Glycaemia control and the risk of hospitalisation for infection in patients with type 2 diabetes: Hong Kong Diabetes Registry.

Background: Infection occurs more commonly in diabetic patients compared with the general population and is an under-recognised but important morbidity in patients with diabetes. We examined the impact of glycaemic control on hospitalisation for infection in a large prospective cohort of Chinese adults with type 2 diabetes.
Methods: Between July 1994 and June 2014, 22 846 patients with type 2 diabetes underwent detailed assessment of metabolic control and diabetes complications. Patients were followed for occurrence of infection requiring hospitalisation as identified using discharge diagnosis codes.
Results: Over a median follow-up of 4.8 years, 20.3% of patients were hospitalised for any infection type, with respiratory tract, genitourinary tract, and skin being the most commonly affected sites. In multivariate Cox regression, time-dependent HbA1c was associated with all-site infection (hazard ratio [HR] 1.07 [95% confidence interval {CI}:1.05-1.09, P < 0.001]), genitourinary tract infection (HR 1.09 [95% CI: 1.04-1.14], P < 0.001), and skin infection (HR 1.16 [95% CI 1.12-1.21]. P < 0.001), but not infection of respiratory tract, and was independent of age, gender, disease duration, smoking, body mass index, glomerular filtration rate, haemoglobin, history of stroke, congestive heart failure, coronary heart disease, peripheral artery disease, diabetic neuropathy and cancer, and baseline drug use. Against an arbitrary HbA1c interval of >7.0-8.0% (53-64 mmol/mol), patients with HbA1c ≤6.0% (42 mmol/mol) and >8.0% (64 mmol/mol) had excess risks of infection-related hospitalisation adjusted for other factors.
Conclusions: In patients with type 2 diabetes, burden of serious infection is high. In the diabetic population, a U-shape relationship between glycaemia and infection-related hospitalisation was detected.
(Copyright © 2017 John Wiley & Sons, Ltd.)