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Gastroenterology

Hiroyuki Aihara, MD

Works at hospitals in Jamaica Plain, MA · Boston, MA · Massachusetts

Summary

Dr. Hiroyuki Aihara, MD is a gastroenterologist at 75 Francis St, Boston, MA 02115. Phone: (617) 732-5500. Accepts Medicare assignment. In 2024, Hiroyuki Aihara had 391 Original Medicare patients and 698 services. NPI 1619395795. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Hiroyuki Aihara, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Hiroyuki Aihara accept Medicare assignment?
Yes. Medicare's clinician data says Hiroyuki Aihara accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Hiroyuki Aihara see?
In 2024, CMS data shows 391 Original Medicare patients and 698 services for Hiroyuki Aihara. This counts Original Medicare only and measures volume, not quality.
What is Hiroyuki Aihara's NPI number?
1619395795. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Hiroyuki Aihara, 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.

Original Medicare patients391
Services billed to Medicare698
Different services or procedures30
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Removal of polyps or growths of large bowel using an endoscope with mechanical snare (45385)152 services
  2. Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito (G0500)144 services
  3. Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)99 services
  4. Biopsy of large bowel using a flexible endoscope (45380)91 services
  5. Other procedure on large bowel (45399)41 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 cholesterol72%
  • High blood pressure70%
  • Arthritis41%
  • Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)37%
  • Ischemic heart disease26%
  • Diabetes24%

Hospitals where Hiroyuki Aihara works

Medicare's Facility Affiliation Data lists Hiroyuki Aihara 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.

Practice locations

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

Group practices

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

  • Brigham and Womens Physicians Organization Inc2,994 clinicians in the group

Specialties

Find other Gastroenterology doctors in Massachusetts →

Other gastroenterologists in Boston

Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.

All gastroenterologists in Boston →

Other clinicians in Brigham and Womens Physicians Organization Inc

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

Clinician information

CredentialMD
Graduation year1998 (28 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1619395795
CorrectionsReport an error or suggest an update →

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