International Psychogeriatrics

Research Article

Comorbid cognitive impairment and depression is a significant predictor of poor outcomes in hip fracture rehabilitation

Liang Fenga1a2, Samuel C Scherera1a3, Boon Yeow Tana1a4, Gribson Chana4, Ngan Phoon Fonga1a5 and Tze Pin Nga1a2 c1

a1 Gerontological Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore

a2 Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore

a3 Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Australia

a4 St Luke's Hospital, Singapore, Singapore

a5 Department of Epidemiology and Public Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore

ABSTRACT

Background: The effects of depression and cognitive impairment on hip fracture rehabilitation outcomes are not well established. We aimed to evaluate the associations of depressive symptoms and cognitive impairment (individually and combined) with ambulatory, living activities and quality of life outcomes in hip fracture rehabilitation patients.

Methods: A cohort of 146 patients were assessed on depressive symptoms (Geriatric Depression Scale, GDS ≥ 5), cognitive impairment (Mini-mental State Examination, MMSE ≤ 23), and other variables at baseline, and on ambulatory status, Modified Barthel Index (MBI), and SF-12 PCS and MCS quality of life on follow ups at discharge, 6 months and 12 months post fracture.

Results: In these patients (mean age 70.8 years, SD 10.8), 7.5% had depressive symptoms alone, 28.8% had cognitive impairment alone, 50% had both, and 13.7% had neither (reference). Ambulatory status showed improvement over time in all mood and cognition groups ((β = 0.008, P = 0.0001). Patients who had cognitive impairment alone (β = −0.060, P = 0.001) and patients who had combined cognitive impairment with depressive symptoms β = −0.62, P = 0.0003), showed significantly less improvement in ambulatory status than reference patients. In the latter group, the relative differences in ambulatory scores from the reference group were disproportionately greater over time (β = −0.003, SE = 0.001, P = 0.021). Patients with combined depressive symptoms and cognitive impairment also showed a significantly lower MBI score, (β = −10.92, SE = 4.01, P = 0.007) and SF-12 MCS (β = −8.35, SE = 2.37, P = 0.0006). Mood and cognition status did not significantly predict mortality during the follow-up.

Conclusion: Depression and cognitive impairment comorbidity is common in hip fracture rehabilitation patients and significantly predicts poor functional and quality of life outcomes.

(Received May 14 2009)

(Revised June 18 2009)

(Revised September 21 2009)

(Accepted September 24 2009)

(Online publication December 02 2009)

Correspondence:

c1 Correspondence should be addressed to: Associate Professor Ng Tze Pin, Gerontological Research Program, National University of Singapore, Department of Psychological Medicine, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074. Phone: +65-67724514; Fax: +65-67772191. Email: pcmngtp@nus.edu.sg.