Socioeconomic inequalities and trends in self-reported hypertension and antihypertensive medication use in Australia between 2009 and 2021: a nationwide population-based cohort study.

Abstract

This study examined trends in the proportion of adults with self-reported hypertension and in antihypertensive medication use among community-dwelling Australian adults. We analysed data from a longitudinal panel study, covering four waves: 2009 (n = 8023), 2013 (n = 11,475), 2017 (n = 12,843), and 2021 (n = 14,571) for adults aged 18-74 years. Hypertension and antihypertensive medication use were self-reported. Healthcare subsidy was defined as the possession of a low-income healthcare card, a Pensioner Concession Card, or a Commonwealth Seniors Health Card. Prevalence estimates were age-standardised to the 2016 Australian Census population. The age-standardised prevalence of hypertension remained stable from 2009 to 2021, i.e., 15.7% (95% confidence interval [CI]: 15.1-16.4) in 2009 versus 15.2% (95% CI: 14.6-15.7) in 2021. Antihypertensive medication use increased from 39.4% (95% CI: 37.0-41.7) in 2009 to 46.7% (95% CI: 44.0-49.3) in 2021 (P_{for trend}: 0.017). The adjusted prevalence ratios (PR) for hypertension were 1.17 (95% CI: 1.11-1.21) in the 1st (most disadvantaged) Socio-Economic Indexes for Areas (SEIFA) quintiles, compared with the 5th (most advantaged) quintile. The PR for antihypertensive medication use were 1.63 (95% CI: 1.11-1.47) in the 1st quintile compared with the 5th quintile. About 58% to 78% of the increased prevalence of hypertension and antihypertensive medication use related to socioeconomic disadvantage was mediated by healthcare subsidy. The prevalence of hypertension in Australia remained stable between 2009 and 2021. While hypertension drug treatment rates improved over the same period, it remains very low, with less than half of those who reported hypertension receiving antihypertensive medication. Healthcare subsidies improve hypertension detection and treatment, especially in socioeconomically disadvantaged groups.