High Prevalence of Undiagnosed Dysglycemia in Surgical Patients Linked to Poor Outcomes: JAMA
According to a new study, dysglycemia commonly present among general surgery patients independently increases risks of complications, readmissions, and mortality. Further, many patients had diabetes-range HbA1c levels without a prior diagnosis, supporting the need for routine preoperative HbA1c screening and personalized glycemic management to improve surgical outcomes. The study was published in JAMA Surgery by Thomas S. and colleagues.
Dysglycemia, identified as abnormal blood glucose levels including hyperglycemia and diabetes, is increasingly recognized as a major risk factor for poor surgical outcomes; however, its screening with HbA1c is not traditionally performed in many surgical settings. This large-scale analysis was conducted to provide clarification on the clinical utility of preoperative HbA1c measurement for assessing postoperative risks and diagnosing undetected cases of diabetes.
The following retrospective cohort study used data from the American College of Surgeons NSQIP from 2021 to 2023; it comprises data from over 700 hospitals worldwide, the majority of which are based in the United States. This was a retrospective study of 282,131 adult patients with a mean age of 60 years undergoing various general surgical procedures. Participants were stratified by glycemic status, which was determined using a documented diagnosis of diabetes combined with HbA1c levels. HbA1c values were categorized in ranges that reflected glycemic control-from near normal (<6.0%) to very poor control (>9.0%). Patients with an HbA1c level greater than 6.4% without a previous diagnosis of diabetes were considered to have undiagnosed diabetes.
Key Findings
The study highlighted several important findings that demonstrate the impact of preoperative glycemic control on surgical outcomes:
Among the 282,131 patients, 36% were diagnosed with diabetes, whereas 6.4% had HbA1c within the diabetic range without prior diagnosis, indicative of undiagnosed diabetes.
Among patients with diagnosed diabetes, the risk of any postoperative complication increased progressively with worsening glycemic control:
Near-normal HbA1c (<6.0%): OR 1.06 (95% CI, 1.00–1.11)
Very poor control (>9.0%): OR 1.32 (95% CI, 1.25–1.39)
Patients with undiagnosed diabetes also showed significantly higher risks of adverse outcomes, including:
Medical complications: OR 1.11 (95% CI, 1.04–1.18)
Mortality: OR 1.24 (95% CI, 1.07–1.42)
High HbA1c was also related to higher rates of readmission to the hospital and reoperation within 30 days following surgery.
This large multicenter study found that dysglycemia-both diagnosed and undiagnosed-is highly prevalent among general surgery patients and independently associated with higher risks of complications, readmissions, and mortality within 30 days after surgery. These findings strongly support routine preoperative HbA1c screening as part of standard surgical evaluation.
Reference:
Schaschinger T, Niederegger T, Brandt J, et al. Preoperative Hemoglobin A1C, Glycemic Status, and Postoperative Outcomes in General Surgery. JAMA Surg. Published online November 05, 2025. doi:10.1001/jamasurg.2025.4706
