Sex-specific differences in alive hospital discharge following infrarenal abdominal aortic aneurysm repair

Abstract

Background and aims: A longer time to alive hospital discharge following infrarenal abdominal aortic aneurysm (AAA) repair is associated with reduced patient satisfaction and increased length of stay, hospital-acquired deconditioning, infection, and costs. This study investigated sex-specific differences in, and drivers of, the rate of alive hospital discharge.

Methods: Examination of UK National Vascular Registry (UK NVR), 2014-19, and Swedish National Patient Registry (SE NPR) elective AAA patients, 2010-18, for endovascular (EVAR) or open aneurysm repair (OAR). Cox models assessed sex-specific difference in the rate of alive hospital discharge, adjusting for co-morbidity, anatomy, standard of care, post-operative complications, and year, with in-hospital death as the competing risk.

Results: A total of 29 751 AAA repairs (UK NVR: EVAR 12 518:1532; OAR 6803:837; SE NPR: EVAR 4234:792; OAR 2638:497, men:women) were assessed. For EVAR, the unadjusted rate of alive hospital discharge was ∼25% lower for women [UK NVR: hazard ratio (HR) 0.75 (0.71-0.80), P < .001; SE NPR: HR 0.75 (0.69-0.81), P < .001]. Following adjustment, the sex-specific HR narrowed but remained significant [UK NVR: HR 0.83 (0.79-0.88), P < .001; SE NPR: HR 0.83 (0.76-0.89), P < .001]. For OAR, the rate of alive hospital discharge was 23%-27% lower for women [UK NVR: HR 0.73 (0.67-0.78), P < .001; SE NPR: HR 0.77 (0.70-0.85), P < .001]. Following adjustment, the sex-specific HR narrowed [UK NVR: HR 0.82 (0.76-0.88), P < .001; SE NPR: HR 0.79 (0.72-0.88), P < .001] but remained significant.

Conclusions: Women have a 25% lower rate of alive discharge after aortic surgery, despite adjustment for pre/peri- and post-operative parameters. Efforts to increase the rate of alive hospital discharge for women should be sought.

Keywords: Abdominal aortic aneurysm; Length of stay; Sex.

Structured Graphical Abstract

Structured graphical abstract demonstratating a lower rate of alive hospital discharge for women following elective abdominal aortic aneurysm repair in both the United Kingdom and Sweden.

Figure 1

Length of hospital stay in days, stratified by year, patient sex, and repair type for (A) UK NVR EVAR, (B) SE NPR EVAR, (C) UK NVR OAR and (D) SE NPR OAR. Box plots displaying median, interquartile range, and 95% confidence interval, diamonds represent mean length of stay. EVAR, endovascular aneurysm repair; UK NVR, United Kingdom National Vascular Registry; OAR, open aortic repair; Sweden NPR, Sweden National Patient Registry

Figure 2

Cumulative incidence of alive hospital discharge for men and women with in-hospital death as a competing risk for (A) open aortic repair and (B) endovascular aneurysm repair in the UK and Sweden. EVAR, endovascular aneurysm repair; NPR, National Patient Registry; NVR, National Vascular Registry; OAR, open aortic repair; SE, Sweden; UK, United Kingdom

Figure 3

Sex-specific hazard ratio for the rate of alive hospital discharge following endovascular aneurysm repair in the (A) the UK National Vascular Registry and (B) Sweden National Patient Registry and following OAR in the (C) the UK National Vascular Registry and (D) Sweden National Patient Registry. A hazard of <1 indicates a lower rate of alive discharge from hospital, and horizontal lines represent 95% confidence interval of the estimated effect. UK National Vascular Registry: co-morbidities—ischaemic heart disease, congestive heart failure, abnormal electrocardiogram, chronic obstructive pulmonary disease, diabetes, chronic renal disease, stroke, cancer*, peripheral arterial disease*, anaemia, hypoalbuminaemia, body mass index, American Society of Anaesthesiology grade ≥3; anatomical factors—aortic size index, neck angle*, neck diameter*, symptomatic aneurysm; standard of care—waiting time, pre-operative assessment, cardiovascular risk prevention, peri-operative medications; year (reference level—2014); post-operative complications—return to theatre, cardiac complication, respiratory complication, stroke, renal injury, paraplegia, bowel ischaemia, major haemorrhage, limb ischaemia, major gastrointestinal complication**. Sweden National Patient Registry: co-morbidities—ischaemic heart disease, congestive heart failure, cardiac intervention, chest pain, abnormal electrocardiogram, chronic obstructive pulmonary disease, hypertension, hyperlipidaemia, diabetes, chronic renal disease, stroke, haemorrhagic stroke, peripheral arterial disease, anaemia, gastrointestinal disease, neurological disease, hypothyroidism, rheumatological disease, arthrosis, fractured neck of femur, osteoporosis, depression, anxiety, alcoholism, substance abuse, number of in-patient episodes in 1 year, number of outpatient episodes in 1 year; municipality—municipality (reference level: C), admission from (reference level: home); anatomical factors—urgent intact repair; medications review—pre-operative, post-operative; year (reference level—2010); post-operative complications—return to theatre, cardiac complication, respiratory complication, stroke, renal injury, paraplegia, bowel ischaemia**, major haemorrhage, transfusion, limb ischaemia, vessel injury, major gastrointestinal complication, surgical site infection, pulmonary embolism, post-operative confusion. EVAR, endovascular aortic repair; OAR, open aortic repair; SE NPR, Sweden National Patient Registry; UK NVR, United Kingdom National Vascular Registry. *EVAR only. **OAR only

Figure 4

Risk-adjusted hazard ratios for the rate of alive hospital discharge for women compared to men following abdominal aortic aneurysm repair for (A) EVAR and (B) OAR. A hazard of <1 indicates a lower rate of alive discharge from hospital, and horizontal lines represent 95% confidence interval of the estimated effect. CI, confidence interval; EVAR, endovascular aneurysm repair; AAA, abdominal aortic aneurysm; OAR, open aortic repair; SE, standard error; SE NPR, Sweden National Patient Register; UK NVR, United Kingdom National Vascular Registry

Figure 5

Estimated hazard rations of ‘optimal Cox models for time to alive hospital discharge following endovascular aneurysm repair in the (A) UK National Vascular Registry and (B) Sweden National Patient Registry. A hazard ratio of <1 represents a lower rate of alive discharge from hospital. Horizontal lines represent the 95% confidence intervals of estimated effects. *Indicates a peri/post-operative event. ASA, American Society of Anaesthesiology; COPD, chronic obstructive pulmonary disease; ECG, electrocardiogram; EVAR, endovascular aneurysm repair; From, location prior to admission (reference level: home); NOS, not otherwise specified; SOC, standard of care; SE, Sweden; UK, United Kingdom; Year of procedure (reference level: SE 2010/UK 2014)

Figure 6

Estimated hazard rations of ‘optimal Cox models for time to alive hospital discharge following open aortic repair in the (A) UK National Vascular Registry and (B) Sweden National Patient Registry. A hazard ratio of <1 represents a lower rate of alive discharge from hospital. Horizontal lines represent the 95% confidence intervals of estimated effects. *Indicates a peri/post-operative event. ASA, American Society of Anaesthesiology; COPD, chronic obstructive pulmonary disease; ECG, electrocardiogram; From, location prior to admission (reference level: home); OAR, open aortic repair; SOC, standard of care; SW, Sweden; UK, United Kingdom; Year of procedure (reference level: SE 2010/UK 2014)