MARZENA GIENIUSZ, M.D. appears in the CMS NPPES registry as a Geriatric Medicine (Internal Medicine) Physician provider holding M.D. credentials at 865 NORTHERN BLVD STE 201, GREAT NECK, NY, 11021, with a listed phone of (516) 708-2520. NPI 1366886640 was issued on 04/17/2013. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GIENIUSZ most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 2,087 prescription claims written by this provider, covering 261 Medicare beneficiaries and totaling roughly $139K in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 91.2532/100 for the 2023 performance year (Quality 74.9203), compared with the national average of 83.1.

Geriatric Medicine (Internal Medicine) Physician is a narrow specialty nationwide, with 4,161 enrolled providers across 52 states and an average of 4,450 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.