Burden of acute respiratory infections across Western Australian emergency departments Rosanne Barnes, Chris C. Blyth, Nick de Klerk, Peter Richmond, Meredith Borland, Parveen Fathima, Faye J. Lim & Hannah C. Moore Acute Lower Respiratory Infections (ALRI) Globally responsible for ~1 in 5 deaths in children <5 years and are a major cause of childhood morbidity 1 Most information is on hospital burden Severe end of clinical spectrum Rate of hospitalisation for ALRI in Western Australia 2 children 276.1/1000 (<12 months) Non- children 44.7/1000 (<12 months) Respiratory virus and/or bacterial pathogen identified in 58% WA hospitalisations 3 1 Black RE, et al. 2010. Lancet. 2010 2 Moore HC, et al. 2010. BMC Public Health 3 Moore HC, et al. 2012. J Paediatr Child Health 1
Out-of-hospital burden Hospitalisation usually only after presenting to GP/ED Out-of-hospital burden of acute respiratory infections (ARIs) in Western Australian (WA) and non- children unknown Parent-reported data indicated ARI incidence rate of 0.56/child-month in children <2 years in Melbourne 4 & Brisbane 5 Previous work on WA EDs (2001-2005) 53% ICD-coded diagnosis were for ALRI 6 4 Lambert SB, et al. 2007. Pediatr 5 Sarna M, et al. 2016. Pediatr Pulmonol 6 Moore HC, et al. 2012. BMC Public Health Aim To examine diagnosis information from WA ED presentation records from 2002 to 2012 in order to describe the overall and age-specific burden of ARIs among WA and non- children and compare across WA regions 2
Geographical Regions WA total population 2.6 million - 79% reside in Perth - 6.4% Climate varies across WA - Mediterranean climate metropolitan WA (Perth) & south - More tropical climates in northern regions Map source: Hogan et al. 2016. Epidemics. Datasets used DEATH REGISTRY All deaths registered in WA BIRTH REGISTRY All births registered in WA MIDWIVES NOTIFICATION All midwife-attended births Merged birth cohort (1996-2012) n=469,589 persons HOSPITAL MORBIDITY All public and private hospitals in WA PATHWEST LABORATORY Pathology services to all public hospitals in WA EMERGENCY DEPARTMENT (ED) ED activity in public hospitals in metropolitan WA WA NOTIFIABLE INFECTIOUS DISEASES All clinical and laboratory detections of notifiable disease cases in WA WA=Western Australia 3
The Emergency Department Data Collection (EDDC) & linked datasets Four data collection systems contribute to EDDC: Emergency Department Information System (EDIS) all public metropolitan hospital EDs & one private The Open Patient Administration System (TOPAS) one rural hospital ED (Bunbury) Health Care and Related Information System (HCARe) most other rural & remote EDs Electronic Patient Administration System (epas) one private metropolitan hospital ED (Mandurah) Diagnoses, symptoms & demographic information Linked to merged birth cohort (birth/death dates, postcode at birth) ARI coding Variable Description 1. Principal Diagnosis ICD-10 code 2. Symptom Symptom code 3. Diagnosis at discharge Text variable (freehand) 4. Presenting complaint (symptom) Text variable (freehand) 5. Major diagnostic category Broad disease categories ( diseases and disorders of the respiratory system ) 4
