Incidence of cerebrovascular lesions in pure autonomic failure

In pure autonomic failure (PAF) - a rare form of primary dysautonomia - some patients show cerebrovascular lesions usually found in hypertensive subjects. In an autonomic laboratory records of patients with a definitive diagnosis of PAF having had cerebral imaging (cMRI, cCT) were analysed retrospectively. Tilt table data (supine/tilted), 24 hour blood pressure recordings (day/night) and serum catecholamine levels were correlated with cerebrovascular lesions and also compared to published normal values. 50 PAF patients (23 female, 27 male) were identified, mean age 67 years (sd 9.5). Out of these 35 (70%) had pathologic cerebral scans showing white matter lesions (WML) in 30, lacunar strokes in 5 and hemispheric stroke and microbleeds each in 1. Age and supine systolic blood pressure were significantly elevated in patients with pathologic scans (70 compared to 61 years [p=0.007], and 170 compared to 154 mmHg [p=0.045]). Out of 28 patients with WML and ambulatory blood pressure recordings available 24 were non-dippers. The data show that the frequency of WML is lower in PAF patients aged 60 to 80 years compared to age matched community based samples. Although PAF usually results in hypotension, a frequent complication is supine hypertension. Although the overall frequency of WML seems to be reduced in PAF, a number of patients with elevated supine systolic blood pressure (>160 mmHg) develop WML and some of these suffer stroke.