The Relationship between Increases in Morning Spot Urinary Glucose Excretion and Decreases in HbA1Cin Patients with Type 2 Diabetes After Taking an SGLT2 Inhibitor: A Retrospective, Longitudinal Study.
BACKGROUND
Sodium glucose co-transporter 2 (SGLT2) inhibitors increase urinary glucose excretion (UGE) by reducing the renal threshold for glucose excretion, which results in decreased serum glucose concentrations in patients with type 2 diabetes mellitus (T2D). However, no study to date has determined whether larger increases in UGE after SGLT2 inhibitor treatment correspond to larger reductions in glycated hemoglobin (HbA1C).


METHODS
We enrolled participants who were newly prescribed an SGLT2 inhibitor (dapagliflozin 10 mg or ipragliflozin 50 mg, once daily) as an add-on therapy. Patients were tested for HbA1Cand first morning spot urinary-creatinine and -glucose concentrations immediately prior to administration of the SGLT2 inhibitor and at a 12-week follow-up appointment. We investigated the relationship between increases in morning spot UGE and decreases in HbA1C.


RESULTS
A total of 101 participants with T2D were enrolled. The median age and diabetes duration were 61.0 and 12.8 years, respectively, and the median HbA1Cwas 8.10%. SGLT2 inhibitors significantly lowered the HbA1Clevel, with a median change from baseline to week 12 of -0.60% (p < 0.001). Robust increases from baseline were seen for the morning spot urinary glucose-to-creatinine ratio (UGCR), with a median change at week 12 of 47.3 mg/mg. In the correlation analysis, the ∆HbA1Clevel showed a significant positive correlation with ∆morning spot UGCR (r = 0.395, p < 0.001). In other words, a greater reduction in HbA1Cwas correlated with a smaller increase in UGE. After adjusting for confounding variables, ∆HbA1Cwas significantly associated with ∆morning spot UGCR.


CONCLUSIONS
Although SGLT2 inhibitor treatment leads to a reduced HbA1Clevel by augmenting UGE, larger increases in UGE do not correlate to larger reductions in HbA1C. This suggests that the increase in UGE might not be an indicator of the degree of reductions in blood glucose.
Division of Endocrinology and Metabolism, Department of Internal Medicine, Graduate School, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.|Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.
So Ra
SR
Kim
Division of Endocrinology and Metabolism, Department of Internal Medicine, Graduate School, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea. yholee@yuhs.ac.|Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea. yholee@yuhs.ac.
Yong-Ho
YH
Lee
Division of Endocrinology and Metabolism, Department of Internal Medicine, Graduate School, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.|Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.
Eun Seok
ES
Kang
Division of Endocrinology and Metabolism, Department of Internal Medicine, Graduate School, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.|Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.
Bong-Soo
BS
Cha
Division of Endocrinology and Metabolism, Department of Internal Medicine, Graduate School, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea. bwanlee@yuhs.ac.|Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea. bwanlee@yuhs.ac.
Byung-Wan
BW
Lee
SGLT2 inhibitors; Sodium glucose co-transporter 2 inhibitors; Type 2 diabetes mellitus; Urinary glucose excretion; Urinary glucose-to-creatinine ratio