Elsevier

The Lancet

Volume 356, Issue 9245, 2 December 2000, Pages 1871-1875
The Lancet

Fast track — Articles
Effects of pravastatin in 3260 patients with unstable angina: results from the LIPID study*

https://doi.org/10.1016/S0140-6736(00)03257-8Get rights and content

Summary

Background

The LIPID study is a major trial of secondary prevention of coronary-heart-disease events that includes hospital admission with unstable angina (as well as myocardial infarction) as a qualifying event. In this substudy of LIPID, we compared subsequent cardiovascular risks and the effects of pravastatin in patients with previous unstable angina or previous myocardial infarction.

Methods

3260 patients diagnosed with unstable angina and 5754 with acute myocardial infarction 3–36 months previously were randomly assigned 40 mg pravastatin daily or placebo over a mean of 6·0 years. The risk reduction of a range of cardiovascular events was estimated by means of the hazard ratio in Cox's proportional hazards model.

Findings

Among patients assigned placebo, survival in the two diagnosis groups was similar. The relative risk reduction for mortality with pravastatin was 20·6% in the myocardial infarction group and 26·3% in the unstable angina group (p=0·55). Pravastatin significantly reduced the rates of all prespecified coronary endpoints in the myocardial infarction group. In patients with previous unstable angina, coronary heart disease mortality, total mortality, myocardial infarction, a need for coronary revascularisation, the number of admissions to hospital, and the number of days in hospital were significantly lower with pravastatin. Overall, hospital admission for unstable angina was the most common endpoint (24·6% of the placebo group; 22·3% of the pravastatin group).

Interpretation

Patients who have survived acute myocardial infarction or unstable angina have a similar long-term prognosis, a high occurrence of subsequent unstable angina, and benefit similarly from therapy with pravastatin.

Introduction

The number of patients with unstable angina who require admission to monitored beds for hospital treatment is increasing and, in many countries, is higher than the number of patients admitted with acute myocardial infarction.1 However, although these patients have similar pathophysiology,2 scientific data relating to the long-term prevention of further coronary-heart-disease events has generally been limited to the patients with myocardial infarction. For patients with unstable angina, the place of cholesterol-lowering therapy for secondary prevention of coronary-heart-disease events has had little attention.

Overall results in the Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) study—the largest trial of lipid-modifying therapy with a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor—have been presented.3 This is the only trial of prevention to include patients admitted to hospital with unstable angina as well as those with previous myocardial infarction. The trial design included stratification by this qualifying diagnosis, since whether the effects of treatment would be the same in both groups of patients was not known.

In this substudy, our objectives were: (1) to ascertain the long-term risks of major cardiovascular events in patients qualifying for the LIPID study with unstable angina; (2) to compare the risks of major cardiovascular events in patients qualifying with unstable angina with those in patients who had had myocardial infarction; and (3) to compare the effects of pravastatin in the patients with previous unstable angina with those in the patients with previous acute myocardial infarction.

Section snippets

Patients

The design of the LIPID study has been described in detail elsewhere.4 9014 patients (7498 men and 1516 women, aged 31–75 years) were recruited in 87 centres in Australia and New Zealand between June, 1990, and December, 1992. Patients had had an acute myocardial infarction or a hospital discharge diagnosis of unstable angina 3–36 months before randomisation. Patients who had experienced both acute myocardial infarction and hospital admission for unstable angina within this period were included

Results

We studied3260 patients (2605 men, 655 women) with unstable angina, which occurred a median of 18·8 months (IQR 8·6–36·7) previously, and 5754 (4893 men, 861 women) who had had acute myocardial infarction a median of 14·6 months (8·2–25·8 months) previously.

There were differences in the baseline characteristics of these groups (table 1). Those stratified by the diagnosis of unstable angina included a higher proportion of women, and on average, were slightly older than the patients who had had

Discussion

The results of the LIPID study show that patients who have survived acute myocardial infarction and those who have survived unstable angina have a similar long-term prognosis, although this may have been influenced by selection criteria, such as exclusion of patients with poor left-ventricular function. Although there were differences in some risk factors at baseline, these factors were well balanced by treatment within these groups, and they did not affect the analysis of the effects of

References (22)

  • E Braunwald et al.

    Unstable angina: diagnosis and management. Clinical Practice Guideline Number 10, AHCPR publication 94-0602

    (1994)
  • Cited by (78)

    • Efficacy and safety of long-term treatment with statins for coronary heart disease: A Bayesian network meta-analysis

      2016, Atherosclerosis
      Citation Excerpt :

      Finally, 88 studies were included (Supplemental Fig. 1). Of the 88 studies, 34 studies [24–57] reported TC, 45 studies [24–54,56–69] reported LDL-C, 33 studies [24,26–33,35–38,40–46,48,49,51–53,55–57,59,62,64,68,69] reported HDL-C, 34 studies [24,26–33,35–38,40,42–57,62,64,68,69] reported TG, 13 studies [25,39,40,50,63,66,70–76] reported AE, 67 studies [24–27,29–39,41–45,59–63,65–67,70–108] reported CHD mortality and 55 studies [25–29,31–35,38–41,44,59–62,66,69–83,85,86,90–92,94–96,98–100,103–111] reported all-cause mortality. The characteristics of eligible studies are summarized in Table 1.

    • Lipoprotein Metabolism and the Treatment of Lipid Disorders

      2015, Endocrinology: Adult and Pediatric
    • Accuracy of national mortality codes in identifying adjudicated cardiovascular deaths

      2011, Australian and New Zealand Journal of Public Health
    View all citing articles on Scopus
    *

    Deceased

    View full text