nimrod Educator Award in 2016 from the Association of Professors of Obstetrics and Gynecology (SOGC). In addition to her teaching duties with Dalhousie University and Memorial University, she has served as a member of both undergraduate and postgraduate medical education committees, and the Dalhousie Medical School Admissions Committee. In her spare time, Martha can be found on the golf course or spending time with her family, especially her two grandchildren.

Dr. Mike Forsythe has been an orthopedic surgeon at Horizon’s The Moncton Hospital since 2005, specializing in sports medicine and arthroplasty. He holds consulting and surgical privileges at Horizon’s Sackville Memorial Hospital, and he also serves as a Clinical Associate Professor of Medicine at both Dalhousie University and Memorial University. Dr. Forsythe earned his Bachelor of Science in Biology with distinction from Bishop’s University, followed by a medical degree from Dalhousie University, where he also graduated with distinction in 1998. He completed his orthopedic surgery residency at Dalhousie and pursued fellowships in arthroplasty at Prince Charles Hospital in Brisbane, Australia, and sports medicine at McGill University. In 2003, he became a Fellow of the Royal College of Physicians and Surgeons of Canada. Throughout his career, Dr. Forsythe has received numerous accolades, including the Bubsy Grant Award for Team Physician with Mount Allison Athletics, most recently in 2023. In addition to his clinical practice, Dr. Forsythe has contributed extensively to research in orthopedics, rehabilitation, trauma, and patient communication. Beyond his professional commitments, Dr. Forsythe is an active community volunteer, serving as the medical team physician for the Moncton Wildcats Major Junior Hockey team and Mount Allison Varsity Sports. An avid athlete, he enjoys playing hockey and golf in his free time.

Dr. Sanjay Siddhartha received his medical degree from Medical College Raipur and is a Fellow of the Royal College of Physicians of Canada in Psychiatry (FRCPC). Dr. Siddhartha is a champion of community-based mental health care and caring for patients in their own environment. He is one of the few physicians in the province to still make house calls, which is an essential part of his frontline mental health support work. He is also a member of the Flexible Assertive Community Treatment (F.A.C.T.) team and the Mobile Crisis Unit team. Dr. Siddhartha continuously strives to improve access to mental health services and has been instrumental in reducing wait times to see a psychiatrist to well below the provincial and national average. Because of his commitment to frontline care, he was instrumental in creating a unique and highly successful program in which patients referred to the Horizon’s Addition and Mental Health Services in the Miramichi area undergo a psychiatric screening to rule out serious mental illness. He is a firm believer in multidisciplinary teams and his passion for practicing and providing frontline care sets an example for his colleagues. In 2019, Dr. Siddhartha was awarded the Canadian Certified Physician Executive (CCPE) designation by the Canadian Society of Physician Leadership to recognize his exemplary performance as a leader. He is only one of three New Brunswick physicians to receive this distinction. Dr. Siddhartha has presented at the World Psychiatric Association Conferences in Beijing in 2010, Barcelona in 2015, and Mexico City in 2018. He has also presented at The Royal Australian and New Zealand Psychiatric Association conferences in 2014, 2016, 2018, and 2019. He also serves as Chair of the New Brunswick Psychiatric Association Board of Directors, of which he also served as the former president.