Income-based differences in health care utilization in relation to mortality: Trends in the Swedish population between 2004-2017

BackgroundDespite universal health care, socioeconomic differences in health care utilization (HCU) persist in modern welfare states. The aim of this study is to assess income-based differences in utilization of primary- and specialized care in relation to mortality for the Swedish general population (>15 years old) between 2004 and 2017. Methods and FindingsUsing a repeated cross-sectional register-based study design, data on utilization of i) primary-ii) specialized outpatient- and iii) inpatient care, as well as iv) cause of death, were linked to family income and sociodemographic control variables. HCU and mortality for all-disease as well as for the five disease groups causing most deaths were compared for the lowest (Q1) and highest (Q5) income quintile using logistic regression. We also analysed income-related differences in the number of health care encounters [≤]5 years prior to death. In 2017, for all diseases combined, Q1 utilized marginally more primary- and specialized outpatient care than Q5 (adjusted odds ratio [OR] =1.07, 95% CI: 1.07, 1.08; OR 1.04, 95% CI: 1.04, 1.05, respectively), and considerably more inpatient care (OR=1.44, 95% CI: 1.43, 1.45). The largest relative inequality was observed for mortality (OR 1.78, 95% CI: 1.74, 1.82). This pattern was broadly reproduced for each of the five diseases. Time trends in HCU inequality varied by level of care. Each year, Q1 (vs. Q5) used more inpatient care and suffered increasing mortality rates. However, usage of primary- and specialized outpatient care increased more among Q5 than in Q1. Finally, Q1 and Q5 had similar number of encounters in primary- and inpatient care [≤]5 years prior to death, but Q1 had significantly fewer outpatient encounters. ConclusionsIncome-related differences in the utilization of primary and specialized outpatient care were considerably smaller than for mortality, and this discrepancy widened with time. Facilitating motivated use of primary- and outpatient care among low-income groups could help mitigate the growing health inequalities.