# Severe temozolomide-induced thrombocytopenia is linked to increased healthcare utilization in glioblastoma and disproportionally impacts female patients

## TL;DR

Severe temozolomide-induced low platelet counts in glioblastoma patients increase healthcare use, especially in women.

## Contribution

This study reveals that severe thrombocytopenia disproportionately increases healthcare utilization in female glioblastoma patients.

## Key findings

- Thrombocytopenia occurred in 61.1% of glioblastoma patients treated with temozolomide.
- Female patients with grade 4 thrombocytopenia had significantly higher healthcare utilization (OR=5.9) compared to males (OR=4.4).
- Grade 4 thrombocytopenia during the adjuvant phase was strongly associated with increased healthcare use (OR=7.6).

## Abstract

Thrombocytopenia is a major temozolomide-induced adverse event during the standard treatment of glioblastoma. Consequently, platelet transfusions and treatment modifications may impact quality of life and long-term treatment outcomes. Understanding the impact of thrombocytopenia on healthcare utilization is crucial to mitigate the need for healthcare resources in glioblastoma patients. Here, we assess the influence of thrombocytopenia-related healthcare among patients diagnosed with glioblastoma.

We retrospectively collected patient information treated at the Brain Tumor Center Amsterdam between 2008 and 2021. The occurrence of thrombocytopenia, patient demographics, treatment details, and healthcare utilization data were gathered from patients who received standard glioblastoma treatment. Associations between temporal severity of thrombocytopenia as categorized by the Common Terminology Criteria for Adverse Events, patient characteristics, and healthcare utilization were analyzed using Generalized Linear Mixed Models.

We included 206 patients with a median age of 58 years, 35.9% were female and we found that thrombocytopenia (any grade) occurred in 61.1% of patients. The occurrence of thrombocytopenia during CRT was associated with increased healthcare utilization and was largest in females who developed grade 4 thrombocytopenia compared to those who did not develop thrombocytopenia (OR = 5.9, P < .001 in females vs OR = 4.4, P < .001 in males). Grade 4 thrombocytopenia was also associated with heightened healthcare utilization during the adjuvant phase (OR = 7.6, P < .001), and was comparable between sexes.

Severe thrombocytopenia during glioblastoma treatment is linked to increased healthcare utilization, disproportionally impacting females. These data suggest that prevention and early management of thrombocytopenia can reduce healthcare utilization in patients with glioblastoma.