Prediction of Future Burden of Diseases in Japan

Data on the burden of every disease is vital to prioritize healthcare policies. In addition to data pertaining to the current situation, an estimate of the future burden of diseases is also important for formulating future policies. The objective of the present study was to provide data to formulate healthcare policies. We used a regression model and statistical data from the government to estimate the number of patients and deaths for each disease. We found that for the years 2010, 2020, and 2030, the estimated number of total deaths is 1.16 million, 1.34 million, and 1.42 million, respectively, and the percentage of deaths for those ≥ 85 years of age was 38%, 51%, and 59%, respectively, predicting a marked increase over the next few decades. The estimated leading causes of disease-related deaths in the future were neoplasms, cardiovascular disease, and respiratory disease, in that order, as was the case in 2005. A large increase was estimated in both men and women for neoplasms and respiratory diseases. In contrast, cardiovascular disease estimates remained relatively constant, as cardiac disorder increased but cerebrovascular disease decreased. The estimated number of total patients in 2005 was 42.73 million. The estimated total number of patients in 2010, 2020, and 2030 were 44.17 million, 45.56 million, and 44.80 million, respectively. Percentages of patients ≥ 65 years of age from 2005 were 40%, 44%, 53%, and 56%, respectively. Diseases for which the estimated number of patients increased from 2005 to 2030 based on data from patient surveys included infectious diseases (32% increase), tracheal/bronchial/lung cancer (98% increase), diabetes (38% increase), dementia (105% increase), schizophrenia (32% increase), nervous system disorders (138% increase), high blood pressure (25% increase), pneumonia (210% increase), spinal disorders (51% increase), kidney dysfunction (51% increase), and prostate enlargement (111% increase). On the other hand, the estimated number of patients for some diseases decreased, including that for stomach cancer (58% decrease), ischemic cardiac disease (67% decrease), and cerebrovascular disease (49% decrease). The estimated number of patients by disease based on the outpatient rate of the Survey of National Living Standards largely outnumbered that which was based on patient surveys. Estimates based on outpatient rates for diabetes, dementia, high blood pressure, and cerebrovascular disease were 2-3 times greater than those based on patient surveys, while estimates for angina and cardiac infarction were 4-10 times higher. This large variability in estimates may be due to the fact that many patients may not complete treatment or may postpone treatment, or that the mean treatment period used to estimate the number of patients may not be entirely accurate.