Does Medication Adherence Lead to Lower Healthcare Expenses for Patients With Diabetes? | Page 5
Published Online: August 13, 2013
Shou-Hsia Cheng, PhD; Chi-Chen Chen, PhD; and Chin-Hsiao Tseng, MD, PhD
It should be noted that the present study has limitations. First, this study did not include some unobserved (such as health literacy) or unavailable characteristics (such as socioeconomic status, severity of illness) in the regression models. Some of these characteristics might influence both medication use and their healthcare outcomes and expenses. For example, patients with a higher education level might be more compliant and would have better healthcare outcomes and lower healthcare expenses, which might result in an overestimation of the effects of medication adherence. Nevertheless, this study employed a longitudinal study design which might account for the unobserved time-invariant characteristics, and this concern might be mitigated. In addition, we included several proxy indicators for severity of illness in the regression models, namely DCSI score, CIC index count, number of physician visits, and hospitalization in the previous year, which might also lessen the bias due to confounders not incorporated in the model. Second, the determination of medication adherence using claims data may have resulted in an overestimation of medication adherence, although MPR calculation based on claims data is a common measure in the literature for quantifying medication adherence.11,12,18-23 Third, due to the lack of information, this study did not incorporate more appropriate outcome measures for diabetes care, such as A1C levels. Finally, there are certain unique aspects of Taiwan’s healthcare system that may make it difficult to generalize the results of this study to other populations.
In conclusion, the findings of this study suggest that adherence to medications can reduce the risk of hospitalizations and ED visits and can lower healthcare expenses for diabetesrelated hospitalizations and ED visits. While patients with better medication adherence still incur higher total healthcare expenses, the adherence-related differences in total healthcare expenses seem to decrease beginning 5 years after the onset of diabetes. The long-term effects of medication adherence deserve further investigation.
Author Affiliations: From Institute of Health Policy and Management (S-HC, C-CC), College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Internal Medicine (C-HT), National Taiwan University College of Medicine, Taipei, Taiwan; Division of Endocrinology and Metabolism (C-HT), Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Funding Source: None.
Author Disclosures: The authors (S-HC, C-CC, C-HT) report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.
Authorship Information: Concept and design (S-HC); acquisition of data(S-HC); analysis and interpretation of data (S-HC, C-CC, C-HT); drafting of the manuscript (S-HC); critical revision of the manuscript for important intellectual content (S-HC, C-HT); statistical analysis (C-CC); obtaining funding (S-HC); and supervision (S-HC).
Address correspondence to: Shou-Hsia Cheng, PhD, Institute of Health Policy and Management, College of Public Health, National Taiwan University, 17, Xu-Zhou Rd, Taipei, Taiwan, 100. E-mail: email@example.com.
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