Assessment of Inpatient Mortality in the Peri-Transplant Period in Elderly Allogeneic Stem Cell Transplant Recipients with Co-Existing Mental Health Illnesses

Background

Allogeneic hematopoietic stem cell transplant (alloHCT) is a potentially curative treatment for patients with hematological malignancies and nonmalignant conditions. AlloHCT involves invasive procedures, conditioning chemotherapy regimens, and prolonged isolation during hospitalization, which is physically and emotionally challenging. Transplant related mortality is higher in older individuals. Careful assessment of mortality risk before transplant is essential for optimal patient selection and informed decision-making, especially in elderly patients. Hematopoietic cell transplantation-specific comorbidity index (HCT-CI), an important prognostic scoring tool used in patients before alloHCT, includes psychiatric comorbidity as one of the scoring criteria. Patients with depression or anxiety disorders receive one point on the scoring scale, with the assumption that the two groups of patients are at an equivalent risk. However, there is literature showing decreased overall survival and worse inpatient outcomes in patients receiving alloHCT with co-morbid depression. Our primary objective was to evaluate the inpatient outcomes of elderly patients undergoing allogeneic stem cell transplant with a concurrent diagnosis of depression and patients with anxiety and adjustment disorders.

Methods:

Patients of ages ≥ 60 years, admitted with a principal procedure code of allogeneic stem cell transplant, were recruited from the 2016-2020 National Inpatient Sample. Three cohorts were created based on ICD-10 diagnostic codes for Depression and Anxiety and adjustment disorders: patients without depression and anxiety disorders, patients with depression only, and patients with anxiety and adjustment disorders only. Patients with diagnoses of other mental illnesses were excluded. The patient characteristics between the three cohorts were evaluated. Multiple Logistic Regression models were used to determine the impact of depression and anxiety disorders on inpatient mortality.

Results:

We evaluated 11655 hospital admissions with the primary procedure code for Allogeneic Stem Cell Transplant in patients aged 60 years and above. 8375 patients did not have any mental illness. 800 patients (9.5%) had a diagnosis of Depression, and 1640 patients (19.5%) had a diagnosis of Anxiety and adjustment disorders. Comparing the primary outcomes in patients with and without Depression, the length of stay was 31.3 days vs 28.2 days (p<0.01), the mean hospital charge was 558398.01 USD vs 498971.9 USD (p <0.01), and in-patient mortality was 8.1% vs 5.9% (aOR = 1.359, 95% CI 1.010-1.829, p=0.04). Utilization of mechanical ventilation was more prevalent in patients with depression (8.8 %vs 5.8 %, p <0.01). Out of different infectious complications, pneumonia was more common in patients with depression (14.4 % vs 9.8 %, p <0.01) (Table 1a).

Baseline socio-demographic characteristics that were associated with having depression included: Female gender, White race, and Medicare insurance. Patients with depression had an increased prevalence of congestive heart failure, prior stroke, Obesity with BMI >= 35, chronic kidney disease, and COPD compared to patients without depression (p<0.01).

For the primary outcomes in patients with and without anxiety and adjustment disorders, the length of stay was 29.15 days vs 28.2 days (p <0.01), the mean hospital charge was 474274.71 USD vs 498971.94 USD (p 0.612), and the in-patient mortality was 4% vs 5.9 % (aOR=0.61, 95% CI 0.45-0.83, p<0.01). Baseline socio-demographic characteristics that were prevalent in patients with anxiety and adjustment disorders were: female gender, white race, and Medicare as the most common insurance (P<0.01) (Table 1b).

Conclusion

We found that in elderly patients admitted for alloHCT, depression was independently associated with worse inpatient outcomes, while anxiety was not. Patients with depression were noted to have an increased incidence of infectious complications as compared to those without depression, possibly accounting for their increased mortality. Prognostic scoring systems like HCT-CI may need to be modified to assign more weight to depression as a psychiatric co-morbidity. Elderly transplant recipients with depressive disorders are a vulnerable group and multidisciplinary teams such as psychiatry and palliative care should be involved in their care.