[Elderly people, precariousness, social handicap and length of stay: pilot study at the Lariboisière-Fernand Widal Hospital Group in Paris]. / Personnes âgées, précarité, handicap social et durée de séjour: étude pilote au groupe hospitalier Lariboisière-Fernand Widal de Paris.

OBJECTIVES: To administer a social handicap questionnaire associated with French DRGs (PMSI) to determine the social handicaps of a population hospitalized in a public health establishment and to measure the cost implications for the establishment due to increased length of stay (DMS). METHOD: A prospective pilot study has been carried out in the Lariboisière-Fernand Widal Hospital Group in Paris targeting users 50 or more years old hospitalized for short stays in medicine, surgery and obstetrics. Data of the PMSI and answers to the questionnaire for hospitalisations longer than 24 hours have been exploited. RESULTS: Two hundred twenty-two stays from 8 to 23 November 2005 have been analyzed: 140 pertained to patients aged 50-69 years (27.8%) and 82 to patients aged 70 or more years (16.3%). Three-fourths of the persons aged 50-69 and 70 or over presented a social handicap: 45% showed a strong handicap and a third an average handicap. The three indicators "renter/owner", "interior comfort" and "family relations" were the major determinants of social handicap for those aged 70 or more, 50-69 and 50 or more years. For the patients 70 years and over and those 50-69 years, with an average handicap, the indicator was "income" with the domain "patrimony." For strong handicaps, it was the indicator "scolarisation" for the 70 or more years and the indicator "income" for the 50-69 years old. When all classes and populations were pooled, the DMS was significantly lower than that of the ENC (p<0.001 for the 70 years and over; p<0.05 for the 50-69 years). With again all classes and populations pooled, patients 70 and over stayed in hospital 6.50 days less on average compared to data published by the ENC; those 50-69 years stayed 3.57 days less. Persons aged 50 and over with a social handicap remained hospitalized on average more than 2.5 days: 2.2 days for the 70 and over and 3.1 days for the 50-69 years group. In terms of hospital days that produces an increase of 18%, corresponding to a supplementary expenditure attributable to social handicap of approximately 5.9 million euros. CONCLUSION: This pilot study with a questionnaire disability social PMSI proposing specific aid, but also reducing the DMS, provides several promising information but also indicates the limits of our approach. Among these, we note in particular: (a) its regular feasibility requires constant supervision, wider and well-trained, (b) that the measurement of our tool can only be affirmed after its use in many patients, and (c) the classification of disability in social class could even be discussed again. We still wanted to explore whether through this initiative without much logistical, markers of interest had emerged, which seems to be the case.

[Analysis of fourteen French national programmes on physical activity and sports as determinants of health from 2001 to 2006]. / Analyse de quatorze actions nationales pour le déterminant de santé activités physiques et sportives en France de 2001 à 2006.

Physical activity and sports are considered as one of the determinants of health. The aim of this study is to review the rationale for the formulation of this public health issue and its integration in national action plans. The study shows that fourteen national programmes were drafted and implemented between 2001 and 2006 by seven institutions. The research methodology was based on crossing data obtained from semi-directed interviews and documents regarding the design, implementation and follow-up of these programmes. For the conditions of the success, the fourteen actions scored an average of 175.0 +/- 66.9 out of 300%. Public health actors and professionals must be given more opportunities to involve themselves and engage in developing stronger relationships and linkages, in particular with the institutional and community settings. In general, the most invested parts of a programme are the structural and operational aspects of activities. Six significant points surfaced from the study: consideration of drug use as an addictive behaviour; recognition of the psychological stress of professional athletes; acknowledgment of youth as being at high risk for doping behaviour; integration of the concept that physical activity and sports must take the benefit/risk perspective into account; and the necessity to promote health. Through the exchange of numerous local and regional experiences, an optimisation of their synergistic connections was made possible on a continuum extending from "health promotion through physical activity and sports" to "prevention of drug-use and doping behaviours". Professionals have been able to develop actions in the above-mentioned domains across this continuum that have, to date, remained isolated. Proposals are made to strengthen these dynamics. Other health determinants and public health priorities could be investigated with the same methodology.