ED dataset & coding variables ED presentations 2002-2012 N=1,615,520 Linkable ED presentations 2002-2012 N=1,607,825 Linkable ED presentations 2002-2012 N=1,606,257 Records with inconsistent birth dates or non-wa postal code excluded n=7,695 Records missing postal code excluded n=1,568 Coded by ICD n=277,850 Coded by symptom code n=4,426 Coded by diagnosis at discharge text n=9,093 Coded by presenting complaint text n=13,486 Coded by major diagnostic category n=113,900 Presentation for ARI Overall 26% ED presentations were for ARI (n=418,755) 32% in children <5 72% children presented to ED 1 40% children presented to ED for ARI 1 33% children presented to ED for ARI before their 5 th birthday 5
Categories of ARI 0 20,000 40,000 60,000 80,000 100,000 120,000 Respiratory disease Viral Illness Other upper respiratory Croup Bronchiolitis Asthma Fever Tonsillitis Otitis Media Wheeze/cough/crackles Pneumonia Febrile convulsions Unspecified ALRI Influenza Bronchitis Pertussis Other lower respiratory Presentations for specific conditions Non- Age group Number Rate* 95% CI Number Rate* 95% CI <12 months Bronchiolitis 2,342 112.9 108.4,117.6 16,252 55.7 54.9,56.6 Croup 260 12.5 11.1,14.2 4,662 16.0 15.5,16.4 Other upper respiratory 1,889 91.1 87.0,95.3 17,040 58.4 57.6,59.3 Viral illness 1,443 69.6 66.0,73.3 17,163 58.9 58.0,59.7 Respiratory 13,817 666.1 655.1,677.3 17,009 58.3 57.5,59.2 disease ARI 21,316 1,027.6 1,013.9,1,041.5 86,710 297.4 295.4,299.3 *Rate per 1000 child years at risk from Western Australian live births 6
Presentations for specific conditions Non- Age group Number Rate* 95% CI Number Rate* 95% CI 1-4 years Bronchiolitis 388 4.8 4.3,5.3 3,441 3.1 3.0,3.2 Croup 899 11.2 10.4,11.9 21,133 19.2 18.9,19.4 Other upper respiratory 2,256 28.0 26.9,29.2 30,464 27.7 27.3,28.0 Viral illness 2,013 25.0 23.9, 26.1 38,024 34.5 34.2,34.9 Respiratory disease 18,762 232.9 229.5,236.2 40,461 36.7 36.4,37.1 ARI 28,381 352.2 348.2,356.4 195,742 177.7 176.9,178.5 *Rate per 1000 child years at risk from Western Australian live births <12 months ARI Rate/1000 child years Non- 900.0 375.7 1,088.4 324.8 991.3 355.3 912.1 316.0 1,009.9 293.3 910.8 289.0 934.9 400.3 1,233.6 314.3 7
1-4 years ARI Rate/1000 child years Non- 322.4 216.4 364.6 172.8 336.3 197.3 274.9 164.4 354.5 170.5 311.8 173.7 356.5 244.2 456.7 184.4 Conclusions & next steps 1 in 4 ED presentations were for ARIs substantial out-of-hospital burden Some evidence of geographical disparity highest rates South and North of the State Proportion of presentations missing ICD diagnosis and/or with limited or unclear information leaves a gap in the overall ED picture Planned linkages with hospital discharge diagnosis data will aid in assessing the sensitivity & specificity of ARI diagnoses in ED 8
Acknowledgements Project Grant APP1045668 HCM Fellowship APP1034254 CCB Fellowship APP1111596 Friends of the Institute Friends of the Institute Travel Award RB Western Australian Data Linkage Branch Alexandra Merchant, Mikhalina Dombrovskaya Data collections and custodians No conflicts of interest to declare Supplementary table. Emergency department acute respiratory infections categories and variable components Category N Percentage of International Classification of Diseases or Symptom code Key words for text variables presentations Major Diagnostic Category 1. Pertussis/Whooping cough 710 0.0 A37 Whooping cough SNJ Pertussis/whooping cough Pertussis; whooping cough; post-tussive vomiting 2. Pneumonia 10,322 0.6 J12 Viral pneumonia, not elsewhere SQJ Pneumonia Pneumonia classified J13 Pneumonia due to Streptococcus pneumoniae J14 Pneumonia due to Haemophilus influenzae J15 Bacterial pneumonia, not elsewhere classified J16 Pneumonia due to other infectious organisms, not elsewhere classified J17 Pneumonia in diseases classified elsewhere