Kinematic and Kinetic Patterns Related to Free-Walking in Parkinson's Disease.

The aim of this study is to compare the properties of free-walking at a natural pace between mild Parkinson's disease (PD) patients during the ON-clinical status and two control groups. In-shoe pressure-sensitive insoles were used to quantify the temporal and force characteristics of a 5-min free-walking in 11 PD patients, in 16 young healthy controls, and in 12 age-matched healthy controls. Inferential statistics analyses were performed on the kinematic and kinetic parameters to compare groups' performances, whereas feature selection analyses and automatic classification were used to identify the signature of parkinsonian gait and to assess the performance of group classification, respectively. Compared to healthy subjects, the PD patients' gait pattern presented significant differences in kinematic parameters associated with bilateral coordination but not in kinetics. Specifically, patients showed an increased variability in double support time, greater gait asymmetry and phase deviation, and also poorer phase coordination. Feature selection analyses based on the ReliefF algorithm on the differential parameters in PD patients revealed an effect of the clinical status, especially true in double support time variability and gait asymmetry. Automatic classification of PD patients, young and senior subjects confirmed that kinematic predictors produced a slightly better classification performance than kinetic predictors. Overall, classification accuracy of groups with a linear discriminant model which included the whole set of features (i.e., demographics and parameters extracted from the sensors) was 64.1%.

Physical activity, body functions and disability among middle-aged and older Spanish adults.

BACKGROUND: Physical activity (PA) is a health determinant among middle-aged and older adults. In contrast, poor health is expected to have a negative impact on PA. This study sought to assess to what extent specific International Classification of Functioning, Disability and Health (ICF) health components were associated with PA among older adults. METHODS: We used a sample of 864 persons aged ≥50 years, positively screened for disability or cognition in a cross-sectional community survey in Spain. Weekly energy expenditure during PA was measured with the Yale Physical Activity Survey (YPAS) scale. The associations between body function impairment, health conditions or World Health Organization Disability Assessment Schedule (WHODAS 2.0) disability scores and energy expenditure were quantified using negative-binomial regression, and expressed in terms of adjusted mean ratios (aMRs). RESULTS: Mean energy expenditure was 4542 Kcal/week. A lower weekly energy expenditure was associated with: severe/extreme impairment of mental functions, aMR 0.38, 95% confidence interval, CI (0.21-0.68), and neuromusculoskeletal and movement functions, aMR 0.50 (0.35-0.72); WHODAS 2.0 disability, aMR 0.55 (0.34-0.91); dementia, aMR 0.45 (0.31-0.66); and heart failure, aMR 0.54 (0.34-0.87). In contrast, people with arthritis/osteoarthritis had a higher energy expenditure, aMR 1.27 (1.07-1.51). CONCLUSION: Our results suggest that there is a strong relationship between selected body function impairments, mainly mental, and PA. Although more research is needed to fully understand causal relationships, strategies to improve PA among the elderly may require targeting mental, neuromusculoskeletal and movement functions, disability determinants (including barriers), and specific approaches for persons with dementia or heart failure.

Associations between chronic conditions, body functions, activity limitations and participation restrictions: a cross-sectional approach in Spanish non-clinical populations.

OBJECTIVES: To analyse the relationships between chronic conditions, body functions, activity limitations and participation restrictions in the International Classification of Functioning, Disability and Health (ICF) framework. DESIGN: A cross-sectional study. SETTING: 2 geographical areas in the Autonomous Region of Aragon, Spain, namely, a rural area, Cinco Villas, and an urban area in the city of Zaragoza. PARTICIPANTS: 864 individuals selected by simple random sampling from the register of Social Security card holders, aged 50 years and over, positive to disability screening. MAIN OUTCOME MEASURES: ICF Checklist-body function domains, WHO Disability Assessment Schedule 2.0 (WHODAS 2.0, 36-item (WHODAS-36)) global scores and medical diagnoses (chronic conditions) from primary care records. RESULTS: Mild disability (WHODAS-36 level 5-24%) was present in 51.5% of the sample. In the adjusted ordinal regression model with WHODAS-36 as the dependent variable, disability was substantially associated with moderate-to-complete impairment in the following functions: mental, OR 212.8 (95% CI 72 to 628.9); neuromusculoskeletal, OR 44.8 (24.2 to 82.8); and sensory and pain, OR 6.3 (3.5 to 11.2). In the relationship between health conditions and body function impairments, the strongest links were seen for: dementia with mental functions, OR 50.6 (25.1 to 102.1); cerebrovascular disease with neuromusculoskeletal function, OR 5.8 (3.5 to 9.7); and chronic renal failure with sensory function and pain, OR 3.0 (1.49 to 6.4). Dementia, OR 8.1 (4.4 to 14.7) and cerebrovascular disease, OR 4.1 (2.7 to 6.4) were associated with WHODAS-36 scores. CONCLUSIONS: Body functions are heterogeneously linked to limitations in activities and restrictions on participation, with the highest impact being due to mental and musculoskeletal functions. This may be relevant for disability assessment and intervention design, particularly if defined on a body function basis. Control of specific health conditions, such as dementia and cerebrovascular disease, appears to be paramount in reducing disability among persons aged 50 years and over.

Serum lipid profile in subjects with traumatic spinal cord injury.

