The Impact of Single Pill Combination Versus Free Dose Equivalent on Outcomes in Patients With Hypertension and/or Dyslipidaemia: A Systematic Review

OBJECTIVES: Assess the impact of single pill combination (SPC) on clinical, quality of life (QoL), and economic outcomes in hypertension and dyslipidaemia, relative to their free dose equivalent (FDE).

METHODS: EMBASE, PubMed-Medline, and Cochrane were searched from inception until 11/05/2021. No country or language restrictions were applied. Eligible studies had to compare SPCs against FDEs in hypertension and dyslipidaemia, and report adherence, persistence, clinical, QoL, and economic outcomes.

RESULTS: Of 16,310 publications, 52 studies were included, 39 including patients with HT, 7 with HT and DL, and 6 with DL. Results were consistent for patients with hypertension, showing higher adherence and persistence rates on SPCs compared with FDEs. In treatment naïve patients with dyslipidaemia there were statistically significant improvements in adherence and persistence in those treated with SPCs compared with FDEs. Treatment experienced patients with dyslipidaemia reported non-significant improvements in adherence and persistence when treated with SPCs compared with FDEs; in all studies except one, which reported an opposite trend. Improvements seen in adherence and persistence for hypertension and dyslipidaemia range between 34.2% - 98.9% and 33% - 76%, respectively for each outcome. Studies reporting clinical outcomes, showed that SPC-treated patients experienced higher reduction in patients’ blood pressure (BP) or cholesterol levels, which resulted in a decrease in incidence of cardiovascular events and lower healthcare costs and resource use.

CONCLUSIONS: SPCs increase adherence and persistence to treatment compared to FDEs in patients with hypertension and/or dyslipidaemia. Evidence for patients with hypertension suggest a potential link between improved adherence and persistence and improved BP control and reduction in the risk of cardiovascular events. Consistently, studies reported lower total direct healthcare costs for SPC-treated patients with hypertension or dyslipidaemia compared with FDEs-treated. However, further evidence is needed on the effect of using SPCs on QoL, and to better quantify the differences in outcomes through a meta-analysis.