RESUMO
AIMS: To evaluate an 18-month text-messaging intervention in teenagers with Type 1 diabetes and to assess factors associated with text responsiveness and glycaemic benefit. METHODS: Teenagers with diabetes (N = 147), aged 13-17 years, received two-way text reminders at self-selected times to check blood glucose levels and reply with blood glucose results. RESULTS: At baseline, the participants (48% boys, 78% white, 63% pump-treated) had a mean ± sd age of 14.9 ± 1.3 years, diabetes duration of 7.1 ± 3.9 years and HbA1c concentration of 69 ± 12 mmol/mol (8.5 ± 1.1%). The mean proportion of days with ≥1 blood glucose response declined over time (0-6 months, 60 ± 26% of days, 7-12 months, 53 ± 31% of days, 13-18 months, 43 ± 33% of days). Over 18 months, 49% responded with ≥1 blood glucose result on ≥50% of days (high responders). Regression analysis controlling for baseline HbA1c revealed no significant change in HbA1c from baseline to 18 months in high responders (P = 0.54) compared with a significant HbA1c increase in low responders (+0.3%, P = 0.01). In participants with baseline HbA1c ≥64 mmol/mol (≥8%), high responders were 2.5 times more likely than low responders to have a clinically significant [≥5.5 mmol/mol (≥0.5%)] HbA1c decrease over 18 months (P < 0.05). In participants with baseline HbA1c <64 mmol/mol(<8%), high responders were 5.7 times more likely than low responders to have an 18-month HbA1c <58 mmol/mol (<7.5%; P < 0.05). CONCLUSIONS: Teenagers with Type 1 diabetes who responded to text reminders on ≥50% of days over 18 months experienced clinically significant glycaemic benefit. There remains a need to tailor interventions to maintain teenager engagement and optimize improvements.