Background
Methods
Data source and study population
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Any ICD-10-AM diagnosis codes for cancer (see Additional file 2: Appendix 2)
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Any ICD-10-AM diagnosis codes or any ICD-10-AM procedure codes for immunocompromised state (see Additional file 2: Appendix 2)
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Major Diagnostic Categories 14 (pregnancy, childbirth and puerperium)
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A stay in hospital of less than 4 days
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Missing data on discharge status, sex, age, year or principal diagnosis (There were no missing values for these variables among the elective surgical admissions aged ≥18 years included in our study.)
Patient demographic and hospital characteristics
Study outcomes
Statistical analysis
Results
Characteristics | Non-sepsis | Sepsis | IR of sepsis |
---|---|---|---|
Total | 142,646 | 1857 | 12.9 |
Year of admission | |||
2007 | 23,564 (16.5%) | 281 (15.1%) | 11.8 |
2008 | 23,993 (16.8%) | 293 (15.8%) | 12.1 |
2009 | 23,305 (16.3%) | 280 (15.1%) | 11.9 |
2010 | 24,447 (17.1%) | 324 (17.5%) | 13.1 |
2011 | 24,195 (17.0%) | 315 (17.0%) | 12.9 |
2012 | 23,142 (16.2%) | 364 (19.6%) | 15.5 |
Hospitalisation in preceding year | |||
2007 | N/A | N/A | |
2008 | 2275/23,993 (9.5%) | 35/293 (12.0%) | |
2009 | 2734/23,305 (11.7%) | 40/280 (14.3%) | |
2010 | 3344/24,447 (13.7%) | 46/324 (14.2%) | |
2011 | 3771/24,195 (15.6%) | 54/315 (17.1%) | |
2012 | 3889/23,142 (16.8%) | 64/364 (17.6%) | |
Age | |||
≥18 years to <35 years | 8838 (6.2%) | 106 (5.7%) | 11.9 |
≥35 years to <55 years | 28,015 (19.6%) | 348 (18.7%) | 12.3 |
≥55 years to <75 years | 64,382 (45.1%) | 814 (43.8%) | 12.5 |
≥75 years | 41,411 (29.0%) | 589 (31.7%)* | 14 |
Mean ± SD | 63.8 ± 16.3 | 64.8 ± 16.3** | |
Sex | |||
Male | 67,011 (47.0%) | 1147 (61.8%)** | 16.8 |
Female | 75,635 (53.0%) | 710 (38.2%)** | 9.3 |
Country of birth | |||
Australia and New Zealand | 98,787 (69.3%) | 1249 (67.3%) | 12.5 |
United Kingdom, United States and Canada | 10,205 (7.2%) | 111 (6.0%)* | 10.8 |
Non-English-speaking Europe | 15,949 (11.2%) | 220 (11.8%) | 13.6 |
North Africa | 5564 (3.9%) | 78 (4.2%) | 13.8 |
Asia | 6,922 (4.9%) | 93 (5.0%) | 13.3 |
Others | 4,222 (3.0%) | 77 (4.1%)** | 17.9 |
Unknown | 997 (0.7%) | 29 (1.6%)** | 28.3 |
Marital status | |||
Married | 77,810 (54.6%) | 1005 (54.1%) | 12.8 |
Single | 62,745 (44.0%) | 805 (43.3%) | 12.7 |
Unknown | 1923 (1.3%) | 47 (2.5%)** | 23.9 |
Severity of illness/co-morbidity | |||
