Assessing quality of life by EQ-5D among Chinese elderly with cognitive function impairment: Findings from SCOBHI pilot

The quality of life among the elderly with cognitive function impairment has been rarely studied in the Chinese population. The EuroQol-5D system (EQ-5D) is a standardized instrument to assess the health-related quality of life. We report the performance of the EQ-5D in a cross-sectional study in Shanghai, China, comparing cases of dementia with cases of MCI and normal controls. An age- and sex-matched sample of 34 dementia patients, 34 MCI patients and 32 normal controls (mean age =74.0, 49% female) was recruited into the SCOBHI pilot study. Proxies of study subjects were administered the EQ-5D. The EQ-5D describes health status according to five dimensions: mobility, pain/discomfort, self-care, anxiety/depression, and usual activities. Each dimension has three levels, namely, “no problems”, “some problems”, and “severe problems”. It also consists of a visual analogue scale (VAS) ranging from 0 (worst imaginable health state) to 100 (best imaginable health state). Trend chi-square test was used to detect the association between the severity of cognitive function impairment and problems in EQ-5D dimensions. One-way ANOVA was used to compare the means of VAS among subjects in 3 study groups. Most proxies (96%) were spouses and children of study subjects. For the dimension of “self-care”, 27% of dementia patients had problems, whereas none of MCI and control subjects had problems (trend p<0.001). For the dimension of “usual activities”, the percentage of subjects who had problems in dementia, MCI and control groups were 97%, 97% and 84%, respectively (trend p=0.049). Dementia patients had the significantly worst health state (mean VAS=51±24) compared with that of MCI (mean VAS=85±15) and control subjects (mean VAS=95±10) (p<0.001). There's no significant relation between severity of cognitive function impairment and problems in EQ-5D dimensions of “mobility”, “pain/discomfort”, and “anxiety/depression”. We found a significant association between the severity of cognitive function impairment and problems in “self-care” and “usual activities” of EQ-5D dimensions and VAS. Cognitive function impairment did not affect other aspects of quality of life among the Chinese elderly.