Pharmacist Interventions in the Management of Type 2 Diabetes Mellitus: A Systematic Review of Randomized Controlled Trials

BACKGROUND: Diabetes mellitus is a major health problem that is growing rapidly worldwide. A collaborative and integrated team approach in which pharmacists can play a pivotal role should be sought when managing patients with diabetes. OBJECTIVE: To identify and summarize the main outcomes of pharmacist interventions in the management of type 2 diabetes. METHODS: PubMed, Cochrane Central Register of Controlled Trials, and Web of Science were searched for randomized controlled trials evaluating the effectiveness of any pharmacist intervention directed at patients with type 2 diabetes in comparison with usual care. Outcome measures of interest included glycosylated hemoglobin (Alc), blood glucose, blood pressure, lipid profile, body mass index (BMI), 10-year coronary heart disease (CHD) risk, medication adherence, health-related quality of life (HRQoL), and economic outcomes. The risk of bias in included studies was assessed using the Cochrane risk of bias tool. RESULTS: Thirty-six studies were included in this systematic review, involving 5,761 participants. The studies evaluated the effects of several pharmacist interventions carried out in various countries and in different health care facilities, such as community pharmacies, primary care clinics, and hospitals. The number of studies reporting each outcome of interest varied. Alc was evaluated in 26 studies, of which 24 reported a greater reduction in this outcome in the intervention group compared with the control group, with the difference in change between groups ranging from -0.18% to -2.1%. Eighteen studies assessed change in systolic blood pressure, of which 17 studies reported a greater improvement in this outcome in the intervention group, with the difference in change between groups varying between -3.3 mmHg and -23.05 mmHg. For diastolic blood pressure, a greater effect was also observed in the intervention group in 14 out of 15 studies, with the difference in change between groups varying between -0.21 mmHg and -9.1 mmHg. Thirteen studies described total cholesterol as an outcome measure, of which 10 reported a greater improvement in this outcome in the intervention group, with the difference in change between groups ranging from +18.95 mg dL(-1) to -32.48 mg dL(-1). With regard to low-density lipoprotein cholesterol, a greater reduction in this parameter in the intervention group was documented in 12 out of 15 studies, with the difference in change between groups varying between +7.35 mg dL(-1) and -30 mg dL(-1). Similarly, favorable data were reported on high-density lipoprotein cholesterol in the intervention group in 9 out of 12 studies that assessed this outcome, with the difference in change between groups ranging from -5.8 mg dL(-1) to +11 mg dL(-1). Data on triglycerides were also reported in 12 studies, of which 9 reported a greater reduction in triglycerides levels in the intervention group, with the difference in change between groups varying between +12 mg dL(-1) and -62 mg dL(-1). Overall, a beneficial effect on BMI was also described in the intervention group in 12 out of 14 studies. Of note, in all 6 studies that estimated the 10-year CHD risk among study patients, a greater improvement in the intervention group versus the control group was found. In addition, pharmacist interventions also had a positive impact on medication adherence and HRQoL in most studies that ascertained these outcomes. Finally, although only 3 studies conducted a cost-effectiveness analysis, pharmacist interventions proved to be cost-effective. CONCLUSIONS: The findings from this review clearly support the involvement of pharmacists as members of health care teams in the management of patients with type 2 diabetes.