Weekly distribution of the onset of acute myocardial infarction in patient subgroups, categorised by sociodemographic variables, medical history, habits, and infarct characteristics
| Odds ratios (95% confidence interval) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Sunday | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Total (n) | |
| Age adjusted Mantel-Haenszel odds ratios: observed v expected number of cases per day of week. | ||||||||
| *p = 0.037; †p = 0.038. | ||||||||
| ‡Total number of patients with coronary angiogram was 2146. | ||||||||
| MI, myocardial infarction. | ||||||||
| All subjects | 0.92 (0.78 to 1.08) | 1.09 (0.93 to 1.28) | 0.98 (0.83 to 1.15) | 0.98 (0.83 to 1.15) | 1.02 (0.87 to 1.20) | 1.00 (0.85 to 1.17) | 0.99 (0.85 to 1.17) | 2400 |
| Sociodemographic variables | ||||||||
| Men | 0.95 (0.78 to 1.14) | 1.11 (0.93 to 1.34) | 0.99 (0.82 to 1.20) | 0.99 (0.82 to 1.19) | 1.03 (0.86 to 1.24) | 1.08 (0.90 to 1.30) | 0.88 (0.73 to 1.07) | 1796 |
| Women | 0.87 (0.62 to 1.21) | 1.06 (0.77 to 1.45) | 0.96 (0.69 to 1.33) | 0.99 (0.71 to 1.36) | 1.01 (0.74 to 1.40) | 0.79 (0.56 to 1.11) | 1.39* (1.02 to 1.88) | 604 |
| Age (years) | ||||||||
| ≥65 | 0.94 (0.75 to 1.18) | 1.09 (0.88 to 1.36) | 0.89 (0.71 to 1.12) | 1.09 (0.88 to 1.36) | 0.97 (0.78 to 1.22) | 1.00 (0.80 to 1.25) | 0.98 (0.78 to 1.23) | 1248 |
| <65 | 0.90 (0.71 to 1.14) | 1.09 (0.86 to 1.37) | 1.07 (0.85 to 1.35) | 0.86 (0.68 to 1.10) | 1.07 (0.85 to 1.35) | 0.99 (0.79 to 1.25) | 1.01 (0.80 to 1.27) | 1152 |
| Working | 0.89 (0.71 to 1.12) | 1.26† (1.01 to 1.56) | 1.03 (0.82 to 1.28) | 0.92 (0.73 to 1.15) | 1.05 (0.84 to 1.31) | 0.97 (0.78 to 1.22) | 0.87 (0.69 to 1.09) | 1247 |
| Non-working | 0.95 (0.74 to 1.22) | 0.95 (0.74 to 1.22) | 0.98 (0.76 to 1.25) | 1.03 (0.81 to 1.32) | 1.00 (0.78 to 1.28) | 1.00 (0.78 to 1.28) | 1.10 (0.87 to 1.41) | 1038 |
| Habits | ||||||||
| Current smoker | 0.88 (0.69 to 1.10) | 1.07 (0.85 to 1.34) | 1.08 (0.87 to 1.35) | 1.05 (0.84 to 1.31) | 0.99 (0.79 to 1.25) | 1.03 (0.82 to 1.29) | 0.92 (0.73 to 1.16) | 1226 |
| Not current smoker | 0.94 (0.73 to 1.20) | 1.14 (0.89 to 1.44) | 0.90 (0.70 to 1.56) | 0.87 (0.68 to 1.12) | 1.05 (0.82 to 1.34) | 1.01 (0.79 to 1.29) | 1.06 (0.83 to 1.34) | 1043 |
| Habitual alcohol drinker | 0.96 (0.71 to 1.31) | 1.14 (0.84 to 1.54) | 1.10 (0.81 to 1.49) | 0.89 (0.65 to 1.22) | 0.89 (0.65 to 1.22) | 1.19 (0.88 to 1.60) | 0.83 (0.61 to 1.14) | 664 |
| Not habitual alcohol drinker | 0.89 (0.72 to 1.09) | 1.09 (0.89 to 1.32) | 0.96 (0.79 to 1.18) | 1.00 (0.82 to 1.22) | 1.08 (0.89 to 1.32) | 0.95 (0.78 to 1.17) | 1.06 (0.87 to 1.30) | 1559 |
| Medical history | ||||||||
| Diabetes | 0.84 (0.63 to 1.12) | 1.07 (0.81 to 1.42) | 1.11 (0.84 to 1.46) | 1.01 (0.76 to 1.34) | 1.11 (0.84 to 1.46) | 0.96 (0.72 to 1.27) | 0.92 (0.69 to 1.22) | 791 |
