BACKGROUND: Non-adherence to cardiovascular medications is a problem worldwide, even in Australia, which has a socialized medical system, Medicare.
OBJECTIVE: The aim of this systematic review was to evaluate the burden of non-adherence to cardiovascular medications and factors thereof in Australia.
DATA SOURCES: Pubmed, Embase, CINAHL, PsycInfo, Cochrane Library databases were searched.
ELIGIBILITY CRITERIA: Articles were included if they were in English, peer-reviewed and provided empirical data on adherence to cardiovascular medication for an Australian cohort.
METHODS: A meta-analysis of prevalence of medication non-adherence using the double arcsine square root transformed proportion was undertaken. Studies were pooled in homogenous prevalence groups and factors that differed across groups were ascertained.
RESULTS: Five studies, including eight datasets and 76,867 subjects were analyzed. Three more or less homogenous prevalence categories were discernable: low [19 %, 95 % confidence interval (CI) 15-24], moderate (26 %, 95 % CI 23-29) and high (43 %, 95 % CI 43-44; this was a single study) prevalence of non-adherence. There were minimal clear patterns across groups in relation to typical factors of non-adherence (patient, condition, healthcare system or socioeconomic factors). Measurements used for non-adherence were similar for six of the eight included datasets, suggesting this did not affect prevalence of non-adherence or inclusion in a prevalence group.
CONCLUSIONS: Non-adherence to cardiovascular medications is a serious problem in the aging Australian setting with an overall prevalence of between 14 and 43 %. The lack of patterns in the typical factors of non-adherence suggests that another factor, such as patients' beliefs about their conditions and medications, may be playing a stronger role in their non-adherence than clinical or sociodemographic factors. This is an area for further research.