Risk factors of self-reported adverse drug events among Medicare enrollees before and after Medicare Part D
Objectives: Quantify risk factors for self-reported adverse drug events (ADEs) after the implementation of Medicare Part D, quantify self-reported ADEs before and after Medicare Part D and quantify the association between self-reported ADEs and increased use of prescription medication.
Methods: The design was a longitudinal study including an internet survey before Medicare Part D in 2005 (n=1220) and a follow-up survey in 2007 (n=1024), with n=436 responding to both surveys. Harris Interactive® invited individuals in their online panel to participate in this study. Individuals who were 65 or older, English speakers, US residents and enrolled in Medicare were included. Data collected and used in analysis included self-reported ADE, socio-demographics, self-rated health, number of medications, symptoms experienced, concern and necessity beliefs about medicines, number of pharmacies, and whether doses were skipped or stopped to save money.
Results: In 2007, reporting an ADE was related to concern beliefs, symptoms experienced and age. ADEs were experienced by 18% of respondents in 2005 and 20.4% in 2007. The average number of medications increased from 3.82 (SD=2.82) in 2005 to 4.32 (SD=3.20) in 2007 (t= -5.77, p<0.001). Among respondents who answered both surveys (n=436), 18.4% reported an ADE in 2005 while 24.3% reported an ADE in 2007. The increase in self-reported ADE was related to concern beliefs (OR=1.12, 95%CI=1.05, 1.19) and symptoms experienced (OR= 3.27, 95%CI=1.60, 6.69), not number of medications (OR=1.04, 95%CI=0.77, 1.41).
Conclusion: Discussing elderly patients’ beliefs about their medicines may affect their medication expectations, symptom interpretation and attributions and future medication attributions.
2. Gandhi TK, Weingart SN, Borus J, Seger AC, Peterson J, Burdick E, Seger DL, Shu K, Federico F, Leape LL, Bates DW. Adverse drug events in ambulatory care. N Eng J Med. 2003;348:1556-1564.
3. Weingart SN, Gandhi TK, Seger AC, Seger D, Borus J, Burdick E, Leape LL, Bates DW. Patient-reported medication symptoms in primary care. Arch Intern Med. 2005;165:234-240.
4. Budnitz DS, Pollock DA, Wiedenbach KN, Mendelsohn AB, Schroeder TJ, Annest JL. National surveillance of emergency department visits for outpatient adverse drug events. JAMA. 2006;296:1858-1866.
5. Bates DW, Cullen DJ, Laird N, Petersen LA, Small SD, Servi D, Laffel G, Sweitzer BJ, Shea BF, Hallisey R, Vander Vilet M, Nemeskal R, Leape LL. Incidence of adverse drug events and potential adverse drug events: implications for prevention. JAMA. 1995;274:29-34.
6. Institute of Medicine., Preventing medication errors (Washington DC: National academy press, 2006).
7. Bates DW, Boyle DL, Vander Vliet MB, Schneider J, Leape L. Relationship between medication errors and adverse drug events. J Gen Intern Med. 1995;10:199-205.
8. Caterino JM, Emond JA, Carmago CA. Inappropriate medication administration to the acutely ill elderly: a nationwide emergency department study, 1992-2000. J Am Geriatr Soc. 2004;52:1847-1855.
9. Curtis LH, Ostbye T, Sendersky V, Hutchison S, Dans PE, Wright A, Woosley RL, Schulman KA. Inappropriate prescribing for elderly Americans in a large outpatient population. Arch Intern Med. 2004;164:1621-1625.
10. Higashi T, Shekelle PG, Solomon DH, Knight EL, Roth C, Chang JT, Kamberg CJ, MacLean CH, Young RT, Adams J, Reuben DB, Avorn J, Wenger NS. The quality of pharmacology care for vulnerable older patients. Ann Intern Med. 2004;104:714-720.
11. Zhan C, Correa-de-Araujo R, Bierman AS, Snagl J, Miller MR, Wickizer SW, Stryer D. Suboptimal prescribing in elderly outpatients: potentially harmful drug-drug and drug-disease combinations. J Am Geriatr Soc. 2005;53:262-267.
12. Jano E, Aparasu RR. Healthcare outcomes associated with beers’ criteria: a systematic review. Ann Pharmacother 2007;41:438-448. DOI 10.1345/aph.1H473.
13. Green JL, Hawley JN, Rask JL. Is the number of prescribing physicians an independent risk factor for adverse drug event in an elderly outpatient population?. Am J Geriatr Pharmacother. 2007;5(1):31-39. doi:10.1016/j.amjopharm.2007.03.004
14. Chrischilles EA, Segar ET, Wallace RB. Self-reported adverse drug reactions and related resource use. Ann Intern Med. 1992;117:634-640.
