Hypertension Canada guideline for the diagnosis and treatment of hypertension in adults in primary care.

76 Compared with free-drug combinations, single-pill combinations are associated with significantly better drug adherence (OR 1.21, 95% CI 1.03–1.43) and a possible trend toward better drug persistence (OR 1.54, 95% CI 0.95–2.49). 77 An observational study of more than 100,000 patients with hypertension showed that upfront combination therapy reduced therapeutic inertia, as these patients were over 2-fold more likely to be on a multidrug prescription at 3 years

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