Main Article Content
Medication Adherence, Prevalence, Causality, Multivariate Analysis, Lebanon
Background: Non-adherence to prescribed medications represents an obstacle toward achieving treatment goals. This problem is more pronounced in patients with chronic illness.
Objective: To identify the extent of adherence in Lebanese outpatients with chronic diseases, and to suggest possible predictors of non-adherence in this population. The secondary objective was to assess if medication adherence affects patients' quality of life.
Methods: A questionnaire was administered face-to-face to a sample of Lebanese adults visiting the external clinics at two Tertiary Care Hospitals in Beirut. The level of adherence was assessed using the 8-item Morisky Medication Adherence Scale which was first validated. The health-related quality of life (HRQoL) of patients was measured using the EQ-5D. Linear regression and logistic regression analyses examined possible predictors of adherence.
Results: Out of the 148 patients included in this study, 42.6% were classified as adherent. In the univariate analyses, statistically significant predictors of high adherence included good physician-patient relationship (p=0.029) and counseling (p=0.037), a high level of HRQoL (p<0.001), and a high level of perceived health (p<0.001). Predictors of low adherence included a declining memory (p<0.001), anxiety/depression (p=0.002), little drug knowledge (p<0.001), and postponing physician appointments (p<0.001). The multivariate analyses revealed similar results. In the linear regression, the most powerful predictor of non-adherence was the disbelief that the drug is ameliorating the disease (beta=0.279), however, in logistic regression, patient who were willing to skip or double doses in case of amelioration/deterioration were found to be 7.35 times more likely to be non-adherent than those who were not (aOR=0.136, 95%CI: 0.037-0.503).
Conclusion: The findings of this study reassure the view that patients should be regarded as active decision makers. Patient education should be regarded as a cornerstone for treatment success. Additional studies as well are needed to test the practicability and effectiveness of interventions suggested to enhance adherence.
2. Hovstadius B, Petersson G. Non-adherence to drug therapy and drug acquisition costs in a national population - a patient-based register study. BMC Health Serv Res. 2011;11:326. doi: 10.1186/1472-6963-11-326
3. Cramer JA, Roy A, Burrell A, Fairchild CJ, Fuldeore MJ, Ollendorf DA, Wong PK. Medication compliance and persistence: terminology and definitions. Value Health. 2008;11(1):44-47. doi: 10.1111/j.1524-4733.2007.00213.x
4. Laufs U, Rettig-Ewen V, Böhm M. Strategies to improve drug adherence. Eur Heart J. 2011;32(3):264-268. doi: 10.1093/eurheartj/ehq297
5. Sokol MC, McGuigan KA, Verbrugge RR, Epstein RS. Impact of medication adherence on hospitalization risk and healthcare cost. Med Care. 2005;43(6):521-530.
6. Atella V, Peracchi F, Depalo D, Rossetti C. Drug compliance, co-payment and health outcomes: Evidence from a panel of Italian patients. Health Econ. 2006;15(9):875-892.
7. Martin LR, Williams SL, Haskard KB, DiMatteo MR. The challenge of patient adherence. Ther Clin Risk Manag. 2005;1(3):189-199.
8. Moore T, Neher J. Safranke S. FPIN’s clinical inquiries: improving medication adherence in patients with comorbidities. Am Fam Physician. 2011;84(7):1-2.
9. Claxton AJ, Cramer J, Pierce C. A systematic review of the associations between dose regimens and medication compliance. Clin Ther. 2001;23(8):1296-1310.
10. Coleman CI, Limone B, Sobieraj DM, Lee S, Roberts MS, Kaur R, Alam T. Dosing frequency and medication adherence in chronic disease. J Manag Care Pharm. 2012;18(7):527-539.
11. Bangalore S, Kamalakkannan G, Parkar S, Messerli FH. Fixed-dose combinations improve medication compliance: A meta-analysis. Am J Med. 2007;120(8):713-719.
12. Shrank WH, Hoang T, Ettner SL, Glassman PA, Nair K, DeLapp D, Dirstine J, Avorn J, Asch SM. The implications of choice: Prescribing generic or preferred pharmaceuticals improves medication adherence for chronic conditions. Arch Intern Med. 2006;166(3):332-337.
