[Survey of comorbidities for hospitalized patients with cognitive disorders]

To provide rationales for the prevention and treatment of elderly patients with cognitive disorders through comparing the comorbidities according to different etiologies and severities.

Six groups of different cognitive status were selected. There were 438 normal cognitive subjects (NC) from Jing'an community of Shanghai. Five other groups were from the Memory Clinic at our hospital from June 2006 to June 2010. There were subjective memory complaints (n = 443, SMC), mild cognitive impairment (n = 540, MCI), vascular cognitive impairment-non dementia (n = 119, VCI-ND), Alzheimer's disease (n = 337, AD) and vascular dementia (n = 54, VaD). All participants finished a battery of neuropsychological tests and completed the survey of such comorbidities as stroke, conscious disturbance, hypertension, diabetes, head injuries and excessive drinking.

The comorbidity rates of diabetes were 11.4%, 9.9%, 16.1%, 14.2%, 12.4% and 18.5% in 6 groups (NC, SMC, MCI, VCI-ND, AD, VaD) respectively. There were no differences for overall or pairwise chi square tests. The rates of stroke, hypertension and excessive drinking in patients of VCI-ND and VaD were higher than those of SMC, MCI and AD. The comorbidity rates in the VCI-ND and VaD group were 54.6% vs 62.9% for stroke; 61.3% vs 79.6% for hypertension; 22.6% vs 37.0% for excessive drinking. Whereas in the SMC, MCI and AD groups, the rates were 9.4%, 10.9% and 3.0% for stroke; 44.9%, 47.2% and 42.1% for hypertension; 18.0%, 18.3% and 15.1% for excessive drinking. No distinct differences existed for the comorbidity rates among SMC, MCI and AD groups or among different degrees of AD.

Etiologies rather than severities determine the different rates of comorbidities in the elders with cognitive impairment.