Longitudinal Analysis of Complementary Health Approaches in Adults Aged 25-74 Years from the Midlife in the U.S. Survey Sample.

Objectives: Complementary health approaches include herbal products and mind-body practices. Several studies have identified predictors for complementary health approach use, yet there are two gaps: (1) How does use change? (2) Do factors associated with use influence this change over time? Using the Midlife in the United States (MIDUS), we examined how sociodemographic factors affected use longitudinally, and whether these associations differed between new and continued/discontinued use of herbal products, meditation, chiropractic, and massage therapy. Design: MIDUS is a national probability sample of adults aged 25 or older that has collected more than 20 years of longitudinal data, including the use of complementary health approaches. We employed the Andersen Model as a framework to identify predisposing, enabling, and health need factors associated with complementary health approach use based on previously identified and hypothesized factors. We ran Chi-square analyses to first test bivariate associations between our independent variables and four modalities to further guide logistic regression models. Results: Each of the four approaches examined saw substantial increases in prevalent use. However, only about 25% to 38% of individuals continued use from one wave to the next, whereas only 2%-9% of individuals who did not use a given approach in a wave reported use in the subsequent wave. Age, spiritual importance, and previous wave one use were all significantly associated with new use across all four modalities. Previous wave one use was associated with continued/discontinued use for all modalities. Age and education were significantly associated with discontinued use of chiropractic. Conclusion: We present the first longitudinal analysis of complementary health approaches in a nationally representative sample. These data distinguish between new and continued/discontinued use of complementary health approaches over time and provide insights into the interpretation of complementary health approach prevalence data, as well as important predictors of use.