Factors contributing to nonadherence to oral hypoglycemic medications among ambulatory type 2 diabetes patients in Southwestern Nigeria
Objective: The overall goal of the study was to evaluate the probable reasons for patients’ nonadherence to prescribed oral hypoglycemic medications in an ambulatory care setting in Nigeria with a view to identifying points for necessary intervention to improve adherence and treatment outcomes. Also, the recommended non-drug management options for diabetes patients with emphasis on self monitoring of blood glucose were assessed.
Methods: A cross-sectional study was conducted at a 200-bed secondary health care facility in Southwestern Nigeria between 2nd April and 31st May 2008. Copies of pre-tested questionnaire were administered directly to 121 ambulatory patients with type 2 diabetes at the study site. Information on socio-demographic characteristic, probable barriers that affect adherence to prescribed oral hypoglycemic medications, non-drug treatment options for diabetes, and patients’ self management efforts were obtained. Descriptive and chi-square statistics were used to evaluate the distribution of respondents’ opinion.
Results: The response rate was almost 100%. The commonly cited intentional nonadherence practice included dose omission (70.2%). Almost 50% respondents were fed up with daily ingestion of drugs and 19.8% were inconvenienced with taking medications outside home and gave these as reasons for the dose omission. Forgetfulness (49.6%) and high cost of medication (35.5%) were mentioned as major non-intentional reasons for nonadherence. Aside oral medications, 82.6% and 95.0% of respondents respectively, reported moderate exercise and dietary restrictions as part of the prescribed treatment modalities. More than two third of respondents (81.8%) had never monitored blood glucose by themselves. Significant association exist between sex, occupation and patients’ tendencies to forget doses of prescribed oral medications (p<0.05).
Conclusion: Nonadherence behaviors among ambulatory patients with type 2 diabetes occur mostly, as omission and forgetfulness of doses of medication. Efforts are needed to increase the medication adherence and self management practices of these patients in Nigeria so they can realize the full benefits of prescribed therapies.
2. International Diabetes Federation. Diabetes Prevalence 2005. http://www.idf.org/home/index.cfm?
3. King H, Rewers M. Global estimates for the prevalence of diabetes mellitus and impaired glucose tolerance in adults. WHO Ad Hoc Reporting Group. Diabetes Care. 1993;16:157-177.
4. Olatunbosun ST, Ojo PO, Fineberg NS, Bella AF. Prevalence of diabetes mellitus and impaired glucose tolerance in a group of urban adults in Nigeria. J Natl Med Assoc. 1998;90:293-301.
5. Helmrich SP, Rayland RW, Leung RS. Paffen- berger, physical activity and reduced occurrence of NIDDM. N Engl J Med. 1991;325(4):147-151.
6. Mark AM, Benjamen W, Van Tassell JL. Medication Nonadherence; An Unrecognized Cardiovascular Risk Factor. Mediscape General Medicine. 2007;9(3):58.
7. Rozenfeld Y, Hunt JS, Plauschinat C, Wong KS. Oral antidiabetic medication adherence and glycemic control in managed care. Am J Manag Care. 2008;14:71-75.
8. Cramer JA. A systematic review of adherence with medications for diabetes. Diabetes Care. 2004;27:1218-1224.
9. Schetman JM, Nadkarni MM, VossJD. The association between diabetes metabolic control and drug adherence in an indigent population. Diabetes Care. 2002;25:1015-1021.
10. Krapek K, King K, Warrien SS, et al. Medication adherence and associated hemoglobin AIC in type 2 diabetes. Ann Pharmcother. 2004;38:1357-1362.
11. The DCCT Research Group: The effect of intensive treatment of diabetes on the development and progression of long term complications in IDDM. N Engl J Med 1993;329:977-986.
12. Lee WC, Balus Cobden D, Joshi AV, Pashos CL. Prevalence and economic consequences of medication adherence on diabetes; a systematic literature review. Manag Care Interface. 2006;19:31-41.
13. Sokol MC, McGuigan KA, Verbrugge RR, Epstein RS. Impact of medication adherence on hospitalization risk and healthcare cost. Med Care. 2005;43:521-530.
14. Anderson DKG, Svardsudd K: Long term glycemic control relates to mortality in type 2 diabetes. Diabetes Care. 1995; 18:1534-1543.
15. Ohkubo Y, Kishikawa H, Araki E, Isamis S, Motoyoshi, Kojima Y, Furuyoshi N, Shichiri M. Intensive insulin therapy prevents the progression of diabetic microvascular complications in Japanese patients with non-insulin dependent diabetes mellitus: a randomized prospective 6-year study. Diabetes Res Clin Pract. 1995;28:103-117.
16. Jacques CHM, Jones RL: Problems encountered by primary care physicians in the care of patients with diabetes. Arch Fam Med. 1993;2:739-741.
17. Lutfey KE, Wishner WJ: Beyond “Compliance’’ is “adherence’’. Improving the prospect of diabetes care. Diabetes Care. 1999; 22:635-639.
