In 2001 the Global Initiative for Chronic Obstructive Lung Disease (GOLD) committee published its first consensus report. At that time the authors suggested that the assessment of chronic obstructive pulmonary disease (COPD) should be primarily based on the extent of airflow limitation. In the following years, evidence accumulated that COPD is a complex and heterogeneous disease and that airflow limitation is not closely correlated to a variety of patient-related outcomes. These findings, and the intent to create a more comprehensive system to better reflect the situation of an individual patient, were the basis for a novel concept recently published by GOLD. Now, the assessment is no longer based on the extent of airflow limitation alone; in addition, the patient's exacerbation history and symptoms are taken into account. Based on the severity of symptoms and the exacerbation risk, four categories (A, B, C and D) were defined.
Since then, this novel assessment scheme has been studied in several existing cohorts, ranging from more than 2000 clinically stable COPD patients in the ECLIPSE study (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints), over a more broadly composed cohort of 4000 smokers from the COPDGene study, to population samples from Copenhagen …
Chronic obstructive pulmonary disease (COPD), low lung function independent of diagnosis and markers of inflammation are all associated with increased morbidity and mortality. Microalbuminuria, reflecting endothelial dysfunction, could be a relevant inflammatory marker of potential systemic effects of COPD. We hypothesised that there was a positive association between microalbuminuria and mortality in individuals with COPD.
We conducted a 12-year follow-up study of 3129 participants in the second survey of the Nord-Trøndelag Health Study (HUNT), Norway. At baseline, albuminuria was analysed in three urine samples and spirometry was performed. Among the participants, 136 had COPD and microalbuminuria, defined as a urinary albumin/creatinine ratio between 2.5 and 30.0 mg·mmol–1. The main outcome measures were hazard ratio of all-cause mortality according to microalbuminuria.
Compared to those with COPD without microalbuminuria, the adjusted hazard ratio for all-cause mortality in those with COPD and microalbuminuria was 1.54, 95% CI 1.16–2.04. This result was similar after excluding cardiovascular disease at baseline. Classifying COPD severity by Global Initiative for Chronic Obstructive Lung Disease, there was a positive association trend with increasing severity stages.
Microalbuminuria is associated with all-cause mortality in individuals with COPD and could be a relevant tool in identification of patients with poor prognosis.
The aim of this study was to determine the added value of measuring the forced expiratory flow at 25–75% of forced vital capacity (FVC) (FEF25–75%) and flow when 75% of FVC has been exhaled (FEF75%) over and above the measurement of the forced expiratory volume in 1 s (FEV1), FVC and FEV1/FVC ratio.
We used spirometric measurements of FEV1, FVC and FEF25–75% from 11 654 white males and 11 113 white females, aged 3–94 years, routinely tested in the pulmonary function laboratories of four tertiary hospitals. FEF75% was available in 8254 males and 7407 females. Predicted values and lower limits of normal, defined as the fifth percentile, were calculated for FEV1, FVC, FEV1/FVC ratio, FEF25–75% and FEF75% using prediction equations from the Global Lung Function Initiative.
There was very little discordance in classifying test results. FEF25–75% and FEF75% were below the normal range in only 2.75% and 1.29% of cases, respectively, whereas FEV1, FVC and FEV1/FVC ratio were within normal limits. Airways obstruction went undetected by FEF25–75% in 2.9% of cases and by FEF75% in 12.3% of cases.
Maximum mid-expiratory flow and flow towards the end of the forced expiratory manoeuvre do not contribute usefully to clinical decision making over and above information from FEV1, FVC and FEV1/FVC ratio.