Normal | 116,031 (81.3%) | 969 (52.2%)** | 8.3 |
Moderate | 16,509 (11.6%) | 322 (17.3%)** | 19.1 |
Severe | 5700 (4.0%) | 213 (11.5%)** | 36.0 |
Very severe | 4406 (3.1%) | 353 (19.0%)** | 74.2 |
SEIFA scores | |||
First quartile (most disadvantaged) | 48,634 (34.1%) | 590 (31.8%)* | 12 |
Second quartile | 41,195 (28.9%) | 568 (30.6%) | 13.6 |
Third quartile | 31,862 (22.3%) | 408 (22.0%) | 12.6 |
Fourth quartile (most advantaged) | 19,888 (13.9%) | 267 (14.4%) | 13.2 |
Unknown | 1067 (0.7%) | 24 (1.3%)** | 22 |
Local health district of facilities | |||
Metropolitan | 91,018 (63.8%) | 1336 (71.9%)** | 14.5 |
Rural | 44,902 (31.5%) | 420 (22.6%)** | 9.3 |
Unknown | 6726 (4.7%) | 101 (5.4%) | 14.8 |
Peer hospital group | |||
Principal referral | 85,108 (59.7%) | 1358 (73.1%)** | 15.7 |
Ungrouped acute | 2418 (1.7%) | 6 (0.3%)** | 2.5 |
Major metropolitan and non-metropolitan | 44,850 (31.4%) | 444 (23.9%)** | 9.8 |
District groups 1 and 2 | 10,270 (7.2%) | 49 (2.6%)** | 4.7 |
Major surgical procedure | |||
CABG | 8994 (6.3%) | 186 (10.0%)** | 20.3 |
Abdominal surgery | 33,506 (23.5%) | 649 (35.0%)** | 19.0 |
EVAR | 1458 (1.0%) | 20 (1.1%) | 13.5 |
Total hip replacement | 13,632 (9.6%) | 45 (2.4%)** | 3.3 |
Total knee replacement | 22,598 (15.8%) | 57 (3.1%)** | 2.5 |
Other | 62,458 (43.8%) | 900 (48.5%)** | 14.2 |
Length of stay | |||
Mean ± SD | 9.1 ± 9.6 | 33.4 ± 31.6 | |
Median (IQR) | 6 (5–10) | 24 (14–42) |
Mortality at 30 days, 60 days, 90 days and 1 year post-discharge
Days after discharge | Mortality, % | HR (95% CI) | |||
---|---|---|---|---|---|
Non-sepsis (n = 142,646) | Sepsis (n = 1857) |
P value | Unadjusted | Adjusted | |
30 days | 0.7 | 4.6 | <0.001 | 6.64 (5.23–8.44) | 2.75 (2.14–3.53) |
60 days | 1.2 | 6.7 | <0.001 | 5.90 (4.67–7.45) | 2.45 (1.94–3.10) |
90 days | 1.5 | 8.1 | <0.001 | 5.52 (4.40–6.91) | 2.31 (1.85–2.87) |
1 year | 3.8 | 13.5 | <0.001 | 3.79 (3.25–4.42) | 1.71 (1.46–2.00) |
Multivariate analysis of 1-year mortality and its trends
Characteristics | Non-sepsis (n = 142,646) | Sepsis (n = 1857) | ||
---|---|---|---|---|
Mortality, % | HR (95% CI) | Mortality, % | HR (95% CI) | |
Year of admission†
| ||||
2007 | 4.1 | 1.00 | 16.7 | 1.00 |
2008 | 4.1 | 1.03 (0.95–1.12) | 10.9 | 0.70 (0.43–1.14) |
2009 | 3.9 | 1.03 (0.94–1.12) | 11.8 | 0.76 (0.48–1.21) |
2010 | 3.7 | 1.05 (0.92–1.19) | 16.1 | 1.04 (0.76–1.43) |
2011 | 3.7 | 1.05 (0.96–1.15) | 14 | 0.88 (0.60–1.31) |
2012 | 3.5 | 0.98 (0.89–1.09) | 11.8 | 0.78 (0.48–1.28) |
Age groups | ||||
≥18 years to <35 years | 0.5 | 1.00 | 6.6 | 1.00 |
≥35 years to <55 years | 0.9 | 1.99** (1.35–2.93) | 7.5 | 1.10 (0.40–3.04) |
