International Journal of Clinical Pharmacy

, Volume 33, Issue 6, pp 1028–1035 | Cite as

Diabetes knowledge, medication adherence and glycemic control among patients with type 2 diabetes

  • Harith Kh. Al-QazazEmail author
  • Syed A. Sulaiman
  • Mohamed A. Hassali
  • Asrul A. Shafie
  • Shameni Sundram
  • Rana Al-Nuri
  • Fahad Saleem
Research Article


Background Most of interventions that have attempted to improve medication adherence in type 2 diabetes have been educational; on the assumption that knowledge regarding diabetes might affect patients’ adherence to their treatment regimen. Objectives The purpose of the study was to investigate any association of knowledge and medication adherence with glycemic control in patients with type 2 diabetes mellitus. Setting The study was conducted at the Diabetes Outpatients Clinic, Hospital Pulau Penang. Methods A cross-sectional study was conducted with a convenience sample of 540 adult patients with type 2 diabetes attending the clinic. A questionnaire including previously validated Michigan Diabetes Knowledge Test and Morisky Medication Adherence Scale was used and the patients’ medical records were reviewed for haemoglobin A1C (HbA1C) levels and other disease-related information. A total of 35 (6.48%) patients were excluded after data collection due to lack of HbA1C results. Results Five hundred and five patients were included in the final analysis, with a mean age of 58.15 years (SD = 9.16), 50.7% males and median HbA1C of 7.6 (IQR was 6.7–8.9). The median total knowledge score was 7.0 (IQR was 5.0–10.0) while the median adherence score was 6.5 (IQR was 4.75–7.75). Significant correlations were found between the three variables (HbA1C, knowledge and adherence). A significantly higher score for knowledge and adherence (P < 0.05) was found in those patients with lower HbA1C. Higher diabetes knowledge, higher medication adherence and using mono-therapy were significant predictors of good glycemic control in the multivariate analysis. Conclusion Patients’ knowledge about diabetes is associated with better medication adherence and better glycemic control. In addition to other factors affecting medication adherence and glycemic control, healthcare providers should pay attention to knowledge about diabetes that the patients carry towards medication adherence.


Diabetes type 2 Glycemic control Knowledge Medication adherence 



The study was funded by a university research grant (1001/PFARMASI/811119) from the Universiti Sains Malaysia.

Conflict of interest



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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Harith Kh. Al-Qazaz
    • 1
    Email author
  • Syed A. Sulaiman
    • 1
  • Mohamed A. Hassali
    • 2
  • Asrul A. Shafie
    • 2
  • Shameni Sundram
    • 3
  • Rana Al-Nuri
    • 4
  • Fahad Saleem
    • 2
  1. 1.Discipline of Clinical Pharmacy, School of Pharmaceutical SciencesUniversiti Sains MalaysiaPenangMalaysia
  2. 2.Discipline of Social and Administrative Pharmacy, School of Pharmaceutical SciencesUniversiti Sains MalaysiaPenangMalaysia
  3. 3.Hospital Balik PulauPenangMalaysia
  4. 4.Advanced Medical and Dental InstituteUniversiti Sains MalaysiaPenangMalaysia

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