Clinical Profile of Cerebral Venous Sinus Thrombosis in High Altitude: An Experience from North Eastern India

Introduction: Cerebral venous sinus thrombosis (CVST) is a rare cause of stroke. There have been limited studies on the clinical profile of patients with CVST on exposure to high altitude in the Indian settings. CVST may present with myriad of clinical features and is an important neurological illness presenting in the high altitude. Aims and Objectives: The aim of the study was to describe the clinical profile of patients with CVST who had the onset on exposure to high altitude. We also compared clinical features and various laboratory parameters of these patients with patients of CVST who did not have any exposure to high altitude. Methods: Ours was an ambispective study carried out at a tertiary care center in North Eastern India. Patient population consisted of radiologically confirmed cerebral venous sinus thrombosis(CVST) managed at our center between June 2020 and July 2023. Patients who were native highlanders (permanent residents of altitude>2500 meters above the sea level) were excluded from the study. The patients were further subdivided into two groups, High altitude area(HAA) group which had onset of symptoms in high altitude and non HAA group which had onset of symptoms at normal altitude. The demographic, clinical, laboratory and radiological findings were recorded and both the groups were compared for any differences. Results: A total of 57 patients were included in the study. Thirty-two had the onset of the symptoms in high altitude and 25 had no exposure to high altitude at the onset of symptoms. Most of the patients were males in both the groups. The patients in HAA had longer duration of symptoms before the definitive diagnosis, had greater mean hemoglobin levels and higher median homocysteine levels and had evidence of thrombosis at other anatomical sites such as portal veins. There was no mortality in any of the groups. Conclusion: CVST at high altitude is associated with higher hemoglobin levels. The diagnosis takes longer time than those who present in normal altitudes. Well-designed studies are required to study the various other factors such as homocysteine in causation of CVST at high altitude.