Marianne Monahan, MD

Medicare activity in 2024

Official CMS public-use data for Marianne Monahan, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Most frequent services

1. Injection, epoetin alfa, (for non-esrd use), 1000 units (J0885)1,340 services
2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)490 services
3. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)424 services
4. Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)408 services
5. Dialysis services, 4 or more physician visits per month (20 years or older) (90960)270 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

• High blood pressure75%
• High cholesterol75%
• Chronic kidney disease75%
• Diabetes56%
• Ischemic heart disease48%
• Arthritis47%

Hospitals where Marianne Monahan works

Medicare's Facility Affiliation Data lists Marianne Monahan at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

• Greenwich Hospital Association -Greenwich, CT · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 070018
• White Plains Hospital CenterWhite Plains, NY · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 330304

Practice locations

Addresses where Marianne Monahan is enrolled with Medicare (CMS data updated October 2, 2026).

• 1 Theall RdRye, NY 10580 (914) 848‑8888
• 210 Westchester AveWhite Plains, NY 10604 (914) 682‑0700
• 3030 Westchester AvePurchase, NY 10577 (914) 831‑4100
• 644 W Putnam AveGreenwich, CT 06830 (203) 622‑0303

Group practices

Medicare enrollment lists Marianne Monahan as a member of this group (CMS data updated October 2, 2026).

• Westchester Medical Group, P.C415 clinicians in the group

Specialties

• Nephrologyprimary
• Internal Medicinealso

Find other Nephrology doctors in New York →

Other nephrologists in New York

Clinicians with the same Medicare primary specialty in New York — not a recommendation.

• David J. Cohen, MD
• Sharmini Jayamaha, MD
• Anuj A. Patel, MD
• Mandip Panesar, MD
• Daniil Shimonov, MD
• Faisal Jamal, MD
• Moazam M. Cheema, MD
• Rohit Aloor, MD

All nephrologists in New York →

Other clinicians in Westchester Medical Group, P.C

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Adora-Ann C. Fou, MD
• Kelly N. Annunziato, PA
• Barry S. Kimmel, MD
• George O. Piccorelli, MD
• Catherine Shea, MD
• Emily M. Arduino, PA

Clinician information

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians