The Study On The Autonomic Function In Patients With Narcolepsy Type 1 During Wakefulness

Objective:To study autonomic dysfunction in patients with narcolepsy type 1 during wakefulness and the relationship between cerebrospinal fluid hypocretin-1 levels and autonomic dysfunction.Method:In this study,we collected 25 patients with narcolepsy type 1(NT1)who visited the Neurological Sleep Center of the First Hospital of Jilin University between January 2022 and February 2023.20 healthy individuals matched for gender,age,and body mass index(BMI)were selected as control group.All subjects were evaluated for autonomic function using the Scale for Assessment of Autonomic Function in Parkinson’s Disease(SCOPA-AUT),heart rate variability(HRV),plasma catecholamine and metabolite assays.The data were analyzed to compare autonomic function between the two groups and the correlation between cerebrospinal fluid hypocretin-1 levels and autonomic dysfunction in patients with NT1.Results:1.Patients with NT1 had significantly higher Epworth sleeping scale(ESS)scores than control group(15.32±3.75 vs.4.45±1.43,P<0.001).Patients with NT1 had significantly higher SCOPA-AUT scores than control group [8.00(6.00,14.00)vs.4.00(2.00,7.50),P<0.05].The digestive system score was significantly higher in patients with NT1 than controls [3.00(1.00,4.00)vs.1.00(0.00,2.00),P<0.05].The urinary system score was significantly higher in patients with NT1 than controls [2.00(1.00,4.00)vs.0.00(0.00,1.00),P<0.05].The cardiovascular system score was significantly higher in patients with NT1 than controls [1.00(0.00,2.00)vs.0.00(0.00,1.00),P<0.05].The sexual function score was significantly higher in patients with NT1 than controls [0.00(0.00,0.50)vs.0.00(0.00,0.00),P<0.05].2.Compared with control group,patients with NT1 had longer total sleep time(458.81 ±100.19 min vs.390.80±33.02 min,P < 0.05),increased N1% [22.10(15.95,38.40)% vs.4.50(3.28,5.50)%,P < 0.001],decreased N2% [40.20(31.65,46.80)% vs.53.45(45.33,58.23)%,P< 0.05] and decreased N3% [15.00(8.60,19.30)% vs.20.45(16.60,25.05)%,P<0.05].Compared with control group,patients with NT1 had shorter REM sleep latency[58.50(4.25,88.00)min vs.105.00(92.50,117.50)min,P<0.001] and increased number of REM sleep[7.00(5.50,11.00)vs.5.00(4.00,6.00),P<0.001].The mean apnea hypopnea index was 3.30(1.10,11.05)n/h in25 patients with NT1,4 of whom(16%)had mild obstructive sleep apnea-hypopnea syndrome(OSAHS),2 of whom(8%)had moderate OSAHS and 2 of whom(8%)had severe OSAHS.5patients of NT1(20%)had an increased periodic limb movement index(more than 5 n/h)during sleep and 8 patients of NT1(32%)had rapid eye movement sleep without atonia(RSWA).Patients with NT1 had significantly shorter mean sleep latency than control group [1.50(1.15,4.50)min vs.14.45(11.96,16.00)min,P < 0.001].24 of 25 patients with NT1 had more than 2 SOREMPs,and the mean number of SOREMPs occurred 3(2,4)n.3.In overall,the sympathetic nerve index was significantly higher in patients with NT1 than controls(1.10±1.02 vs.0.35±0.93,P<0.05).In time domain,compared with control group,patients with NT1 had significantly shorter mean RR interval(719.68 ± 98.65 ms vs.806.65 ±91.99 ms,P < 0.05),increased mean heart rate(84.84 ± 11.57 bpm vs.75.35 ± 8.47 bpm,P <0.05),increased maximum heart rate(94.40 ± 12.83 bpm vs.88.35 ± 9.26 bpm,P < 0.05),and lower number of pairs of adjacent normal-to-normal intervals differing by more than 50 ms entire recording divided by the total number of all normal-to-normal intervals [p NN50,19.04(8.10,32.89)% vs.35.70(28.40,45.33)%,P < 0.05).In frequency domain,there were no significant differences in total power,very low frequency(VLF),low frequency(LF),high frequency(HF),normalized LF,normalized HF,and LF/HF between NT1 and controls(P > 0.05).In nonlinear analysis,compared with control group,patients with NT1 had significantly lower standard deviation along the line of identity(SD2)to standard deviation perpendicular the line of identity(SD1)ratio [1.18±0.24 vs.1.45±0.34,P < 0.05],and higher DFA α2 [0.40(0.31,0.50)vs.0.34(0.27,0.38),P < 0.05].There were no significant differences in plasma dopamine,norepinephrine,epinephrine,methoxynorepinephrine,and methoxynorepinephrine levels between NT1 and controls(P > 0.05).4.There was no significant correction between the concentration of hcrt-1 in cerebral fluid and SCOPA-AUT total score,SNS index,mean RR interval,mean heart rate,maximum heart rate,p NN50 or SD2/SD1(P>0.05)。Conclusions:1.Patients with NT1 had significantly higher ESS scores.Patients with NT1 had significantly higher SCOPA-AUT scores,most notably in the digestive system,urinary system,cardiovascular system and sexual function.2.Patients with NT1 had disturbed nocturnal sleep architecture,and are prone to have comorbidities of OSAHS,REM sleep behavior disorder,RSWA,and periodic limb movements of sleep.3.Autonomic dysfunction in patients with NT1 was manifested by increased sympathetic activity,decreased parasympathetic activity,and decreased heart rate variability.