Background: One of the criteria for measuring the performance of governments and their survival is the degree of success in reducing and stabilizing the misery index. The misery index is obtained from the sum of inflation and unemployment. Inflation and unemployment are the most important factors affecting family's income. If the misery index is high, families will have less money to buy their consumer goods, including the use of healthcare services and treatment. Therefore, this research has evaluated the relationship between misery index and patients' out-of-pocket payments in Iran's health system.
 Methods: Using time series data of 1998-2019, this study has investigated the relationship between misery index and patients' out-of-pocket payments in Iran's health system. For this purpose, the Dickey-Fuller test was used to check the durability of the variables, the Todayamamoto causality test was used to check the causality relationship between the variables, and the autoregression method with distribution breaks was used to check the existence of a long-term relationship. In addition, the data and results were analyzed using Eview 9 software.
 Results: The results showed that there was a bi-directional causal relationship between the misery index and the out-of-pocket payments of patients in the health system. Furthermore, with increasing 1 unit of misery index 1.27 units of out-of-pocket payments increased. The correction error coefficient was 0.312, which meant this amount was adjusted each period by 0.312 from short-term imbalance to achieve long-term balance. In other words, it takes more than 3 years and less than 4 years to eliminate the short-term imbalances and reach its long-term relationship.
 Conclusion: As the misery index increases, patients' out-of-pocket payments also increase. Therefore, the government should reduce the out-of-pocket payments of patients in the health system by adopting appropriate policies to reduce unemployment and inflation. Basic insurance coverage for essential services for patients should be increased. The extent of complementary medical insurance should be increased at the community level, especially in the lower deciles. In fact, the government should bear the cost of this part of the insurance for the four lower deciles. This is done in order to reduce the patients' out-of-pocket payments.