Poor sleep quality is associated with cognitive, mobility, and anxiety disability that underlie freezing of gait in Parkinson's disease.

BACKGROUND: Individuals with Parkinson's disease (PD) who report freezing of gait (FOG) have poorer sleep quality than those without FOG. Cognitive, anxiety, and mobility disability are components of the FOG phenotype, however, no study has investigated if poor sleep quality is associated with all three components that underlie FOG in PD. RESEARCH QUESTION: Are there associations among sleep quality and all three components of the FOG phenotype? METHODS: Forty and 39 individuals with and without FOG (PD + FOG and PD-FOG), respectively, and 31 age-matched healthy controls (HC) participated in this study. Self-reported FOG (new-FOG questionnaire-NFOGQ), sleep quality (Pittsburgh Sleep Quality Index-PSQI), cognitive function (Montreal Cognitive Assessment-MoCA), anxiety (subscale from Hospital Anxiety and Depression Scale-HADS-A), and mobility (timed-up-and-go test-TUG) were assessed. RESULTS AND SIGNIFICANCE: PSQI scores were correlated with the scores of NFOGQ, MoCA, HADS-A, and TUG time in PD + FOG (P ≤ 0.0038). The multiple regression analysis identified the PSQI scores as the only predictor of the variance of the NFOGQ scores (R2 = 0.46, P < .0001). The variance in the PSQI scores were explained (69 %) by MoCA scores, NFOGQ scores, TUG time, and HADS-A scores (P ≤ 0.05). Although PD + FOG had a higher disease severity compared to PD-FOG (P < 0.001), disease severity did not enter in the regression model to explain PSQI scores and NFOGQ scores. We also observed associations of PSQI scores with the MoCA scores and TUG time for HC (P ≤ 0.0038), whereas there was no association between PSQI scores and any variable in PD-FOG (P > 0.05). Finally, PD + FOG presented worse scores of PSQI, MoCA, HADS-A, and TUG time than PD-FOG and HC (P < 0.05). Thus, poor sleep quality is associated with FOG and all three components that underlie FOG, regardless of the disease severity. Therefore, treatments useful to decrease FOG should be targeted to ameliorate sleep quality, cognition, anxiety, and mobility.

Hyponatremia and bone disease.

Hip fractures represent a serious health risk in the elderly, causing substantial morbidity and mortality. There is now a considerable volume of literature suggesting that chronic hyponatremia increases the adjusted odds ratio (OR) for both falls and fractures in the elderly. Hyponatremia appears to contribute to falls and fractures by two mechanisms. First, it produces mild cognitive impairment, resulting in unsteady gait and falls; this is probably due to the loss of glutamate (a neurotransmitter involved in gait function) as an osmolyte during brain adaptation to chronic hyponatremia. Second, hyponatremia directly contributes to osteoporosis and increased bone fragility by inducing increased bone resorption to mobilize sodium stores in bone. Low extracellular sodium directly stimulates osteoclastogenesis and bone resorptive activity through decreased cellular uptake of ascorbic acid and the induction of oxidative stress; these effects occur in a sodium level-dependent manner. Hyponatremic patients have elevated circulating arginine-vasopressin (AVP) levels, and AVP acting on two receptors expressed in osteoblasts and osteoclasts, Avpr1α and Avpr2, can increase bone resorption and decrease osteoblastogenesis. Should we be screening for low serum sodium in patients with osteoporosis or assessing bone mineral density (BMD) in patients with hyponatremia? The answers to these questions have not been established. Definitive answers will require randomized controlled studies that allocate elderly individuals with mild hyponatremia to receive either active treatment or no treatment for hyponatremia, to determine whether correction of hyponatremia prevents gait disturbances and changes in BMD, thereby reducing the risk of fractures. Until such studies are conducted, physicians caring for elderly patients must be aware of the association between hyponatremia and bone disorders. As serum sodium is a readily available, simple, and affordable biochemical measurement, clinicians should look for hyponatremia in elderly patients, especially in those receiving medications that can cause hyponatremia. Furthermore, elderly patients with an unsteady gait and/or confusion should be evaluated for the presence of mild hyponatremia, and if present, treatment should be initiated. Finally, elderly patients presenting with an orthopedic injury should have serum sodium checked and hyponatremia corrected, if present.

