ORIGINAL ARTICLE In-hospital elderly mortality and associated factors in 12 Italian acute medical units: findings from an exploratory longitudinal study Elisa Ambrosi 1 • Stefano De Togni 2 • Annamaria Guarnier 1 • Paolo Barelli 1 • Paola Zambiasi 1 • Elisabetta Allegrini 3 • Letizia Bazoli 4 • Paola Casson 5 • Meri Marin 6 • Marisa Padovan 7 • Michele Picogna 8 • Patrizia Taddia 9 • Daniele Salmaso 10 • Paolo Chiari 11 • Tiziana Frison 12 • Oliva Marognolli 3 • Federica Canzan 3 • Luisa Saiani 13 • Alvisa Palese 14 Received: 29 March 2016 / Accepted: 13 April 2016 Ó Springer International Publishing Switzerland 2016 Abstract Background Given the progressive demographic ageing of the population and the National Health System reforms affecting care at the bedside, a periodic re-evaluation of in- hospital mortality rates and associated factors is recommended. Aims To describe the occurrence of in-hospital mortality among patients admitted to acute medical units and asso- ciated factors. Two hypotheses (H) were set as the basis of the study: patients have an increased likelihood to die H 1 : at the weekend when less nursing care is offered; H 2 : when they receive nursing care with a skill-mix in favour of Nursing Aides instead of Registered Nurses. Methods Secondary analysis of a prospective study of patients [ 65 years consecutively admitted in 12 Italian medical units. Data on individual and nursing care vari- ables were collected and its association with in-hospital mortality was analysed by stepwise logistic regression analysis. Results In-hospital mortality occurrence was 6.8 %, and 37 % of the patients died during the weekend. The logistic regression model explained 34.3 % (R 2 ) of the variance of in-hospital mortality: patients were six times (95 % CI = 3.632–10.794) more likely at risk of dying at week- ends; those with one or more AEDs admissions in the last 3 months were also at increased risk of dying (RR 1.360, 95 % CI = 1.024–1.806) as well as those receiving more care from family carers (RR = 1.017, 95 % CI = 1.009–1.025). At the nursing care level, those patient receiving less care by RNs at weekends were at increased risk of dying (RR = 2.236, 95 % CI = 1.270–3.937) while those receiving a higher skill-mix, thus indicating that more nursing care was offered by RNs instead of NAs were at less risk of dying (RR = 0.940, 95 % CI = 0.912–0.969). Conclusions Within the limitations of this secondary analysis, in addition to the role of some clinical factors, findings suggest redesigning acute care at weekends & Alvisa Palese alvisa.palese@uniud.it 1 Azienda per i Servizi Sanitari Trento, Via Alcide Degasperi 79, 38123 Trento, Italy 2 Azienda Ospedaliera Carlo Poma, Strada Lago Paiolo 10, 46100 Mantua, Italy 3 Azienda Ospedaliera Universitaria Integrata Verona, Piazzale Aristide Stefani 1, 37122 Verona, Italy 4 Fondazione Poliambulanza Istituto Ospedaliero, Via Leonida Bissolati 57, 25124 Brescia, Italy 5 Azienda ULSS 9 Treviso, Via Sant’Ambrogio di Fiera 37, 31100 Treviso, Italy 6 Azienda per l’Assistenza Sanitaria n. 2 Bassa Friulana- Isontina, Via Vittorio Veneto 174, 34170 Gorizia, Italy 7 Azienda ULSS n. 6 Vicenza, Viale Rodolfi 37, 36100 Vicenza, Italy 8 Azienda per l’Assistenza Sanitaria n.4 Friuli Centrale, Via Pozzuolo 330, 33100 Udine, Italy 9 Istituto Ortopedico Rizzoli, Via Alessandro Codivilla 9, 40136 Bologna, Italy 10 Fondazione Zancan, Via del Vescovado 66, 35141 Padua, Italy 11 Bologna University, Via Zamboni 33, 40126 Bologna, Italy 12 Azienda Ospedaliero-Universitaria, Via Giustiniani 2, 35128 Padua, Italy 13 Verona University, Via dell’Artigliere 8, 37129 Verona, Italy 14 Udine University, Viale Ungheria 20, 33100 Udine, Italy 123 Aging Clin Exp Res DOI 10.1007/s40520-016-0576-8