Distress and type 2 diabetes-treatment adherence: A mediating role for perceived control

Health Psychol. 2015 May;34(5):505-13. doi: 10.1037/hea0000131. Epub 2014 Aug 11.


Objective: To better understand independent pathways linking emotional distress, medication adherence, and glycemic control in adults with Type 2 diabetes, as well as the potential mediating effects of perceived control over illness and self-efficacy.

Method: Adults with Type 2 diabetes (N = 142) were recruited for an intervention study evaluating cognitive-behavioral therapy for adherence and depression. Depressive symptom severity was assessed via semistructured interview. Validated self-reports assessed diabetes-related distress, perceived control over diabetes (perceived control), self-efficacy for diabetes self-management, and medication adherence. Glycemic control was evaluated by hemoglobin A1C. Only baseline data were included in correlational and linear regression analyses.

Results: Perceived control was an important mediator of emotional distress for both medication adherence and A1C outcomes. Specifically, regression analyses demonstrated that diabetes distress, but not depression severity, was significantly related to medication adherence and A1C. Self-efficacy and perceived control were also independently associated with medication adherence and A1C. Mediation analyses demonstrated a significant indirect effect for diabetes distress and medication adherence through perceived control and self-efficacy. The relationship between distress and A1C was accounted for by an indirect effect through perceived control.

Conclusion: Results demonstrated that diabetes-related emotional distress is associated with poorer treatment adherence and glycemic control among adults with Type 2 diabetes; these relationships were partially mediated through perceived control over diabetes. Perceptions of one's personal ability to influence the course of diabetes may be important in understanding the pathway between emotional distress and poor diabetes-treatment outcomes.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Blood Glucose
  • Depression / psychology
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetes Mellitus, Type 2 / psychology*
  • Female
  • Glycated Hemoglobin / analysis
  • Humans
  • Internal-External Control*
  • Male
  • Medication Adherence / psychology*
  • Middle Aged
  • Self Care / psychology
  • Self Efficacy*
  • Self Report
  • Stress, Psychological / psychology*


  • Blood Glucose
  • Glycated Hemoglobin A