The impact of unexpected intensive care unit admission after cancer surgery on long-term symptom burden among older adults: a population-based longitudinal analysis

BACKGROUND

Older adults are at high-risk for a post-operative intensive care unit (ICU) admission, yet little is known about the impact of these admissions on quality of life. The objective of this study was to evaluate the impact of an unexpected post-operative ICU admission on the burden of cancer symptoms among older adults who underwent high-intensity cancer surgery and survived to hospital discharge.

METHODS

We performed a population-based cohort study of older adults (age ≥ 70) who underwent high-intensity cancer surgery and survived to hospital discharge in Ontario, Canada (2007-2017). Using the Edmonton Symptom Assessment System (ESAS), a standardized tool that quantifies patient-reported physical, mental, and emotional symptoms, we described the burden of cancer symptoms during the year after surgery. Total symptom scores ≥ 40 indicated a moderate-to-severe symptom burden. Modified log-Poisson analysis was used to estimate the impact of an unexpected post-operative ICU admission (admission not related to routine monitoring) on the likelihood of experiencing a moderate-to-severe symptom burden during the year after surgery, accounting for potential confounders. We then used multivariable generalized linear mixed models to model symptom trajectories among patients with two or more ESAS assessments. A 10-point difference in total symptom scores was considered clinically significant.

RESULTS

Among 16,560 patients (mean age 76.5 years; 43.4% female), 1,503 (9.1%) had an unexpected ICU admission. After accounting for baseline characteristics, patients with an unexcepted ICU admission were more likely to experience a moderate-to-severe symptom burden relative to those without an unexpected ICU admission (RR 1.64, 95% CI 1.31-2.05). Specifically, among patients with an unexcepted ICU admission the average probability of experiencing moderate-to-severe symptoms ranged from 6.9% (95 CI 5.8-8.3%) during the first month after surgery to 3.2% (95% CI 0.9-11.7%) at the end of the year. Among the 11,229 (67.8%) patients with multiple ESAS assessments, adjusted differences in total scores between patients with and without an unexpected ICU admission ranged from 2.0 to 5.7-points throughout the year (p < 0.001).

CONCLUSION

While unexpected ICU admissions are associated with a small increase in the likelihood of experiencing a moderate-to-severe symptom burden, most patients do not experience a high overall symptom burden during the year after surgery. These findings support the role of aggressive therapy among older adults after major surgery.

A Population-Based Analysis of Long-Term Outcomes Among Older Adults Requiring Unexpected Intensive Care Unit Admission After Cancer Surgery

BACKGROUND

High-intensity cancer surgery is increasingly common among older adults. However, these patients are at high-risk for unexpected intensive care unit (ICU) admissions after surgery. How these admissions impact older adults' long-term outcomes is unknown.

METHODS

We performed a population-based, cohort study of older adults (age ≥ 70 years) who underwent high-intensity cancer surgery from 2007 to 2017. Analyses were performed to examine time alive and at home following surgery, defined as time from surgery to nursing home admission or death. Patients were followed for up to 5 years. Extended Cox proportional hazards models examined the independent association between unexpected ICU admission (ICU admissions excluding routine postoperative monitoring) and remaining alive and at home. Subgroup analysis stratified patients by duration of mechanical ventilation (MV).

RESULTS

Of 47,367 identified older adults, 7372 (15.6%) had an unexpected ICU admission. Patients with an unexpected ICU admission had a significantly lower probability of being alive and at home at 5 years (26.2%; 95% confidence interval [CI] 25.1-27.2%) compared with those without an unexpected admission (56.8%; 95% CI 56.3-57.4%). After adjusting for baseline characteristics, unexpected ICU admission remained associated with less time alive and at home. The elevated risk of death or nursing home admission persisted for 5 years after surgery (years 2-5: hazard ratio [HR] 1.58, 95% CI 1.50-1.66). Duration of MV was inversely associated with time alive and at home.

CONCLUSIONS

Older adults with an unexpected ICU admission after high-intensity cancer surgery are at increased risk for death or admission to a nursing home for at least 5 years.