Patients with inherited alpha 1-antitrypsin (AAT) deficiency (ZZ-AATD) and severe chronic obstructive pulmonary disease (COPD) frequently experience exacerbations. We postulated that inhalation of... Show morePatients with inherited alpha 1-antitrypsin (AAT) deficiency (ZZ-AATD) and severe chronic obstructive pulmonary disease (COPD) frequently experience exacerbations. We postulated that inhalation of nebulised AAT would be an effective treatment.We randomly assigned 168 patients to receive twice-daily inhalations of 80 mg AAT solution or placebo for 50 weeks. Patients used an electronic diary to capture exacerbations. The primary endpoint was time from randomisation to the first event-based exacerbation. Secondary endpoints included change in the nature of the exacerbation as defined by the Anthonisen criteria. Safety was also assessed.Time to first moderate or severe exacerbation was a median of 112 days (interquartile range (IQR) 40-211 days) for AAT and 140 days (IQR 72-142 days) for placebo (p=0.0952). The mean yearly rate of all exacerbations was 3.12 in the AAT-treated group and 2.67 in the placebo group (p=0.31). More patients receiving AAT reported treatment-related treatment-emergent adverse events compared to placebo (57.5% versus 46.9%, respectively) and they were more likely to withdraw from the study. After the first year of the study, when modifications to the handling of the nebuliser were introduced, the rate of safety events in the AAT-treated group dropped to that of the placebo group.We conclude that in AATD patients with severe COPD and frequent exacerbations, AAT inhalation for 50 weeks showed no effect on time to first exacerbation but may have changed the pattern of the episodes. Show less
Chronic obstructive pulmonary disease (COPD) is the leading cause of respiratory mortality worldwide. Genetic risk loci provide new insights into disease pathogenesis. We performed a genome-wide... Show moreChronic obstructive pulmonary disease (COPD) is the leading cause of respiratory mortality worldwide. Genetic risk loci provide new insights into disease pathogenesis. We performed a genome-wide association study in 35,735 cases and 222,076 controls from the UK Biobank and additional studies from the International COPD Genetics Consortium. We identified 82 loci associated with P < 5 x 10(-8); 47 of these were previously described in association with either COPD or population-based measures of lung function. Of the remaining 35 new loci, 13 were associated with lung function in 79,055 individuals from the SpiroMeta consortium. Using gene expression and regulation data, we identified functional enrichment of COPD risk loci in lung tissue, smooth muscle, and several lung cell types. We found 14 COPD loci shared with either asthma or pulmonary fibrosis. COPD genetic risk loci clustered into groups based on associations with quantitative imaging features and comorbidities. Our analyses provide further support for the genetic susceptibility and heterogeneity of COPD. Show less
Significant heterogeneity of clinical presentation and disease progression exists within chronic obstructive pulmonary disease (COPD). Although FEV1 inadequately describes this heterogeneity, a... Show moreSignificant heterogeneity of clinical presentation and disease progression exists within chronic obstructive pulmonary disease (COPD). Although FEV1 inadequately describes this heterogeneity, a clear alternative has not emerged. The goal of phenotyping is to identify patient groups with unique prognostic or therapeutic characteristics, but significant variation and confusion surrounds use of the term "phenotype" in COPD. Phenotype classically refers to any observable characteristic of an organism, and up until now, multiple disease characteristics have been termed COPD phenotypes. We, however, propose the following variation on this definition: "a single or combination of disease attributes that describe differences between individuals with COPD as they relate to clinically meaningful outcomes (symptoms, exacerbations, response to therapy, rate of disease progression, or death)." This more focused definition allows for classification of patients into distinct prognostic and therapeutic subgroups for both clinical and research purposes. Ideally, individuals sharing a unique phenotype would also ultimately be determined to have a similar underlying biologic or physiologic mechanism(s) to guide the development of therapy where possible. It follows that any proposed phenotype, whether defined by symptoms, radiography, physiology, or cellular or molecular fingerprint will require an iterative validation process in which "candidate" phenotypes are identified before their relevance to clinical outcome is determined. Although this schema represents an ideal construct, we acknowledge any phenotype may be etiologicaxlly heterogeneous and that any one individual may manifest multiple phenotypes. We have much yet to learn, but establishing a common language for future research will facilitate our understanding and management of the complexity implicit to this disease. Show less
Background: Genetic factors play a role in chronic obstructive pulmonary disease (COPD) but are poorly understood. A number of candidate genes have been proposed on the basis of the pathogenesis of... Show moreBackground: Genetic factors play a role in chronic obstructive pulmonary disease (COPD) but are poorly understood. A number of candidate genes have been proposed on the basis of the pathogenesis of COPD. These include the matrix metalloproteinase (MMP) genes which play a role in tissue remodelling and fit in with the protease-antiprotease imbalance theory for the cause of COPD. Previous genetic studies of MMPs in COPD have had inadequate coverage of the genes, and have reported conflicting associations of both single nucleotide polymorphisms (SNPs) and SNP haplotypes, plausibly due to under-powered studies. Methods: To address these issues we genotyped 26 SNPs, providing comprehensive coverage of reported SNP variation, in MMPs-1, 9 and 12 from 977 COPD patients and 876 non-diseased smokers of European descent and evaluated their association with disease singly and in haplotype combinations. We used logistic regression to adjust for age, gender, centre and smoking history. Results: Haplotypes of two SNPs in MMP-12 (rs652438 and rs2276109), showed an association with severe/very severe disease, corresponding to GOLD Stages III and IV. Conclusions: Those with the common A-A haplotype for these two SNPs were at greater risk of developing severe/very severe disease (p = 0.0039) while possession of the minor G variants at either SNP locus had a protective effect (adjusted odds ratio of 0.76; 95% CI 0.61-0.94). The A-A haplotype was also associated with significantly lower predicted FEV1 (42.62% versus 44.79%; p = 0.0129). This implicates haplotypes of MMP-12 as modifiers of disease severity. Show less
