The quality of evidence is downgraded by inconsistency (variability in results).
A Cochrane review included 35 studies on interventions aiming at improved adherence to lipid lowering drugs, with a total of 925 171 subjects. Seven studies (n=11 204) compared adherence rates of those in an intensification of a patient care intervention (e.g. electronic reminders, pharmacist-led interventions, healthcare professional education of patients) versus usual care over the short term and were pooled in a meta-analysis. Participants in the intervention group had better adherence than those receiving usual care (table ). A separate analysis also showed improvements in long-term adherence rates (> 6 months) using intensification of care. Analyses of the effect on total cholesterol and LDL-cholesterol levels also showed a positive effect of intensified interventions over both short- and long-term follow-up. Over the short term, total cholesterol decreased by a mean of 17.15 mg/dL (95% CI 1.17 to 33.14; 4 studies, n=430; statistical heterogeneity I2=89%) and LDL-cholesterol decreased by a mean of 19.51 mg/dL (95% CI 8.51 to 30.51; 3 studies, n=333; statistical heterogeneity I2=53%). Over the long term (> 6 months) total cholesterol decreased by a mean of 17.57 mg/dL (95% CI 14.95 to 20.19; 2 studies, n=127). Included studies did not report usable data for health outcome indications, adverse effects or costs/resource use.
| Outcome | Relative effect (95% CI) | Risk with usual care | Risk with intensified patient care (95% CI) | Participants (studies) |
|---|---|---|---|---|
| * statistical heterogeneity, I2=88% | ||||
| Medication adherence at ≤ 6 months | OR 1.93 (1.29 to 2.88)* | 456 per 1000 | 618 per 1000 (519 to 707) | 11 204 (7 studies) |
| Medication adherence at > 6 month | OR 2.87 (1.91 to 4.29) | 705 per 1000 | 873 per 1000 (820 to 911) | 663 (3 studies) |