BACKGROUND: Patients undergoing laparoscopic paraesophageal hernia (PEH) repair risk substantial morbidity. The aim of the present study was to analyze predictive factors for postoperative morbidity and mortality. METHODS: A total of 354 laparoscopic PEH repairs were analyzed from the database of the Swiss Association for Laparoscopic and Thoracoscopic Surgery (SALTS). Age (<70 and >/=70 years) and risk (low: American Society of Anesthesiologists (ASA) scores 1 + 2; high ASA scores 3 + 4) groups were defined and multivariate logistic regression was conducted. RESULTS: In patients >/=70 years of age postoperative morbidity (24.4% versus 10.1%; p = 0.001) and mortality (2.4% versus 0%; p = 0.045) were significantly higher than in patients <70 years of age. In patients with gastropexy, this significant age difference was again present (38.8% versus 10.5%; p = 0.001) whereas in patients with fundoplication no difference between age groups occurred (11.9% versus 10.1%; p = 0.65). Mortality did not differ. High-risk patients had a significantly higher morbidity (26.0% versus 11.2%; p = 0.001) but not mortality (2.1% versus 0.4%; p = 0.18). The multivariate logistic regression identified the following variables as influencing postoperative morbidity: Age >/=70 years (Odds Ratio [OR] 1.99 [95% CI 1.06 to 3.74], p = 0.033); ASA 3 + 4 (OR 2.29 [95% Confidence Interval (CI) 1.22 to 4.3]; p = 0.010); type of operation (gastropexy) (OR 2.36 [95% CI 1.27 to 4.37]; p = 0.006). CONCLUSIONS: In patients undergoing laparoscopic paraesophageal hernia repair age, ASA score, and type of operation significantly influence postoperative morbidity and mortality. Morbidity is substantial among elderly patients and those with co-morbidity, questioning the paradigm for surgery in all patients. The indication for surgery must be carefully balanced against the individual patient's co-morbidities, age, and symptoms, and the potentially life threatening complications.