Stratum-specific medians and median differences in myocardial salvage index between RIC and control groups according to cardiovascular risk factors, lipid and glucose levels, and medication use
| RIC+pPCI | pPCI | |||||
|---|---|---|---|---|---|---|
| N* | Myocardial salvage index Median (95% CI) | N | Myocardial salvage index Median (95% CI) | Median difference (95% CI)† | p-Value for interaction | |
| Overall population | 71 | 0.75 (0.64 to 0.86) | 68 | 0.56 (0.42 to 0.70) | 0.19 (0.01 to 0.37) | 0.03 |
| Cardiovascular risk factors | ||||||
| Age (years) | ||||||
| ≥70 | 23 | 0.67 (0.43 to 0.91) | 21 | 0.53 (0.38 to 0.68) | 0.14 (−0.14 to 0.42) | 0.87 |
| <70 | 48 | 0.76 (0.66 to 0.86) | 47 | 0.65 (0.46 to 0.84) | 0.11 (−0.11 to 0.33) | |
| Gender | ||||||
| Female | 14 | 0.93 (0.70 to 1.00) | 13 | 0.60 (0.37 to 0.83) | 0.33 (0.01 to 0.65) | 0.56 |
| Male | 57 | 0.74 (0.56 to 0.92) | 55 | 0.53 (0.38 to 0.68) | 0.21 (−0.03 to 0.45) | |
| Smoking status | ||||||
| Smoker | 34 | 0.63 (0.44 to 0.82) | 38 | 0.65 (0.42 to 0.88) | −0.02 (−0.32 to 0.28) | 0.13 |
| Non-smoker | 37 | 0.80 (0.68 to 0.92) | 29 | 0.55 (0.42 to 0.68) | 0.25 (0.08 to 0.42) | |
| Body mass index (kg/m2) | ||||||
| ≥25 | 44 | 0.73 (0.56 to 0.90) | 41 | 0.53 (0.37 to 0.69) | 0.20 (−0.03 to 0.43) | 1.00 |
| <25 | 27 | 0.75 (0.60 to 0.90) | 25 | 0.55 (0.34 to 0.76) | 0.20 (−0.06 to 0.46) | |
| Diabetes mellitus | ||||||
| Yes | 6 | 0.80 (0.62 to 0.98) | 8 | 0.60 (0.36 to 0.84) | 0.20 (−0.10 to 0.50) | 0.92 |
| No | 65 | 0.74 (0.61 to 0.87) | 60 | 0.56 (0.40 to 0.72) | 0.18 (−0.02 to 0.38) | |
| Hypertension | ||||||
| Yes | 32 | 0.76 (0.65 to 0.87) | 19 | 0.60 (0.37 to 0.83) | 0.16 (−0.10 to 0.42) | 0.84 |
| No | 39 | 0.67 (0.45 to 0.89) | 49 | 0.55 (0.40 to 0.70) | 0.12 (−0.15 to 0.39) | |
| Left ventricular hypertrophy | ||||||
| Yes | 7 | 0.50 (0.30 to 0.70) | 8 | 0.48 (0.23 to 0.73) | 0.02 (−0.30 to 0.34) | 0.35 |
| No | 36 | 0.76 (0.62 to 0.90) | 39 | 0.55 (0.37 to 0.73) | 0.21 (−0.02 to 0.44) | |
| Lipid and glucose levels | ||||||
| Total cholesterol (mmol/L) | ||||||
| ≥5.0 | 27 | 0.78 (0.68 to 0.88) | 22 | 0.55 (0.35 to 0.75) | 0.23 (0.00 to 0.46) | 0.86 |
| <5.0 | 34 | 0.76 (0.57 to 0.95) | 35 | 0.50 (0.33 to 0.67) | 0.26 (0.01 to 0.51) | |
| LDL cholesterol (mmol/L) | ||||||
| ≥3.0 | 30 | 0.78 (0.67 to 0.89) | 29 | 0.55 (0.40 to 0.70) | 0.23 (0.05 to 0.41) | 0.72 |
| <3.0 | 29 | 0.79 (0.63 to 0.95) | 28 | 0.50 (0.28 to 0.72) | 0.29 (0.02 to 0.56) | |
| Plasma glucose (mmol/L) | ||||||
| ≥11.1 | 6 | 0.73 (0.44 to 1.00) | 7 | 0.48 (0.29 to 0.67) | 0.25 (−0.09 to 0.59) | 0.25 |
| <11.1 | 46 | 0.67 (0.50 to 0.84) | 45 | 0.68 (0.51 to 0.85) | 0.01 (−0.23 to 0.25) | |
| HbA1c (%) | ||||||
| ≥6.5 | 6 | 0.80 (0.60 to 1.00) | 5 | 0.48 (0.12 to 0.84) | 0.32 (−0.09 to 0.73) | 0.73 |
| <6.5 | 46 | 0.77 (0.65 to 0.89) | 43 | 0.53 (0.39 to 0.67) | 0.24 (0.06 to 0.42) | |
| Medication use | ||||||
| β-blockers | ||||||
| Yes | 11 | 0.87 (0.68 to 1.00) | 10 | 0.60 (0.34 to 0.86) | 0.27 (−0.05 to 0.59) | 0.61 |
| No | 58 | 0.70 (0.56 to 0.84) | 57 | 0.53 (0.38 to 0.68) | 0.17 (−0.03 to 0.37) | |
| ACE inhibitors | ||||||
| Yes | 14 | 0.75 (0.63 to 0.87) | 6 | 0.48 (0.13 to 0.83) | 0.27 (−0.10 to 0.64) | 0.69 |
| No | 55 | 0.73 (0.55 to 0.91) | 61 | 0.55 (0.41 to 0.69) | 0.18 (−0.05 to 0.41) | |
| ARBs | ||||||
| Yes | 10 | 0.58 (0.41 to 0.75) | 5 | 0.48 (0.24 to 0.72) | 0.10 (−0.19 to 0.39) | 0.55 |
| No | 59 | 0.78 (0.67 to 0.89) | 62 | 0.56 (0.42 to 0.70) | 0.22 (0.04 to 0.40) | |
| Calcium channel blockers | ||||||
| Yes | 7 | 0.70 (0.42 to 0.98) | 8 | 0.40 (0.00 to 0.84) | 0.30 (−0.21 to 0.81) | 0.73 |
| No | 62 | 0.75 (0.60 to 0.90) | 59 | 0.55 (0.41 to 0.69) | 0.20 (0.00 to 0.40) | |
| Statins | ||||||
| Yes | 12 | 0.80 (0.60 to 1.00) | 12 | 0.46 (0.23 to 0.69) | 0.34 (0.03 to 0.65) | 0.19 |
| No | 59 | 0.74 (0.61 to 0.87) | 56 | 0.65 (0.50 to 0.80) | 0.09 (−0.11 to 0.29) | |
*N=number of patients with data available for variable and myocardial salvage index.
†Median difference=calculated median difference in myocardial salvage index between RIC and control groups using non-parametric quantile regression. CIs and p values for interaction are computed with non-parametric bootstrapping (1000 replications).
ARBs, angiotensin II receptor blockers; HbA1c, glycated haemoglobin; LDL, low-density lipoprotein; pPCI, primary percutaneous coronary intervention; RIC, remote ischaemic conditioning.