13. Briesacher BA, Andrade SE, Fouayzi H, Chan KA. Medication adherence and the use of generic drug therapies. Am J Manag Care. 2009;15(7):450-456.
14. Morisky DE, Ang A, Krousel-Wood M, Ward HJ. Predictive validity of a medication adherence measure in an outpatient setting. J Clin Hypertens (Greenwich). 2008;10(5):348-354.
15. EuroQol Group. EuroQol-a new facility for the measurement of health-related quality of life. Health Policy. 1990; 16(3):199-208.
16. 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):555-567.
17. Rolnick SJ, Pawloski PA, Hedblom BD, Asche SE, Bruzek RJ. Patient characteristics associated with medication adherence. Clin Med Res. 2013;11(2):54-65. doi: 10.3121/cmr.2013.1113
18. Gold D, McClung B. Approaches to patient education: Emphasizing the long- term value of compliance and persistence. Am J Med. 2006;119(4 Suppl 1):S32-S37.
19. DiMatteo M, Reiter R. Gambone J. Enhancing medication adherence through communication and informed collaborative choice. Health Communication. 1994;6(4):253-265.
20. Balkrishnan R. Predictors of Medication Adherence in the Elderly. Clin Ther. 1998;20(4):764-771.
21. Lau HS, Beuning KS, Postma-Lim E, Klein-Beernink L, de Boer A, Porsius AJ. Non-compliance in elderly people: Evaluation of risk factors by longitudinal data analysis. Pharm World Sci. 1996;18(2):63-68.
22. Fincke BG, Miller DR, Spiro A 3rd. The interaction of patient perception of overmedication with drug compliance and side effects. J Gen Intern Med. 1998;13(3):182-185.
23. Gadkari AS, McHorney CA. Unintentional non-adherence to chronic prescription medications: How unintentional is it really? BMC Health Serv Res. 2012;12:98. doi: 10.1186/1472-6963-12-98
24. Simpson SH, Eurich DT, Majumdar SR, Padwal RS, Tsuyuki RT, Varney J, Johnson JA. A meta-analysis of the association between adherence to drug therapy and mortality. BMJ. 2006;333(7557):15.
25. Saleem F, Hassali MA, Shafie AA, Awad GA, Atif M, ul Haq N, Aljadhey H, Farooqui M. Does treatment adherence correlates with health related quality of life? Findings from a cross sectional study. BMC Public Health. 2012;12:318. doi: 10.1186/1471-2458-12-318
26. Côté I, Farris K, Feeny D. Is adherence to drug treatment correlated with health-related quality of life? Qual Life Res. 2003;12(6):621-633.
27. Saleem F, Hassali MA, Shafie AA, Awad AG, Bashir S. Association between Knowledge and Drug Adherence in Patients with Hypertension in Quetta, Pakistan. Trop J Pharm Res. 2011;10(2):125-132.
28. Garber MC, Nau DP, Erickson SR, Aikens JE, Lawrence JB. The Concordance of Self-Report With Other Measures of Medication Adherence: A Summary of the Literature. Med Care. 2004 Jul;42(7):649-652.
29. Voils CI, Hoyle RH, Thorpe CT, Maciejewski ML, Yancy WS Jr. Improving the measurement of self-reported medication nonadherence. J Clin Epidemiol. 2011;64(3):250-254. doi: 10.1016/j.jclinepi.2010.07.014
30. Grymonpre RE, Didur CD, Montgomery PR, Sitar DS. Pill count, self-report, and pharmacy claims data to measure medication adherence in the elderly. Ann Pharmacother. 1998;32(7-8):749-754.
31. Briesacher BA, Andrade SE, Fouayzi H, Chan KA. Comparison of drug adherence rates among patients with seven different medical conditions. Pharmacotherapy. 2008;28(4):437-443. doi: 10.1592/phco.28.4.437
32. Glombiewski JA, Nestoriuc Y, Rief W, Glaesmer H, Braehler E. Medication adherence in the general population. PLoS One. 2012;7(12):e50537. doi: 10.1371/journal.pone.0050537