Background Hospitalisations and their sequelae comprise key morbidities in the natural history of chronic obstructive pulmonary disease (COPD). A study was undertaken to examine the associations between lung function impairment and COPD hospitalisation, and COPD hospitalisation and mortality. Methods The analysis included a population-based sample of 20 571 participants with complete demographic, lung function, smoking, hospitalisation and mortality data, with 10-year median follow-up. Participants were classified by prebronchodilator lung function according to the modified Global Initiative on Obstructive Lung Disease (GOLD) criteria. Hospitalisations were defined by the presence of a COPD discharge diagnosis (ICD-9 codes 490e496). Incidence rate ratios (IRR) of COPD admissions and hazard ratios (HR) of mortality with respective 95% CI were calculated, adjusted for potential confounders. Results The prevalence of modified GOLD categories was normal (36%), restricted (15%), GOLD stage 0 (22%), GOLD stage 1 (13%), GOLD stage 2 (11%) and GOLD stages 3 or 4 (3%). Adjusted IRRs (and 95% CI) indicated an increased risk of COPD hospitalisation associated with each COPD stage relative to normal lung function: 4.7 (3.7 to 6.1), 2.1 (1.6 to 2.6), 3.2 (2.6 to 4.0), 8.0 (6.4 to 10.0) and 25.5 (19.5 to 33.4) for the restricted, GOLD stage 0, GOLD stage 1, GOLD stage 2 and GOLD stages 3 or 4, respectively. Hospitalisation for COPD increased the risk of subsequent mortality (HR 2.7, 95% CI 2.5 to 3.0), controlling for severity, number of prior hospitalisations and other potential confounders. The increase in mortality associated with admission was very similar across the modified GOLD stages. Conclusions COPD severity was associated with a higher rate of severe exacerbations requiring hospitalisation, although severe exacerbations at any stage were associated with a higher risk of short-term and long-term all-cause mortality.Chronic obstructive pulmonary disease (COPD) is responsible for a significant medical and economic burden in the USA and is expected to be the third leading cause of worldwide mortality by the year 2020.1 In 2000 in the USA 726 000 people were hospitalised for an exacerbation of COPD, with people aged >65 years responsible for more than one-half of these.2 Almost 120 000 people in the USA died with COPD as the underlying cause of death in 2000.2 However, this number may actually be higher because many decedents with COPD have their deaths attributed to other causes, 3 and serious comorbid conditions are common in this population. 4e6 Acute exacerbations of COPD frequently result in hospital admission and account for a large proportion of the clinical, economical and social impact of this disease, including an increased risk of mortality. Impaired lung function has been identified as a risk factor of hospital admission due to a COPD exacerbation in several studies including different settings, designs and methods, and independent of respiratory symptoms, quality of life or blood gas exchange.7e...

Seasonal changes in physical activity in daily life (PADL) of patients with Chronic Obstructive Pulmonary Disease (COPD) living in regions of the world with contrasting (i.e., mild or marked) weather variations have not been yet investigated. We aimed to quantify PADL and compare its variability caused by seasonality in patients with COPD who live in world regions with different summer-winter climatic variations (i.e. Londrina, Brazil and Leuven, Belgium). In a longitudinal, prospective and observational study, patients with COPD from Brazil and Belgium wore the SenseWear Armband for 7 days in summer and 7 days in winter. Active time (≥2METs) was the primary outcome. PADL data were matched day-by-day with weather information. Regarding the two assessment moments, median (min;max) temperatures were 11 (-5.5;27.2)°C in Leuven and 21 (7;27)°C in Londrina. Patients in Brazil (n = 19, 69 ± 7 years, FEV 47 ± 15%) and Belgium (n = 18, 69 ± 6 years, FEV 50 ± 15%) decreased their active time in winter compared to summer (p < 0.05), and this reduction was more pronounced in Brazil (p = 0.01, between group). Mean, minimum and maximum temperature, daylight duration and relative humidity were significantly related to active time. Patients with COPD decrease their PADL in winter even in a region with milder climatic variation.

Peak flow variability in childhood and body mass index in adult life MET, Metabolic equivalent of task; obs, observations. *Age was centered at the youngest age, 9.2 y, to facilitate interpretation of the main effect coefficient of PFvar. METs were used as an ordinal variable at each survey where the first category was 0 MET h/wk, the second category was between 1 and 40 MET h/wk, and the third category was >40 MET h/wk (see text). àReference category: both non-Hispanic white parents.

No abstract