[What prevention programmes and which organizations are needed to support healthy ageing?]. / Quelles actions de prévention et quelles organisations pour un vieillissement réussi?

Physical activity and exercise are recognized as one of the determinants of health. This study aims to produce a review of the logical foundations at work that support the identification of a public health problem for this determinant and how to address it through national action. The research is based on cross-analysis of data from semi-directed interviews and data extracted from documents on the development, implementation and follow-up of such actions and programmes. The study shows that fourteen national programmes were created and implemented by seven different agencies. These fourteen activities scored an average of 175 +/- 66.9 out of 300%. Actors and professionals in the field must be given more capacity to be implicated and involved while simultaneously encouraging the strengthening of relationships with their environment, in particular the institutional and organizational settings as well as the community components. In general, the structural and operational aspects of action are those which receive the most investment in such activities. Six main points arose as important: doping considered as a addictive mechanism, acknowledgement of the psychological suffering of professional athletes, youth at high risk of doping, and that the concepts of physical activity and sports should take into account a risk/ benefit analysis and the necessity to first and foremost promote health. The act of sharing and exchanging a number of experiences, at the local and regional level, resulted in the identification of synergies between these experiences on a continuum from "health promotion through physical activity and sports" to "prevention of doping". Within this framework, professionals were able to develop activities in the aforementioned domains, which until now had remained isolated and marginal. Recommendations were made to reinforce and strengthen this dynamic. Other determinants of health and public health priorities could be explored using the same methodology.

Deciphering the metabolic and mechanical contributions to the exercise-induced circulatory response: insights from eccentric cycling.

Metabolic demand and muscle mechanical tension are closely coupled during exercise, making their respective drives to the circulatory response difficult to establish. This coupling being altered in eccentric cycling, we implemented an experimental design featuring eccentric vs. concentric constant-load cycling bouts to gain insights into the control of the exercise-induced circulatory response in humans. Heart rate (HR), stroke volume (SV), cardiac output (Q), oxygen uptake (V(.-)(O(2))), and electromyographic (EMG) activity of quadriceps muscles were measured in 11 subjects during heavy concentric (heavy CON: 270 +/- 13 W; V(.-)(O(2)) = 3.59 +/- 0.20 l/min), heavy eccentric (heavy ECC: 270 +/- 13 W, V(.-)(O(2)) = 1.17 +/- 0.15 l/min), and light concentric (light CON: 70 +/- 9 W, V(.-)(O(2)) = 1.14 +/- 0.12 l/min) cycle bouts. Using a reductionist approach, the circulatory responses observed between heavy CON vs. light CON (difference in V(.-)(O(2)) and power output) was ascribed either to metabolic demand, as estimated from heavy CON vs. heavy ECC (similar power output, different V(.-)(O(2))), or to muscle mechanical tension, as estimated from heavy ECC vs. light CON (similar V(.-)(O(2)), different power output). 74% of the Q response was determined by the metabolic demand, also accounting for 65% and 84% of HR and SV responses, respectively. Consequently, muscle mechanical tension determined 26%, 35%, and 16% of the Q, HR, and SV responses, respectively. Q was significantly related to V(.-)(O(2)) (r(2) = 0.83) and EMG activity (r(2) = 0.82; both P < 0.001). These results suggest that the exercise-induced circulatory response is mainly under metabolic control and support the idea that the level of muscle activation plays a role in the cardiovascular regulation during cycle exercise in humans.

Exercise training in normobaric hypoxia in endurance runners. I. Improvement in aerobic performance capacity.

