Out-of-pocket health expenditures and antimicrobial resistance in low-income and middle-income countries: an economic analysis

Abstract

Introduction: The decreasing effectiveness of antimicrobial agents is a growing global public health concern. Low-income and middle-income countries are vulnerable to the loss of antimicrobial efficacy because of their high burden of infectious disease and the cost of treating resistant organisms. We aimed to assess if copayments in the public sector promoted the development of antibiotic resistance by inducing patients to purchase treatment from less well regulated private providers.

Methods: We analysed data from the WHO 2014 Antibacterial Resistance Global Surveillance report. We assessed the importance of out-of-pocket spending and copayment requirements for public sector drugs on the level of bacterial resistance in low-income and middle-income countries, using linear regression to adjust for environmental factors purported to be predictors of resistance, such as sanitation, animal husbandry, and poverty, and other structural components of the health sector. Our outcome variable of interest was the proportion of bacterial isolates tested that showed resistance to a class of antimicrobial agents. In particular, we computed the average proportion of isolates that showed antibiotic resistance for a given bacteria-antibacterial combination in a given country.

Findings: Our sample included 47 countries (23 in Africa, eight in the Americas, three in Europe, eight in the Middle East, three in southeast Asia, and two in the western Pacific). Out-of-pocket health expenditures were the only factor significantly associated with antimicrobial resistance. A ten point increase in the percentage of health expenditures that were out-of-pocket was associated with a 3·2 percentage point increase in resistant isolates (95% CI 1·17-5·15; p=0·002). This association was driven by countries requiring copayments for drugs in the public health sector. Of these countries, moving from the 20th to 80th percentile of out-of-pocket health expenditures was associated with an increase in resistant bacterial isolates from 17·76% (95% CI 12·54-22·97) to 36·27% (31·16-41·38).

Interpretation: Out-of-pocket health expenditures were strongly correlated with antimicrobial resistance in low-income and middle-income countries. This relation was driven by countries that require copayments on drugs in the public sector. Our data suggest cost-sharing of antimicrobials in the public sector might drive demand to the private sector in which supply-side incentives to overprescribe are probably heightened and quality assurance less standardised.

Funding: National Institutes of Health.

Figure 1. Antimicrobial Resistance by Region

Antimicrobial resistance is calculated as the mean over data sources, bacterial-antimicrobial combinations, and over low- and middle-income countries within a given region. See appendix for formula. Source: WHO Antimicrobial resistance global report on surveillance, 2014.

Figure 2

Figure 2a. Out-of-pocket health expenditure (as a percent of private health expenditures) are an important source of health care financing. Source: World Bank, 2012. Figure 2b: Out-of-pocket spending on medications comprises the majority of out-of-pocket health expenditures. Source: WHO World Health Survey, 2003

Figure 2

Figure 2a. Out-of-pocket health expenditure (as a percent of private health expenditures) are an important source of health care financing. Source: World Bank, 2012. Figure 2b: Out-of-pocket spending on medications comprises the majority of out-of-pocket health expenditures. Source: WHO World Health Survey, 2003

Figure 3. Out-of-pocket expenditures (as a % of Total Health Expenditures) predict Antimicrobial Resistance in low- and middle- income countries, 2008–2012

Coefficients are presented from the regression model specified in equation 1. Model estimated as mentioned in the Methods section, adjusts for poverty, livestock, sanitation, hospital bed density, region and bacteria-antimicrobial combination fixed effects. Error bars are 95% CIs based on robust standard errors clustered by country to reflect non-independence of sampling. Sources: World Bank, 2012 & WHO Antimicrobial resistance global report on surveillance, 2014.

Figure 4. Out-of-pocket Health Expenditures (as a percent of Total Health Expenditure) exhibits a dose-response relationship with antimicrobial resistant isolates only in the presence of public sector copayments on medications

The figure plots percent of isolates that demonstrate resistance predicted at the following quintiles of out-of-pocket health expenditure [1=6–20%, 2=21–32%, 3=34–41%, 4=41–49%, 5=50–72%]. The left hand side figure is restricted to the sample of countries requiring a copayment on medications in the public sector (N=23). The right hand side figure is restricted to the sample of countries not requiring a copayment on medications in the public sector (N=24). Sources: World Bank, 2012 & WHO Antimicrobial resistance global report on surveillance, 2014.