Patients newly diagnosed with diabetes may have better long-term outcomes with immediate intensive glucose control, according to recent research.
Researchers performed a cohort study using the Kaiser Permanente Northern California Diabetes Registry to investigate whether early glycemic control appeared to affect diabetes complications and death after adjustment for demographic characteristics, risk factors, comorbid conditions, and HbA1c later in life. Outcome measures were incident advanced microvascular events (end-stage renal disease, diabetic eye disease, and lower-extremity amputation), macrovascular events (cerebrovascular disease, heart disease, heart failure, and vascular disease), and death. The study results were published Aug. 13 by Diabetes Care.
Overall, 34,737 patients with a new diagnosis of diabetes who survived for at least 10 years were included in the study. Average follow-up was 13.0 years, mean age at diagnosis was 56.8 years, and 46.7% of patients were women. Seven periods of early exposure to glycemic control were examined: 0 to 1 year, 0 to 2 years, 0 to 3 years, 0 to 4 years, 0 to 5 years, 0 to 6 years, and 0 to 7 years. Categories of HbA1c levels evaluated during these time periods were less than 6.5%, 6.5% to less than 7.0%, 7.0% to less than 8.0%, 8.0% to less than 9.0%, and 9.0% or greater.
Compared with HbA1c levels of less than 6.5% during the early exposure period of 0 to 1 year, HbA1c levels of 6.5% or greater were associated with increased risk for microvascular and macrovascular events, and HbA1c levels of 7.0% or greater were associated with increased risk for death. HbA1c levels of 9.0% or greater during the early exposure period of 0 to 4 years were associated with an increasing risk for macrovascular events. More time exposed to an HbA1c level of 8.0% or greater was associated with increased risk for microvascular events and death.
Based on their results, the authors concluded that a strong association exists between diabetes control in the first year after diagnosis and future risk for complications and death and that these risks, once established, may be irreversible. The authors cautioned that their results may not be generalizable to patients with established diabetes or those at high risk for death and that they could not establish causality, among other limitations.
“This study suggests that the legacy effect exists outside of trial populations, begins as early as the 1st year after diagnosis, and depends on the level of glycemic exposure,” the authors wrote. “These findings underscore the urgency of early diagnosis of diabetes and the future consequences of failing to achieve near-normal glycemia soon after patients are diagnosed with diabetes.”