Fibrinogen

ND-recommended test reviewed: fibrinogen.
Indications reviewed: cardiovascular risk stratification; no bleeding or clotting disorder concern present.
Not ordered. Rationale discussed: fibrinogen adds only marginal predictive value over standard cardiovascular risk factors; not recommended for this purpose by any guideline reviewed. Ref: Kaptoge et al 2012 (Emerging Risk Factors Collaboration), NEJM.
Patient informed test available privately via ND. Patient given info page: https://labs.ajaxharwoodclinic.com/fibrinogen/patient
Revisit if: new bleeding, easy bruising, or a clotting concern requiring a coagulation workup.

Indicated when

• —Part of a coagulation work-up for suspected bleeding disorder, disseminated intravascular coagulation or severe liver disease, alongside PT/INR and aPTT (standard haematology practice; not sourced in this batch, see evidence_notes)

Not indicated when

• —Cardiovascular risk assessment or stratification, alone or alongside cholesterol testing; adding fibrinogen to conventional risk factors produced only a small improvement in risk prediction in a large individual-participant meta-analysis, similar to CRP [1]
• —Routine addition to a wellness or 'inflammation' panel

Why not

In a meta-analysis of 52 prospective studies with over 246,000 participants, adding fibrinogen to conventional cardiovascular risk factors improved a standard measure of risk prediction (the C-index) by only 0.0027, a small increment, and no major cardiovascular guideline was found in this session that recommends routine fibrinogen measurement for cardiovascular risk stratification [1]. Fibrinogen also rises non-specifically with infection, inflammation, smoking, and pregnancy, which further limits its usefulness as an isolated cardiovascular marker.

Better first step

Standard cardiovascular risk assessment (blood pressure, lipids, smoking status, diabetes status, family history) is the appropriate first step; fibrinogen does not add enough predictive value to change that assessment [1].

Typical ND rationale

An ND may order fibrinogen reasoning that, as a clotting factor and marker of inflammation, an elevated level could flag increased cardiovascular risk that standard cholesterol testing misses.

Ontario coverage & CONO orderability

OHIP status

insured

Listed by name in the 2026 Schedule of Benefits for Laboratory Services (L402 Fibrinogen, quantitative, fee $6.81). Insured when ordered by a physician, midwife, or NP who has clinically assessed the patient; the same test ordered by an ND is not insured and is billed privately (Reg. 552 s.22(1); SOB-LS 2026 preamble). This coverage applies to fibrinogen testing generally; it is not specific to cardiovascular risk assessment, which is not this test's validated use.

CONO orderable

Yes — CONO list #64

CONO list item 64, blood: 'Fibrinogen semi-quantitative and quantitative.'

Linked conditions

• dyslipidemia ↗

Counselling script

“Fibrinogen only adds a very small amount to how well we can predict cardiovascular risk once we already have standard factors like blood pressure and cholesterol, so it's not part of how I assess heart risk. It's a useful test in a different context, for investigating bleeding or clotting problems, but that's not what we're looking at today.”

Revisit if

• —New bleeding, easy bruising, or suspected clotting disorder (a different clinical question)
• —New family history of premature cardiovascular disease warranting standard risk reassessment

References

1. [1]Emerging Risk Factors Collaboration (2012). C-reactive protein, fibrinogen, and cardiovascular disease prediction. linkolder guidelineAdding fibrinogen to conventional risk factors produced only a small improvement in risk discrimination (C-index +0.0027)
2. [2]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026) - L402 Fibrinogen, quantitative. linkFibrinogen, quantitative (L402) is listed by name in the 2026 OHIP Schedule of Benefits for Laboratory Services
3. [3]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkCommunity lab tests are insured only when ordered under the Schedule by an authorized prescriber
4. [4]Government of Ontario (e-Laws) (2026). Health Insurance Act, R.R.O. 1990, Reg. 552: General, s. 22 (insured laboratory services). linkA lab test is insured only when ordered by a physician, midwife, or NP who has clinically assessed the patient
5. [5]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkTests ordered by anyone other than an authorized provider, including NDs, are not insured services