This analysis verifies the levels of complementary therapy use among older adults that have been reported in other analyses.1
Other research has evaluated specific complementary therapies; for example, t'ai chi
has shown these therapies to be efficacious in relieving physical symptoms or improving HRQoL among older adults.17,18
However, these evaluations of complementary therapies have had a small number of select participants. Other research evaluating specific complementary therapies in larger samples of older adults (e.g., Gingko biloba
for memory) has not found these therapies to be efficacious.19
This is the first analysis using longitudinal data from a national probability sample to indicate that the use of biologically based therapies predicts better functional status. Evidence on the effectiveness of biologically based therapies is difficult to establish, mainly because many clinical studies of biologically based therapies have barriers such as small sample size, poor design, lack of preliminary dosing data, or difficulty with defining outcomes. Nevertheless, our finding is consistent with previous studies that have yielded positive or at least encouraging data supporting the use of biologically based therapies (e.g., vitamins and minerals) and better functional status.20,21
This analysis also found that the use of manipulative and body-based therapies predicts better functional status, better physical HRQoL, and better mental-health related quality of life. Manipulative and body-based therapies include chiropractic and massage therapy. Our analysis provides new information on the association between the use of manipulative and body-based therapies and better physical and mental HRQoL over a 1-year follow-up period. This is an important finding that has not been reported in the literature before, perhaps because most studies have concentrated on measures of functional status or disability to determine the effectiveness of a manipulative and body-based therapy.22–24
At the same time, we did not find other groups of therapies, alternative medical systems, mind–body therapies, and prayer to be predictive of either functional status or HRQoL. Our study highlights the importance of evaluating multiple outcome measures because different types of complementary therapy actually have specific effects or no effects.
This research has several limitations that should be considered in evaluating the results. Although the number of participants is relative large and they were selected as part of a nationally representative sample, the sample may have limited power to detect some associations given the large number of specific complementary therapies that older adults might use. Biologically based therapies and manipulative and body-based therapies are groups of therapies; we cannot know from these results the specific therapies that may be related to better functional status and HRQoL. In addition, this analysis reports short-term (1 year) effects. Our limited lengths of follow-up leave important questions unanswered about the effects of complementary therapy on long-term health. Interaction effects (e.g., gender by any use of AMS, and ethnicity by any use of MBB) were not included in our analysis, mainly due to low rates of complementary use including AMS, MBB, and MBT. Further stratified analyses (e.g., ethnicity by any use of AMS) would result in small cell sizes and might not have enough power to detect the differences observed across several subgroups. Consideration of interaction effects are possible avenues for future studies. Finally, the results should not be interpreted as evidence for effectiveness of complementary therapies. These findings confirm that randomized trials remain necessary to evaluate the safety and effectiveness of complementary therapy in the health self-management of older adults.
Despite these limitations, the results suggest several important implications. First, older adults turn to complementary therapies because of their potential favorable effects on health. Our findings of the beneficial effects of complementary therapy, although not the same as proof of efficacy, suggest that potential efficacy may be a significant reason for using complementary therapy. These results are consistent with previous studies reporting belief in efficacy as a predictor of use.6
Second, we find selected types (e.g., manipulative and body-based therapies) of complementary therapy to be beneficial not only for functional status but also for physical and mental health-related quality of life. Functional status is necessary for independence, but HRQoL is a particularly important concept for evaluating the health of older adults. HRQoL has been shown to be highly associated with health service utilization and mortality in older adults.25,26
The favorable effects of complementary therapy on HRQoL in a large, national U.S. sample of older adults have not been documented. Furthermore, because of cross-sectional data, previous research has shown an association of poor health or poor HRQoL with complementary therapy use, supporting the notion that poor HRQoL is established before complementary therapy use.3,6,27,28
We recognize HRQoL as an important correlate of complementary therapy use. However, our longitudinal analysis is the first to support the impact of use on HRQoL.
Lastly, the results have an important clinical implication for health professionals who care for aging individuals. Given the prevalence of use and the favorable effects of complementary therapy observed in this analysis, there are reasons to believe that individuals experiencing beneficial effects are likely have a greater commitment to and continue to rely on complementary therapies for health self-management. This may affect the content and quality of patient–provider interaction and adherence to prescribed therapies.29–31
The potential value of complementary therapies should not be discounted. Awareness of the potential benefits can help health providers better monitor and document complementary therapy use in medical charts,32
thus enabling providers to effectively support aging patients in making informed, safe, and appropriate choices.