Risk factors for postoperative pneumonia in older adults aged ≥ 80 years with gastric cancer.

[BACKGROUND] In Japan, the proportion of elderly gastric cancer patients is increasing. Although surgery in patients aged ≥ 80 years is relatively safe, postoperative pneumonia often occurs, reducing quality of life and being fatal. We retrospectively investigated the risk factors for pneumonia after gastrectomy in elderly patients at our hospital.

[METHODS] Between 2010 and 2019, 113 patients aged ≥ 80 years underwent gastrectomy for gastric cancer at our hospital. Of these, 88 patients were retrospectively investigated, excluding 25 patients who did not receive sufficient postoperative follow-up. The diagnosis of pneumonia was based on chest CT findings. Univariate and multivariate analyzes for risk factors of pneumonia were performed using the Cox proportional hazards model.

[RESULTS] The patients were aged 80-93 years (median 83 years) and consisted of 63 males and 25 females. The surgical procedures included distal gastrectomy in 54, total gastrectomy in 25, proximal gastrectomy in two, and local resection in seven. Postoperative pneumonia was observed in 38 patients. Seventeen of them died from pneumonia. The time to onset of pneumonia was 0.2-144.6 months (median 12.0 months), and the median observation period for patients without pneumonia was 38.8 months. Multivariate analysis revealed that age, Geriatric Nutritional Risk Index, respiratory history, and extent of gastrectomy (total vs. distal: hazard ratio 3.91, 95% confidence interval 1.69-9.02) were independent pneumonia factors.

[CONCLUSIONS] In patients aged ≥ 80 years, age, low nutritional status, respiratory history, and total gastrectomy were risk factors for postoperative pneumonia.