The effectiveness of counselling interventions in reducing HbA 1c concentrations in patients with type 2 diabetes: a modelling study

Background The burden of type 2 diabetes is increasing rapidly in the occupied Palestinian territory. Different counselling interventions have been applied worldwide to reduce HbA 1c concentrations in patients with type 2 diabetes. Achieving good glycaemic control is important for prevention of complications of type 2 diabetes. The aim of this modelling study was to assess the effectiveness of different counselling interventions in improving glycaemic control in patients with type 2 diabetes. Methods The scientific literature was reviewed to identify relevant interventions that can reduce HbA 1c concentrations in patients with type 2 diabetes. We included articles describing interventions tested at the primary health-care level and targeting patients with type 2 diabetes. Based on WHO's "Best Buys", and taking into consideration their feasibility, acceptability, and potential effectiveness, we identified different forms of counselling interventions at the primary health-care level. The effect of each identified intervention on HbA 1c concentrations and the duration of this effect were collected in predefined tables. A regression line was plotted to find an estimate of the effect of each intervention through calculating the correlation between the changes in HbA 1c from each intervention versus the duration of the intervention. The unstandardised β-coefficient was identified for each intervention to predict its effectiveness in reducing HbA 1c concentrations. Findings We identified three main effective counselling interventions at the primary health-care level: (1) individual counselling intervention by multidisciplinary teams of health-care professionals, which provided individual counselling sessions depending on the patients' glycaemic control status; (2) the community health-worker intervention, which provided a set of home counselling visits for patients with uncontrolled type 2 diabetes; and (3) short message service (SMS)-based intervention (sending patients a number of counselling SMS weekly). All interventions were effective in reducing mean HbA 1c concentrations in patients with type 2 diabetes. The SMS-based intervention was the most effective (β=0·65, R 2 =0·10), followed by the community health-worker intervention (β=0·27, R 2 =0·28) and the individual counselling intervention (β=0·14, R 2 =0·01). Interpretation We compared the effectiveness of a set of interventions that are considered relativity low cost and applicable at the level of primary health care (the "Best Buys"). Implementing at least one of these effective interventions within the Palestinian health-care system could help improve glycaemic control and eventually reduce the prevalence of complications associated with type 2 diabetes. Controlling HbA 1c concentration will not only reduce the epidemiological burden of type 2 diabetes and its complications but it will also reduce the economic burden within Palestinian health-care system. Funding Eastern Mediterranean Regional office of WHO.