β-Blocker use and diabetes symptom score: results from the GEMINI study

The Glycemic Effect in Diabetes Mellitus: Carvedilol-Metoprolol Comparison in Hypertensives (GEMINI) trial compared the metabolic effects of two β-blockers in people with type 2 diabetes and hypertension treated with renin-angiotensin system (RAS) blockade and found differences in metabolic outcomes. In this paper, we report the results of a prespecified secondary analysis of GEMINI that sought to determine the effect of these two β-blockers on commonly reported symptoms. The Diabetes Symptom Checklist (DSC), a self-report questionnaire measuring the occurrence and perceived burden of diabetes-related symptoms, was completed by GEMINI participants at baseline and at the end of the study (maintenance month 5). The DSC assessed symptoms in eight domains: psychology (fatigue), psychology (cognitive), neuropathy (pain), neuropathy (sensory), cardiology, ophthalmology, hyperglycaemia and hypoglycaemia. Comparison of the mean change in self-reported diabetes-related symptoms indicated a significant treatment difference favouring carvedilol over metoprolol tartrate in overall symptom score (-0.08; 95% CI -0.15, -0.01; p = 0.02) and in the domains for hypoglycaemia symptoms (-0.12; 95% CI -0.23, -0.02; p = 0.02) and hyperglycaemia symptoms (-0.16; 95% CI -0.27, -0.05; p = 0.005). Carvedilol resulted in fewer perceived diabetes-related symptoms in patients with diabetes and hypertension. Carvedilol resulted in a lower perceived burden of diabetes-related symptoms in patients with type 2 diabetes and hypertension. The addition of a well-tolerated β-blocker to RAS blockade may improve hypertension treatment and quality of life in patients with diabetes.