≥55 years to <75 years | 2.1 | 5.46** (3.77–7.92) | 10.8 | 1.60 (0.76–3.38) |
≥75 years | 9.2 | 20.0** (13.5–29.6) | 22.1 | 3.50** (1.56–7.87) |
Sex | ||||
Male | 4.3 | 1.00 | 13.4 | 1.00 |
Female | 3.4 | 0.76** (0.71–0.82) | 13.7 | 1.05 (0.81–1.37) |
Country of birth | ||||
Australia and New Zealand | 4.1 | 1.00 | 13.9 | 1.00 |
United Kingdom, United States and Canada | 4.4 | 0.96 (0.88–1.05) | 11.7 | 0.66 (0.36–1.19) |
Non-English-speaking Europe | 4.1 | 0.83** (0.74–0.93) | 17.3 | 0.97 (0.69–1.36) |
North Africa | 1.5 | 0.50** (0.44–0.58) | 7.7 | 0.52 (0.18–1.53) |
Asia | 1.9 | 0.68** (0.54–0.85) | 10.8 | 0.80 (0.37–1.72) |
Others | 1.7 | 0.66** (0.53–0.83) | 6.5 | 0.47 (0.18–1.21) |
Unknown | 5.6 | 1.02 (0.81–1.28) | 17.2 | 1.45 (0.76–2.78) |
Marital status | ||||
Married | 2.9 | 1.00 | 12.4 | 1.00 |
Single | 4.8 | 1.37** (1.28–1.46) | 14.9 | 1.10 (0.89–1.36) |
Unknown | 6.4 | 1.67** (1.37–2.03) | 12.8 | 0.93 (0.39–2.24) |
Severity of illness/co-morbidity | ||||
Normal | 2.5 | 1.00 | 9.2 | 1.00 |
Moderate | 7.5 | 2.04** (1.88–2.21) | 9.9 | 0.96 (0.61–1.50) |
Severe | 10.1 | 2.34** (2.01–2.72) | 20.2 | 2.05** (1.45–2.89) |
Very severe | 15.5 | 3.34** (2.99–3.72) | 24.6 | 2.17** (1.49–3.17) |
SEIFA quartiles | ||||
First quartile (most disadvantaged) | 4.0 | 1.00 | 14.9 | 1.00 |
Second quartile | 3.7 | 0.93 (0.85–1.00) | 13.2 | 0.91 (0.65–1.26) |
Third quartile | 3.5 | 0.94 (0.83–1.06) | 11.8 | 0.71* (0.52–0.97) |
Fourth quartile (most advantaged) | 4.3 | 0.99 (0.80–1.23) | 13.1 | 0.68 (0.35–1.32) |
Unknown | 2.4 | 0.64* (0.41–1.00) | 20.8 | 1.59 (0.90–2.84) |
Local health district of facility | ||||
Metropolitan | 3.7 | 1.00 | 13.8 | 1.00 |
Rural and regional NSW | 4.3 | 1.06 (0.88–1.27) | 12.6 | 0.81 (0.60–1.10) |
Others | 3.1 | 0.72** (0.64–0.81) | 12.9 | 1.08 (0.70–1.67) |
Peer hospital group | ||||
Principal referral group | 3.9 | 1.00 | 12.4 | 1.00 |
Ungrouped acute | 2.2 | 0.59** (0.44–0.80) | 0 | – |
Major metropolitan and non-metropolitan | 4 | 1.20 (1.00–1.45) | 17.1 | 1.53* (1.10–2.11) |
District groups 1 and 2 | 2.7 | 1.10 (0.85–1.44) | 12.2 | 1.04 (0.40–2.73) |
Major surgical procedure | ||||
CABG | 2.0 | 1.00 | 7.0 | 1.00 |
Abdominal surgery | 2.8 | 1.91** (1.50–2.43) | 8.3 | 1.25 (0.61–2.56) |
EVAR | 7.3 | 2.40** (1.92–3.00) | 25.0 | 3.79** (1.39–10.3) |
Total hip replacement | 1.5 | 0.80 (0.62–1.03) | 11.1 | 1.51 (0.47–4.78) |
Total knee replacement | 0.8 | 0.46** (0.36–0.59) | 5.3 | 0.68 (0.19–2.42) |
Other | 6.1 | 3.13** (2.50–3.91) | 19.0 | 2.69** (1.38–5.22) |
Length of stay | 1.01** (1.01–1.01) | 1.00** (1.00–1.01) |