The British Journal of Diabetes & Vascular Disease. 2010;10(3):148-152.
People with type 2 diabetes are often prescribed multi-medicines which can be difficult
to manage. Non-adherence to medicines can be intentional (e.g. active decision) or
unintentional (e.g. forgetting). The objective of this study was to measure intentional
and unintentional non-adherence to differing numbers of medicines prescribed in type
2 diabetes. A cross-sectional survey using the Morisky medication adherence scale
(with intentional and unintentional non-adherence subscales) was completed by 480
people prescribed oral antidiabetic drugs (OADs), antihypertensive agents and statins.
A within-subject analysis of variance (ANOVA) showed that intentional non-adherence
did not vary between OADs, anti-hypertensives and statins. Intentional non-adherence
to statins significantly increased when the number of medicines prescribed was included
as a between-subjects variable (p<0.05). Another within-subject ANOVA on unintentional
non-adherence found a significant difference between OADs, anti-hypertensives and
statins; unintentional non-adherence to OADs was significantly higher (p<0.05). When
the number of medicines was added as a between-subject variable unintentional non-adherence
was associated with higher numbers of medicines. This study shows the difference between
intentional and unintentional non-adherence behaviours, and the effect that varying
numbers of medicines can have on these behaviours.