Table 1

Characteristics of studies included in the meta-analysis

Source§Original designCountryStudy size (n)Mean age (years)Male (%)Mean follow-up (months)Diseases at baselineOutcomesCRP sample collectionAdjustmentsQuality problems*
Apple 20075CohortAmerica4573657574ACSDeath, F_CVD NF_CVD3.1hAge, sex, DM, renal disease3a, b, e
Bursi 20076CohortAmerica32975695212AMIHF, death6.1hAge, sex, comorbidity, peak cTnT, ECG, KC, MI, recurrent ischaemic events2a, f
Foussas 20077CohortGreece7869360.778.81STEMIFailed thrombolysis, F_CHD3.5hAge, DM, anterior MI, Killip class, BP, HR, failed thrombolysis, cTnI2b, c
Foussas 20088,BCohortGreece93434065.571.460STEMI, NSTE-ACSDeath4.3 h for STEMI, 8.7h for NSTE-ACSAge, sex, HBP, smoke, DM, angina, MI, angioplasty, CABG, HF, history of CVD or PAD, anterior STEMI, Killip class, time from index pain to treatment, cTnI, tHcy1c
Hartford 20079CohortSweden757166657375ACSDeath<24 h after admission3c, e, f
Jernberg 200410CohortSweden72616170.433.240NSTE-ACSDeath, MI5.7 hAge, DM, HBP, MI, HF, ECG, cTnT, NT-proBNP, cystatin C2b, c
Kavsak 200711CohortCanada446645996ACSDeath, readmission for AMI or HF3 hAge, sex, cTnI6a, b, c, d, e, f
Kilcullen 200712,ACohortUnited Kindom144829672.56112ACSDeath12–24 hAge, HF, MI, HR, BP, ECG, Cr, inpatient PCI, H-FABP, cTnI3c, e, f
Kim 200613,ACohortKorea215246565.18ACSDeath, NF_CVD HFAdmissionAge, sex, NT-proBNP, cTnI, HBP, DM, smoke, HC, LVEF, diagnosis2c, d
Lindahl 200014RCTSweden9171247065.337Unstable CHDDeath24 hAge, sex, BMI, smoke, HBP, previous AMI, history of HF, DM, stable angina, stroke, number of drugs taking at admission, ECG, the index diagnosis, cTnT, fibrinogen level1c
Nikfardjam 200015CohortAustria729118617536AMIF_CVDAdmissionAge, smoke, treatment, time from onset to admission, Cr kinase, DM, HC, HBP3c, d, e
Oldgren 200316RCTSweden3202266.51UA, AMIDeath, MI<24 h6a, b, c, d, e, f
Ray 200717,BRCTAmerica220056762.269.06NSTE-ACSDeath, NF_MI41 hAge, sex, DM, smoke, HBP, MI, ECG, NSTEMI, prior revascularisation, medication, treatment2a, c
Sanchis 200418,ACohortSpain6654566746AMIDeath48 h after admissionAge, Killip class, HP, smoke, DM, previous ischaemic heart disease, ejection fraction4a, b, c, d
Scirica 200719RCTAmerica199218561.112.810ACSDeath, NF_CVD40 hAge, sex, BMI, DM, HC, MI, PAD, smoke, KC, treatment4a, c, d, f
Soeki 200220,ACohortJapan92106677.250MIDeath, NF_CVDAdmission5a, c, d, e, f
Suleiman 200621CohortIsrael10441946172.323AMIDeath, HF12–24 hAge, sex, Cr, HF, HBP, DM, smoke, MI, KC, HR, treatment, LVEF0
Toss 199722RCTSweden96513870655Unstable CHD, MIDeath, MI<72 h3c, e, f
Wollert 200723,BRCTGermany20811436663.212NSTE-ACSDeath<24 hAge, sex, delay time, smoke, HBP, HC, DM, angina, MI, ECG revascularisation, HF3a, d, f
Zairis 200224CohortGreece319526073.722STEMIF_CHD4.4 hAge, sex, DM, time from onset to treatment, STEMI, complete ST resolution, TIMI, LVEF2b, d
  • * The number of quality problems according to the six criteria, including sampling, study attrition, prognostic factor measurement, outcome measurement, confounding measurement and account, and analysis.25 aNo clear inclusion or exclusion criteria, or the settings of sampling were not described adequately; bno adequate collection or reporting of the information of participants who dropped out of the study; cno clear description or no blind operation of CRP measurement; dno clear definition of the outcome of interest or the outcome measurements were not valid and reliable; eno clear definition of the confounders or no (not all) important confounders were adjusted for; finsufficient data presentation or no appropriate strategy for model building.

  • The median time from onset of symptoms to collection of blood samples.

  • The mean time from onset of symptoms to administration of drugs. Blood samples for CRP measurements were obtained on admission and before the administration of any drugs.

  • § Three kinds of studies were included in this meta-analysis: Astudies investigating the prognostic value of CRP by unit CRP; Bby a unit change of natural logarithmically transformed CRP, and otherwise, by CRP categories.

  • Articles were secondary-analyses of randomised controlled trials.

  • ACS, acute coronary syndrome; AMI, acute myocardial infarction; BMI, body mass index; BP, blood pressure; CABG, coronary artery bypass grafting; CHD, coronary heart disease; CK-MB, creatine phosphokinase isoenzyme MB; Cr, creatinine; CRP, C-reactive protein; cTnI, cardiac troponin I; cTnT, cardiac troponin T; CVD, cardiovascular disease; DM, diabetes mellitus; ECG, electrocardiogram; F_MI, F_CHD and F_CVD, fatal MI, CHD and CVD; HBP, high blood pressure; HC, hypercholesterolaemia; HF, heart failure; H-FABP, heart fatty acid-binding protein; HR, heart rate; KC, Killip class; LVEF, left ventricular ejection fraction; MI, myocardial infarction; NF_CHD, NF_CVD and NF_MI, non-fatal CHD, CVD and MI; NSTE-ACS, non–ST Elevation ACS; NT-proBNP, N-terminal pro-brain natriuretic peptide; PAD, peripheral arterial disease; PCI, percutaneous coronary intervention; RCT, randomised controlled trial; STEMI, ST-segment elevation myocardial infarction; TIMI, thrombolysis in myocardial infarction; tHcy, total homocysteine; UA, unstable angina.