Elsevier

The Lancet

Volume 355, Issue 9206, 4 March 2000, Pages 773-778
The Lancet

Articles
Stress hyperglycaemia and increased risk of death after myocardial infarction in patients with and without diabetes: a systematic overview

https://doi.org/10.1016/S0140-6736(99)08415-9Get rights and content

Summary

Background

High blood glucose concentration may increase risk of death and poor outcome after acute myocardial infarction. We did a systematic review and metaanalysis to assess the risk of in-hospital mortality or congestive heart failure after myocardial infarction in patients with and without diabetes who had stress hyperglycaemia on admission.

Methods

We did two searches of MEDLINE for Englishlanguage articles published from 1966 to October, 1998, a computerised search of Science Citation Index from 1980 to September, 1998, and manual searches of bibliographies. Two searchers identified all cohort studies or clinical trials reporting in-hospital mortality or rates of congestive heart failure after myocardial infarction in relation to glucose concentration on admission. We compared the relative risks of in-hospital mortality and congestive heart failure in hyperglycaemic and normoglycaemic patients with and without diabetes.

Findings

14 articles describing 15 studies were identified. Patients without diabetes who had glucose concentrations more than or equal to range 6·1–8·0 mmol/L had a 3·9-fold (95% CI 2·9–5·4) higher risk of death than patients without diabetes who had lower glucose concentrations. Glucose concentrations higher than values in the range of 8·0–10·0 mmol/L on admission were associated with increased risk of congestive heart failure or cardiogenic shock in patients without diabetes. In patients with diabetes who had glucose concentrations more than or equal to range 10·0–11·0 mmol/L the risk of death was moderately increased (relative risk 1·7 [1·2–2·4]).

Interpretation

Stress hyperglycaemia with myocardial infarction is associated with an increased risk of in-hospital mortality in patients with and without diabetes; the risk of congestive heart failure or cardiogenic shock is also increased in patients without diabetes.

Introduction

An unusually high prevalence of glucosuria in patients without diabetes who have acute myocardial infarction was noted as far back as 1931.1 Since then, up to half of these patients with acute myocardial infarction have been recognised as having raised blood glucose concentrations.2, 3 Moreover, a positive association between hyperglycaemia at the time of the event and mortality from myocardial infarction has been noted.4

Although the mechanisms underlying this association are not fully understood, evidence that use of insulin to lower glucose concentrations decreases mortality in patients with diabetes who have myocardial infarction5 suggests that hyperglycaemia is not simply an epiphenomenon of the stress response mediated by cortisol and noradrenaline. In patients who have had myocardial infarction, the lack of insulin associated with hyperglycaemia may lead to a decrease of glycolytic substrate for cardiac muscle and excessive free fatty acids. These changes may reduce myocardial contractility at increased oxygen cost, lead to pump failure, and promote arrythmias.6 Consequently, hyperglycaemia at the time of myocardial infarction in patients with and without diabetes may be an important and potentially modifiable risk factor for poor outcome.

We systematically searched for, reviewed, and assessed published evidence on the association between stress hyperglycaemia and in-hospital mortality and congestive heart failure in patients with and without diabetes, admitted with myocardial infarction.

Section snippets

Selection of articles

Two independent researchers did a computerised MEDLINE search of published articles (from 1966 to October, 1998). One researcher was assisted by a medical librarian experienced in literature searches. We searched by the subject headings “blood glucose” and “myocardial infarction”, text words “hyperglycemia”, “euglycemia”, and “hypoglycemia”, and methodology terms (including subject headings “incidence”, “mortality”, “follow-up studies”, “cohort studies”, and “prognosis”, and text words “natural

Results

The two MEDLINE searches yielded 49 and 217 citations, respectively. From the titles, abstracts, or both, 49 of the 266 citations were thought to be relevant by one or both of the searchers (κ=0·77), and the full text of these articles was retrieved. After review of the full text, 19 articles from the MEDLINE search were judged relevant (for agreement between searchers κ=0·83). Two additional relevant articles were found by searching the bibliographies; the Science Citation Index search yielded

Discussion

We showed that patients without diabetes who have stress hyperglycaemia on admission for acute myocardial infarction are at increased risk of in-hospital mortality and congestive heart failure or cardiogenic shock. Several possible mechanisms may explain this observation.

First, hyperglycaemia is a reflection of relative insulin deficiency, which is associated with increased lipolysis and excess circulating free fatty acids; this effect may be exaggerated in cases of acute stress such as

References (46)

  • MF Oliver et al.

    Effects of glucose and fatty acids on myocardial ischaemia and arrythmias

    Lancet

    (1994)
  • KA McKibbon et al.

    Beyond ACP Journal Club: how to harness MEDLINE for prognosis problem

    ACP J Club

    (1995)
  • A Lakhdar et al.

    Prognostic importance of hyperglycaemia induced by stress after myocardial infarction

    BMJ

    (1984)
  • S Fava et al.

    The prognostic value of blood glucose in diabetic patients with acute myocardial infarction

    Diabetes Med

    (1996)
  • B Modan et al.

    Acute myocardial infarction: prognostic value of white blood cell count and blood glucose level

    JAMA

    (1975)
  • DB Jones et al.

    Glucose, insulin and platelet fatty acids following myocardial infarction: an association with infarct size

    Diabetes Metabol

    (1987)
  • KK Datey et al.

    Hyperglycemia after acute myocardial infarction: its relation to diabetes mellitus

    N Engl J Med

    (1967)
  • K Malmberg et al.

    Mortality prediction in diabetic patients with myocardial infarction: experiences from the DIGAMI study

    Cardiovasc Res

    (1997)
  • NG Soler et al.

    Myocardial infarction in diabetics

    QJM

    (1975)
  • M Lynch et al.

    Acute myocardial infarction in diabetic patients in the thrombolytic era

    Diabetes Med

    (1994)
  • JS Yudkin et al.

    Determinants of hospital admission and case fatality in diabetic patients with myocardial infarction

    Diabetes Care

    (1988)
  • L Rytter et al.

    Prevalence and mortality of acute myocardial infarction in patients with diabetes

    Diabetes Care

    (1985)
  • AK Bannerjee

    Blood sugar and prognosis of acute myocardial infarction in the elderly

    Br J Clin Pract

    (1986)
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