Evidence mapPaperPMID 25915488Full record

Trial reportPloS one2015

Caloric restriction decreases orthostatic tolerance independently from 6° head-down bedrest.

John P Florian, Friedhelm J Baisch, Martina Heer, James A Pawelczyk

Open access · goldAbstract readRandomized Controlled Trial
In one paragraph

Trial report in PloS one, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
15citing papers in PubMed, 1 pooled it
0.9field-weighted citation impact, top 25% 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

15 citing papers in PubMed, 1 synthesis or guideline pooled it, 20 citations in OpenAlex.

  1. Pooled it
  2. Effects of short-term hypercaloric nutrition on orthostatic tolerance in healthy individuals: a randomized controlled crossover study.Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2022
    Trial
  3. Review
  4. Article
  5. Review
  6. Energy metabolism and syncope.Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2022
    Article
  7. Review
  8. Article
  9. Article
  10. Review
  11. Review
  12. Review
  13. Article
  14. Review
  15. 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

4 authors at 2 institutions in 1 country.

John P FlorianNavy Experimental Diving Unit, Panama City, Florida, United States of America.
Friedhelm J BaischDLR-Institute of Aerospace Medicine, Cologne, Germany.
Martina HeerDLR-Institute of Aerospace Medicine, Cologne, Germany.
James A PawelczykDepartment of Kinesiology, Noll Laboratory, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
Pennsylvania State University · USUnited States Department of the Navy · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Astronauts consume fewer calories during spaceflight and return to earth with an increased risk of orthostatic intolerance. Whether a caloric deficiency modifies orthostatic responses is not understood. Thus, we determined the effects of a hypocaloric diet (25% caloric restriction) during 6° head down bedrest (an analog of spaceflight) on autonomic neural control during lower body negative pressure (LBNP). Nine healthy young men completed a randomized crossover bedrest study, consisting of four (2 weeks each) interventions (normocaloric bedrest, normocaloric ambulatory, hypocaloric bedrest, hypocaloric ambulatory), each separated by 5 months. Muscle sympathetic nerve activity (MSNA) was recorded at baseline following normocaloric and hypocaloric interventions. Heart rate (HR) and arterial pressure were recorded before, during, and after 3 consecutive stages (7 min each) of LBNP (-15, -30, -45 mmHg). Caloric and posture effects during LBNP were compared using two-way ANOVA with repeated measures. There was a strong trend toward reduced basal MSNA following caloric restriction alone (normcaloric vs. hypocaloric: 22±3 vs. 14±4 burst/min, p = 0.06). Compared to the normocaloric ambulatory, both bedrest and caloric restriction were associated with lower systolic blood pressure during LBNP (p<0.01); however, HR responses were directionally opposite (i.e., increase with bedrest, decrease with caloric restriction). Survival analysis revealed a significant reduction in orthostatic tolerance following caloric restriction (normocaloric finishers: 12/16; hypocaloric finishers: 6/16; χ2, p = 0.03). Caloric restriction modifies autonomic responses to LBNP, which may decrease orthostatic tolerance after spaceflight.

Indexed as

AdultArterial PressureAstronautsBed RestCaloric RestrictionCross-Over StudiesDiet, ReducingHeart RateHumansLower Body Negative PressureMaleMuscle, SkeletalOrthostatic IntolerancePostureSpace FlightSympathetic Nervous System

Identifiers

PMID25915488
PMCPMC4411149
OpenAlexW2031777634

What Socratic holds

Textmetadata
LicenceCC0
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 Socratic graph.