AIM:Cardiovascular autonomic and peripheral sensoryneuropathy is a known complication of chronic alcoholicand non-alcoholic liver diseases.We aimed to assess theprevalence and risk factors for peripheral sensory nerveand autonomic dysfunction using sensitive methods inpatients with primary biliary cirrhosis (PBC).METHODS:Twenty-four AMA M2 positive female patientswith clinical,biochemical and histological evidence of PBCand 20 age matched healthy female subjects were studied.Five standard cardiovascular reflex tests and 2d-h heartrate variability(HRV)analysis were performed to defineautonomic function.Peripheral sensory nerve function onmedian and peroneal nerves was characterized by currentperception threshold(CPT),measured by a neuroselectivediagnostic stimulator(Neurotron,Baltimore,MD).RESULTS:Fourteen of 24 patients(58%)had at least oneabnormal cardiovascular reflex test and thirteen(54%)had peripheral sensory neuropathy.Lower heart rateresponse to deep breathing(P=0.001),standing(P=0.03)and Valsalva manoeuvre(P=0.01),and more profounddecrease of blood pressure after standing(P=0.03)wasfound in PBC patients than in controls.As a novel findingwe proved that both time domain and frequency domainparameters of 24-h HRV were significantly reduced in PBCpatients compared to controls.Each patient had at leastone abnormal parameter of HRV.Lower CPT values indicatedhyperaesthesia as a characteristic feature at peronealnerve testing at three frequencies(2000 Hz:P=0.005;250 Hz:P=0.002;5 Hz:P=0.004)in PBC compared tocontrols.Correlation of autonomic dysfunction with theseverity and duration of the disease was observed.Lowertotal power of HRV correlated with lower CPT values atmedian nerve testing at 250 Hz(P=0.0001)and at 5 Hz(P=0.002),as well as with those at peroneal nerve testingat 2000 Hz(P=0.01).CONCLUSION:Autonomic and sensory nerve dysfunctionsare frequent in PBC.Twenty-four-hour HRV analysis is moresensitive than standard cardiovascular tests for detectingof both parasympathetic and sympathetic impairments.Ournovel data suggest that hyperaesthesia is a characteristicfeature of peripheral sensory neuropathy and mightcontribute to itching in PBC.Autonomic dysfunction is relatedto the duration and severity of PBC. AIM: Cardiovascular autonomic and peripheral sensory neuropathy is a known complication of chronic alcoholic and non-alcoholic liver diseases.We aimed to assess theprevalence and risk factors for peripheral sensory nerve and autonomic dysfunction using sensitive methods inpatients with primary biliary cirrhosis (PBC) .METHODS: Twenty- four AMA M2 positive female patients with clinical, biochemical and histological evidence of PBCand 20 age matched healthy female subjects were studied. Fied standard cardiovascular reflex tests and 2d-h heart rate variability (HRV) analysis were performed to defineautonomic function. Peripheral sensory nerve function onmedian and Fourteen of 24 patients (58%) had at least one cardiovascular symposia and reflex test (13%) had peripheral sensory neuropathy.Lower heart rateresponse to deep breathing (P = 0.001), standing ( P = 0.03) and Valsalva manoeuvre (P = 0.01), and more profoundcrecrease of blood pressure after standing (P = 0.03) wasfound in PBC patients than in controls. As a novel findingwe proved that both time domain and frequency domainparameters of 24-h HRV were significantly reduced in PBCpatients compared to controls. Each patient had at leastone abnormal parameter of HRV.Lower CPT values ​​indicated hyperaesthesia as a characteristic feature at peronealnerve testing at three frequencies (2000 Hz: P = 0.005; 250 Hz: P = 0.002; 5 Hz: P = 0.004) in PBC compared tocontrols. Correlation of autonomic dysfunction with theseverity and duration of the disease was observed. Lowertotal power of HRV correlated with lower CPT values ​​atmedian nerve testing at 250 Hz (P = 0.0001) and at 5 Hz ( P = 0.002), as well as with at peroneal nerve testingat 2000 Hz (P = 0.01). CONCLUSION: Autonomic and sensory nerve dysfunctionsare frequent in PBC.Twenty-four-hour HRV analysis is moresensitive than standard cardiovascular tests for detecting of both parasympathetic and sympathetic impairments. Turnovel data suggest that hyperaesthesia is a characteristic feature of peripheral sensory neuropathy and mightcontribute to itching in PBC. Autonomic dysfunction is related to the duration and severity of PBC.