BACKGROUND: Prevalence surveys are important to aid in assessing the current burden of diseases, which will impact on the public health agenda as well as preventive interventions and health policies. Three previous local surveys on asthma prevalence of Filipino adults have been carried out. This is the fourth local survey and is also a part of the second NNHeS study, which is carried out every five years. The purpose of the survey is to determine the trend in asthma prevalence and to aid in formulating and evaluating local initiatives.
OBJECTIVE: To determine the prevalence of asthma among Filipino adults
METHODOLOGY: Using a multi-staged cluster sampling methodology, this study evaluated 7,202 adults at least 20 years old, from 3,744 households, 79 provinces and 17 regions. A pre-validated written questionnaire for wheezing among children based on the International Study of Asthma and Allergies of Childhood (ISAAC) was used as the survey instrument. This instrument was adopted since it has been widely used as a case definition for asthma, which allows for comparison of prevalence outcomes across time and population.
RESULTS: The overall prevalence of asthma based on wheezing for the past 12 months was 8.7% (SE 0.4%). Males had a higher prevalence of wheezing for the past 12 months at 9.4% (SE 0.5%) compared to females at 8.2% (SE 0.5%). The overall prevalence of asthma based on wheezing at any time was 14.3% (SE 0.5%). Males had a higher prevalence of wheezing at any time of 14.8% (SE 0.7%) compared to females at 13.8% (SE 0.6%). The prevalence of adult asthma in the rural area was slightly higher than in the urban area (15.3% vs 13.3%), but the difference was not statistically significant.
CONCLUSION: The overall prevalence of adult asthma in the Philippine based on the second NHHeS is 8.7%. This figure is lower than previous reported local prevalence data. The prevalence of adult asthma in the rural and urban setting is almost similar.