Prevalence of obesity and unrecognised glucose intolerance in a UK day-case surgery unit: Observational study

Abstract

The objectives of this study were: to determine the prevalence of overweight and obesity in a day-case surgery unit; to find out if obesity is more frequent than in the general population; and to assess glucose intolerance in obese day-case unit attendees. The study was conducted as a retrospective audit of prospectively collected observational data at a United Kingdom urban secondary care ambulatory surgery facility. The study participants comprised 829 (99.0%) patients with complete anthropometric records out of 837 undergoing preoperative assessment between April 2004 and June 2004. The main outcome measures were: prevalence of overweight and obesity according to body mass index (BMI) stratification; and glycosylated haernoglobin A1c (HbA1c), random venous plasma glucose, and prevalence of unrecognised glucose intolerance in obese patients. The results showed that 30.2% of 560 females had a BMI of 25-30kg/m2 (overweight), 19.1% 3G-40kg/m2 (class 1 and 2 obesity), and 2.5% over 40kg/m2 (class 3 obesity); 45.0%, 14.9% and 0.7% of 269 males, respectively, were in these categories. The mean HbA1c of obese patients was significantly elevated at 6.33% (95% confidence Interval 6.17-6.50%, p<0.001; non-diabetic reference range 4.0-6.0%). In all, 11.4% of 70 obese females and 20.8% of 24 obese males for whom a result was available showed an HbA1c greater than 7.0% suggesting unrecognised diabetes. The prevalence of obesity in the day-case surgery unit is similar to that of the local population. Obese ambulatory surgery patients exhibit markedly abnormal glucose tolerance. The yield of targeted opportunistic screening for diabetes is particularly high in this group with a number needed to screen of five for men and nine for women in order to detect one case likely to need pharmacological lntervention. Copyright © 2006 John Wiley & Sons.