Spinal cord stimulation improves gait in patients with Parkinson's disease previously treated with deep brain stimulation.

BACKGROUND: Deep brain stimulation and levodopatherapy ameliorate motor manifestations in Parkinson's disease, but their effects on axial signs are not sustained in the long term. OBJECTIVES: The objective of this study was to investigate the safety and efficacy of spinal cord stimulation on gait disturbance in advanced Parkinson's disease. METHODS: A total of 4 Parkinson's disease patients who experienced significant postural instability and gait disturbance years after chronic subthalamic stimulation were treated with spinal cord stimulation at 300 Hz. Timed-Up-GO and 20-meter-walk tests, UPDRS III, freezing of gait questionnaire, and quality-of-life scores were measured at 6 months and compared to baseline values. Blinded assessments to measure performance in the Timed-Up-GO and 20-meter-walk tests were carried out during sham stimulation at 300 Hz and 60 Hz. RESULTS: Patients treated with spinal cord stimulation had approximately 50% to 65% improvement in gait measurements and 35% to 45% in UPDRS III and quality-of-life scores. During blinded evaluations, significant improvements in the Timed-Up-GO and 20-meter-walk tests were only recorded at 300 Hz. CONCLUSION: Spinal cord stimulation at 300 Hz was well tolerated and led to a significant improvement in gait. © 2016 International Parkinson and Movement Disorder Society.

Evaluation of normal and pathological gait of mice / Avaliação da marcha normal e patológica no camundongo

Gait analysis represents an important semiotic tool for the characterization of orthopedic, neuromuscular and neurological disorders in clinical practice. The pathological gait is the common final pathway of manifestations of neurological diseases (parkinsonian syndromes, cerebellar and sensory ataxia, spastic paraparesis and neuromuscular disease), rheumatologic disorders (arthritis in cases of collagen-related disorders and vasculitis) and orthopedic disturbances (joint and ligament degenerative lesions), allowing the understanding of its modified elements the proper comprehension of pathogenesis and topography of neuro-orthopedic injuries. This review article aims to summarize the main evaluation methods for the characterization of gait in experimental animal models.(AU)

A análise da marcha representa importante ferramenta semiológica para a caracterização de alterações ortopédicas, neuromusculares e neurológicas na prática médica. A marcha patológica representa via final comum de manifestações de doenças neurológicas (síndromes parkinsonianas, ataxias cerebelares e sensitivas, paraparesias espásticas e doenças neuromusculares), reumatológicas (artrites nas colagenoses e vasculites) e ortopédicas (lesões degenerativas articulares e ligamentares), podendo a compreensão de seus elementos modificados fornecer dados fundamentais para o entendimento da fisiopatogenia e da topografia de lesões neuro-ortopédicas. Este artigo de revisão objetiva resumir os principais métodos de avaliação para a caracterização da marcha em modelos experimentais animais.(AU)

Evaluation of normal and pathological gait of mice / Avaliação da marcha normal e patológica no camundongo

Gait analysis represents an important semiotic tool for the characterization of orthopedic, neuromuscular and neurological disorders in clinical practice. The pathological gait is the common final pathway of manifestations of neurological diseases (parkinsonian syndromes, cerebellar and sensory ataxia, spastic paraparesis and neuromuscular disease), rheumatologic disorders (arthritis in cases of collagen-related disorders and vasculitis) and orthopedic disturbances (joint and ligament degenerative lesions), allowing the understanding of its modified elements the proper comprehension of pathogenesis and topography of neuro-orthopedic injuries. This review article aims to summarize the main evaluation methods for the characterization of gait in experimental animal models.

A análise da marcha representa importante ferramenta semiológica para a caracterização de alterações ortopédicas, neuromusculares e neurológicas na prática médica. A marcha patológica representa via final comum de manifestações de doenças neurológicas (síndromes parkinsonianas, ataxias cerebelares e sensitivas, paraparesias espásticas e doenças neuromusculares), reumatológicas (artrites nas colagenoses e vasculites) e ortopédicas (lesões degenerativas articulares e ligamentares), podendo a compreensão de seus elementos modificados fornecer dados fundamentais para o entendimento da fisiopatogenia e da topografia de lesões neuro-ortopédicas. Este artigo de revisão objetiva resumir os principais métodos de avaliação para a caracterização da marcha em modelos experimentais animais.