| Aims We aimed to investigate the systemic symptoms of patients with neuromyelitis optica spectrum disorders(NMOSD). We surveyed fatigue, sleep disorders and cognitive dysfunction. We attempted to identify factors that may impact on these systemic symptoms. The goal of this investigation is to expand our recognition of these systemic symptoms, deepen understanding of the pathophysiological mechanisms of NMO, and to provide a theoretical basis for improving management in NMOSD patients.Subjects and MethodsThirty-three NMOSD patients and twenty healthy controls matched with age, sex and years of education were consecutively enrolled from Tianjin Medical University General Hospital during the time from September 2013 to June 2014.Clinical data collected in this study included demographic information,NMOSD-related medical history and MRI in brain and spinal cord. A series of subjective questionnaires were administered by a psychological specialist. Sleep quality was measured by using the Pittsburgh Sleep Quality Index(PSQI). Sleepiness was measured by the Epworth Sleepiness Scale(ESS). The Fatigue Questionnaire(FQ) was used to measure physical and mental fatigue. Depression was measured by the Beck Depression Inventory(BDI-II). The capacity to perform daily activities was assessed using modified 20-item Activities of Daily Living Scale(ADL) and the Minimal Assessment of Cognitive Function in Multiple Sclerosis(MACFIMS) were assessed for cognition. Overnight video PSG examinations were performed for all participants using the sleep laboratory digital system(Nicolet v32, USA).SPSS17.0 statistical software package was used for statistical analysis. Taking test level α = 0.05, P < 0.05 was considered statistically significant.Results1. Fatigue(1) The prevalence of fatigueThe prevalence and level of fatigue were significantly higher in NMOSD than healthycontrols(prevalence: 64% vs 35%, P = 0.043; total fatigue score: 6.4 ± 0.6 vs 3.8 ±0.4, P = 0.001). Not only physical fatigue score but also mental fatigue score were both obviously higher compared with healthy controls respectively(physical fatigue:4.4 ± 0.4 vs 2.8 ± 0.3, P = 0.002; mental fatigue, 2.0 ± 0.3 vs 1.1 ± 0.2, P = 0.007).According FQ scale score, the patients were divided into two groups: fatigue group(FQ ≥ 4, n = 21) and non-fatigue group(FQ < 4, n = 12). With fatigue occurrence,ADL score in patients with fatigue were significantly higher than no fatigue(31.9 ±2.0 vs 23.7 ± 1.6, P = 0.003) and ADL showed a correlation with fatigue score(r =0.455, P = 0.008).(2) The influence factors for fatigue occurrence in patients with NMOSD Clinical data(e.g. AQP4 antibody status, disability level and disease duration) was similar between the two groups. BDI scale score in the fatigue group was significantly higher than the non-fatigue group(16.6 ± 2.5 vs 7.3 ± 2.1, P =0.016). In the fatigue group, the mean and nadir oxygen concentration(mean Sp O2,nadir Sp O2) in NMOSD patients were lower than the non-fatigue group(mean Sp O2:90% vs 94%, P = 0.004; nadir Sp O2: 87% vs 93 %, P = 0.002). Compared with the non-fatigue group, the quality of subjective sleep in the fatigue group was significant poorer(PSQI: 9.2 ± 1.2 vs 5.8 ± 1.0, P = 0.044; ESS: 7.3 ± 1.3 vs 3.8 ± 0.7,P = 0.024). The proportion of N3 period in non-rapid eye movement sleep in the fatigue group and non-fatigue group was(6.7 ± 1.0)% and(11.6 ± 2.3)%, the difference was statistically significant(P = 0.033). The number of sleep stage shifts in the two groups were 131.3 ± 9.3 and 103.5 ± 7.5, the difference was statistically significant(P = 0.049). Spearman correlation analysis showed that the degree of fatigue and depression was significantly correlated(r = 0.599, P < 0.001). The degree of fatigue and oxygen concentration were significant negatively correlated(mean Sp O2: r =-0.457, P = 0.007; nadir Sp O2: r =-0.558, P = 0.001). The degree of fatigue and PSQI score was positively correlated(r = 0.453, P = 0.008).2. Sleep abnormality in NMOSDThe objective indicators of sleep in PSG of NMOSD patients:(1) Sleep efficiency: Compared with the control group, SE in the NMOSD group was decreased(79% vs 86%, P = 0.034). Wake time after sleep onset(WASO) wasincreased 44 minutes(78 min vs 34 min, P < 0.0001).(2) Sleep architecture: Compared with the control group, rapid eye movement(REM)and non-REM period of N1(NREM-N1) in the NMOSD group were increased 4%and 6% respectively(16% vs 12%, P = 0.042; 16% vs 10% P = 0.001). The non-rapid eye movement stage N3(NREM-N3) in the NMOSD group was reduced 12%(8% vs20%,(P < 0.0001). Arousal index(AI) in the NMOSD group was lower than the control group(6 vs 12, P = 0.014).(3) Sleep disordered breathing: The proportion of sleep-disordered breathing in the NMOSD group was higher than the control group(18% vs 5%, P = 0.007). The mean Sp O2, nadir Sp O2 in the NMOSD group were lower than the control group(mean Sp O2: 94% vs 96%, P = 0.011; nadir Sp O2: 89% vs 92%, P = 0.039).(4) Periodic limb movement: Regarding periodic leg movement, the number of periodic limb movements per hour(PLMs / h) for NMOSD patients was higher than those of healthy controls(20 vs 2, P = 0.020). Patients with infratentorial lesions also had more PLMs / h than those without such lesions(41 vs 3, P = 0.001).3. Cognitive function(1) MMSE and Mo CA scores were significantly lower in NMOSD patients than those of healthy controls. NMOSD patients had significant impairment in the following cognitive tests: the PASAT(P < 0.05), the SDMT(P < 0.001), the total learning score of 5 trials, short-delay cued recall(SDCR), long-delay free recall(LDFR), long-delay cued recall(LDCR), the recognition of the BVMT-R(P < 0.05),and the semantic fluency(P < 0.001). The most common cognitive impairment occurred in memory.(2) NMOSD patients with cognitive impairment had elder age and lower education level than those with preserved cognition(P < 0.05)(age: 54.5 ± 1.9 vs 42.5 ± 3.0, P= 0.002; education: 8.4 ± 1.1 vs 11.2 ± 0.7, P = 0.028).Conclusions1. Compared with the healthy controls, the incidence of fatigue was significantly higher in patients with NMOSD, both physical fatigue and mental fatigue were present. Particularly, we found fatigue was significantly associated with a reduced activity of daily life and lowered the quality of life in NMOSD. Hypoxemia, sleepdisturbances and depression probably predicted fatigue in patients with NMOSD.2. Compared with the healthy controls, SE decreased, WASO increased, the proportion of REM and NREM-N1 increased, the proportion of NREM-N3 decreased,sleep disordered breathing was prominent, Sp O2 decreased, PLM was obvious in NMOSD patients.3. NMOSD patients had cognitive impairment, particularly in short-term and long-term memory function, visual and auditory information processing speed and so on. Elder age and lower education level were associated with cognitive impairment in NMOSD. |
PDF Full Text Request