BACKGROUND AND AIMS: Few large studies have examined the relationship between spinal cord injury (SCI) and lipid profile. We studied serum lipid concentrations in subjects with traumatic SCI in relation to the degree of neurological involvement and time since injury, and compared them with values from a reference sample for the Spanish population (DRECE study). MATERIALS AND METHODS: A retrospective cohort was built from 177 consecutive cases with traumatic SCI admitted to the SCI unit of the Miguel Servet Hospital in Aragon (Spain). Outcome measures (cholesterol, triglycerides, HDL-c and LDL-c levels) were analyzed according to the ASIA Impairment Scale (AIS), neurological level of injury (involvement of all limbs vs. only lower limbs), and time since injury. All analyses were adjusted for age and sex. RESULTS: Cases without preserved motor function (AIS A or B) had lower total and HDL cholesterol than the others (-11.4 [-21.5, -1.4] mg/dL total cholesterol and -5.1 [-8.8, -1.4] mg/dL HDL-c), and cases with all-limb involvement had lower total, HDL, and LDL cholesterol than those with only lower-limb involvement (-14.0 [-24.6, -3.4] mg/dL total cholesterol, -4.1 [-8.0, -0.2] mg/dL HDL-c, and -10.0 [-19.7, -0.3] mg/dL LDL-c) (all p<0.05). No association was found between lipid concentrations and time since injury. Concentrations of lipid subfractions and triglycerides in SCI subjects were lower than in sex- and age-stratified values from the reference sample. CONCLUSION: A high degree of neurological involvement in SCI (anatomically higher lesions and AIS A or B) is associated with lower total cholesterol and HDL-c.

Incidence of traumatic spinal cord injury in Aragón, Spain (1972-2008).

Long-term incidence studies are required to identify high-risk groups, establish trends, and forecast needs, and thus contribute to health care planning in spinal cord injury (SCI). This study aimed to determine the incidence of traumatic SCI over a 36-year period in Aragón, Spain, and compare rates with other published European estimates. Hospital records from the Servet Hospital, the only specialized SCI unit in the region, of a retrospective cohort with traumatic SCI between January 1972 and December 2008 were reviewed. Specification of SCI patient demographics, injury causes, and related factors was achieved by utilizing medical records available for inpatients, hospital archives, and central databases. A total of 540 cases were reported over the 36-year study period (79% were male). The age- and sex-adjusted incidence rate was 15.5 per million population (18.8 for males and 4.9 for females). Two incidence peaks were suggested, in the 20- to 29-year and 60- to 69-year age groups. Traffic accidents and falls were the main causes of injury. The highest peak occurs in young adults, mainly caused by traffic accidents. The majority of the lesions were at cervical or thoracic level, and ASIA grade A was most frequently observed. The proportion of SCI cases in persons older than 60 years, mostly due to falls, is increasing. The age-adjusted incidence rates found for the region of Aragón in Spain fall within the range of other published European estimates. Comparative epidemiological features for 2001-2008 suggest that there is room for prevention.

ICF-based disability survey in a rural population of adults and older adults living in Cinco Villas, Northeastern Spain: design, methods and population characteristics.

BACKGROUND: This article describes the methods of a door-to-door screening survey exploring the distribution of disability and its major determinants in northeastern Spain. This study will set the basis for the development of disability-related services for the rural elderly in northeastern Spain. METHODS: The probabilistic sample was composed of 1,354 de facto residents from a population of 12,784 Social Security card holders (age: > or = 50 years). Cognitive and disability screenings were conducted (period: June 2008-June 2009). Screening instruments were the MMSE and the World Health Organization Disability Assessment Schedule. Participants screened positive for disability underwent an assessment protocol focusing on primary care diagnoses, disability, lifestyle, and social and health service usage. Participants screened positive for cognitive functioning went through in-depth neurological evaluation. RESULTS: The study sample is described. Usable data were available for 1,216 participants. A total of 625 individuals (51.4%) scored within the positive range in the disability screening, while 135 (11.1%) scored within the positive range of the cognitive screening. The proportion of positively screened individuals was higher for women and increased with age. CONCLUSIONS: Screening surveys represent a feasible design for examining the distribution of disability and its determinants among the elderly. Data quality may benefit from methodological developments tailored to rural populations with a low education level.

Startle-induced reaction time shortening is not modified by prepulse inhibition.

A startling auditory stimulus delivered during preparation for execution of a ballistic movement in a simple reaction time task experiment induces two effects: a startle response and a reaction time shortening (the StartReact effect). We investigated whether prepulse inhibition of the startle response is effective in suppressing either one of these effects during motor preparation. Twelve healthy volunteers were presented with seven different experimental conditions in random order: while at rest, subjects received a low intensity electrical shock on the middle finger of the left hand (Prep), a loud auditory stimulus (Start), or a combination of these two (PrepStart). While engaged in preparation for a visual simple reaction time task, they were presented with the imperative signal for execution of the reaction (React), or with any of the combinations PrepReact, StartReact, or PrepStartReact. We recorded the EMG activity from the orbicularis oculi and the sternocleidomastoid muscles to assess the startle response, and from the wrist extensor muscles to assess reaction time. The startle response was markedly reduced when Prep was presented 100 ms before Start regardless of whether the subjects were at rest or preparing for the reaction. Reaction time shortened significantly in StartReact trials with respect to React trials, and the percentage shortening was not different in trials in which Prep preceded StartReact and inhibited the startle response. The fact that prepulse inhibition of the startle response is not accompanied by modification of the StartReact effect indicates that there are separate physiological mechanisms for the two effects, an observation that has implications for further understanding of the processes underlying motor preparation for a ballistic reaction.