Mediators of medication adherence and glycaemic control and their implications for direct outpatient medical costs: a cross‐sectional study. Issue 6 (30th March 2018)

• Record Type: Journal Article
• Authors: Lum, Z. K.; Tsou, K. Y. K.; Lee, J. Y.‐C.
• Is Part Of: Diabetic medicine. Volume 35:Issue 6(2018)
• Page Start: 807
• Page End: 815
• Publication Date: 2018-03-30
• Subjects: Diabetes -- Periodicals; 616.462
• DOI: 10.1111/dme.13619
• Languages: English
• ISSNs: 0742-3071

Abstract

Abstract: Aims: To investigate the effects of diabetes‐related distress and perception of hyperglycaemia on self‐reported medication adherence and glycaemic control, as measured by HbA1c, and to compare the cost outcomes in patients with sub‐optimally vs uncontrolled Type 2 diabetes mellitus. Methods: We conducted a retrospective cross‐sectional study that involved the review of a chronic disease database in Singapore. Data on clinical characteristics, diabetes‐related distress, perception of hyperglycaemia, self‐reported medication adherence and costs were obtained from the database. Mediation analyses were conducted using a linear regression‐based approach. A final path model was built to illustrate the sequential mediating effects of diabetes‐related distress and perception on the association of medication adherence and HbA1c concentration. Results: Diabetes‐related distress and perception of hyperglycaemia were significantly associated with medication adherence and HbA1c concentration. Mediation analyses showed a significant indirect effect of diabetes‐related distress and perception of hyperglycaemia on medication adherence and HbA1c concentration. People with uncontrolled diabetes were found to incur significantly higher total direct medical costs than those with sub‐optimally controlled diabetes ( P = 0.034), with medication cost as the main cost driver (66.6%). Conclusions: Identifying the influence of the sequential mediating effects of distress and perception was important in understanding the pathway between medication adherence and glycaemic control. This suggests the importance of a team‐based approach to address these mediators and thus improve glycaemic control. Poor glycaemic control was also found to be associated with higher direct medical costs. What's new?: This study adopted regression‐based mediation analysis to identify mediators of the relationship between self‐reported medication adherence and glycaemic control. Diabetes‐related distress and perception of hyperglycaemia were found to mediate the relationship between adherence and glycaemic control sequentially, which highlighted the importance of addressing distress and perception to improve glycaemic control. Poor glycaemic control was also found to be associated with higher direct medical costs, which might result in higher distress. This study presented the complex interactions between clinical, behavioural, cognitive and emotional factors in diabetes management that should all be accounted for in the design of interventions.