Table 2

Subgroup analysis of N-acetylcysteine (NAC) trials

CharacteristicStratumN/nOR95% CII2
Diabetic statusDiabetic1/870.750.21 to 2.67n/a
Non-diabetic26/56070.770.65 to 0.9139
InterventionCAG14/39960.800.65 to 0.9950
CAG/PCI13/16980.720.55 to 0.9316
Contrast dose*<125 mL13/43000.890.74 to 1.0813
>125 mL13/13440.450.32 to 0.6428
Renal function*sCr ≥1.111/16400.760.57 to 1.020
sCr ≥1.413/9800.460.32 to 0.6546
NAC dose*<2400 mg6/12140.740.54 to 1.0053
=2400 mg13/13490.690.49 to 0.9832
>2400 mg7/30710.870.68 to 1.1131
NAC routeOral23/47010.770.64 to 0.9434
Intravenous4/9930.750.54 to 1.0460
Date1999–200820/23960.620.48 to 0.8041
2009–present7/32980.920.73 to 1.130
Risk of biasLow risk10/39750.820.67 to 1.0052
High risk17/17190.670.49 to 0.9026
  • *The sum of the trials across strata for contrast dose do not sum 27 because one trial did not report average contrast dose. Likewise for renal function, three trials did not describe baseline sCr adequately and were excluded. Likewise for NAC, dose one trial based dose on patient weight and was excluded.

  • CAG, coronary angiography; N, number of trials; PCI, percutaneous coronary intervention; n, total number of participants; sCr, serum creatinine.