Low, rather than High, Body Mass Index Is a Risk Factor for Acute Kidney Injury in Multiethnic Asian Patients: A Retrospective Observational Study

Table 2

Primary diagnosis of hospitalised patients with acute kidney injury according to ICD-9 codes and KDIGO classification.

Primary diagnosis	Total	No acute kidney injury (%)	Acute kidney injury (%)	value
Total number	12555	10949	1606
Diseases of the respiratory system	1625 (12.9)	1398 (12.8)	227 (14.1)	0.128
Symptoms, signs, and ill-defined conditions	1547 (12.3)	1404 (12.8)	144 (8.9)	<0.001
Diseases of the circulatory system	1505 (12.0)	1305 (11.9)	202 (12.5)	0.538
Diseases of the digestive system	1423 (11.3)	1263 (11.5)	160 (10.0)	0.063
Diseases of the musculoskeletal system and connective tissue	1104 (8.8)	1020 (9.3)	84 (5.2)	<0.001
Diseases of the nervous system	1029 (8.2)	915 (8.4)	114 (7.1)	0.086
Diseases of the genitourinary system	966 (7.7)	760 (6.9)	206 (12.8)	<0.001
Infectious and parasitic diseases	925 (7.4)	742 (6.8)	183 (11.4)	<0.001
Diseases of the skin and subcutaneous tissue	645 (5.1)	581 (5.3)	65 (4.0)	0.025
Endocrine, nutritional, and metabolic diseases and immunity disorders	536 (4.3)	469 (4.3)	67 (4.2)	0.836
Neoplasm	438 (3.5)	350 (3.2)	88 (5.5)	<0.001
Injury	303 (2.4)	283 (2.6)	20 (1.2)	0.001
Poisoning and toxic effects	177 (1.4)	162 (1.5)	15 (0.9)	0.083
Diseases of the blood and blood-forming organs	129 (1.0)	108 (1.0)	21 (1.3)	0.233
Diseases of the sense organs (e.g., eyes, ears)	95 (0.8)	90 (0.8)	5 (0.3)	0.027
Mental disorders	66 (0.5)	64 (0.6)	2 (0.1)	0.017
Complications of medical care	42 (0.3)	35 (0.3)	7 (0.4)	0.451
Complications of pregnancy, childbirth, and the puerperium	0 (0)	0 (0)	0 (0)	-
Congenital anomalies	0 (0)	0 (0)	0 (0)	-
Certain conditions originating in the perinatal period	0 (0)	0 (0)	0 (0)	-