When good knowledge falls short: identity and geography drive inappropriate antibiotic use in Malaysia

Inappropriate antibiotic use has been associated with poor knowledge on antibiotic use. However, behavioural change interventions targeting knowledge alone have low efficacy. Such a paradox warranted this pioneer study to determine the factors associated with inappropriate antibiotic use among the general population in Malaysia, particularly among those with good knowledge.

This was a cross-sectional survey conducted in 2020 on community-dwelling populations aged ≥ 15 years in Malaysia. They were selected using a two-stage stratified random cluster sampling design to represent the general population. Data were collected through face-to-face and computer-assisted telephone interviews. Antibiotic use for common cold or sore throat in the past one year was defined as inappropriate. This outcome was tested for association with the exposure variables, namely sociodemographic characteristics and knowledge score on antibiotic use, using the survey-weighted logistic regression function in STATA version 18.

A total of 3,051 people participated, representing an estimated 24.6 million population in Malaysia. Among the overall population, the odds for inappropriate antibiotic use were higher among those with lower knowledge scores (aOR 2.381, 95%CI 1.365-4.153, p = 0.003, vs. higher scores) and younger age groups (aOR 3.727, 95%CI 2.040-6.807 for 15-17 years and 2.256, 95%CI 1.466-3.471 for 18-59 years, both p < 0.001, vs. ≥ 60 years), but lower among foreigners/non-citizens (aOR 0.468, 95%CI 0.266-0.822, p = 0.009, vs. native/bumiputera Malaysians). However, in the subgroup analysis among those with higher knowledge scores only, the odds were lower among non-native/non-bumiputera Malaysians (aOR 0.147, 95%CI 0.033-0.650, p = 0.012, vs. native/bumiputera) and those from peninsular states outside the central region (aOR 0.140, 95%CI 0.047-0.419, p = 0.001, vs. central).

Interventions to reduce inappropriate antibiotic use should focus on increasing population knowledge generally with more emphasis on individuals aged < 60 years. However, among those who already have good knowledge, the interventions should also enable individuals to overcome the obstacles to the desirable behaviours, especially among native/bumiputera Malaysians and those living in the central region.