Medicare Enrolled
Dr. Patrick Brennan, D.O.
Family Medicine · South Lyon, MI
Practice pattern: Clinical Cardiology
— Primarily office-based clinical cardiology
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Brennan from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
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What this data tells you about Dr. Brennan
Dr. Patrick Brennan is a family medicine specialist in South Lyon, MI, with 21 years of NPI registration. Based on federal Medicare data, Dr. Brennan performed 2,704 Medicare services in 2023. These records do not provide a deduplicated patient total.
Between the years covered by Open Payments, Dr. Brennan received a total of $641 from 11 pharmaceutical and/or device companies across 38 payment records. A record can group multiple payments. These transfers are publicly reported through CMS Open Payments. Disclosure alone does not establish their effect on care. A reliable breakdown by payment category is not available in this snapshot. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Brennan is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
✓ 21 years of NPI registration
▲ Top 4% volume in MI
$641 industry payments
Medicare Practice Summary — 2023
Medicare Utilization ↗2,704
Medicare services
Top 4% in MI for family medicine
Not available
Unique patients (not deduplicated)
$32
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
325 | $88 | $292 |
| Blood draw (venipuncture) Insertion of a needle into a vein to collect a blood sample. |
299 | $8 | $16 |
| Comprehensive metabolic blood panel A blood test that measures a group of chemicals, including glucose, electrolytes, and kidney and liver function markers. |
241 | $10 | $31 |
| Complete blood count (CBC) with differential An automated laboratory test that measures the levels of red blood cells, white blood cells, and platelets in the blood, including a breakdown of the different types of white blood cells. |
227 | $8 | $20 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
188 | $63 | $206 |
| Annual wellness visit, follow-up A follow-up annual wellness visit that includes a personalized prevention plan of service. |
135 | $128 | $298 |
| Lipid panel (cholesterol and triglycerides) A blood test that measures cholesterol and triglyceride levels. |
127 | $13 | $40 |
| Magnesium level test A blood test to measure the amount of magnesium in your body. This helps check for magnesium deficiency or excess. |
103 | $7 | $30 |
| Hemoglobin A1c test (diabetes monitoring) A blood test that measures your average blood sugar levels over the past two to three months. |
88 | $9 | $25 |
| Thyroid stimulating hormone (TSH) test A blood test that measures the level of thyroid stimulating hormone to evaluate thyroid function. |
83 | $16 | $50 |
| Uric acid level test A blood test that measures the level of uric acid in your body. Uric acid is a waste product formed when the body breaks down purines. |
75 | $4 | $13 |
| Erythrocyte sedimentation rate (ESR) test A blood test that measures how quickly red blood cells settle in a test tube to detect inflammation in the body. This specific method is performed manually rather than using an automated machine. |
72 | $4 | $18 |
| Free thyroxine (T4) test A blood test that measures the level of free thyroxine, a thyroid hormone, in the bloodstream. |
62 | $9 | $20 |
| Cardiac enzyme level (CK-MB) test A blood test that measures the total level of creatine kinase, specifically the cardiac enzyme fraction, to help evaluate heart muscle damage. |
60 | $6 | $13 |
| Automated urinalysis An automated laboratory test performed on a urine sample to analyze its chemical and physical properties. The procedure uses machinery to detect various substances and cells within the urine. |
53 | $2 | $5 |
| Natriuretic peptide level test A blood test that measures the level of natriuretic peptide, a protein produced by the heart and blood vessels. |
51 | $38 | $79 |
| Flu vaccine administration This procedure involves the administration of the influenza virus vaccine. It covers the process of delivering the vaccine to the patient. |
49 | $31 | $50 |
| Flu vaccine, high-dose High-dose seasonal influenza vaccine for adults aged 65 and older. Contains four times the antigen of standard-dose flu vaccines (60 mcg per strain), split-virus formulation, preservative-free, single-dose syringe. |
43 | $72 | $122 |
| Ferritin level test (iron stores) A blood test that measures the level of ferritin, a protein that stores iron in the body. |
37 | $13 | $28 |
| C-reactive protein test (inflammation marker) A blood test that measures the level of C-reactive protein to detect the presence of infection or inflammation in the body. |
31 | $5 | $10 |
| Urine microalbumin test (kidney screening) A laboratory test that measures the amount of microalbumin, a small protein, in a urine sample. This test is used to detect early signs of kidney damage. |
30 | $5 | $12 |
| Creatinine test (kidney function) A blood test that measures the amount of creatinine to assess kidney function or detect muscle injury. |
30 | $5 | $11 |
| Iron level test | 30 | $6 | $25 |
| Urine culture, bacterial colony count A laboratory test that measures the number of bacteria growing in a urine sample to help identify infections. |
30 | $8 | $16 |
| Vitamin D level test A blood test to measure the amount of Vitamin D-3 in your body. |
29 | $29 | $60 |
| Phosphate level test A blood test that measures the amount of phosphate in your body. Phosphate is a mineral that helps keep bones and teeth strong. |
29 | $5 | $9 |
