Predictors of non-adherence to pharmacotherapy in patients with type 2 diabetes

Int J Clin Pharm. 2014 Aug;36(4):725-33. doi: 10.1007/s11096-014-9938-5. Epub 2014 May 8.

Abstract

Background: The prevalence of diabetes in Jordan is among the highest in the world, making it a particularly alarming health problem there. It has been indicated that poor adherence to the prescribed therapy lead to poor glycemic control and enhance the development of diabetes complications and unnecessary hospitalization.

Objective: To explore factors associated with medication nonadherence in patients with type 2 diabetes in Jordan. Findings would help guide the development of future pharmaceutical care interventions for patients with type 2 diabetes.

Setting: This study was conducted in an outpatient diabetes clinic at the Royal Medical Services Hospital.

Method: Variables including sociodemographics, disease and therapy factors, diabetes knowledge, health-related quality of life in addition to adherence assessment were collected for 171 patients with type 2 diabetes using medical records, custom-designed and validated questionnaires. Logistic regression was performed to develop a model with variables that best predicted medication non-adherence in patients with type 2 diabetes in Jordan.

Main outcome measure: Variables which significantly and independently associated with medication nonadherence in patients with type 2 diabetes in Jordan.

Results: Patients were found four times less likely to adhere to their medications with each unit increase in the number of prescribed medications (OR = 0.244, CI = 0.08-0.63) and nine times less likely to adhere to their medications if they received more than once daily dosing of diabetic medication (OR = 0.111, CI = 0.04-2.01). Patients in the present study were also approximately three times less likely (OR = 0.362, CI = 0.24-0.87) and twice less likely (OR = 0.537, CI = 0.07-1.31) to adhere to their medications if they reported having concerns about side effects and if they were taking metformin therapy respectively. Finally, participants were found twice more likely to adhere to medications if they had one or more Microvascular complication (OR = 0.493, CI = 0.08-1.16).

Conclusion: Simplifying dosage regimen, selecting treatments with lower side effects along with an emphasis on diabetes complications should be taken into account in future interventions designed to improve health outcomes for patients with type 2 diabetes.

MeSH terms

  • Aged
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetic Angiopathies / prevention & control
  • Drug Administration Schedule
  • Drug Therapy, Combination / adverse effects
  • Female
  • Follow-Up Studies
  • Health Knowledge, Attitudes, Practice
  • Hospitals, Urban
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Hypoglycemic Agents / adverse effects
  • Hypoglycemic Agents / therapeutic use
  • Jordan
  • Logistic Models
  • Male
  • Medication Adherence*
  • Metformin / administration & dosage
  • Metformin / adverse effects
  • Metformin / therapeutic use
  • Middle Aged
  • Models, Biological*
  • Outpatient Clinics, Hospital
  • Peripheral Vascular Diseases / complications
  • Peripheral Vascular Diseases / prevention & control
  • Precision Medicine*
  • Quality of Life

Substances

  • Hypoglycemic Agents
  • Metformin