Age Variations in the Predictors and Consequence of Health Service Use using the Korean Longitudinal Study on Aging (KLOSA)

Purpose: Korean government launched “Korean Longitudinal Study on Aging (KLOSA)” in the year of 2006, collecting data in every two years. KLOSA is similar to the Health and Retirement Study and is the first nationally representative data on Korean middle and old aged adults. Anderson Model posits that predisposing factors, enabling factors, and need factors are associated with health services use and its consequences. However, little is known about whether health service use patterns vary depending on age, which would provide social workers with implications for age sensitive health services and prevention strategies. Using KLOSA, this study aims to answer following two questions - (1) What are the predictors and consequences of health service uses? (2) Are there age variations in the mechanisms between middle and old aged adults (i.e., less than 65 vs. over 65)?

Methods: Samples consist of 10,254 adults aged 45 and over who participated in the first wave of KLOSA. KLOSA used stratified probability sampling methods and data were collected through fact-to-face interviews. Following the propositions of the Andersen Model, this study first examines the predictors and consequence of health behaviors using Structural Equation Modeling (SEM). Predisposing predictors include age, gender, and education. Enabling predictors include income, informal social networks, and formal social networks. Need predictors include chronic health conditions and pains. Mediating variables were health service uses, including days in a hospital (inpatient services) and numbers of doctor visits (outpatient services). Consequence variable was depression. This study then examines whether there are age variations in the predictors and consequences of health service use using multi-group SEM. All fit index indicate that the SEM fits the data well (IFI & CFI > .90 and RMSEA < .05).

Results: Results indicate that outpatient health service uses are correlated with age(+) and chronic health conditions(+); it was interesting to find that inpatient service uses are correlated with no predictor variable. Although all hypothesized predictor variables are significantly associated with the consequence variable of depression, the hypothesized mediating variables of inpatient and outpatient health service use variables are not associated with depression.

In order to examine possible moderating roles of age in the mechanisms, this study performs multi-group SEM. Outpatient service uses are significantly associated with age(+) and chronic health conditions(+) only for those 65 and over. Inpatient service uses are significantly associated with gender(male+), informal social networks(-), chronic health conditions(+), and pains(+) only for those under 65. Depression is significantly associated with both inpatient(+) and outpatient(+) service use for those under 65; however, no health service use is significantly associated with depression for those 65 and over.

Implications: The results indicate that there are significant age variations in the patterns of health services use and its consequences, indicating that it is necessary for social workers to consider these age variations in developing intervention and prevention strategies concerning health service uses for middle and old aged people. The paper discusses the meaning of findings, the findings of meditational paths and implications for future research and practice.