Poorly controlled glycosylated haemoglobin (HbA1c) levels appear to aggravate the risk of mortality in patients with type 2 diabetes (T2D) and chronic kidney disease (CKD), a recent study has found. Glycaemic control is not associated with progression to end-stage kidney disease (ESKD).
The study included 4,543 patients (median age 67.6 years, 55.2 percent men) with a median HbA1c level of 7.1% at baseline. Of these, 2,692 participated in the trajectory analysis, each with a median of eight HbA1c measurements. Three trajectories were identified: nearly optimal (55.9 percent), moderate-to-stable (34.2 percent), and poorly controlled (9.9 percent).
Nearly optimal control was defined as having HbA1c stably below 7%, while those with moderate-to-stable control had levels fluctuating at approximately 8%. HbA1c levels in the poorly controlled group hovered at around 10%.
Cox proportional hazard analysis found that baseline HbA1c between 7–9% increased the risk of mortality nonsignificantly by 6 percent (hazard ratio [HR], 1.06, 95 percent confidence interval [CI], 0.95–1.18), an effect that worsened and reached statistical significance in those with baseline levels >9% (HR, 1.25, 95 percent CI, 1.07–1.46). Both risk estimates were calculated using those with HbA1c <7% as a reference.
Similarly, those with poor control vs nearly optimal HbA1c control were at a 35-percent greater risk of all-cause mortality (HR, 1.35, 95 percent CI, 1.06–1.71). No such effect was reported for patients who had moderate-to-stable control. Baseline levels or HbA1c trajectory were also unrelated to the risk of ESKD.