Visceral adiposity is not associated with inflammatory markers in trauma patients.

Background: Excess visceral adiposity induces chronic subclinical inflammation resulting in the metabolic syndrome. Whether excess visceral adiposity impacts posttraumatic inflammatory profiles more is unknown. We hypothesized that obese patients (body mass index >30 kg/m) with higher visceral to subcutaneous adipose tissue distribution would have increased inflammatory outcomes.

Methods: A secondary analysis of a prospective cohort of adult trauma patients requiring >48 hours of intensive care unit care over a 55-month period was analyzed. Body fat distribution was determined by radiologist review of computed tomography scans at L1. Concentric freeform regions were defined manually, and area was calculated. Visceral adiposity was defined as subcutaneous fat area: visceral area >1.35 (the median), whereas subcutaneous adiposity was defined as a ratio <1.35. Primary outcomes were proinflammatory biomarkers known to be associated with chronic visceral obesity (white blood cell count, interleukin 1, 2, 4, 6, 8, 10, and tumor necrosis factor alpha). Secondary outcomes were all-cause in-hospital mortality, adult respiratory distress syndrome, and nosocomial infections.

Results: Two hundred eighty-one (19%) obese patients with available computed tomography scans from 1,510 trauma patients were included. Visceral adiposity included 140 patients, subcutaneous adiposity included 141 patients. The two groups were similar in regards to age, Trauma Injury Severity Score, and Acute Physiology and Chronic Health Evaluation II score. There was no difference (p > 0.05) in proinflammatory biomarkers. Patients with visceral adiposity had similar clinical outcomes including mortality (p = 0.56), adult respiratory distress syndrome (p = 0.69), and infection (0.43).

Conclusions: Visceral body fat distribution in obese patients is not associated with increased inflammatory profiles or clinical outcomes after trauma. The impact of injury severity on acute inflammation likely overwhelms the metabolic disturbances and subclinical inflammation associated with visceral obesity in the chronic setting.