| No diabetes | 0.95 (0.77 to 1.16) | 1.10 (0.90 to 1.34) | 0.91 (0.74 to 1.12) | 0.98 (0.80 to 1.20) | 0.96 (0.79 to 1.18) | 1.06 (0.87 to 1.29) | 1.02 (0.83 to 1.24) | 1534 |
| Hypertension | 1.02 (0.81 to 1.29) | 1.17 (0.94 to 1.47) | 0.83 (0.65 to 1.05) | 0.97 (0.76 to 1.22) | 0.97 (0.77 to 1.23) | 1.10 (0.88 to 1.38) | 0.96 (0.76 to 1.21) | 1156 |
| No hypertension | 0.83 (0.65 to 1.05) | 1.05 (0.83 to 1.32) | 1.15 (0.91 to 1.44) | 1.01 (0.80 to 1.27) | 1.07 (0.85 to 1.35) | 0.95 (0.75 to 1.20) | 0.97 (0.76 to 1.22) | 1149 |
| Hyperlipidaemia | 0.98 (0.75 to 1.28) | 1.05 (0.80 to 1.36) | 1.03 (0.79 to 1.34) | 0.93 (0.71 to 1.22) | 1.17 (0.90 to 1.52) | 0.88 (0.67 to 1.16) | 0.94 (0.71 to 1.23) | 878 |
| No hyperlipidaemia | 0.89 (0.71 to 1.11) | 1.11 (0.90 to 1.37) | 0.96 (0.77 to 1.19) | 1.02 (0.82 to 1.26) | 0.93 (0.75 to 1.15) | 1.10 (0.89 to 1.35) | 1.01 (0.81 to 1.25) | 1372 |
| Previous MI | 1.43 (0.94 to 2.17) | 1.03 (0.66 to 1.59) | 1.10 (0.71 to 1.70) | 0.76 (0.47 to 1.20) | 0.98 (0.63 to 1.52) | 0.78 (0.49 to 1.24) | 0.90 (0.57 to 1.41) | 317 |
| No previous MI | 0.83 (0.69 to 1.00) | 1.09 (0.92 to 1.31) | 0.98 (0.81 to 1.17) | 1.00 (0.84 to 1.20) | 1.04 (0.87 to 1.25) | 1.06 (0.89 to 1.27) | 1.00 (0.84 to 1.20) | 1934 |
| Previous angina | 0.91 (0.66 to 1.25) | 1.01 (0.74 to 1.39) | 0.87 (0.63 to 1.21) | 1.05 (0.77 to 1.44) | 1.09 (0.80 to 1.49) | 1.14 (0.84 to 1.56) | 0.95 (0.69 to 1.30) | 638 |
| No previous angina | 0.90 (0.74 to 1.11) | 1.15 (0.95 to 1.40) | 1.05 (0.86 to 1.28) | 0.970 (0.79 to 1.18) | 1.01 (0.82 to 1.23) | 0.99 (0.81 to 1.20) | 0.97 (0.79 to 1.18) | 1594 |
| Infarct characteristics | ||||||||
| Q wave infarct | 0.93 (0.76 to 1.12) | 1.11 (0.92 to 1.34) | 0.97 (0.80 to 1.17) | 1.01 (0.83 to 1.22) | 1.05 (0.87 to 1.27) | 0.94 (0.77 to 1.14) | 1.02 (0.85 to 1.24) | 1726 |
| Non-Q wave infarction | 0.93 (0.66 to 1.30) | 1.15 (0.83 to 1.59) | 0.99 (0.71 to 1.38) | 0.83 (0.59 to 1.17) | 0.99 (0.70 to 1.38) | 1.23 (0.89 to 1.69) | 0.91 (0.65 to 1.28) | 560 |
| Anterior infarct | 0.93 (0.74 to 1.18) | 1.04 (0.83 to 1.31) | 0.95 (0.75 to 1.20) | 0.99 (0.79 to 1.25) | 1.04 (0.82 to 1.30) | 1.01 (0.81 to 1.28) | 1.04 (0.82 to 1.30) | 1169 |
| Not anterior infarct | 0.86 (0.67 to 1.10) | 1.15 (0.91 to 1.45) | 1.04 (0.82 to 1.32) | 1.00 (0.79 to 1.27) | 0.99 (0.78 to 1.26) | 1.01 (0.79 to 1.28) | 0.92 (0.72 to 1.17) | 1086 |
| Multivessel disease‡ | 0.99 (0.94 to 1.35) | 1.12 (0.82 to 1.52) | 1.10 (0.81 to 1.50) | 0.98 (0.71 to 1.33) | 0.94 (0.68 to 1.29) | 0.94 (0.68 to 1.29) | 0.91 (0.66 to 1.25) | 641 |
| Single vessel disease‡ | 0.84 (0.68 to 1.04) | 1.07 (0.87 to 1.31) | 0.97 (0.79 to 1.19) | 1.04 (0.85 to 1.27) | 1.09 (0.89 to 1.34) | 1.03 (0.84 to 1.27) | 1.01 (0.82 to 1.23) | 1505 |