Skip Navigation Links
ICD Code: 493. Asthma

ICD Code: 493. Article Review
Title: Simpson CR et al; "Trends in the Epidemiology of Asthma in England: A National Study of 333,294 Patients." Journal of the Royal Society of Medicine; V.103; 2010; p98     DOI:10.1258/jrsm.2009.090348
      STUDY DESIGN: This study of national trends in the epidemiology of asthma was commissioned by the Chief Medical Officer for England because of growing concern about the high prevalence, disease burden and healthcare costs. Version 10 of the QRESEARCH database was used for these analyses. This database contains broadly representative anonymized aggregated health data derived from 422 primary care practices throughout England. Data were available for each year during the period 1 January 2001-31 December 2005; these data comprise between 2.8 and 3 million individual patients who collectively contributed over 30 million patient-years of observation. Patients were characterized by gender and age. Incidence was defined as the number of patients with a new case of asthma diagnosed in a specific year. Lifetime prevalence was defined as the number of people with asthma ever recorded on at least one occasion in the general practice (GP) records. Asthma was defined as patients who have Read codes H33 and below.
      INCIDENCE TRENDS (ENGLAND): The incidence of asthma per 1000 patient-years was reported as follows: 2001, 6.9; 2002, 6.7; 2003, 6.1; 2004, 6.4; 2005, 5.2. The relative percentage change in incidence rate from 2001 to 2005 was reported as follows: women, -23.2%; men, -25.8%; ages 0-4 years, -38.4%; ages 5-14 years, -27.0%; ages 15-44 years, -12.6%; ages 45-64 years, -15.7%; ages 65 and older, -21.1%.
      Between 2001 and 2005, there was a decrease in the incidence rate of asthma in England. Decreases in incidence were found in all groups of patients, the largest of which was in pre-school children (i.e., under 5 years).
      PREVALENCE TRENDS: The age- and sex-standardized lifetime prevalence of asthma per 1000 patients was reported as follows: 2001, 100.5; 2002, 104.8; 2003, 108.5; 2004, 111.9; 2005, 113.0. The relative percentage change in incidence rate from 2001 to 2005 was reported as follows: women, 13.8%; men, 25.8%; ages 0-4 years, -34.3%; ages 5-14 years, -4.4%; ages 15-44 years, 23.3%; ages 45-64 years, 27.7%; ages 65 and older, 21.5%.
      Over the study period, the recorded lifetime prevalence of asthma increased. Significant decreases in lifetime prevalence over time were found in pre-school and school-aged children. Significant increases occurred in all other age groups.
      PRESCRIPTION TRENDS: The rate of asthma-related prescriptions per 1000 patients increased during the study period from 556.6 per 1000 in 2001 to 650.3 per 1000 patients in 2005, representing a 17.1% rise. Older patients (over 65 years) received the most prescriptions per head of population.
      SOCIOECONOMIC STATUS: There were substantial socioeconomic differences found in the rates of asthma, with the most deprived (quintile 5) having higher incidence and lifetime prevalence of asthma and higher rates of being prescribed asthma-related drugs than the most affluent patients.
      DISCUSSION: This large national study reveals that the rate of new diagnoses of asthma appears to have passed its peak. However, the number of adults with a lifetime asthma diagnosis continues to rise.
      The authors estimated that 261,400 of 50 million people in England were newly diagnosed with asthma in 2005. They estimated that 5,658,900 had a GP recorded diagnosis of asthma, this translating into approximately 1 person in 9 being diagnosed with asthma at some point in their lives. An estimated 3,257,000 people with asthma were prescribed an asthma-related drug. An estimated total of 32,577,300 asthma-related prescriptions were issued to patients in England in 2005.

Search Criteria: Text - Journal of the Royal Society of Medicine; V.103; 2010; p98