Variable Odds ratios (95% CIs)
Age band (years)
18-39 (reference) 1 (reference)
40-49 2.118 (1.605 to 2.795)
50-59 2.375 (1.837 to 3.071)
60-69 2.193 (1.693 to 2.840)
70-79 1.590 (1.200 to 2.107)
≥ 80 0.249 (0.134 to 0.464)
Sex
Female 1 (reference)
Male 1.222 (1.073 to 1.392)
Deprivation quintile Deprivation quintile
5 (least deprived) 1 (reference)
4 1.040 (0.830 to 1.304)
3 1.021 (0.822 to 1.269)
2 0.954 (0.771 to 1.180)
1 (most deprived) 0.857 (0.691 to 1.062)
Ethnicity
White 1 (reference)
South Asian 1.328 (1.071 to 1.647)
Other Asian 1.418 (1.102 to 1.824)
Black 1.279 (1.018 to 1.607)
Mixed 1.469 (0.931 to 2.317)
Other 1.258 (0.986 to 1.605)
Discharge month
March 1 (reference)
April 3.356 (2.020 to 5.574)
May 19.067 (11.502 to 31.608)
June 31.394 (18.734 to 52.609)
July 23.842 (13.927 to 40.816)
August 14.988 (8.190 to 27.428)
September 5.200 (2.764 to 9.783)
October 1.863 (1.033 to 3.362)
Charlson Comorbidity Index items*
Peripheral vascular disease 0.723 (0.524 to 0.997)
Congestive heart failure 0.498 (0.393 to 0.631)
Acute myocardial infarction 0.581 (0.444 to 0.759)
Cerebrovascular disease 1.946 (1.539 to 2.462)
Dementia 0.657 (0.294 to 1.471)
Chronic pulmonary disease 1.031 (0.894 to 1.189)
Connective tissue disease/rheumatic disease 0.636 (0.413 to 0.978)
Peptic ulcer 1.214 (0.651 to 2.262)
Mild liver disease 0.861 (0.648 to 1.144)
Moderate or severe liver disease 0.606 (0.374 to 0.980)
Diabetes without chronic complications 0.876 (0.762 to 1.005)
Diabetes with chronic complications 0.795 (0.550 to 1.150)
Paraplegia and hemiplegia 0.973 (0.778 to 1.217)
Renal disease 0.839 (0.755 to 0.933)
Primary cancer 0.495 (0.348 to 0.705)
Metastatic carcinoma 0.141 (0.055 to 0.363)
Obesity 0.923 (0.788 to 1.081)