Jennifer Mammen, M.D., Ph.D., M.Phil.

Jennifer Sophie Mammen, M.D., Ph.D., M.Phil.

Headshot of Jennifer Mammen
  • Assistant Professor of Medicine

Languages: English, French


Endocrinology, Thyroid, Adrenal and Pituitary Disorders in Autoimmunity and Aging more

Research Interests

Thyroid, adrenal and pituitary function in aging

Request an Appointment

Insurance Information

Main Phone

Outside of Maryland & Washington D.C.

Request Appointment

International Patients

Request Appointment


Johns Hopkins Bayview Medical Center

Appointment Phone: 410-955-3663
4940 Eastern Avenue
BMO Building
Baltimore, MD 21224 map
Fax: 410-367-2042


Jennifer Mammen, M.D., Ph.D., Assistant Professor of Medicine, is a member the Division of Endocrinology, Diabetes and Metabolism.

Dr. Mammen practices general endocrinology with a focus on thyroid, adrenal and pituitary disorders. She is actively engaged in research on hormonal function and aging. more


  • Assistant Professor of Medicine

Departments / Divisions



  • MD; Johns Hopkins University School of Medicine (2004)


  • Medicine; Johns Hopkins University School of Medicine (2006)


  • Endocrinology; Johns Hopkins University School of Medicine (2010)

Board Certifications

  • American Board of Internal Medicine (Endocrinology/Diabetes/Metabolism) (2010)

Additional Training

  • M.Phil., University of Cambridge (United Kingdom) (1992)
  • PhD, Johns Hopkins Bloomberg School of Public Health (2004)

Research & Publications

Research Summary

An appreciation for the complexity of human responses to aging has allowed us to recognize that there are multiple pathophysiology processes behind seemingly similar clinical changes in serum hormone levels among older adults.  Using data from the Baltimore Longitudinal Study of Aging, we have recently reported the novel observation that most healthy older adults have relatively stable thyroid function, despite higher average levels among older compared to younger groups. We have demonstrated the presence of diverse aging patterns in the thyroid axis amongst older adults. In particular, while some people clearly have developing hypothyroidism from primary thyroid failure, others have changes in their pituitary that give rise to a similar TSH elevation without lowering thyroid hormone levels.  These different patterns imply different treatment approaches are appropriate in individuals. Ongoing research is directed towards being able to distinguish these differences without the long-term follow up data that is available in the BLSA, in order to develop clinically relevant tests and improve care. We have identified practice patterns and risk factors for thyroid hormone over-use and misuse that constitute a significant public health problem in older adults, and particularly women, which drives the need for targeted therapy and personalized medicine to come to endocrinology.

Selected Publications

Mammen JS, McGready J, Oxman R, Chia CW, Ladenson PW, Simonsick EM. Thyroid hormone therapy and risk of thyrotoxicosis in community-resident older adults: Findings from the Baltimore Longitudinal Study of Aging. Thyroid. 2015; 25(9):979 [PMID: 26177259]

Mammen JS, McGready J, Ladenson PW, Simonsick EM. Unstable thyroid function in older adults is caused by alternations in both thyroid and pituitary physiology and associated with increased mortality.  Thyroid 2017; 27(11)1370 [PMID 28854871]

Simonsick EM, Chia CW, Mammen JS, Egan JM, Ferrucci L. Free Thyroxine and Functional Mobility, Fitness, and Fatigue in Euthyroid Older Men and Women in the Baltimore Longitudinal Study of Aging. J Gerontol A Biol Sci Med Sci. 2016; 71(7):961 [PMID: 26791089]

Brahmer JR, Lacchetti C, Schneider BJ, Atkins MB, Brassil KJ, Caterino JM, Chau I, Ernstoff MS, Gardner JM, Ginex P, Hallmeyer S, Holter Chakrabarty J, Leighl NB, Mammen JS, McDermott DF, Naing A, Nastoupil LJ, Phillips T, Porter LD, Puzanov I, Reichner CA, Santomasso BD, Seigel C, Spira A, Suarez-Almazor ME, Wang Y, Weber JS, Wolchok JD, Thompson JA. Managements of Immune-Related Adverse Events in Pathients Treated With Immune Checkpoint Inhibitor Therapy: American Society of Clinical Oncology Clinical Practice Guideline Jclin Oncol 2018 Feb 14 [Epub ahead of print] [PMID: 29442540]. 

Mammen, JS and Cooper D, “Lobectomy vs total thyroidectomy in suspicious or malignant lesions” in Transoral Endocrine and Neck Surgery, edited by Russell JO, Tufano R, and Inabnet WB ed. In press.  Springer.

Activities & Honors


  • Alpha Omega Alpha, 2004
  • Turock Clinical Scholar, Turock Family Foundation, 2016
  • Passano Physician Scientist, Passano Foundation, 2013 - 2015
  • Churchill Scholar, Churchill Foundation, 1991 - 1992
  • Medical Scientist Training Program, National Institutes of Health, 1995 - 2004


  • American Thyroid Association
  • Endocrine Society

Patient Ratings & Comments

The Patient Rating score is an average of all responses to physician related questions on the national CG-CAHPS Medical Practice patient experience survey through Press Ganey. Responses are measured on a scale of 1 to 5, with 5 being the best score. Comments are also gathered from our CG-CAHPS Medical Practice Survey through Press Ganey and displayed in their entirety. Patients are de-identified for confidentiality and patient privacy.

Is this you? Edit Profile
back to top button