Orthostatic hypotension, hypotension and cognitive status: early comorbid markers of primary dementia?

OBJECTIVE

Few studies have explored the relationship between orthostatic hypotension (OH) and cognition. The aim of this study was to examine the association of OH with cognitive impairment and decline in a cohort of Chinese elderly, and its effect modification by blood pressure (BP) status at baseline.

METHOD

Among 2,321 community-living older adults, free of cardiovascular disease and stroke, baseline BP measurements were used to determine the presence of OH and categorize participants as hypotensives, normotensives or hypertensives. The Mini-Mental State Examination (MMSE) was used to assess cognitive impairment (MMSE score <24). Cognitive decline (decrease in MMSE score by > or =1) was assessed from 1 to 2 years of follow-up for 1,347 participants without baseline cognitive impairment.

RESULTS

Mean age of the subjects was 65.5 years and 381 (16.6%) showed OH. OH was not associated with cognitive impairment overall. However, among hypotensives, OH increased the odds of cognitive impairment (OR = 4.1, 95% CI = 1.11-15.1), while hypertensives with OH showed reduced odds of cognitive impairment (OR = 0.48, 95% CI = 0.26-0.90). Among cognitively intact participants, OH was not associated with cognitive decline overall or in BP subgroups.

CONCLUSION

The increased risk of cognitive impairment in hypotensives with OH suggests that hypotension with OH may be an early comorbid marker of a primary incipient dementia.