This study investigates whether a 6-wk intermittent hypoxia training (IHT), designed to avoid reductions in training loads and intensities, improves the endurance performance capacity of competitive distance runners. Eighteen athletes were randomly assigned to train in normoxia [Nor group; n = 9; maximal oxygen uptake (VO2 max) = 61.5 +/- 1.1 ml x kg(-1) x min(-1)] or intermittently in hypoxia (Hyp group; n = 9; VO2 max = 64.2 +/- 1.2 ml x kg(-1) x min(-1)). Into their usual normoxic training schedule, athletes included two weekly high-intensity (second ventilatory threshold) and moderate-duration (24-40 min) training sessions, performed either in normoxia [inspired O2 fraction (FiO2) = 20.9%] or in normobaric hypoxia (FiO2) = 14.5%). Before and after training, all athletes realized 1) a normoxic and hypoxic incremental test to determine VO2 max and ventilatory thresholds (first and second ventilatory threshold), and 2) an all-out test at the pretraining minimal velocity eliciting VO2 max to determine their time to exhaustion (T(lim)) and the parameters of O2 uptake (VO2) kinetics. Only the Hyp group significantly improved VO2 max (+5% at both FiO2, P < 0.05), without changes in blood O2-carrying capacity. Moreover, T(lim) lengthened in the Hyp group only (+35%, P < 0.001), without significant modifications of VO2 kinetics. Despite similar training load, the Nor group displayed no such improvements, with unchanged VO2 max (+1%, nonsignificant), T(lim) (+10%, nonsignificant), and VO2 kinetics. In addition, T(lim) improvements in the Hyp group were not correlated with concomitant modifications of other parameters, including VO2 max or VO2 kinetics. The present IHT model, involving specific high-intensity and moderate-duration hypoxic sessions, may potentialize the metabolic stimuli of training in already trained athletes and elicit peripheral muscle adaptations, resulting in increased endurance performance capacity.

Ventilation efficiency and pulmonary function after a wheelchair interval-training program in subjects with recent spinal cord injury.

OBJECTIVE: To study the effect of a wheelchair interval-training program on the ventilatory function of subjects with recent spinal cord injury (SCI). DESIGN: Evaluation trial before and after a training program. SETTING: Center of reeducation and university hospital. PARTICIPANTS: Six subjects (5 men, 1 woman) hospitalized after a recent SCI. INTERVENTION: On a wheelchair ergometer, subjects with SCI performed 30 minutes of interval training 3 times a week for 6 weeks. The training program was part of their reeducation program. MAIN OUTCOME MEASURES: Spirometric values at rest and dynamic ventilatory responses were studied before and after this training program with a spirometric test, a maximal exercise test that increased by 5W every 2 minutes, and a submaximal test. RESULTS: Spirometric values at rest did not change after training. At maximal exercise, peak ventilation (Vepeak, 7.5%), peak breathing frequency (f peak) (-13.4%), peak tidal volume (Vtpeak +28.9%), and the ventilatory reserve (12.9%) improved after training. The oxygen cost of Ve decreased significantly (-20%) after training. We observed for the wheelchair tests that, at the same workload after training, Ve and f decreased and Vt increased. CONCLUSIONS: After 6 weeks of our interval-training program in subjects with recent SCI, the increase of Vt and the decrease of oxygen cost of Ve indicated better ventilatory efficiency.

Exercising with a denervated heart after cardiac transplantation.

Heart transplantation (HTR) is now an accepted life-extending procedure for those dying of intractable heart failure (CHF). HTR patients expect a high quality of life which implies a reasonable exercise capacity. Nevertheless HTR present unique exercise challenges with both central and peripheral factors of limitation that result in peak oxygen uptakes of 60-70% of age-matched normal subjects. Among central factors persistent chronotropic incompetence questions the occurrence and role of the graft reinnervation. Among peripheral factors the energetic impairement of the skeletal muscle seem to result more from microvascular abnormalities than from an actual deficit in oxidative capacity, questioning the mechanism of recovery from the CHF peripheral myopathy and the role of immunosuppressive drugs. Endurance and resistance training programs may reverse at least in part most but not all of these abnormalities. Training permits patients to engage in sports and even to participate in competitive events that are rewarding to them but also to the community because it promotes organ donation and confidence in medical achievements. Mechanisms of exercise impairments and improvements resulting from training are discussed in the perspective of current literature. Areas of future research and recommendations for the practice of sports after HTR are suggested.