18. Rubin RR, Peyrot M. Men and Diabetes: Psychosocial and Behavioural issues. Diabetes Spectrum. 1998;11:81-87.
19. Mckay HG, Boles SM, Glasgow RE. Personality (Conscientiousness) and environmental (barriers) factors related to diabetes self management and quality of life. Diabetes Care. 1998;44:170-173.
20. Vileiktye L. Psychological aspects of diabetic peripheral neuropathy. Diabetes Rev. 1999;7:387-393.
21. Golin CE, DiMatteo MR, Gelberg L. The role of patient participation in doctor visit- Implications for adherence to diabetic care. Diabetes Care 1996;19(10):1153-1164.
22. Peterson T, Lee P, Hollis S, Young B, Newton P, Donovan T. Well-being and treatment satisfaction in older people with diabetes. Diabetes Care. 1998;1(3):169-174.
23. Diehl AK, Bauer RL, Sugarek N. Correlates of medical compliance in non-insulin dependent diabetes mellitus. Diabetes Care. 1985;8:219-223.
24. Botelho R, Dudrak R. Home Assessment of Adherence to long –term medication in the elderly. J Family Pract. 1992;35:61-64.
25. Anderson R, Kirk L. Methods of improving patient compliance in chronic Disease state. Arch Intern Med. 1982;142:1673-1675.
26. Amos AF, McCarty DJ, Zimmet P. The rising global burden of diabetes and its complications, estimates and projection to the year 2010. Diabetic Medicine. 1997;14(suppl 5):S1-S85.
27. Unwin N, Sobugwi E, Alberto KGMM. Type 2 diabetes: the challenge of preventing a global epidemic. Diabetes Int. 2001;11:4-8.
28. World Health Organization. Prevention of diabetes mellitus. Report of a WHO study Group. WHO Technical Report Series 844. Geneva WHO, 1994.
29. StatDirect-Statistical software which link to Microsoft Excel. http://statdirect.com/
30. EpiInfo-free epidemiology/statistics software from CDC, Atlanta. http://www.cdc.gov/epiinfo/
31. Sample size Tables for clinical studies (2nd Edition, 1997) by Machin D, Campbell M, Fayers P & Pinol A- Published by Blackwell Science Ltd (ISBN 0-86542-870-0).
32. Paes AH, Baker A, Soc-Agnie CJ. Impact of dosage frequency on patient compliance. Diabetes Care 1997;20:1512-1517.
33. Dunbar J. Predictors of patient adherence: Patient characteristics. In Shumaker S., Eleanor B., (Eds). The handbook of health behaviour change 1990. New York, NY, USA: Springer Publishing Co Inc.
34. Talbot F, Nouwen A, Gingras J. Relations of Diabetes Intrusiveness and Personal Control to Symptoms of Depression Among Adults With Diabetes. Health Psychol. 1999;18:537-542.
35. Ho PM, Rumsfeld JS, Masoudi FA, McClure DL, Plomondon ME, Steiner JF, Magid DJ.Effect of Medication nonadherence on hospitalization and mortality among patients with diabetes mellitus. Arch Intern Med. 2006;166:1836-1841.
36. Ary DV, Toobert D, Wilson W, Glasgow RE. Patient perspective on factors contributing to nonadherence to diabetes regimen. Diabetes Care 1986; 9:168-172.
37. Jayant D, Lawrence B, Richard G. Factor Influencing Patient Acceptability of Diabetes Treatment Regimens. Clinical Diabetes 2000; Vol l8 No2 Spring
38. Korzon-Burakowska A, Hopkins D, Matyka K, Lomas J, Pernet A, Macdonald I, Amiel S. Effects of glycemic control on protective responses against hypoglycemia in type 2 diabetes. Diabetes Care. 1998;21(2):283-290.
39. Hsaio LD, Salmon JW. Predicting adherence to prescription medication purchase among HMO enrollees with diabetes. J Manag Care Pharm. 1999;5(4):336-341.
40. Linda CC. Health education and Health promotion (In): Suzame CS &Brenda GB. (Eds) Brunner and Sudddarth’s textbook of medical surgical nursing (10th edition), Lippincott William and Wilkins; 2004 Pp 46-47.
41. Ohene Buabeng K, Motowel L, Plange-Rhule J. Unaffordable drug prices: the major cause of noncompliance with hypertensive medication in Ghana. J Pharm Sci. 2004;7:350-352.
42. Harris MI, Cowie CC, Howie LJ. Self monitoring of blood glucose by adults with diabetes in the United States population. Diabetes Care 1993;16:1116-1123.
43. Vik SA, Maxwell CJ, Hogan DB, Patten SB, Johnson JA, Romonko-Slack L. Assessing medication adherence among older persons in community settings. Can J Clin Pharmacol. 2005;12(1):el52-el64.
44. Gordis L, Markowitz M, Lilienfield AM. The inaccuracy in using interviews to estimate patient reliability in taking medication at home. Med Care. 1969;7(1):49-54.
45. Morisky DE, Green LW, Levine DM. Current and predictive validity of a self reported measure of medication adherence. Med Care. 1986;24;67-74.