Introduction: Hip fracture is a major cause of morbidity and mortality in older people, particularly in those who have cognitive impairment; a high percentage of patients having hip fracture presented also with mental disorders (MD). Since surgery for the treatment of hip fractures is nowadays considered to be the gold standard even among nonagerian with a heavy co-morbidity burden, the study of association between surgery complications and MD appears to be of an overwhelming importance. In this paper we have studied whether hip fractured patients with MD develop more infections after hip surgery than patients with no MD.

Material and Methods: We have performed a multiple logistic regression model to study 912 patients operated on for a hip fracture. We have considered MD as the main variable to be verified with by statistical tests. Patients were classified within two groups: Group A (Patient operated on because hip fracture having a MD previously diagnosed) and Group B (Patients operated on because hip fracture not having MD). Data were analyzed by using a SPSS programme (14.0 version SPSS Inc., Chicago Illinois).

Results: Univariate analysis. NI developed in 58 patients (6,4%) out of 912 overall patients. Twelve out of 223 patients (5,38 %) were included in group A, whereas 46 of 689 (6,68 %) belonged to group B. Although patients with MD had less infections than patients without MD, there was not statistical differences (Odd ratio= 0,795; for Confidence Interval 96,5 % = 0,413–1,529; p=0,49). Multivariate analysis. MD was not associated to infection, either when in considering it alone (crude OR 0,79, CI of 95% = 0,41; 1,53; p=0,49) or in considering it together with the other variables, such as age, gender, and associated co-morbidities (multivariate analysis: adjusted OR 0,74, CI of 95% = 0,37;1,46; p=0,38).

Discussion and Conclusions: Since it could be thought that NI in patients with previous MD could be very high, bringing about the Discussion: of whether it is very risky or even worthy to operate on these patients, we have designed a cohort study in a group of patients with a former diagnosis of MD, who sustained a hip fracture and were operated on either by osteosynthesis or joint replacement. We have searched for infection as a complication of surgical treatment or hospital stay. Our results show that there was no association between MD and NI. Moreover multiple logistic analysis has shown that NI in MD patients is not associated to either age, gender or co-morbidities. Only age has been shown to be an independent variable of a higher risk for NI.