hat_score_tpa_hemorrhage: HAT Score for Predicting Post-tPA Hemorrhage

In cliot: Clinical Indices and Outcomes Tools

HAT Score for Predicting Post-tPA Hemorrhage

Description

Calculates the HAT score to predict the risk of symptomatic intracranial hemorrhage (sICH) following thrombolysis with tPA for acute ischemic stroke. The score is based on four independent predictors: History of diabetes, Age (though age is not in the final simplified score, the acronym stands for Hemorrhage After Thrombolysis), Tpa-pretreatment glucose, and NIHSS score, plus identifiable hypodensity on initial CT.

Usage

hat_score_tpa_hemorrhage(nihss_score, history_of_diabetes, glucose_mg_dl,
                         history_of_signs_of_early_infarct)

Arguments

nihss_score	Numeric. Pre-treatment NIH Stroke Scale score. (<15: 0 pts, 15-20: 1 pt, >20: 2 pts).
history_of_diabetes	Numeric (0 or 1). History of diabetes mellitus. (1 = Yes, +1 pt).
glucose_mg_dl	Numeric. Pre-treatment glucose level in mg/dL. (>= 200 mg/dL adds 1 pt).
history_of_signs_of_early_infarct	Numeric (0 or 1). Evidence of early infarct signs on initial CT (e.g., hypodensity, loss of grey-white differentiation). (1 = Yes, +1 pt).

Value

A list containing:

HAT_Score	The calculated score (Range 0-5).
Risk_Category	Classification of risk (Low, Moderate, High, Very High).
Risk_of_Symptomatic_Intracranial_Hemorrhage	Estimated percentage risk of sICH.

References

Lou M, Safdar A, Mehdiratta M, et al. The HAT Score: a simple grading scale for predicting hemorrhage after thrombolysis. Neurology. 2008;71(18):1417-1423. doi:10.1212/01.wnl.0000330297.58383.35

Examples

# Example 1: High Risk
# NIHSS 18 (+1), Diabetes (+1), Glucose 220 (+1), CT Signs (+1)
# Score = 4
hat_score_tpa_hemorrhage(18, 1, 220, 1)

# Example 2: Low Risk
# NIHSS 10 (0), No Diabetes, Glucose 100, No CT signs
# Score = 0
hat_score_tpa_hemorrhage(10, 0, 100, 0)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.