Obese patients with diabetes, hypertension have increased risk of complications after surgery
MedWire News: Obese patients with hypertension and diabetes are at substantially increased risk for major complications following noncardiac surgery, say researchers.
Obesity has previously been shown to be paradoxically associated with a lower risk of mortality after noncardiac surgery, but whether this risk differs between metabolically healthy obese patients and obese patients with the metabolic syndrome is currently unknown.
To investigate, Laurent Glance (University of Rochester Medical Center, New York, US) and colleagues identified 310,208 patients who underwent general, vascular, or orthopedic surgery between 2005 and 2007.
Obese patients (body mass index [BMI] ≥30 kg/m2) were divided into two groups: those who were metabolically healthy and those who had additional risk factors related to the metabolic syndrome, specifically, diabetes and hypertension.
Overall, metabolic syndrome risk factors were present in 6.7% of patients, of whom 62.8% were obese, 25.7% morbidly obese (BMI 40-49.9 kg/m2), and 11.5% super obese (BMI ≥50 kg/m2).
Compared with patients who were of normal weight (BMI 18.5-24.9 kg/m2), those with the metabolic syndrome who were obese, morbidly obese, or super obese had a 1.70- 2.01-, and 2.66-fold increased risk for adverse cardiac events, respectively. In addition, risk for mortality was increased two fold among the super obese.
Obese patients with the metabolic syndrome were also between 1.5 and 2.5 times more likely to suffer from pulmonary complications, two times more likely to suffer from neurologic complications, and three to seven times more likely to suffer from acute kidney injury, compared with their metabolically normal, normal-weight peers.
"Given the high prevalence of obesity in the United States, our findings may have important implications for risk stratification and the peri-operative management of obese patients with the metabolic syndrome," say the researchers.
Writing in the journal Anesthesiology, Glance et al explain that they have identified a subpopulation of "metabolically obese" patients with a dramatically higher risk for complications after undergoing noncardiac surgery than their metabolically healthy counterparts.
The team concludes that by identifying this very high-risk group of patients, they now have the opportunity to explore approaches that may further drive public health efforts to control the obesity epidemic.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Nikki Withers