John: Hello, I'm John Hilton, editor of the Cochrane Editorial unit. Statins are very widely prescribed to lower cholesterol and it’s important to know the best ways to help patients to take them. In an updated Cochrane Review from December 2016, Mieke van Driel from the University of Queensland in Australia examines the evidence, and she tells us more in this podcast.

Mieke: High cholesterol is one of the risk factors for cardiovascular disease and doctors may decide to treat high cholesterol if the risk is high. Drugs that reduce cholesterol (or lipids) in the blood also reduce the risk of heart attacks and strokes, as well as reducing mortality. These lipid-lowering drugs include different classes, such as statins, fibrates and resins, but they are commonly referred to collectively as ‘statins’, the most widely used class.
Despite compelling evidence that lipid-lowering drugs are effective, they are still underused, and among those receiving lipid-lowering therapy, ideal cholesterol levels are achieved in fewer than half, with only 1 in 4 patients taking their medication long term. This poor ‘adherence’ to therapy is directly related to increases in mortality or recurrence of cardiovascular events in people at high risk and, so, improving adherence can benefit both individuals as well as population health.
Many factors can influence adherence, including adverse effects, denial, inadequate knowledge about the treatment, impaired memory, and unreceptive attitudes to treatment. People with high cholesterol mostly do not experience any symptoms, which makes it particularly challenging to motivate them to take their medication. 
In the past, several methods have been tried to improve adherence to these lipid-lowering treatments, but previous versions of this Cochrane Review did not show a clear benefit of any particular method. However, we now live in a more digital age and we updated the review to see if any of the new methods might improve adherence and it looks as though they might do so.
We found 24 new randomised trials that compared adherence enhancing interventions to standard care, bringing the total number of included studies to 35. The more than 900,000 participants in these studies were adults over 18 years of age in outpatient settings, for whom lipid-lowering therapy was recommended.
Sixteen of the interventions in the 35 studies were categorised as 'intensified patient care'. They included electronic reminders, pharmacist-led interventions, and healthcare professional education to help people remember to take their tablets. These types of interventions showed significantly better adherence rates than standard care in both the first six months and in the longer term. Additionally, cholesterol levels were better in those offered the intervention. This suggests that healthcare systems which can implement team-based intensification of patient care interventions may be successful in improving patient adherence to lipid-lowering medicines, which would help to achieve the benefits of these drugs.

John: If you would like to read more about these interventions and their effects on adherence, you can find the full Cochrane Reviews online. Just go to Cochrane Library dot com and search 'lipid lowering and adherence'.