15. Evans RS, Lloyd JF, Stoddard GJ, Nebeker JR, Samore M. Risk factors for adverse drug events: a 10-year analysis. Ann Pharmacother. 2005;39:1116-1118. DOI 10.1345/aph.1E642.
16. Dewitt JE, Sorofman BA. A model for understanding patient attribution of adverse drug reaction symptoms. Drug Inf J. 1999;33:907-920.
17. Liu GG, Christensen DB. The continuing challenge of inappropriate prescribing in the elderly: an update of the evidence. J Am Pharm Assoc. 2002;42:847-857.
18. Oladimeji OO, Farris KB, Urmie JG, Doucette WR. Risk factors for self-reported adverse drug events among Medicare enrollees. Ann Pharmacother. 2008;42;53-61. DOI 10.1345/aph.1K073
19. Horne R, Weinman J, Hankins M. The Beliefs about medicines questionnaire: The development and evaluation of a new method for assessing the cognitive representation of medication. Psychol Health. 1999;14:1-24.
20. Horne R, Weinman J. Patients beliefs about prescribed medicines and their role in adherence to treatment in chronic physical illness. J Psychosom Res. 1999;47(6):555-67.
21. Evans-Molina C, Regan S, Henault LE, Hylek EM, Schwartz GR. The new Medicare Part D prescription drug benefit: an estimation of its effect on prescription drug costs in a Medicare population with atrial fibrillation. J Am Geriatr Soc. 2007 Jul;55(7):1038-1043.
22. Lichtenberg FR, Sun SX. The impact of Medicare Part D on prescription drug use by the elderly. Health Aff (Millwood).. 2007;26(6):1735-1744. DOI 10.1377/hlthaff.26.6.1735
23. Pauly M. Medicare drug coverage and moral hazard. Health Aff (Millwood). 2004;23(1):113-122.
24. Karaca Z, Streeter SB, Barton V, Nguyen K, Norris K. The impact of Medicare Part D on beneficiaries with type 2 diabetes/drug utilization and out-of-pocket costs. Available at http://ssrn.com/abstract=1109130 (Accessed June 7, 2008).
25. Neuman P, Strollo MK, Guterman S, Rogers WH, Li A, Rodday AM, Safran DG. Medicare prescription drug benefit progress report: findings from a 2006 national survey of seniors. Health Aff (Millwood). 2007;26(5):w630-643. DOI 10.1377/hlthaff.26.5.w630
26. The Amundsen group, September 2007. Medicare Part D: Assessing the impact for beneficiaries without previous drug coverage and dual eligibles. Available at: www. amundsengroup.com (Accessed June 7, 2008).
27. Yin W, Basu A, Zhang J, Rabbani A, Meltzer D, Alexander C. The effect of the Medicare Part D prescription benefit on drug utilization and expenditures. Ann Intern Med. 2008;148:169-177.
28. Idler EL, Benyamini Y. Self-rated health and mortality: A review of twenty-seven community studies. J Health Soc Behav. 1997;38(1):21-37.
29. Bailis DS, Segall A, Chipperfield JG. Two views of self-rated health status. Soc Sci Med. 2003;56:203-217.
30. Chrischilles E, Rubenstein L, Van Gilder R, Voelker M, Wright K, Wallace R. Risk factors for adverse drug events in older adults with mobility limitations in the community setting. J Am Geriatr Soc. 2007;55:29-34.
31. Piecoro LT, Browning SR, Prince TS, Ranz TT, Scutchfield FD. A database analysis of potentially inappropriate drug use in an elderly Medicaid population. Pharmacotherapy. 2000;20:221-228.
32. Hanlon JT, Schmader KE, Koronkowski MJ, Weinberger M, Landsman PB, Samsa GP, Lewis IK. Adverse drug events in high risk older outpatients. J Am Geriatr Soc. 1997;45:945-948.
33. Bond CA, Raehl CL, Franke T. Clinical pharmacy services, hospital pharmacy staffing, and medication errors in United States hospitals. Pharmacotherapy. 2002;22(2):134-147.
34. Kucukarsian SN, Peters M, Mlynarek M, Nafziger DA. Pharmacists on rounding teams reduce preventable adverse drug events in hospital general medicine units. Arch Intern Med. 2003;163:2014-2018.
35. LaPointe NM, Jollis JG. Medication errors in hospitalized cardiovascular patients. Arch Intern Med. 2003;163:1461-1466.
36. Schnipper JL, Kirwin J, Cotugno MC, Wahlstrom SA, Brown BA, Tarvin E, Kachalia A, Horng M, Roy CL, McKean SC, Bates DW. Role of pharmacist counseling in preventing adverse drug events after hospitalization. Arch Intern Med. 2006;166:565-571.
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