The Influence of Cognitive Function on Outcome After a Hip Fracture

BACKGROUND: Previous studies have indicated that patients with a hip fracture who have impaired cognitive function have an increased risk for complications, poor long-term outcome, and an increased mortality rate. An assessment of cognitive function is often lacking in nursing and medical records. We investigated whether an assessment of cognitive function obtained with use of a validated instrument would be a useful patient management adjunct. METHODS: We studied 213 patients with a hip fracture who had a mean age of eighty-four years and were entered in a prospective trial with a follow-up evaluation at four and twelve months. On admission to the orthopaedic ward, the patients were evaluated with use of the Short Portable Mental Status Questionnaire to assess their cognitive function. The outcome for patients with severe cognitive dysfunction, i.e., those with a score of <3 on the questionnaire, was compared with the outcome for patients with higher scores. The main outcome measurements were the Charnley hip score, activities of daily living status, health-related quality of life, and mortality. RESULTS: A Short Portable Mental Status Questionnaire score of <3 and male gender were associated with an increased mortality rate during the first twelve months. Moreover, patients with a score of <3 had a significantly worse outcome with regard to the ability to walk and to perform the activities of daily living, with 36% of these patients confined to a wheelchair and almost 39% totally dependent with regard to daily living functions at the time of the final follow-up (p < 0.001). CONCLUSIONS: The systematic use of the Short Portable Mental Status Questionnaire upon admission to the orthopaedic ward identifies patients with a hip fracture who have severe cognitive dysfunction and effectively predicts their outcome with regard to the ability to walk, ability to perform the activities of daily living, and mortality, and it can be recommended for use in the care of elderly patients with a hip fracture.