Evidence map›Paper›PMID 26493812›Full record

Trial reportOsteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA2016

Acute and 3-month effects of calcium carbonate on the calcification propensity of serum and regulators of vascular calcification: secondary analysis of a randomized controlled trial.

S M Bristow, G D Gamble, A Pasch, W C O'Neill, A Stewart, A M Horne, I R Reid

Open access · greenAbstract readRandomized Controlled Trial
PubMed Publisher
In one paragraph

Trial report in Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
8citing papers in PubMed, 1 pooled it
0.8field-weighted citation impact, top 27% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

8 citing papers in PubMed, 1 synthesis or guideline pooled it, 15 citations in OpenAlex.

  1. Pooled it
  2. Review
  3. Article
  4. Calcium Supplementation- Efficacy and Safety.Current osteoporosis reports · 2025
    Review
  5. Review
  6. Review
  7. Review
  8. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 4 institutions in 3 countries.

S M BristowUniversity of Auckland, Auckland, New Zealand.
G D GambleUniversity of Auckland, Auckland, New Zealand.
A PaschDepartment of Clinical Chemistry, University Hospital Bern, Inselspital, Bern, Switzerland.
W C O'NeillRenal Division, School of Medicine, Emory University, Atlanta, GA, USA.
A StewartUniversity of Auckland, Auckland, New Zealand.
A M HorneUniversity of Auckland, Auckland, New Zealand.
I R ReidUniversity of Auckland, Auckland, New Zealand. i.reid@auckland.ac.nz.
University of Auckland · NZAuckland District Health Board · NZEmory University · USUniversity Hospital of Bern · CH

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

summaryCalcium supplements have been associated with increased cardiovascular risk, but the mechanism is unknown. We investigated the effects of calcium supplements on the propensity of serum to calcify, based on the transition time of primary to secondary calciprotein particles (T50). Changes in serum calcium were related to changes in T50.

introductionCalcium supplements have been associated with increased cardiovascular risk; however, it is unknown whether this is related to an increase in vascular calcification.

methodsWe investigated the acute and 3-month effects of calcium supplements on the propensity of serum to calcify, based on the transition time of primary to secondary calciprotein particles (T50), and on three possible regulators of calcification: fetuin-A, pyrophosphate and fibroblast growth factor-23 (FGF23). We randomized 41 postmenopausal women to 1 g/day of calcium as carbonate, or to a placebo containing no calcium. Measurements were performed at baseline and then 4 and 8 h after their first dose, and after 3 months of supplementation. Fetuin-A, pyrophosphate and FGF23 were measured in the first 10 participants allocated to calcium carbonate and placebo who completed the study.

resultsT50 declined in both groups, the changes tending to be greater in the calcium group. Pyrophosphate declined from baseline in the placebo group at 4 h and was different from the calcium group at this time point (p = 0.04). There were no other significant between-groups differences. The changes in serum total calcium from baseline were significantly related to changes in T50 at 4 h (r = -0.32, p = 0.05) and 8 h (r = -0.39, p = 0.01), to fetuin-A at 3 months (r = 0.57, p = 0.01) and to pyrophosphate at 4 h (r = 0.61, p = 0.02).

conclusionsThese correlative findings suggest that serum calcium concentrations modulate the propensity of serum to calcify (T50), and possibly produce counter-regulatory changes in pyrophosphate and fetuin-A. This provides a possible mechanism by which calcium supplements might influence vascular calcification.

Indexed as

Agedalpha-2-HS-GlycoproteinBiomarkersBone Density Conservation AgentsCalciumCalcium CarbonateCalcium CitrateDietary SupplementsDiphosphatesDrug Administration ScheduleFemaleFibroblast Growth Factor-23Fibroblast Growth FactorsHumansMiddle AgedVascular Calcificationalpha-2-HS-GlycoproteinBiomarkersBone Density Conservation AgentsCalciumCalcium CarbonateCalcium CitrateDiphosphatesdiphosphoric acidFGF23 protein, humanFibroblast Growth Factor-23Fibroblast Growth FactorsCalcificationCalciumCardiovascular

Identifiers

PMID26493812
OpenAlexW2122194928

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.