Is a hematocrit of 47.2% normal for an adult and what follow‑up is recommended?

Hematocrit 47.2% Assessment

A hematocrit of 47.2% falls within the normal physiological range for adult males and postmenopausal females (47 ± 6%), but is mildly elevated for premenopausal women (normal 41 ± 5%); no immediate intervention is required, but the value should be interpreted in the context of sex, altitude, and clinical symptoms. 1, 2

Normal Reference Ranges by Sex and Age

For adult males and postmenopausal females:

• Normal hematocrit: 47 ± 6% (range approximately 41–53%) 2
• Normal hemoglobin: 15.5 ± 2.0 g/dL 2

For premenopausal (menstruating) females:

• Normal hematocrit: 41 ± 5% (range approximately 36–46%) 2
• Normal hemoglobin: 14.0 ± 2.0 g/dL 2

Your value of 47.2% is:

• Normal for males/postmenopausal females 2
• Mildly elevated (approximately 95th percentile) for premenopausal women 1

Altitude Adjustment Required

If you live at altitude ≥3,000 feet (914 meters), your hematocrit should be interpreted with upward adjustment: 3

• At 1,500 meters: add +0.5 g/dL to hemoglobin (approximately +1.5% to hematocrit) 1, 3
• At 2,000 meters: add +0.8 g/dL to hemoglobin (approximately +2.4% to hematocrit) 1, 3
• At 4,000 meters: normal male hematocrit averages 52.7% (range 45–61%) 4

Failure to adjust for altitude leads to overdiagnosis of polycythemia and underdiagnosis of anemia. 3

When to Investigate Further

Repeat measurement is warranted if: 1

• You are a premenopausal woman (47.2% exceeds typical female range) 1, 2
• You have symptoms of hyperviscosity (headache, blurred vision, confusion, bleeding) 1
• You have documented progressive rise over 6 months 1
• You have thrombocytosis, leukocytosis, or splenomegaly 1

Initial laboratory workup should include: 1

• Complete blood count with red cell indices (MCV, MCH, MCHC, RDW) 1
• Serum ferritin and transferrin saturation (iron deficiency can coexist with erythrocytosis) 1
• Reticulocyte count 1
• White blood cell differential and platelet count 1

Diagnostic Thresholds for True Erythrocytosis

True erythrocytosis requiring JAK2 mutation testing is defined as: 1

• Hemoglobin >18.5 g/dL in men OR >16.5 g/dL in women 1
• AND hematocrit >52% in men OR >48% in women 1

Your value of 47.2% does NOT meet these thresholds for mandatory polycythemia vera workup. 1

When Phlebotomy Is Indicated

Therapeutic phlebotomy is indicated ONLY when ALL of the following are present: 1

• Hemoglobin >20 g/dL AND hematocrit >65% 1
• Documented hyperviscosity symptoms 1
• Adequate hydration confirmed 1
• Iron deficiency excluded 1

Your value of 47.2% is far below the 65% threshold; phlebotomy is NOT indicated and would be harmful. 1

Clinical Significance of Borderline-High Hematocrit

Even hematocrit values in the high-normal range (45–49%) are associated with increased cardiovascular risk: 5

• In the Framingham Heart Study, hematocrit >45% (compared to <40%) was associated with a 78% increased risk of developing heart failure over 20 years (HR 1.78,95% CI 1.15–2.75) 5
• This association persisted after adjusting for cardiovascular risk factors and remained significant in nonsmokers 5

However, in chronic kidney disease, hematocrit 33–36% is associated with 10% reduced mortality compared to 30–33%, suggesting context-dependent optimal ranges. 2, 6

Recommended Follow-Up

For asymptomatic individuals with hematocrit 47.2%: 1

• If male or postmenopausal female at sea level: No immediate action required; routine monitoring 2
• If premenopausal female: Repeat measurement to confirm; if persistent, obtain complete blood count with indices and iron studies 1
• If living at altitude ≥3,000 feet: Apply altitude adjustment before determining if value is abnormal 3
• Serial measurements every 6–12 months are appropriate for borderline values to detect progression 1

Common Pitfalls to Avoid

Do not perform phlebotomy for hematocrit <65% without documented hyperviscosity symptoms and adequate hydration. 1

Do not overlook coexisting iron deficiency—serum ferritin and transferrin saturation must be checked, as iron deficiency mimics hyperviscosity but requires iron supplementation, not phlebotomy. 1

Do not use sea-level reference ranges for patients living at altitude ≥3,000 feet—this leads to misdiagnosis. 3

Hemoglobin is more reliable than hematocrit for monitoring because hematocrit can falsely increase 2–4% with prolonged sample storage, while hemoglobin remains stable. 1, 2