Determinants of adherence to diabetes medications: findings from a large pharmacy claims database

M Sue Kirkman, Megan T Rowan-Martin, Rebecca Levin, Vivian A Fonseca, Julie A Schmittdiel, William H Herman, Ronald E Aubert, M Sue Kirkman, Megan T Rowan-Martin, Rebecca Levin, Vivian A Fonseca, Julie A Schmittdiel, William H Herman, Ronald E Aubert

Abstract

Objective: Adults with diabetes typically take multiple medications for hyperglycemia, diabetes-associated conditions, and other comorbidities. Medication adherence is associated with improved outcomes, including reduced health care costs, hospitalization, and mortality. We conducted a retrospective analysis of a large pharmacy claims database to examine patient, medication, and prescriber factors associated with adherence to antidiabetic medications.

Research design and methods: We extracted data on a cohort of >200,000 patients who were treated for diabetes with noninsulin medications in the second half of 2010 and had continuous prescription benefits eligibility through 2011. Adherence was defined as a medication possession ratio ≥ 0.8. We used a modified adherence measure that accounted for switching therapies. Logistic regression analysis was performed to determine factors independently associated with adherence.

Results: Sixty-nine percent of patients were adherent. Adherence was independently associated with older age, male sex, higher education, higher income, use of mail order versus retail pharmacies, primary care versus nonendocrinology specialist prescribers, higher daily total pill burden, and lower out-of-pocket costs. Patients who were new to diabetes therapy were significantly less likely to be adherent.

Conclusions: Several demographic, clinical, and potentially modifiable system-level factors were associated with adherence to antidiabetic medications. Patients typically perceived to be healthy (those who are younger, new to diabetes, and on few other medications) may be at risk for nonadherence. For all patients, efforts to reduce out-of-pocket costs and encourage use of mail order pharmacies may result in higher adherence.

© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

References

    1. Asche C, LaFleur J, Conner C. A review of diabetes treatment adherence and the association with clinical and economic outcomes. Clin Ther 2011;33:74–109
    1. Pladevall M, Williams LK, Potts LA, Divine G, Xi H, Lafata JE. Clinical outcomes and adherence to medications measured by claims data in patients with diabetes. Diabetes Care 2004;27:2800–2805
    1. Ho PM, Magid DJ, Masoudi FA, McClure DL, Rumsfeld JS. Adherence to cardioprotective medications and mortality among patients with diabetes and ischemic heart disease. BMC Cardiovasc Disord 2006;6:48.
    1. Bogner HR, de Vries HF, O’Donnell AJ, Morales KH. Measuring concurrent oral hypoglycemic and antidepressant adherence and clinical outcomes. Am J Manag Care 2013;19:e85–e92
    1. Sokol MC, McGuigan KA, Verbrugge RR, Epstein RS. Impact of medication adherence on hospitalization risk and healthcare cost. Med Care 2005;43:521–530
    1. Juarez DT, Tan C, Davis J, Mau M. Factors affecting sustained medication adherence and its impact on health care utilization in patients with diabetes. J Pharm Health Serv Res 2013;4:89–94
    1. Hong JS, Kang HC. Relationship between oral antihyperglycemic medication adherence and hospitalization, mortality, and healthcare costs in adult ambulatory care patients with type 2 diabetes in South Korea. Med Care 2011;49:378–384
    1. Breitscheidel L, Stamenitis S, Dippel F-W, Schöffski O. Economic impact of compliance to treatment with antidiabetes medication in type 2 diabetes mellitus: a review paper. J Med Econ 2010;13:8–15
    1. Hansen RA, Farley JF, Droege M, Maciejewski ML. A retrospective cohort study of economic outcomes and adherence to monotherapy with metformin, pioglitazone, or a sulfonylurea among patients with type 2 diabetes mellitus in the United States from 2003 to 2005. Clin Ther 2010;32:1308–1319
    1. Cramer JA. A systematic review of adherence with medications for diabetes. Diabetes Care 2004;27:1218–1224
    1. Peterson AM, Nau DP, Cramer JA, Benner J, Gwadry-Sridhar F, Nichol M. A checklist for medication compliance and persistence studies using retrospective databases. Value Health 2007;10:3–12
    1. Hess LM, Raebel MA, Conner DA, Malone DC. Measurement of adherence in pharmacy administrative databases: a proposal for standard definitions and preferred measures. Ann Pharmacother 2006;40:1280–1288
    1. Karve S, Cleves MA, Helm M, Hudson TJ, West DS, Martin BC. Good and poor adherence: optimal cut-point for adherence measures using administrative claims data. Curr Med Res Opin 2009;25:2303–2310
    1. SAS Institute Inc Base SAS 9.3. Cary, NC, SAS Institute Inc., 2011
    1. Rolnick SJ, Pawloski PA, Hedblom BD, Asche SE, Bruzek RJ. Patient characteristics associated with medication adherence. Clin Med Res 2013;11:54–65
    1. Guénette L, Moisan J, Breton M-C, Sirois C, Grégoire J-P. Difficulty adhering to antidiabetic treatment: factors associated with persistence and compliance. Diabetes Metab 2013;39:250–257
    1. Rodriguez F, Cannon CP, Steg PG, et al. .; REACH Registry Investigators . Predictors of long-term adherence to evidence-based cardiovascular disease medications in outpatients with stable atherothrombotic disease: findings from the REACH Registry. Clin Cardiol 2013;36:721–727
    1. Choudhry NK, Glynn RJ, Avorn J, et al. Untangling the relationship between medication adherence and post-myocardial infarction outcomes: medication adherence and clinical outcomes. Am Heart J 2014;167:51.e5–58.e5
    1. Manteuffel M, Williams S, Chen W, Verbrugge RR, Pittman DG, Steinkellner A. Influence of patient sex and 4 on medication use, adherence, and prescribing alignment with guidelines. J Womens Health (Larchmt) 2014;112–119
    1. van Bruggen R, Gorter K, Stolk RP, Zuithoff P, Klungel OH, Rutten GEHM. Refill adherence and polypharmacy among patients with type 2 diabetes in general practice. Pharmacoepidemiol Drug Saf 2009;18:983–991
    1. Schmittdiel JA, Karter AJ, Dyer W, et al. . The comparative effectiveness of mail order pharmacy use vs. local pharmacy use on LDL-C control in new statin users. J Gen Intern Med 2011;26:1396–1402
    1. Duru OK, Schmittdiel JA, Dyer WT, et al. . Mail-order pharmacy use and adherence to diabetes-related medications. Am J Manag Care 2010;16:33–40
    1. Sharma KP, Taylor TN. Pharmacy effect on adherence to antidiabetic medications. Med Care 2012;50:685–691
    1. Curkendall SM, Thomas N, Bell KF, Juneau PL, Weiss AJ. Predictors of medication adherence in patients with type 2 diabetes mellitus. Curr Med Res Opin 2013;29:1275–1286
    1. Iyengar RN, Balagere DS, Henderson RR, LeFrancois AL, Rabbitt RM, Frazee SG. Association between dispensing channel and medication adherence among medicare beneficiaries taking medications to treat diabetes, high blood pressure, or high blood cholesterol. J Manag Care Pharm 2014;20:851–861
    1. Ellis JJ, Erickson SR, Stevenson JG, Bernstein SJ, Stiles RA, Fendrick AM. Suboptimal statin adherence and discontinuation in primary and secondary prevention populations. J Gen Intern Med 2004;19:638–645
    1. Tseng C-W, Tierney EF, Gerzoff RB, et al. . Race/ethnicity and economic differences in cost-related medication underuse among insured adults with diabetes: the Translating Research Into Action for Diabetes Study. Diabetes Care 2008;31:261–266
    1. Chen CC, Tseng CH, Cheng SH. Continuity of care, medication adherence, and health care outcomes among patients with newly diagnosed type 2 diabetes: a longitudinal analysis. Med Care 2013;51:231–237
    1. Shrank WH, Choudhry NK, Fischer MA, et al. . The epidemiology of prescriptions abandoned at the pharmacy. Ann Intern Med 2010;153:633–640

Source: PubMed

Sponsorer och medarbetare

Medicinska tillstånd

Läkemedelsinterventioner

3
Prenumerera