J18 Pneumonia, organism unspecified J10.0 Influenza with pneumonia, other influenza identified J11.0 Influenza with pneumonia, virus not identified 3. Bronchiolitis 22,446 1.4 J21 Acute bronchiolitis Bronchiolitis 4. Influenza 1,774 0.1 J09 Influenza due to certain identified influenza virus J10.1 Influenza with other respiratory manifestations, other influenza virus identified J10.8 Influenza with other manifestations, other influenza virus identified J11.1 Influenza with other respiratory manifestations, virus not identified J11.8 Influenza with other manifestations, virus not identified AAV Flu Like Symptoms Influenza; flu; flu-like symptoms 9
1. Unspecified ALRI (includes chest infection & LRTI) 3,780 0.2 J22 Unspecified acute lower respiratory infection 2. Bronchitis 1,234 0.1 J20 Acute bronchitis J40 Bronchitis, not specified as acute or chronic 3. Croup 32,480 2.0 J05.0 Acute obstructive laryngitis [croup] R06.1 Stridor 4. Convulsions/Febrile convulsions 5. Wheeze/cough/ crackles 9,554 0.6 R56.0 Febrile convulsions R56.8 Other and unspecified convulsions 10,564 0.7 R06.2 Wheezing R05 Cough SQD Chest infection SQC Bronchitis CG Stridor SNG Febrile convulsion CH Wheeze CC Cough Unspecified Acute Lower Respiratory Infection; LRTI; lower respiratory tract infection; chest infection Bronchitis Croup; Laryngotracheobronchitis; barking cough; stridor Febrile convulsion; convulsion Wheeze; wheezing; cough; crackles 6. Viral illness 72,927 4.5 B34 Viral infection of unspecified site Viral respiratory infection; viral respiratory tract infection; rhinorrhoea; acute viral infection; viral infection; viral illness 7. Fever/Pyrexia 18,423 1.1 R50 Fever of other and unknown origin S2B Pyrexia of unknown origin VP Pyrexia of unknown origin VD Fever PG Febrile AAU Fever Fever; pyrexia; febrile; high temperature 8. Otitis Media 15,873 1.0 H65-H67 Otitis media Otitis media 9. Tonsillitis 16,541 1.0 J03 Acute tonsillitis Tonsillitis 10. Other upper FE Nasal discharge respiratory diseases 61,563 3.8 J06 Acute Upper Respiratory Infections J00 Acute nasopharyngitis J01 Acute sinusitis J02 Acute pharyngitis J04 Acute laryngitis and tracheitis Upper respiratory tract infection; URTI; nasopharyngitis; sinusitis; pharyngitis; laryngitis; tracheitis; epiglottitis; 1. Other lower respiratory diseases 543 0.0 J41 Simple and mucopurulent chronic bronchitis J42 Unspecified chronic bronchitis J43 Emphysema J44 Other chronic obstructive pulmonary disease J47 Bronchiectasis J60-J70 Lung diseases due to external agents J80-J84 Other respiratory diseases principally affecting the interstitium J85-J86 Suppurative and necrotic conditions of lower respiratory tract J90-J94 Other diseases of pleura 2. Respiratory disease 118,251 7.4 MDC 4 Diseases and disorders of the respiratory system J95-J99 Other diseases of the respiratory system 3. Asthma 21,770 1.4 J45 Asthma J46 Status asthmaticus Total ARI 418,755 26.1 C0000 Respiratory CJ Respiratory distress SQA Asthma & Status asthmaticus Bronchiectasis; chronic bronchitis; chronic obstructive pulmonary disease; emphysema Respiratory tract infection; RTI; respiratory infection; respiratory problems; respiratory distress Asthma 10
WA metro EDs Armadale/Kelmscott District Memorial Hospital Fiona Stanley Hospital Joondalup Health Campus King Edward Memorial Hospital For Women Princess Margaret Hospital For Children* Rockingham General Hospital Royal Perth Hospital Sir Charles Gairdner Hospital St John of God Midland Public Hospital 11