Biomarkers · Hematology
Hemoglobin Concentration
U-shaped: both low and high values carry risk. In NHANES 1999–2018 with linked mortality to 2019, each standard deviation is associated with a hazard ratio of 0.80. U-shaped: slope not comparable
NHANES, our fit with 95% CIPublished curve
Hazard ratios relative to each curve's own reference value, so the two curves need not cross 1 at the same point. The dotted vertical line marks the NHANES median.
NHANES hazard per SD0.8095% CI 0.78–0.83 · 49,105 adults, 7,188 deaths
Published hazard ratio1.41top vs bottom quarter (95% CI 1.25–1.59) · Cardiovascular Health Study (CHS)
Where people sit
Population percentiles (g/dL) by sex and age band. Cycle or source as recorded in the catalogue.
| Sex | Age | 5th | 25th | Median | 75th | 95th | n | Cycle / source |
|---|---|---|---|---|---|---|---|---|
| All | 20-39 | 11.9 | 13.4 | 14.4 | 15.4 | 16.8 | 2,710 | 2017-2018 |
| All | 40-59 | 12.0 | 13.5 | 14.4 | 15.4 | 16.8 | 2,670 | 2017-2018 |
| All | 60+ | 11.5 | 13.0 | 14.0 | 15.0 | 16.5 | 2,820 | 2017-2018 |
| All | all | 11.8 | 13.3 | 14.3 | 15.3 | 16.7 | 8,200 | 2017-2018 |
| Men | all | 13.2 | 14.4 | 15.2 | 16.0 | 17.1 | 3,980 | 2017-2018 |
| Women | all | 11.4 | 12.6 | 13.4 | 14.2 | 15.3 | 4,220 | 2017-2018 |
What studies found when this marker was changed
Effects on the biomarker reported in the cited studies. They describe what happened in those populations, not a recommendation for anyone. See all catalogued interventions.
| Type | Intervention | Reported effect | Evidence | Source |
|---|---|---|---|---|
| clinical | Chronic occult gastrointestinal blood loss (Colorectal lesion / PUD) | -3.0 to -8.0 g/dL severe anemia (<8.0 g/dL) | clinical guideline | Goddard AF, et al. Gut. 2011;60:1309-1316. |
| clinical | Polycythemia vera (JAK2 V617F mutation) or severe chronic hypoxia | +4.0 to +8.0 g/dL dangerous hyperviscosity (>18.5 g/dL) | clinical guideline | Tefferi A, et al. Am J Hematol. 2018;93:1424-1441. |
| exercise | Altitude / hypoxic conditioning protocol | +0.5 to +1.2 g/dL physiological increase | rct | Levine BD, et al. J Appl Physiol. 1997;83:102-112. |
| nutraceutical | Intravenous / oral iron repletion in iron deficiency anemia | +2.0 to +4.0 g/dL normalization | meta-analysis | Auerbach M, et al. Am J Hematol. 2016;91:31-38. |
| pharmacologic | Erythropoiesis-stimulating agents (ESA) / HIF-PH inhibitors (Roxadustat) in CKD anemia | +1.5 to +3.0 g/dL target correction (aiming for 10-11.5 g/dL) | rct | Chen N, et al. N Engl J Med. 2019;381:1001-1010. |
| supplement | Targeted elemental iron or erythropoiesis-stimulating cofactors when deficient | Normalizes hemoglobin to optimal 13.5-16.5 g/dL (men) and 12.0-15.0 g/dL (women) | RCT | National Center for Health Statistics. National Health and Nutrition Examination… |
Sources
- Hazard curve: Recalculated from mortality_association (HR=1.41 quartile_extreme); per-SD log(HR)=0.2681.
- Zakai NA, et al. A prospective study of anemia and all-cause mortality in community-dwelling older adults: the Cardiovascular Health Study. Arch Intern Med. 2005;165(19):2214-2220.
- Empirical curve: our Cox model with age and sex, NHANES 1999–2018 with linked mortality to 2019.