Evaluation of the clinical effectiveness of telephone consultation compared to face-to-face consultation in terms of glycaemic control among patients with suboptimally controlled type 2 diabetes: a retrospective cohort study.

Objective: With the COVID-19 pandemic, telemedicine has been increasingly deployed in lieu of face-to-face consultations for management of diabetes in primary care. There was a need to evaluate clinical effectiveness of telephone consultations for diabetes management and this study aimed to show whether one-off telephone consultation was inferior or not to face-to-face consultation in terms of glycaemic control among patients with suboptimally controlled type 2 diabetes.

Design: Retrospective cohort study. Data of all patients with type 2 diabetes who had a chronic disease consultation during the period 9 April 2020-18 September 2020, and met the study's inclusion and exclusion criteria was obtained from the electronic medical records.

Setting: A primary care clinic in the north-eastern region of Singapore. The clinic's patient population was representative of Singapore's population in terms of gender and age.

Participants: 644 patients with type 2 diabetes and glycated haemoglobin (HbA1c) 7.0% and above, aged 21-80 years old.

Interventions: Participants either underwent telephone or face-to-face consultation for diabetes management.

Outcome Measure: Mean HbA1c change (∆HbA1c) between preintervention and postintervention.

Results: Over 4 months, the mean ∆HbA1c was -0.16 percentage points (p.p.) (95% CI -0.26 to -0.07) and -0.11 p.p. (95% CI -0.20 to -0.02) for face-to-face and telephone consultation groups, respectively. The difference in mean ∆HbA1c between the two groups was +0.05 p.p. (95% CI -∞ to 0.16), with the upper limit of the one-sided 95% CI less than the prespecified non-inferiority margin of 0.5 p.p. (p<0.05). In those with HbA1c≥9%, the difference in mean ∆HbA1c was +0.31 p.p. (95% CI -∞ to 0.79), which exceeded the non-inferiority margin.

Conclusion: For patients with suboptimally controlled type 2 diabetes, one-time telephone consultation was non-inferior to face-to-face consultation in terms of glycaemic control in the short term. However, more studies are required to investigate the long-term effects of telephone consultations and for those with HbA1c≥9%.