Introduction
Statins are a proven therapy to lower serum cholesterol
concentrations, reducing the long-term risk of ischaemic heart
disease events by about 60% and stroke by 17% 1.
Despite these therapeutic advantages, medication adherence to statins
(defined as the extent to which the patient’s medication taking behavior
corresponds with the agreed recommendations from the healthcare
provider) is suboptimal and varies between 32-77%2-8.
Non-adherence to statin therapy has a negative impact on treatment
outcomes. Patients with poor adherence to statins are at greater risk of
cardiovascular events and hospitalization due to cardiovascular disease
and cause avoidable high health care costs 9-15. This
makes improving medication adherence to statin therapy a key component
of the treatment of hypercholesteremia 9,16.
Adherence is multifactorial; “Health-system/Health-care team factors”,
“Social/economic factors”, “Condition-related factors”,
“Therapy-related factors” and “Patient-related factors” have been
associated with/implicated in non-adherence 9..
Previous research on interventions to improve adherence to statins
mainly focused on “patient-related factors”, however these studies
yielded small inconsistent results, with a range of effect of these
interventions from -3% up to 25% improvement of adherence17-20. Therefore, interventions that target other
factors that can have impact on adherence might also be required, like
relevant factors in the health-system/health-care 9.
Yet, evidence on the impact of health-system/health-care team factors on
implementation adherence to statins is scarce. Insight into the
association between relevant factors in the health system/health-care
team and adherence is warranted.
Earlier studies demonstrated health system factors like continuity of
care and complete treatment information are factors that are positively
associated with adherence to drug treatment in chronic conditions as
well as in statin use 16,21,22. Furthermore, patients
who experienced a higher quality of care and/or a higher degree of
shared decision making had more knowledge of their illness, were more
actively involved in their own treatment, were more confident in their
communication with healthcare providers and had higher adherence rates23,24. The aforementioned examples in literature are
about the impact of the overall quality of care on adherence, whereas
literature about the impact of the quality of care activities employed
by individual HCPs is scarce. Based on the findings about the positive
impact of the overall quality of care on adherence, it is also
conceivable that quality of care activities, including usual care
adherence support activities) of a single HCP, might positively
influence patients’ medication adherence. Noteworthy, influencing the
usual care of one single healthcare provider may affect the adherence of
several patients, which makes interventions on HCP level potentially
more impactful than interventions on patient level. Currently, no
evidence is available about physicians’ and pharmacy staff’s’ usual care
to support adherence to statins and how this care affects patients’
adherence.
The aim of this study is 1) to describe the nature and extent of
adherence supporting activities provided in a usual care setting by
physicians, pharmacists and pharmacy technicians; and 2) to examine the
relation between the extent of adherence supporting activities of
physicians, pharmacists and pharmacy technicians and adherence to
statins. We hypothesized that increased HCPs’ usual care activities to
support statin adherence have a positive impact on patients’
implementation adherence to statins.