Stratification | Adjusted HR (95% CI) | P value interaction |
Sex | ||
Female | 2.11 (1.42 to 3.12) | 0.033 |
Male | 1.27 (0.93 to 1.72) | |
Cardiovascular disease | ||
Present | 1.59 (1.18 to 2.15) | 0.128 |
Absent | 1.21 (0.82 to 1.80) | |
Heart failure | ||
Present | 2.59 (1.42 to 4.73) | 0.007 |
Absent | 1.33 (1.01 to 1.74) | |
Ischaemic heart disease | ||
Present | 1.64 (1.01 to 2.65) | 0.437 |
Absent | 1.45 (1.10 to 1.91) |
HR adjusted for presence of cardiovascular disease and the use of QT-prolonging drugs. By conducted stratified analyses according cardiovascular disease, heart failure and ischaemic heart disease, the original matching on age and sex was lost. Therefore, HRs were additionally adjusted for age and sex when we performed stratified analyses according to cardiovascular disease, heart failure and ischaemic heart disease.