Postural control abnormalities related to sleep deprivation in patients with Marfan Syndrome.

BACKGROUND: Marfan syndrome (MFS) is a rare autosomal dominant connective tissue disorder affecting virtually every organ. Sleep disturbances, associated to high collapsibility in upper airways, are common in MFS; daytime sleepiness could lead to reduction in attention and motor coordination, with detrimental effects on balance. OBJECTIVE: To evaluate otoneurological function in MFS patients, compared to healthy subjects, and to investigate possible correlations with sleep deprivation extent. METHODS: Forty-one MFS patients underwent a thorough otoneurological examination, video Head Impulse Test (vHIT), and static posturography. Sleep parameters were recorded by home monitoring. Daytime sleepiness and dizziness-related handicap were screened by means of Dizziness Handicap Inventory (DHI) and Epworth Sleepiness Scale (ESS). Results were compared with 49 healthy controls (HC). RESULTS: DHI and ESS scores were increased in MFS patients (p < 0,01). vHIT scores showed no between-group effect. Classical (surface and length) and frequency-domain posturographic parameters were significantly increased in MFS with respect to HC (p < 0,01). A positive correlation was found between ESS scores and posturographic parameters in MFS patients. CONCLUSIONS: An impaired postural control, related to the extent of sleep deprivation, was found in MFS patients. Such results could advocate for screening and treating sleep deprivation and balance dysfunctions in MFS patients.

Visual dependency and postural control on swing performance in golf players.

Individuals have to reweight the respective contribution of the different sources of sensorial information for regulating posture and balance, especially during fine task execution. Given the evidences indicating strategy during swing performance as associated with prioritization of task-relevant visuospatial information for skill execution, the aim of the present work is to assess differences in visual dependency (VD) and postural control in a population of expert (EXP) and non-expert (NEXP) golfers when compared with healthy subjects (HC) and to discover possible relationships between these outcomes and swing performance. Thus, 15 golfers (EXP = 7; NEXP = 8) and 32 matched HC underwent otoneurological testing including video Head Impulse Test, posturography and Rod and Disk Test (RDT). Golf players also underwent a swing session procedure, which performance was measured by means of the Flightscope X2 Doppler-radar launch monitor system. EXP subjects demonstrated significant (p < 0.05) lower values in i) counter-clockwise (CCW) and clockwise (CW) dynamic conditions when compared with both NEXP and HC subjects RDT outcome measures and ii) surface and length posturography values as compared with HC subjects. When treating golf players outcomes as 'a continuum', CCW and CW scores were found to positively correlate with both lateral distance and horizontal launch angle and to negatively correlate with spin rpm. In conclusion, the present study suggests that the high-level of visual-independency demonstrated by EXP subjects may be functionally related in expert golfers to an effective motor strategy preferentially not referring to an inappropriate reliance on visual input.

Postural and vestibular changes related to CPAP treatment in moderate-to-severe OSA patients: a 12-month longitudinal study.

PURPOSE: To assess whether vestibulo-ocular reflex (VOR) gain, posturography parameters and related clinical outcomes can improve in OSA patients after 12 months of CPAP treatment, taking into consideration that a certain degree of vestibular dysfunction has been identified in these subjects. METHODS: Vestibular, postural, clinical, and polygraphic parameters were assessed in 32 OSA patients before and after beneficial CPAP treatment by means of video head impulse test (vHIT), static posturography (SP), Dizziness Handicap Inventory (DHI), Epworth Sleepiness Scale (ESS), and Apnea-Hypopnea Index (AHI), respectively, and were compared by means of a "within-subject" ANOVA model and Spearman's rank correlation. RESULTS: After the 12-month period of treatment, OSA patients demonstrated a significant reduction in AHI values, in both opened and closed eyes conditions of surface and length as well as in power spectra recorded in low, middle, and high frequency interval. Although a significant improvement was also recorded among DHI and ESS scores, VOR gain increase did not survive to post-hoc corrections. Finally, positive correlations between the differences between pre- and post-treatment AHI, ESS, and PS values were found. CONCLUSIONS: The present work highlighted that postural instability and dizziness-related conditions due to OSA may improve after 12 months of CPAP treatment. Although VOR gain did not demonstrate significant improvement, this study might open future perspectives directed to assessing VOR gain changes after longer periods of CPAP treatment.