Intermittent exercise test in chronic obstructive pulmonary disease patients: how do the pulmonary hemodynamics adapt?

PURPOSE: Endurance training is an important component of rehabilitation in patients with chronic obstructive pulmonary disease (COPD). In our study, we investigated the pulmonary hemodynamics' adaptation during a high-intensity intermittent exercise in such patients. METHODS: Eight patients underwent a 30-min exercise, alternating a 4-min work set at their first ventilatory threshold with a 1-min exercise set at 90% of their maximal tolerated power output. Pulmonary arterial pressure was measured by means of a right heart catheter. Cardiac output was calculated using the Fick's principle applied to oxygen. RESULTS: VO(2), cardiac output, and ventilation increased during the first minutes of exercise and remained stable thereafter. Heart rate increased significantly and progressively to its maximal value from rest to the end of the test (P < 0.001). After an initial increase, stroke volume decreased significantly (P < 0.05). Pulmonary arterial pressure increased from rest (mean +/- SEM 23.9 +/- 2.1 mm Hg) to the fifth minute of exercise (41.6 +/- 2.8 mm Hg), and decreased significantly thereafter (35.2 +/- 3.3 mm Hg at the 30th minute) (P < 0.001). Total pulmonary vascular resistance decreased from rest to the end of the test (P < 0.001). CONCLUSION: The high-intensity 1-min bouts of work of our intermittent work exercise are well tolerated without pushing the pulmonary arterial pressure dramatically high in COPD patients.

Cardiac output and oxygen release during very high-intensity exercise performed until exhaustion.

Our objectives were firstly, to study the patterns of the cardiac output (Q(.)) and the arteriovenous oxygen difference [(a-nu(-))O(2)] responses to oxygen uptake (V(.)O(2)) during constant workload exercise (CWE) performed above the respiratory compensation point (RCP), and secondly, to establish the relationships between their kinetics and the time to exhaustion. Nine subjects performed two tests: a maximal incremental exercise test (IET) to determine the maximal V(.)O(2) (V(.)O(2)peak), and a CWE test to exhaustion, performed at p Delta50 (intermediate power between RCP and V(.)O(2)peak). During CWE, V(.)O(2) was measured breath-by-breath, Q(.) was measured beat-by-beat with an impedance device, and blood lactate (LA) was sampled each minute. To calculate ( a-nu(-)O(2), the values of V(.)O(2) and Q(.) were synchronised over 10 s intervals. A fitting method was used to describe the V(.)O(2), Q(.) and ( a-nu(-))O(2) kinetics. The ( a-nu(-)O(2) difference followed a rapid monoexponential function, whereas both V(.)O(2) and Q(.) were best fitted by a single exponential plus linear increase: the time constant (tau) V(.)O(2) [57 (20 s)] was similar to tau ( a-nu(-)O(2), whereas tau for Q(.) was significantly higher [89 (34) s, P <0.05] (values expressed as the mean and standard error). LA started to increase after 2 min CWE then increased rapidly, reaching a similar maximal value as that seen during the IET. During CWE, the rapid component of V(.)O(2) uptake was determined by a rapid and maximal ( a-nu(-)O(2) extraction coupled with a two-fold longer Q(.) increase. It is likely that lactic acidosis markedly increased oxygen availability, which when associated with the slow linear increase of Q(.), may account for the V(.)O(2) slow component. Time to exhaustion was larger in individuals with shorter time delay for ( a-nu(-)O(2) and a greater tau for Q(.).

Pulmonary hemodynamics during a strenuous intermittent exercise in healthy subjects.

