Explainable Deep Learning Model for Predicting Serious Adverse Events in Hospitalized Geriatric Patients Within 72 Hours

Figures & data

Figure 1 Patient inclusion flow chart and the development of the deep learning model.

Table 1 Characteristics of Patients in Development and Test Data Set

	Data Set
	Development Set N= 103,411	Test Set N= 23,857	p-value
Age, year-old, Mean±SD	78.5 ± 7.87	78.5 ± 7.97	0.417
Male, N (%)	55,141 (53.3)	12,523 (52.5)	0.021
Vital Sign at Triage, Mean±SD
Temperature	36.9 ± 1.08	37.1 ± 1.11	<0.001
Heart Rate	93.3 ± 21.5	92.9 ± 21.4	<0.001
Systolic Blood Pressure	140.5 ± 32.8	141.8 ± 32.3	<0.001
Diastolic Blood Pressure	78.0 ± 17.2	77.4 ± 16.9	<0.001
Respiratory Rate	20.2 ± 3.4	19.6 ± 3.4	<0.001
Shock index	0.71 ± 0.26	0.69 ± 0.25	<0.001
Glasgow Coma Scale	13.8 ± 2.6	13.8 ± 2.6	0.952
Vital Sign at Admission, Mean±SD
Temperature	36.4 ± 0.65	36.5 ± 0.68	<0.001
Heart Rate	83.3 ± 17.0	82.6 ± 16.9	<0.001
Systolic Blood Pressure	133.8 ± 24.0	134.2 ± 24.0	0.015
Diastolic Blood Pressure	75.6 ± 14.1	73.9 ± 14.2	<0.001
Respiratory Rate	18.5 ± 2.7	18.0 ± 2.7	<0.001
Shock Index	0.65 ± 0.19	0.64 ± 0.19	<0.001
Glasgow Coma Scale	13.9 ± 2.3	13.8 ± 2.3	0.001
Underlying Medical History, N (%)
Hypertension	56,633 (54.8)	13,307 (55.8)	0.005
Diabetes Mellitus	38,929 (37.6)	9694 (40.6)	<0.001
Liver Cirrhosis	9463 (9.2)	2111 (8.8)	0.144
Old Stroke	22,080 (21.4)	5366 (22.5)	<0.001
Heart Failure	16,949 (16.4)	3992 (16.7)	0.198
End stage renal disease	29,175 (28.2)	7234 (30.3)	<0.001
Malignancy	28,402 (27.5)	6911 (29.0)	<0.001
Outcome, N (%)
Adverse Event	2765 (2.7)	572 (2.4)	0.016
Cardiac Arrest	258 (0.2)	44 (0.2)	0.063
Mechanical Ventilation	2441 (2.4)	504 (2.1)	0.022
ICU transfer	2560 (2.5)	540 (2.3)	0.008

Table 2 Clinical Features Associated with Adverse Event During Admission

	Without Adverse Event N= 123,931	With Adverse Event N= 3337	p-value
Age, year-old, Mean±SD	78.4 ± 7.88	79.5 ± 7.95	<0.001
Male	65,831 (53.1)	1833 (54.9)	0.039
Vital Sign at Triage, Mean±SD
Temperature	36.9 ± 1.09	37.0 ± 1.12	0.012
Heart Rate	93.0 ± 21.4	100.2 ± 23.3	<0.001
Systolic Blood Pressure	140.8 ± 32.7	138.0 ± 33.1	<0.001
Diastolic Blood Pressure	77.9 ± 17.1	78.1 ± 18.4	0.627
Respiratory Rate	20.0 ± 3.4	22.5 ± 4.8	<0.001
Shock index	0.70 ± 0.25	0.76 ± 0.27	<0.001
Glasgow Coma Scale	13.8 ± 2.6	13.7 ± 2.7	0.042
Vital Sign at Admission, Mean±SD
Temperature	36.4 ± 0.66	36.5 ± 0.74	<0.001
Heart Rate	82.9 ± 16.8	93.0 ± 20.5	<0.001
Systolic Blood Pressure	134.0 ± 24.0	130.2 ± 24.2	<0.001
Diastolic Blood Pressure	74.5 ± 14.1	72.1 ± 15.6	<0.001
Respiratory Rate	18.4 ± 2.6	20.8 ± 4.8	<0.001
Shock Index	0.64 ± 0.19	0.74 ± 0.23	<0.001
Glasgow Coma Scale	13.9 ± 2.3	13.8 ± 2.4	0.364
Laboratory test
WBC	10.4 ± 8.5	12.1 ± 12.0	<0.001
Segment, %	75.4 ± 12.9	75.8 ± 12.8	<0.001
Band, %	0.42 ± 1.86	0.87 ±2.88	<0.001
Hemoglobin	11.3 ± 2.3	11.1 ± 2.4	<0.001
Platelet	212.2 ± 99.7	210.3 ± 98.6	0.289
Sugar	164.8 ± 84.5	176.4 ± 92.7	<0.001
Creatinine	1.81 ± 1.88	1.96 ± 1.94	<0.001
AST	32.0 ± 125.9	39.7 ± 201.6	0.029
ALT	33.7 ± 97.8	35.6 ± 72.3	0.259
Total bilirubin	1.1 ± 1.65	1.0 ± 1.42	0.037
Sodium	135.2 ± 5.7	135.2 ± 7.0	0.127
Potassium	4.0 ± 0.62	4.1 ± 0.71	<0.001
CRP	61.6 ± 64.8	79.0 ± 79.6	<0.001
Albumin	4.2 ± 0.42	4.1 ± 0.48	<0.001
Troponin	0.08 ± 1.27	0.26 ± 3.02	0.001
Blood pH	7.4 ± 0.03	7.4 ± 0.05	<0.001
Underlying Medical History
Hypertension	68,144 (55.0)	1796 (53.8)	0.182
Diabetes Mellitus	47,362 (38.2)	1261 (37.8)	0.616
Liver Cirrhosis	11,361 (9.2)	213 (6.4)	<0.001
Old Stroke	26,772 (21.6)	674 (20.2)	0.052
Heart Failure	20,030 (16.2)	911 (27.3)	<0.001
End stage renal disease	35,420 (28.6)	989 (29.6)	0.182
Malignancy	34,466 (27.8)	847 (25.4)	0.002
ED management
Low Flow Oxygen Support	52,107 (42.0)	2262 (67.8)	<0.001
High Flow Oxygen Support	3574 (2.9)	592 (17.7)	<0.001
Fluid Challenge	16,014 (12.9)	718 (21.5)	<0.001
Inotropics	1905 (1.5)	176 (5.3)	<0.001

Figure 2 The Receiver Operating Characteristic (ROC) curve of model prediction.

Figure 3 Global Explanation of feature importance by SHapley Additive exPlanations (SHAP) value. Sum_gcs_e: The sum of the Glasgow Coma Scale scores when the patient left the emergency department to ward admission. Shock_index_e: Shock index (dividing the heart rate by the systolic blood pressure) when the patient left the emergency department to ward admission.

Abbreviations: Na, sodium level; DM, diabetes mellitus; DBP_e, Diastolic blood pressure when the patient left the emergency department to ward admission; Hb, Hemoglobin; WBC, White blood cells; RR_a, Respiratory rate during emergency department triage; K, potassium level.

Data Sharing Statement

The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.