Defining pathways to healthy sustainable urban development

Goals and pathways to achieve sustainable urban development have multiple interlinkages with human health and wellbeing. However, these interlinkages have not been examined in depth in recent discussions on urban sustainability and global urban science. This paper fills that gap by elaborating in detail the multiple links between urban sustainability and human health and by mapping research gaps at the interface of health and urban sustainability sciences. As researchers from a broad range of disciplines, we aimed to: 1) define the process of urbanization, highlighting distinctions from related concepts to support improved conceptual rigour in health research; 2) review the evidence linking health with urbanization, urbanicity, and cities and identify cross-cutting issues; and 3) highlight new research approaches needed to study complex urban systems and their links with health. This novel, comprehensive knowledge synthesis addresses issue of interest across multiple disciplines. Our review of concepts of urban development should be of particular value to researchers and practitioners in the health sciences, while our review of the links between urban environments and health should be of particular interest to those outside of public health. We identify specific actions to promote health through sustainable urban development that leaves no one behind, including: integrated planning; evidence-informed policy-making; and monitoring the implementation of policies. We also highlight the critical role of effective governance and equity-driven planning in progress towards sustainable, healthy, and just urban development

Upper airway imaging in sleep apnoea syndrome: clinical applications.

Symptoms of habitual snoring and excessive daytime sleepiness are extremely common in the general population, and have poor predictive value in identifying patients with "true" sleep-related disordered breathing. The upper airways are the main anatomical site responsible for snoring and sleep apnoea; therefore, their examination via different means has been quite extensively assessed. Clinical examination may point to severe micrognathia or retrognathia, grossly hypertrophied tonsils, obvious macroglossia, and oedema and inflammation of the uvula and soft palate. A recently proposed model is promising, but has not been validated independently yet. Endoscopic investigations have been performed in awake as well as in sleeping patients, with the pharynx in relaxed or active states; their predictive value remains poor, both for diagnostic purposes and for identifying patients that may benefit from surgery. Radiographic and magnetic resonance imaging techniques have permitted a detailed understanding of the process of narrowing and collapse of the upper airways. Unfortunately, these techniques do not perform any better than the ones previously cited as clinically efficient tools for diagnosis in the population of patients suspected of sleep-related breathing disorders. In conclusion, clinical examination of the upper airways remains part of the clinical evaluation of patients suspected of sleep-related disordered breathing. Other imaging techniques may be used for research purposes, but do not yet seem to be worth including in the routine assessment of this population

Failure of Body Plethysmography in Bronchial-asthma

To determine whether acute changes in lung volumes in asthma are accurately measured by body plethysmography, we induced acute changes in lung mechanics with acetylcholine in nine asthmatic patients and with salbutamol in six others. Total lung capacity (TLC) was measured with a body plethysmograph and derived from mouth pressure vs. box volume (Vbox) changes (TLCm) or esophageal pressure vs. Vbox changes (TLCes). In six patients (4 after acetylcholine) TLCm was significantly (P less than 0.05) different from prechallenge values (differences ranged from 0.29 to 1.55 liters), but TLCes did not change. In three additional patients both TLCm (mean difference 0.62 liter) and TLCes (mean difference 0.43 liter) changed (P less than 0.05), but no changes occurred in six others. An electrical analog of the lung demonstrates in the presence of intrathoracic airway obstruction overestimation of thoracic gas volume and TLC. This is due to the presence of a compliant extrathoracic airway that acts as a shunt impedance. The magnitude of the overestimation of TGV appears to depend on the distensibility of the extrathoracic airway and the degree of airway obstruction. We conclude that the plethysmographic method may introduce important errors in lung volume measurements in the obstructive syndrome, especially a severe one. Some of previously reported acute increases in TLC in asthmatics may be artifactual. </jats:p

Non-invasive ventilation and sleep.

In this paper, we review the effects of nocturnal mechanical ventilation on sleep. Indeed, although non-invasive assisted ventilation during sleep has been applied extensively, the exact effects of this treatment on sleep quality have not been thoroughly studied. In patients with severe chronic obstructive pulmonary disease and severe restrictive ventilatory defects, the resulting respiratory failure is aggravated by the specific effects of sleep on respiration. Non-invasive mechanical ventilation can lead to improvements in both ventilation and sleep quality. However, this is not always the case. Moreover, sleep-related leaks may jeopardize the efficiency of the ventilatory assistance which in turn may result in a deterioration in sleep quality. Non-invasive mechanical ventilation, if applied during sleep, should require a monitoring procedure during sleep with the aim of obtaining the best possible effects both on ventilation and on sleep quality

Sleep fragmentation: comparison of two definitions of short arousals during sleep in OSAS patients.

The measurement of arousals during sleep is useful to quantify sleep fragmentation. The criteria for electroencephalography (EEG) arousals defined by the American Sleep Disorders Association (ASDA) have recently been criticized because of lack of interobserver agreement. The authors have adopted a scoring method that associates the increase in chin electromyography (EMG) with the occurrence of an alpha-rhythm in all sleep stages (Université Catholique de Louvain (UCL) definition of arousals). The aim of the present study was to compare the two scoring definitions in terms of agreement and repeatability and the time taken for scoring in patients with obstructive sleep apnoea syndrome (OSAS) of varying severity. Two readers using both ASDA and UCL definitions scored twenty polysomnographies (PSGs) each on two occasions. The PSGs were chosen retrospectively to represent a wide range of arousal index (from 6-82) in OSAS patients. There was no difference in the arousal indices between readers and between scoring methods. The mean+/-SD difference between the two definitions (the bias) was 1.1+/-3.76 (95% confidence interval: -0.66-2.86). There was a strong linear relationship between the arousal index scored with the two definitions (r=0.981, p<0.001). Mean+/-SD scoring duration was significantly shorter for UCL than for ASDA definitions (18.5+/-5.4 versus 25.3+/-6.6 min, p<0.001). In conclusion, it has been found that in obstructive sleep apnoea syndrome patients, the American Sleep Disorders Association and Université Catholique de Louvain definitions were comparable in terms of agreement and repeatability