Association between recorded medical diagnoses and incidence of long-term care needs certification: a case control study using linked medical and long-term care data in two Japanese cities

抄録

BACKGROUND

It is unknown which medical diagnoses are strongly associated with long-term care needs certification.

METHODS

We conducted a case-control study using linked medical and long-term care data from two Japanese cities. The participants were aged ≥75 years, without any previous long-term care needs certification, and had at least one medical insurance claim record during a period between April 2013 and March 2015 in City A and between April 2013 and November 2016 in City B. Cases were newly certified people for long-term care needs during the study period, whereas controls (matched on age category, sex, city, and calendar date) were randomly selected in a 1:4 ratio. We conducted multivariable conditional logistic regression analyses to estimate the association between 22 categories of medical diagnoses recorded in the past six months and new (i.e., first ever) long-term care needs certification.

RESULTS

Among 38,338 eligible people, 5,434 (14.2%) newly received long-term care needs certification. The adjusted odds ratio (95% confidence interval) was largest for femur fractures, 8.80 (6.35–12.20), followed by dementia, 6.70 (5.96–7.53), pneumonia, 3.72 (3.19–4.32), hemorrhagic stroke, 3.31 (2.53–4.34), Parkinson’s disease, 2.74 (2.07–3.63), and other fractures, 2.68 (2.38–3.02). A restricted analysis to more severe outcome (care need levels 2 to 5), sensitivity analysis to use different periods for exposure definition, and separate analysis by city showed consistent results.

CONCLUSIONS

Among a range of recorded medical diagnoses, fractures (especially femur fractures), dementia, pneumonia, hemorrhagic stroke, and Parkinson’s disease were strongly associated with long-term care needs certification.