Autonomic Function in Insular Glioma: An Exploratory Study

Autonomic nervous system dysfunction is a known entity in strokes involving insula. It causes significant morbidity and mortality. No study to date has demonstrated autonomic nervous system dysfunction in patients with insular glioma. This is an exploratory study to identify the subclinical autonomic dysfunctions in insular glioma. A total 50 patients with newly diagnosed insular glioma in the age group of 18–60 years were evaluated with heart rate variability (HRV). All the HRV parameters in patients with insular glioma were compared with normal healthy age- and sex-matched control patients. There was a significant difference (P < 0.05) in most of the HRV parameters between patients and control patients. Patients with left insular glioma showed significantly increased heart rate (P = 0.027), low-frequency normalized units (P = 0.048), and also increased low-frequency/high-frequency ratio (P = 0.015), which indicates sympathetic dominance. Patients with seizures had significantly lower values of total power (P = 0.042). No significant difference was found in terms of the extent and size of the tumor or histopathologic grades of gliomas. Patients with insular gliomas have significant impairment of autonomic functions, with left insular glioma showing sympathetic dominance. Suppression of autonomic function is greater in those presenting with seizures. •Autonomic dysfunction is known in strokes involving insula.•This is the first study demonstrating autonomic dysfunction in patients with insular glioma.•Patients with insular gliomas has a significant change in heart rate variability.•Patients with left insular glioma have sympathetic dominance.•Patients with insular glioma and seizures have more impairment of autonomic function.