Health benefits of reduced patient cost sharing in Japan.
OBJECTIVE
To assess the effect on out-of-pocket medical spending and physical and mental health of Japan's reduction in health-care cost sharing from 30% to 10% when people turn 70 years of age.


METHODS
Study data came from a 2007 nationally-representative cross-sectional survey of 10 293 adults aged 64 to 75 years. Physical health was assessed using a 16-point scale based on self-reported data on general health, mobility, self-care, activities of daily living and pain. Mental health was assessed using a 24-point scale based on the Kessler-6 instrument for nonspecific psychological distress. The effect of reduced cost sharing was estimated using a regression discontinuity design.


RESULTS
For adults aged 70 to 75 years whose income made them ineligible for reduced cost sharing, neither out-of-pocket spending nor health outcomes differed from the values expected on the basis of the trend observed in 64- to 69-year-olds. However, for eligible adults aged 70 to 75 years, out-of-pocket spending was significantly lower (P < 0.001) and mental health was significantly better (P < 0.001) than expected. These differences emerged abruptly at the age of 70 years. Moreover, the mental health benefits were similar in individuals who were and were not using health-care services (P = 0.502 for interaction). The improvement in physical health after the age of 70 years in adults eligible for reduced cost-sharing tended to be greater than in non-eligible adults (P = 0.084).


CONCLUSIONS
Reduced cost sharing was associated with lower out-of-pocket medical spending and improved mental health in older Japanese adults.
Department of Society, Human Development and Health, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts, MA 02115, USA. anishi@hsph.harvard.edu
Akihiro
A
Nishi
J Michael
JM
McWilliams
Haruko
H
Noguchi
Hideki
H
Hashimoto
Nanako
N
Tamiya
Ichiro
I
Kawachi
D000203:Activities of Daily Living; D000367:Age Factors; D000368:Aged; D000375:Aging; D017047:Cost Sharing / Q000191:economics / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D003669:Deductibles and Coinsurance / Q000191:economics* / Q000706:statistics & numerical data; D005260:Female; D017048:Health Care Costs; D019538:Health Care Surveys; D006291:Health Policy / Q000191:economics*; D006304:Health Status; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008297:Male; D008603:Mental Health / Q000191:economics* / Q000706:statistics & numerical data; D008875:Middle Aged; D005791:Patient Care / Q000191:economics* / Q000706:statistics & numerical data; D011594:Psychometrics; D012044:Regression Analysis; D057566:Self Report; D013223:Statistics as Topic