Potential Formula for the Calculation of Starting and Incremental Insulin Glargine Doses: ALOHA Subanalysis
BACKGROUND
Pragmatic methods for dose optimization are required for the successful basal management in daily clinical practice. To derive a useful formula for calculating recommended glargine doses, we analyzed data from the Add-on Lantus® to Oral Hypoglycemic Agents (ALOHA) study, a 24-week observation of Japanese type 2 diabetes patients.


METHODOLOGY/PRINCIPAL FINDINGS
The patients who initiated insulin glargine in basal-supported oral therapy (BOT) regimen (n = 3506) were analyzed. The correlations between average changes in glargine dose and HbA1c were calculated, and its regression formula was estimated from grouped data categorized by baseline HbA1c levels. Starting doses of the background-subgroup achieving the HbA1c target with a last-observed dose above the average were compared to an assumed optimal starting dose of 0.15 U/kg/day. The difference in regression lines between background-subgroups was examined. A formula for determining the optimal starting and titration doses was thereby derived. The correlation coefficient between changes in dose and HbA1c was -0.9043. The estimated regression line formula was -0.964 × change in HbA1c+2.000. A starting dose of 0.15 U/kg/day was applicable to all background-subgroups except for patients with retinopathy (0.120 U/kg/day) and/or with eGFR<60 mL/min/1.73 m(2) (0.114 U/kg/day). Additionally, women (0.135 U/kg/day) and patients with sulfonylureas (0.132 U/kg/day) received a slightly decreased starting dose.


CONCLUSIONS/SIGNIFICANCE
We suggest a simplified and pragmatic dose calculation formula for type 2 diabetes patients starting glargine BOT optimal daily dose at 24 weeks  =  starting dose (0.15×weight) + incremental dose (baseline HbA1c - target HbA1c+2). This formula should be further validated using other samples in a prospective follow-up, especially since several patient groups required lower starting doses.