Nonalcoholic steatohepatitis in bariatric patients with a diagnosis of obstructive sleep apnea

Abstract

Objective: To study a possible association between obstructive sleep apnea (OSA) severity, managed with noninvasive ventilation, and nonalcoholic steatohepatitis (NASH) in bariatric surgical patients.

Methods: Medical records of 218 bariatric surgical patients who underwent liver biopsy were reviewed. OSA severity was determined from preoperative polysomnography (apnea-hypopnea index (AHI) ≤ 15 no/mild OSA vs. AHI ≥ 16 moderate/severe OSA). Patients diagnosed with OSA were prescribed noninvasive ventilation. Patients were categorized according to liver histopathology into 3 groups: (i) no liver disease or simple steatosis, (ii) mild NASH (steatosis with necroinflammation and mild fibrosis (stage 0-1)), and iii) advanced NASH (steatosis with necroinflammation and more advanced fibrosis (stage ≥ 2)).

Results: 125 patients (57%) had no/mild OSA, and 93 (43%) had moderate/severe OSA. There was no difference in serum aminotransferases between patients by OSA severity classification. There was a high prevalence of hepatic histopathological abnormalities: 84% patients had steatosis, 57% had necroinflammation, 34% had fibrotic changes, and 14% had advanced NASH. There was no association between severity of NASH and severity of OSA.

Conclusions: There is no association between stage of steatohepatitis and OSA severity among morbidly obese patients managed with noninvasive ventilation.

Fig. 1

Liver biopsy specimen (Masson's trichrome stain, × 100) showing macrovesicular steatosis, diffuse hepatocyte ballooning (HB) and rare Mallory's hyaline bodies (MB). Periportal inflammation and fibrosis suggest cirrhotic changes in liver parenchyma. These histopathological changes are consistent with advanced NASH.