Exploring dynamics in catastrophic health care expenditure in Nigeria

BACKGROUND: The Nigeria's National Health Insurance Scheme aimed at making health care accessible and affordable since it's became operational in 2005. However, many Nigerians still pay out of pocket for medical expenses, and this drive them to incurring catastrophic health expenditures. Although monitoring progress towards UHC is crucial, one single study exploring the dynamics in catastrophic health expenditure proportion, associated factors, inequality concentration, inequality size, together with decomposition using a longer period Nigeria panel household survey datasets is very scarce. METHODS: Data was drawn from three rounds of the Nigeria General Household Survey. The fixed percentage and rank-dependent thresholds were used to calculate and compare the proportion of households that incur catastrophic health expenditures. The logistic regression model was employed in analyzing the factors associated with catastrophic health expenditures. The concentration of catastrophic health expenditures inequality was assessed using the concentration curve, whereas the inequality size was determined using the concentration index. The decomposition method was used to decompose the concentration index into determining components. RESULTS: Relative to the fixed threshold value, the rank-dependent threshold revealed a higher share of households facing catastrophic health expenditures i.e., from 27% in 2010/2011 to 48% in 2015/2016. The two thresholds reveal similar trend, but differ in percentage points. The key factors associated with catastrophic health expenditures were economic status and geopolitical zone. Inequality in catastrophic health expenditures was found to be concentrated among the poor. The household economic status was uncovered as the major positive contributor to catastrophic health expenditures inequality across the sample periods. CONCLUSION: The findings of the study imply that narrowing economic status gap across households, and increasing the depth of insurance are crucial mechanisms to reduce the probability of incurring catastrophic health expenditures among the poor in Nigeria.