Comparative effectiveness of sitagliptin vs sulphonylureas in older people

Background two common anti-diabetic treatments used are sitagliptin and sulphonylureas however evidence examining their comparative effectiveness in older people is limited. Objective to evaluate effectiveness of sitagliptin vs sulphonylureas when added to metformin in older (aged ≥75) vs younger people (18–75). Design retrospective cohort study. Setting UK Primary Care. Subjects 2,904 individuals prescribed sitagliptin (223 aged≥75) and 13,683 prescribed sulphonylureas (1,725 aged ≥75). Methods multivariable regression to analyse difference in HbA1c and weight, 12 months after add-on initiation and proportion achieving different glycaemic targets. Results after multivariate adjustment to remove baseline differences, the HbA1c after 12 months of treatment was on average 1 mmol/mol (95%CI −0.7 to 2.8) higher with sitagliptin vs sulphonylureas in older people though this was not statistically significant. The weight however, was significantly lower −1.4 kg (95%CI −2.1 to −0.7) with sitagliptin vs sulphonylureas. A lower proportion prescribed sitagliptin vs sulphonylureas recorded HbA1c < 48 mmol/mol by study end: Odds Ratio 0.63 (95%CI 0.42–0.95). In younger people, similar HbA1c reductions were also observed with both treatments, however weight after 12 months was even lower with sitagliptin vs sulphonylureas: −2.3 kg (95%CI −2.5 to −2.0). Conclusions similar HbA1c reduction was observed when sitagliptin or sulphonylureas were added to metformin in older and younger age-groups. Sitagliptin use led to modest comparative weight loss. There may be greater risk of over-treatment with sulphonylureas evidenced by greater proportion recording HbA1c < 48 mmol/mol by study end. This evidence supporting use of sitagliptin when add-on therapy is selected in older adults should be considered alongside the wider evidence-base and patient-preference.