Background: Pneumonia causes more deaths than any other infectious disease, especially in older patients with multiple chronic diseases. Recent studies identified a low functional status as prognostic factor for mortality in elderly patients with pneumonia while contrasting data are available about the role of diabetes. The aim of this study was to evaluate the in-hospital, 3-month and 1-year mortality in elderly subjects affected by pneumonia enrolled in the RePoSi register.Methods: We retrospectively analyzed the data collected on hospitalized elderly patients in the frame of the REPOSI project. We analyzed the socio-demographic, laboratory and clinical characteristics of subjects with pneumonia. Multivariate logistic analysis was used to explore the relationship between variables and mortality.Results: Among 4714 patients 284 had pneumonia. 52.8% were males and the mean age was 80 years old. 19.8% of these patients had a Barthel Index <= 40 (p < 0.0001), as well as 43.2% had a short blessed test >= 10 (p < 0.0117). In these subjects a significant CIRS for the evaluation of severity and comorbidity indexes (p < 0.0001) were present. Although a higher fasting glucose level was identified in people with pneumonia, in the multivariate logistic analysis diabetes was not independently associated with in-hospital, 3-month and 1-year mortality, whereas patients with lower Barthel Index had a higher mortality risk (odds ratio being 9.45, 6.84, 19.55 in hospital, at 3 and 12 months).Conclusion: Elderly hospitalized patients affected by pneumonia with a clinically significant disability had a higher mortality risk while diabetes does not represent an important determinant of short and long-term outcome.