Background: There are no studies of autonomic function comparing Alzheimer's disease (AD), vascular dementia (VAD), dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Aims: To assess cardiovascular autonomic function in 39 patients with AD, 30 with VAD, 30 with DLB, 40 with PDD and 38 elderly controls by Ewing's battery of autonomic function tests and power spectral analysis of heart rate variability. To determine the prevalence of orthostatic hypotension and autonomic neuropathies by Ewing's classification. Results: There were significant differences in severity of cardiovascular autonomic dysfunction between the four types of dementia. PDD and DLB had considerable dysfunction. VAD showed limited evidence of autonomic dysfunction and in AD, apart from orthostatic hypotension, autonomic functions were relatively unimpaired. PDD showed consistent impairment of both parasympathetic and sympathetic function tests in comparison with controls (all p,0.001) and AD (all p,0.03). DLB showed impairment of parasympathetic function (all p,0.05) and one of the sympathetic tests in comparison with controls (orthostasis; p = 0.02). PDD had significantly more impairment than DLB in some autonomic parameters (Valsalva ratio: p = 0.024; response to isometric exercise: p = 0.002). Patients with VAD showed impairment in two parasympathetic tests (orthostasis: p = 0.02; Valsalva ratio: p = 0.08) and one sympathetic test (orthostasis: p = 0.04). These results were in contrast with AD patients who only showed impairment in one sympathetic response (orthostasis: p = 0.004). The prevalence of orthostatic hypotension and autonomic neuropathies was higher in all dementias than in controls (all p,0.05). Conclusion: Autonomic dysfunction occurs in all common dementias but is especially prominent in PDD with important treatment implications.

Qualitative studies suggest that patients with primary biliary cirrhosis (PBC) experience significant problems with memory and concentration. Studies of nonhepatic disease have linked hypotension and cognitive impairment. In this study, we determined the prevalence of cognitive symptoms in PBC, examined the relationship between symptoms and overt cognitive impairment and structural brain lesions, and explored the role of autonomic dysfunction. The prevalence of cognitive symptoms was determined in 198 patients with PBC. Twenty-eight representative early-stage female patients with PBC and 11 matched controls underwent formal cognitive testing at baseline and after 2 years of follow-up. Autonomic nervous system function was assessed according to heart rate variability and baroreflex sensitivity. Eleven subjects with PBC had structural brain lesions quantified via magnetic resonance imaging. Cognitive symptoms were frequent in our PBC population, with 53% of patients experiencing moderate or severe problems with concentration and/or memory, which were unrelated in their severity to biochemical and histological makers of liver disease severity, suggesting that this symptom burden is largely or entirely unrelated to hepatic encephalopathy. Perceived cognitive symptoms correlated with objectively assessed cognitive impairment (r 2 ‫؍‬ 0.2, P < 0.05). Cognitive deficits were seen in the PBC cohort compared with controls, with significant decline detected over 2 years of follow-up. Correlations were seen between cognitive performance (full-scale intelligence quotient) and systolic blood pressure (P ‫؍‬ 0.01, r 2 ‫؍‬ 0.2) with decline in cognitive function associated with autonomic abnormalities. Structural brain lesions were found in PBC, the density of which correlated with degree of cognitive impairment (P ‫؍‬ 0.01, r 2 ‫؍‬ 0.5) and autonomic function (P ‫؍‬ 0.03, r 2 ‫؍‬ 0.2). Conclusion: Cognitive symptoms are prevalent in PBC independent of liver disease severity and are associated with poorer performance on objective cognitive testing. Cognitive impairment is, in turn, associated with structural brain lesions and autonomic dysfunction, which may predict risk of cognitive decline. (HEPATOLOGY 2008;48:541-549.) P rimary biliary cirrhosis (PBC) is a chronic cholestatic liver disease with an autoimmune etiology. 1 In addition to the risk of progressive liver disease, culminating in biliary cirrhosis with its associated complications, patients frequently experience non-stage-associated symptoms that can often lead to significant impairment of their quality of life. [2][3][4][5][6] Research into the non-end-stage disease-associated factors that lead to impairment of quality of life in PBC has, to date, largely focused on fatigue; a symptom which affects a significant proportion of patients and which is associated with impairment in normal physical functioning. 7-10 However, patient reports, and qualitative studies performed in the derivation of a PBC-specific quality of life measure, the PBC-40, suggest the existence of...

The prevalence of autonomic dysfunction in primary biliary cirrhosis patients is significantly higher than has previously been thought to be the case. Indeed, when sensitive detection modalities are used, it is found to be almost universal at all stages of the disease process. Fatigue in primary biliary cirrhosis is associated with abnormalities of autonomic function.

pSS patients have impaired blood pressure response to standing. Dysautonomia correlates with PSS-associated symptoms and quality of life.