Multimorbidity worldwide

Multimorbidity, the coexistence of multiple chronic diseases in an individual, increases with age in older adults. Therefore, it is very common that older adults have more than one chronic medical problem at the same time, which impacts treatment for each of the conditions. Multimorbidity is a growing concern worldwide, especially in countries with aging populations. Numerous previous studies have reported that multimorbidity is associated with functional decline (i.e., older adults cannot take care of themselves in some aspects or more), decreased quality of life, and possibly even higher mortality, all of which are of concern to older adults and those who care for them. Aside from the burden on the individual from the conditions, there is also a societal burden from the costs associated with care for these individuals.

Medical and long-term care insurance systems and these expenditures in Japan

Japan has a mandatory universal medical insurance system, established in 1961. It covers services provided by medical professionals (e.g., doctors, nurses, various therapists), diagnostic tests, prescriptions, surgery, and anesthesia. In addition to the universal medical insurance system, Japan also launched a mandatory public long-term care insurance system in 2000. Those aged 65 years and older, as well as those aged between 40 and 64 years with specific aging-related diseases, are eligible for services. These include not only institutional care, whether long-term admission or short-term stay in a long-term care facility, but also community- and home-based care such as adult day care, outpatient rehabilitation, home help, or home-visit nursing. Long-term care insurance is also available in other countries, such as Germany, the Netherlands, and South Korea.

The economic burden on society caused by multimorbidity could be better evaluated by the sum of medical and long-term care expenditures … providing a more-accurate assessment.

A steady increase in health-related spending has been a great concern in countries with aging populations. For example, in Japan in 2016, the annual medical expenditures were approximately US$372 billion and the annual long-term care expenditures were approximately US$88 billion. These figures represent 9% and 21% increases, respectively, over the past 5 years. These expenditures are projected to further increase with a rapidly aging society, both in Japan and around the world.

The associations between multimorbidity and expenditures

In our recent study, we examined the associations between multimorbidity and the sum of medical and long-term care expenditures using medical and long-term care claims data from Kashiwa City, a suburb in the Tokyo metropolitan area, Japan. It was already known that multimorbidity is associated with higher medical expenditures. We found that multimorbidity is also associated with higher long-term care expenditures, thereby increasing the sum of both types of expenditures. Our study further indicated that the economic burden on society caused by multimorbidity could be better evaluated by the sum of medical and long-term care expenditures than by medical expenditures alone, providing a more-accurate assessment.

Japan has one of the most rapidly aging societies in the world and has not only medical but also long-term care insurance systems. As far as we know, this is the first study to examine the associations of multimorbidity with long-term care expenditures and with the sum of medical and long-term care expenditures, worldwide. As the steady increase in health-related spending has been a great threat for maintaining sustainable healthcare systems in many countries with aging populations, our results are meaningful not only for Japan but also globally. Effective strategies for reducing the prevalence of multimorbidity could provide not only medical and functional but also economic benefits for individuals and society.