Preoperative Glycosylated Haemoglobin Screening to Identify Older Adult Patients with Undiagnosed Diabetes Mellitus-A Retrospective Cohort Study.

More than 25% of older adults in Europe have diabetes mellitus. It is estimated that 45% of patients with diabetes are currently undiagnosed, which is a known risk factor for perioperative morbidity. We investigated whether routine HbA1c screening in older adult patients undergoing surgery would identify patients with undiagnosed diabetes. We included patients aged ≥65 years without a diagnosis of diabetes who visited the preoperative assessment clinic at the Amsterdam University Medical Center and underwent HbA1c screening within three months before surgery. Patients undergoing cardiac surgery were excluded. We assessed the prevalence of undiagnosed diabetes (defined as HbA1c ≥ 48 mmol·mol-1) and prediabetes (HbA1c 39-47 mmol·mol-1). Using a multivariate regression model, we analysed the ability of HbA1c to predict days alive and at home within 30 days after surgery. From January to December 2019, we screened 2015 patients ≥65 years at our clinic. Of these, 697 patients without a diagnosis of diabetes underwent HbA1c screening. The prevalence of undiagnosed diabetes and prediabetes was 3.7% (95%CI 2.5-5.4%) and 42.9% (95%CI 39.2-46.7%), respectively. Preoperative HbA1c was not associated with days alive and at home within 30 days after surgery. In conclusion, we identified a small number of patients with undiagnosed diabetes and a high prevalence of prediabetes based on preoperative HbA1c screening in a cohort of older adults undergoing non-cardiac surgery. The relevance of prediabetes in the perioperative setting is unclear. Screening for HbA1c in older adult patients undergoing non-cardiac surgery does not appear to help predict postoperative outcome.

Comparison of Postoperative Neurocognitive Function in Older Adult Patients with and without Diabetes Mellitus.

INTRODUCTION: Delayed neurocognitive recovery (DNR; neurocognitive disorder up to 30 days postoperative) and postoperative neurocognitive disorders (POCD; neurocognitive disorder 1-12 months postoperative) occur frequently after surgery, with diabetes mellitus (DM) suggested to contribute to this. This was a single-center prospective cohort study. The main aim of this study was to investigate the role of DM and preoperative hemoglobin A1c (HbA1c) in the development of POCDs after noncardiac surgery. METHODS: Older adult patients ≥65 years of age scheduled for elective surgery were recruited. The Modified Telephone Interview for Cognitive Status questionnaire (TICS-M), a test of global cognitive functioning, was administered to determine cognition. Preoperative, 30-day postoperative, and 6-month postoperative cognition were compared for patients with and without DM. Cognitive decline was subdivided into mild (1 to 2 standard deviations below controls) and major (≥2 standard deviations below controls) DNR or POCD. Preoperative HbA1c levels were correlated with TICS-M scores. RESULTS: We analyzed 102 patients [median (IQR [range]) age 72.0 (5 [68-74])]), who were divided into patients with DM (80 patients [78%]) and patients without DM (22 patients [22%]). Baseline cognitive function was similar for both groups. Repeated measures ANOVA showed that mean DM patient TICS-M scores decreased 30 days postoperative (F(2, 200) = 4.0, p = 0.02), with subsequent recovery 6-month postoperative, compared to stable TICS-M scores in non-DM patients. There were significantly more DM patients with DNR than non-DM patients (n = 11 [50%] vs. n = 14 [17.5%]; p = 0.031). There were no between-group differences in mild or major POCD. Higher preoperative HbA1c levels were significantly correlated with decreased 30-day Δcognition scores (F(1, 54) = 9.4, p = 0.003) with an R2 of 0.149 (ß -0.45, 95% confidence interval: -0.735 to -0.154). CONCLUSIONS: Older adult patients with DM undergoing surgery have an increased risk of DNR compared to older adult non-DM patients, but no increased risk of POCD. In DM patients, higher preoperative HbA1c levels were associated with an increased risk of DNR.

Type 1 and other types of diabetes mellitus in the perioperative period. What the anaesthetist should know.

Diabetes mellitus is often treated as a uniform disease in the perioperative period. Type 2 diabetes is most commonly encountered, and only a minority of surgical patients have been diagnosed with another type of diabetes. Patients with a specific type of diabetes can be particularly prone to perioperative glycaemic dysregulation. In addition, certain type-related features and pitfalls should be taken into account in the operating theatre. In this narrative review, we discuss characteristics of types of diabetes other than type 2 diabetes relevant to the anaesthetist, based on available literature and data from our clinic.