PURPOSE: It has been suggested that an intermittent work exercise test (IWET) is as efficient but better tolerated than continuous exercise for rehabilitation. Although systemic and pulmonary cardiovascular adjustments have been investigated for continuous exercise, it has not been done for IWET with exercise bouts near maximal work rate. METHODS: In seven healthy subjects, the pulmonary hemodynamics have been studied by the aid of heart catheterization during a strenuous 30-min bicycle IWET where a 4-min work set at the first ventilatory threshold (VT1) alternated with a 1-min work set at the second ventilatory threshold (VT2). RESULTS: During the IWET, cardiac output increased then remained stable with decreasing stroke volume and increasing heart rate, which became near maximal at the end of the test. Mean pulmonary arterial pressure increased from rest to the fifth minute of exercise and decreased significantly thereafter (P<0.01). An identical evolution was observed for mean systemic arterial pressure (SAP). CONCLUSION: Pulmonary hemodynamics adapt well in healthy subjects during a strenuous IWET despite the performance of exercise bouts of near maximal intensity.

Preserved response of mitochondrial function to short-term endurance training in skeletal muscle of heart transplant recipients.

OBJECTIVES: We sought to determine whether intrinsic mitochondrial function and regulation were altered in heart transplant recipients (HTRs) and to investigate the response of mitochondrial function to six-week endurance training in these patients. BACKGROUND: Despite the normalization of central oxygen transport during exercise, HTRs are still characterized by limited exercise capacity, which is thought to result from skeletal muscle metabolic abnormalities. METHODS: Twenty HTRS agreed to have vastus lateralis biopsies and exercise testing: before and after training for 12 of them and before and after the same control period for eight subjects unwilling to train. Mitochondrial respiration was evaluated on saponin-permeabilized muscle fibers in the absence or presence (maximum respiration rate [V(max)]) of saturating adenosine diphosphate. RESULTS: Mitochondrial function was preserved at the level of sedentary subjects in untrained HTRs, although they showed 28 +/- 5% functional aerobic impairment (FAI). After training, V(max), citrate synthase, cytochrome c oxidase, and mitochondrial creatine kinase (CK) activities were significantly increased by 48%, 40%, 67%, and 53%, respectively (p < 0.05), whereas FAI decreased to 12 +/- 5% (p < 0.01). The control of mitochondrial respiration by creatine and mitochondrial CK was also improved (p < 0.01), suggesting that phosphocreatine synthesis and transfer by the mitochondrial CK become coupled to oxidative phosphorylation, as shown in trained, healthy subjects. CONCLUSIONS: In HTRs, the mitochondrial properties of skeletal muscle were preserved and responded well to training, reaching values of physically active, healthy subjects. This suggests that, in HTRs, immunosuppressive drugs do not alter the intrinsic muscle oxidative capacities and that the patients' physical handicap results from nonmitochondrial mechanisms.

Mitochondrial respiratory chain function in skeletal muscle of ALS patients.

Evidence implicating mitochondrial dysfunction in the central nervous system of patients with sporadic amyotrophic lateral sclerosis (SALS) has recently been accumulating. In contrast, data on mitochondrial function in skeletal muscle in SALS are scarce and controversial. We investigated the in situ properties of muscle mitochondria in patients with early-stage SALS and sedentary (SED) controls using the skinned fiber technique to determine whether respiration of muscle tissue is altered in early-stage SALS in comparison with SED. Musculus vastus lateralis biopsies were obtained from 7 SED group members and 14 patients with early-stage SALS (mean disease duration, 9 months). Muscle fibers were permeabilized with saponine and then skinned and placed in an oxygraphic chamber to measure basal (V(0)) and maximal (V(max)) adenosine diphosphate-stimulated respiration rates and to assess mitochondrial regulation by adenosine diphosphate. Muscle oxidative capacity, evaluated with V(max), was identical in patients in the SALS and SED groups (V(0): SALS, 1.1 +/- 0.1; SED, 0.8 +/- 0.1, micromol 0(2). min(-1). gm(-1)dw and V(max): SALS, 3.1 +/- 0.3; SED, 2.5 +/- 0.3, micromol 0(2). min(-1). gm(-1)dw). This study shows an absence of large mitochondrial damage in skeletal muscle of patients with early-stage SALS, suggesting that mitochondrial dysfunction in the earlier stages of SALS is almost certainly not systemic.