Multimorbidity adjusted years lost to disability rates calculated through Monte-Carlo simulation in Korea

OBJECTIVES: To efficiently utilize limited health and medical resources, it is necessary to accurately measure the level of health, which requires estimating the multimorbidity-corrected burden of disease. METHODS: This study used 2015 and 2016 data from the National Health Insurance Service, and employed the list of diseases defined in a Korean study of the burden of disease, the criteria for prevalence, and the "cause-sequelae-health state"disease system. When calculating the years lost to disability (YLD), multimorbidity was corrected using Monte-Carlo simulation. RESULTS: Correcting for multimorbidity changed YLD at all ages in Korea by -1.2% (95% confidence interval [CI], -24.1 to 3.6) in males and -12.4% (95% CI, -23.0 to 0.3) in females in 2015, and by -10.8% (95% CI, -24.1 to 4.6) in males and -11.1% (95% CI, -22.8 to 1.7) in females in 2016. The YLD rate for non-communicable diseases in males decreased more than that of other disease groups in both years, by -11.8% (95% CI, -19.5 to 3.6) and -11.5% (95% CI, -19.3 to -3.0), respectively. The overall YLD rate changed by -1.3% in the 5-year to 9-year age group, and the magnitude of this change remained similar until the 10-19-year age group, gradually decreased after 20 years of age, and steeply increased to more than 10% in those aged 60 and older. CONCLUSIONS: Calculations of YLD should adjust for multimorbidity, as the disease burden can otherwise be overestimated for the elderly, who tend to exhibit a high prevalence of multimorbidity.