| Transferrin level test A blood test that measures the amount of transferrin, a protein that binds to and transports iron in the body. |
29 | $12 | $26 |
| Parathyroid hormone level test A blood test that measures the amount of parathyroid hormone in your body. This hormone helps regulate calcium levels in the blood and bones. |
28 | $40 | $83 |
| PSA test (prostate cancer screening) | 25 | $18 | $40 |
| Vitamin B-12 level test A blood test that measures the amount of vitamin B-12 in your body. |
24 | $15 | $60 |
| Electrocardiogram (EKG), 12-lead A standard heart rhythm test using at least 12 leads to record electrical activity. A healthcare provider interprets the results and provides a written report. |
16 | $10 | $34 |
| Transitional care management services, moderate complexity Services provided to coordinate care during the transition from an inpatient or other facility setting back to the community. This includes follow-up and management of a health problem of at least moderate complexity. |
16 | $164 | $467 |
| Folic acid level test A blood test that measures the amount of folic acid in the serum. |
15 | $14 | $30 |
| Respiratory virus detection test A laboratory test using immunoassay techniques to detect the presence of severe acute respiratory syndrome coronavirus and influenza viruses. |
13 | $48 | $131 |
| New patient office visit (45-59 min) An initial office visit for a new patient lasting between 45 and 59 minutes. This code covers the total time spent by the physician or qualified healthcare professional on the date of the encounter. |
11 | $88 | $376 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. These counts do not measure clinical quality or years of experience.
Industry Payment Transparency
Open Payments through 2023 ↗$641
Total received (2018-2023)
Avg $107/year across 6 years
Top 36% in MI for family medicine
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
11
Companies
38
Payment records
Payments are publicly reported; disclosure does not establish legality · Not evidence of wrongdoing · How to interpret →
Payment categories are unavailable while the source breakdown is being rebuilt. Company and year totals do not identify how much belongs to each category.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2023
$56
2022
$145
2021
$97
2020
$12
2019
$225
2018
$105
Payments by company (2023)
PFIZER INC.
$38
Novo Nordisk Inc
$19
Top 3 companies account for 100.0% of 2023 payments
All-time payments by company (2018-2023) ›
Astellas Pharma US Inc
$198
PFIZER INC.
$184
Nestle HealthCare Nutrition Inc.
$47
Biohaven Pharmaceutical Holding Company Ltd.
$44
AstraZeneca Pharmaceuticals LP
$44
Novo Nordisk Inc
$34
GlaxoSmithKline, LLC.
$26
Biohaven Pharmaceuticals, Inc.
$22
Lilly USA, LLC
$18
Supernus Pharmaceuticals, Inc.
$13
Teva Pharmaceuticals USA, Inc.
$12
Top 3 companies account for 66.8% of all-time payments
Associated products mentioned in payments ›
AJOVY · BREZTRI · CHANTIX · COMIRNATY · ELIQUIS · LYRICA · NURTEC ODT · Ozempic · QELBREE · TRELEGY ELLIPTA · TRULICITY · ZENPEP
Should you be concerned? Industry payments are disclosed through CMS Open Payments. Disclosure alone does not establish their purpose, legality, or effect on care. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
Geographic Context
Family medicine physicians in nearby ZIP areas
1,219
County median income
$95,296
Nearest hospital to ZIP centroid (approximate)
HENRY FORD HEALTH BRIGHTON CENTER FOR RECOVERY
7.7 mi
7.7 mi
Data Sources
| Provider Registry | ✓ NPPES | NPPES snapshot; verify current record |
| Medicare Enrollment | ✓ PECOS | PECOS snapshot |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2023 |
| Disciplinary History | — Not included | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Brennan is a clinical cardiology specialist, with above-average Medicare volume (top 4% in MI), with 21 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Brennan experienced with office visit, established patient (30-39 min)?
Based on Medicare claims data, Dr. Brennan performed 325 office visit, established patient (30-39 min) services. These records cover Medicare fee-for-service activity, including eligible younger beneficiaries; they do not measure total practice volume or clinical quality.
Does Dr. Brennan receive payments from pharmaceutical companies?
Yes. Dr. Brennan received a total of $641 from 11 companies across 38 payment records. A record can group multiple payments. These transfers are publicly disclosed through CMS Open Payments. Disclosure alone does not establish their legality or effect on care. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Brennan's costs compare to other family medicine physicians in South Lyon?
Dr. Brennan's average Medicare payment per service is $32. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Brennan) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating the presence of registry, enrollment, activity or payment records, not verified experience or clinical quality. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Source publication dates and the snapshots loaded on this site can differ. Rebuilding a page does not refresh its source records. Check the Medicare reporting year and the payment interval shown above; consult the linked official sources for newer releases and current registry details. See our data freshness policy →
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About this page
This page combines public CMS records with calculated summaries and explanatory procedure labels. These transformations are not verbatim federal records. Sources: NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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