Article Text
Abstract
Asthma attacks occur across all subtypes and severities of disease. Accurate quantification of asthma attack risk would enable targeting of interventions with a potential reduction in morbidity, mortality, and costs. We aimed to develop a risk assessment questionnaire underpinned by a systematic literature review.
We searched major databases up to February 2012 using the terms: asthm* AND (exacerbati* OR admission) AND (risk OR predic* OR associat*) NOT review.
Included studies were those in individuals >12 years old with doctor-diagnosed asthma on treatment. Outcomes were asthma attacks defined as: deterioration of symptoms, fall in objective measures of airflow, and need for a short course of augmented asthma therapy OR admission to hospital OR attendance at emergency department. Statistical analysis was carried out using RevMan 5 and SPSS 19.
3536 unique publications were retrieved. After title screening and comparison of abstracts against a standard checklist and age criteria, data extraction was undertaken in duplicate on the remaining 143 papers (see figure).
Of 18 major research themes identified, 8 factors had a consistent and clinically important (OR>1.25) association with asthma attacks across publications free from major bias. The questionnaire derived from these factors is shown below. Simplified weighting is proportional to the effect size when expressed as an odds ratio (in brackets).
I smoke (3)
I take fewer than 8 out of 10 prescribed doses of my regular preventer medication (3)
In the last month I have used my reliever inhaler more than once per day on average (3)
I sneeze, or get a runny, or a blocked nose when I do not have a cold (2)
In the last 5 years, I have attended a hospital emergency department or been admitted to hospital because of asthma (2)
I have a body mass index of ≥ 30 (1)
I have not received asthma related education or a written asthma management plan (1)
I left school before sitting my A-levels/highers (1)
In summary, we systematically identified factors from the literature that are independently associated with the risk of asthma attack. These factors inform a questionnaire which will require validation and subsequent impact assessment.