Evidence map›Paper›PMID 8550838›Full record

Trial reportThe Journal of clinical investigation1996

Vitamin C improves endothelium-dependent vasodilation in patients with non-insulin-dependent diabetes mellitus.

H H Ting, F K Timimi, K S Boles, S J Creager, P Ganz, M A Creager

Open access · bronzeAbstract readClinical TrialControlled Clinical Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in The Journal of clinical investigation, 1996. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 132 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
132citing papers in PubMed, 1 pooled it
24.0field-weighted citation impact, top 1% 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

132 citing papers in PubMed, 1 synthesis or guideline pooled it, 872 citations in OpenAlex.

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  11. Dietary supplement with vitamin C prevents nitrate tolerance.The Journal of clinical investigation · 1998
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  15. Oxidative Stress, Endothelial Dysfunction, andAntioxidants & redox signaling · 2024
    Review
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72 more citing papers are in PubMed but not listed here.

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

6 authors at 2 institutions in 1 country.

H H TingVascular Medicine and Atherosclerosis Unit, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
F K Timimi
K S Boles
S J Creager
P Ganz
M A Creager
Harvard University · USBrigham and Women's Hospital · US

Funding

VASCULAR DISEASE ACADEMIC AWARDK07HL002663 · NHLBI · BRIGHAM AND WOMEN'S HOSPITAL · PI CREAGER, MARK A · 1991 to 1995
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NHLBI NIH HHS HL-02663NHLBI NIH HHS HL-48743
6 · The paper itself

Abstract

Endothelium-dependent vasodilation is impaired in humans with diabetes mellitus. Inactivation of endothelium-derived nitric oxide by oxygen-derived free radicals contributes to abnormal vascular reactivity in experimental models of diabetes. To determine whether this observation is relevant to humans, we tested the hypothesis that the antioxidant, vitamin C, could improve endothelium-dependent vasodilation in forearm resistance vessels of patients with non-insulin-dependent diabetes mellitus. We studied 10 diabetic subjects and 10 age-matched, nondiabetic control subjects. Forearm blood flow was determined by venous occlusion plethysmography. Endothelium-dependent vasodilation was assessed by intraarterial infusion of methacholine (0.3-10 micrograms/min). Endothelium-independent vasodilation was measured by intraarterial infusion of nitroprusside (0.3-10 micrograms/min) and verapamil (10-300 micrograms/min). Forearm blood flow dose-response curves were determined for each drug before and during concomitant intraarterial administration of vitamin C (24 mg/min). In diabetic subjects, endothelium-dependent vasodilation to methacholine was augmented by simultaneous infusion of vitamin C (P = 0.002); in contrast, endothelium-independent vasodilation to nitroprusside and to verapamil were not affected by concomitant infusion of vitamin C (P = 0.9 and P = 0.4, respectively). In nondiabetic subjects, vitamin C administration did not alter endothelium-dependent vasodilation (P = 0.8). We conclude that endothelial dysfunction in forearm resistance vessels of patients with non-insulin-dependent diabetes mellitus can be improved by administration of the antioxidant, vitamin C. These findings support the hypothesis that nitric oxide inactivation by oxygen-derived free radicals contributes to abnormal vascular reactivity in diabetes.

Indexed as

AdultAntioxidantsAscorbic AcidDiabetes Mellitus, Type 2Endothelium, VascularFemaleHumansMaleMatched-Pair AnalysisMethacholine ChlorideMiddle AgedNitroprussideVasodilationVasodilator AgentsVerapamilAntioxidantsAscorbic AcidMethacholine ChlorideNitroprussideVasodilator AgentsVerapamil

Identifiers

PMID8550838
PMCPMC507058
OpenAlexW1975974235

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.