Dhenuka Kannan Radhakrishnan1, Sharon D Dell2, Astrid Guttmann3, Salimah Z Shariff4, Kuan Liu4, Teresa To5. 1. Children's Hospital, London Health Sciences Centre, London, Ontario, Canada; Department of Pediatrics, Western University, London, Ontario, Canada; Institute for Clinical Evaluative Sciences, London, Ontario, Canada. Electronic address: dhenuka@gmail.com. 2. Division of Respiratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada. 3. Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada; Division of Pediatric Medicine, Hospital for Sick Children, Toronto, Ontario, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada. 4. Institute for Clinical Evaluative Sciences, London, Ontario, Canada. 5. Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Child Health Evaluative Sciences, Hospital for Sick Children, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
Abstract
BACKGROUND: The cause of rising asthma incidence over time remains unexplained. Examining trends in the age of diagnosis across successive birth cohorts may offer insights into asthma etiology. OBJECTIVE: To examine trends in the age at asthma diagnosis and the age and proportion of children hospitalized at first asthma diagnosis in Ontario, Canada. METHODS: Eight consecutive birth cohorts of children (1993-2000) were observed using administrative data from a universal health insurance plan in Ontario, Canada (population 13 million). Trends in the need for hospitalization and age at asthma diagnosis were examined with descriptive and survival analyses. RESULTS: The records of 1,059,511 children were examined, of whom 201,958 developed asthma in the first 8 years of life, with an average cumulative incidence of 19.1%. Mean age at asthma diagnosis decreased from 4.7 ± 1.5 years in birth year 1993 to 2.6 ± 2.0 years in birth year 2000 (P < .0001), with a higher adjusted risk of asthma diagnosis (hazard ratio, 6.7; 95% CI, 6.5-6.9) in the first 3 years of life for children born after 1996 versus children born in the period 1993 to 1995 (hazard ratio, 1.4; 95% CI, 1.3-1.4). The proportion of children hospitalized at asthma diagnosis stayed stable while the age at first asthma hospitalization decreased over time (P < .0001). CONCLUSIONS: This study demonstrates a significant increase in asthma incidence and a decrease in the age of asthma diagnosis across multiple birth cohorts. Changes in asthma incidence over time are primarily explained by variations in asthma rates in children younger than 3 years.
BACKGROUND: The cause of rising asthma incidence over time remains unexplained. Examining trends in the age of diagnosis across successive birth cohorts may offer insights into asthma etiology. OBJECTIVE: To examine trends in the age at asthma diagnosis and the age and proportion of children hospitalized at first asthma diagnosis in Ontario, Canada. METHODS: Eight consecutive birth cohorts of children (1993-2000) were observed using administrative data from a universal health insurance plan in Ontario, Canada (population 13 million). Trends in the need for hospitalization and age at asthma diagnosis were examined with descriptive and survival analyses. RESULTS: The records of 1,059,511 children were examined, of whom 201,958 developed asthma in the first 8 years of life, with an average cumulative incidence of 19.1%. Mean age at asthma diagnosis decreased from 4.7 ± 1.5 years in birth year 1993 to 2.6 ± 2.0 years in birth year 2000 (P < .0001), with a higher adjusted risk of asthma diagnosis (hazard ratio, 6.7; 95% CI, 6.5-6.9) in the first 3 years of life for children born after 1996 versus children born in the period 1993 to 1995 (hazard ratio, 1.4; 95% CI, 1.3-1.4). The proportion of children hospitalized at asthma diagnosis stayed stable while the age at first asthma hospitalization decreased over time (P < .0001). CONCLUSIONS: This study demonstrates a significant increase in asthma incidence and a decrease in the age of asthma diagnosis across multiple birth cohorts. Changes in asthma incidence over time are primarily explained by variations in asthma rates in children younger than 3 years.
Authors: Azar Mehrabadi; Linda Dodds; Noni E MacDonald; Karina A Top; Eric I Benchimol; Jeffrey C Kwong; Justin R Ortiz; Ann E Sprague; Laura K Walsh; Kumanan Wilson; Deshayne B Fell Journal: JAMA Date: 2021-06-08 Impact factor: 56.272
Authors: Michelle K Trivedi; Sunita Sharma; Sheryl L Rifas-Shiman; Carlos A Camargo; Scott T Weiss; Emily Oken; Matthew W Gillman; Diane R Gold; Dawn L DeMeo; Augusto A Litonjua Journal: Clin Pediatr (Phila) Date: 2017-09-08 Impact factor: 1.168
Authors: Dhenuka Radhakrishnan; Sarah E Bota; April Price; Alexandra Ouédraogo; Murad Husein; Kristin K Clemens; Salimah Z Shariff Journal: CMAJ Open Date: 2021-05-04
Authors: Harsheen Kaur; Sunghwan Sohn; Chung-Il Wi; Euijung Ryu; Miguel A Park; Kay Bachman; Hirohito Kita; Ivana Croghan; Jose A Castro-Rodriguez; Gretchen A Voge; Hongfang Liu; Young J Juhn Journal: BMC Pulm Med Date: 2018-02-13 Impact factor: 3.317