Biomarkers · Electrolytes & Minerals
Serum Calcium
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 0.95. 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 SD0.9595% CI 0.93–0.97 · 48,333 adults, 7,023 deaths
Published hazard ratio1.34top vs bottom quarter (95% CI 1.15–1.56) · NHANES III Prospective Cohort
Where people sit
Population percentiles (mg/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 | 8.90 | 9.30 | 9.50 | 9.70 | 10.1 | 2,700 | 2017-2018 |
| All | 40-59 | 8.80 | 9.20 | 9.40 | 9.60 | 10.0 | 2,650 | 2017-2018 |
| All | 60+ | 8.70 | 9.10 | 9.40 | 9.60 | 10.0 | 2,800 | 2017-2018 |
| All | all | 8.80 | 9.20 | 9.40 | 9.70 | 10.0 | 8,150 | 2017-2018 |
| Men | all | 8.90 | 9.20 | 9.50 | 9.70 | 10.1 | 3,950 | 2017-2018 |
| Women | all | 8.80 | 9.10 | 9.40 | 9.60 | 10.0 | 4,200 | 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 | Targeted parathyroidectomy in primary hyperparathyroidism | Permanent curative normalization to 9.2-9.8 mg/dL | clinical guideline | Bilezikian JP, et al. J Clin Endocrinol Metab. 2014;99:3561-3569. |
| clinical | Malignancy-associated hypercalcemia (PTHrP secretion / osteolytic bone mets) | +2.0 to +6.0 mg/dL dangerous hypercalcemia (>12.0 mg/dL) | clinical guideline | Stewart AF. N Engl J Med. 2005;352:373-379. |
| diet | Dietary calcium optimization (1000-1200 mg/day from whole foods) with Vitamin D3 | Restores physiological homeostasis without vascular calcification | meta-analysis | Bolland MJ, et al. BMJ. 2015;351:h4183. |
| nutraceutical | Massive unmonitored Vitamin D intoxication (>50,000 IU/day chronic) | +2.0 to +4.5 mg/dL hypercalcemia and nephrocalcinosis | systematic review | Marcinowska-Suchowierska E, et al. Front Endocrinol. 2018;9:550. |
| pharmacologic | Calcimimetics (Cinacalcet 30-90 mg) in secondary hyperparathyroidism | -0.8 to -1.5 mg/dL reduction to target range | rct | Chertow GM, et al. N Engl J Med. 2004;350:1516-1525. |
Sources
- Hazard curve: Recalculated from mortality_association (HR=1.34 quartile_extreme); per-SD log(HR)=0.2284.
- Foley RN, et al. Serum calcium and phosphorus levels and mortality in the US general population: NHANES III. Kidney Int. 2009;76(7):767-772.
- Empirical curve: our Cox model with age and sex, NHANES 1999–2018 with linked mortality to 2019.