Polysomnographic features of low arousal threshold in overlap syndrome involving obstructive sleep apnea and chronic obstructive pulmonary disease.

PURPOSE: In patients with overlap syndrome (OVS), the pathophysiologies of obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease can interact with one another. Focusing on low arousal threshold, the authors evaluated polysomnographic features of OVS patients. METHODS: This retrospective, multicenter study was conducted at three hospitals in Japan. Patients aged ≥ 60 years who underwent polysomnography and pulmonary function testing were reviewed. Severity of airflow limitation (AFL) was classified according to the Global Initiative for Chronic Obstructive Lung Disease criteria. Low arousal threshold was predicted based on the following polysomnography features: lower apnea-hypopnea index (AHI); higher nadir oxygen saturation, and larger hypopnea fraction of total respiratory events. These features were compared among patients with only OSA (n = 126), OVS with mild AFL (n = 16), and OVS with moderate/severe AFL (n = 22). RESULTS: A low arousal threshold was more frequently exhibited by OVS patients with moderate/severe AFL than by those with OSA only (p = 0.016) and OVS with mild AFL (p = 0.026). As forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) decreased in OVS patients, the mean length of apnea decreased (r = 0.388, p = 0.016), hypopnea fractions increased (r = - 0.337, p = 0.039), and AHI decreased (r = 0.424, p = 0.008). FEV1/FVC contributed to low arousal threshold independent of age, sex, smoking history, hospital, or body mass index in all subjects (OR 0.946 [95% CI 0.909-0.984]) and in OVS patients (OR 0.799 [95% CI 0.679-0.940]). CONCLUSIONS: This study first described peculiar polysomnographic features in OVS patients with moderate/severe AFL, suggesting a high prevalence of low arousal threshold.

High affinity sugar ligands of C-type lectin receptor langerin.

BACKGROUND: Langerin, a C-type lectin receptor (CLR) expressed in a subset of dendritic cells (DCs), binds to glycan ligands for pathogen capture and clearance. Previous studies revealed that langerin has an unusual binding affinity toward 6-sulfated galactose (Gal), a structure primarily found in keratan sulfate (KS). However, details and biological outcomes of this interaction have not been characterized. Based on a recent discovery that the disaccharide L4, a KS component that contains 6-sulfo-Gal, exhibits anti-inflammatory activity in mouse lung, we hypothesized that L4-related compounds are useful tools for characterizing the langerin-ligand interactions and their therapeutic application. METHODS: We performed binding analysis between purified long and short forms of langerin and a series of KS disaccharide components. We also chemically synthesized oligomeric derivatives of L4 to develop a new high-affinity ligand of langerin. RESULTS: We show that the binding critically requires the 6-sulfation of Gal and that the long form of langerin displays higher affinity than the short form. The synthesized trimeric (also designated as triangle or Tri) and polymeric (pendant) L4 derivatives displayed over 1000-fold higher affinity toward langerin than monomeric L4. The pendant L4, but not the L4 monomer, was found to effectively transduce langerin signaling in a model cell system. CONCLUSIONS: L4 is a specific ligand for langerin. Oligomerization of L4 unit increased the affinity toward langerin. GENERAL SIGNIFICANCE: These results suggest that oligomeric L4 derivatives will be useful for clarifying the langerin functions and for the development of new glycan-based anti-inflammatory drugs.

A keratan sulfate disaccharide prevents inflammation and the progression of emphysema in murine models.

Emphysema is a typical component of chronic obstructive pulmonary disease (COPD), a progressive and inflammatory airway disease. However, no effective treatment currently exists. Here, we show that keratan sulfate (KS), one of the major glycosaminoglycans produced in the small airway, decreased in lungs of cigarette smoke-exposed mice. To confirm the protective effect of KS in the small airway, a disaccharide repeating unit of KS designated L4 ([SO3--6]Galß1-4[SO3--6]GlcNAc) was administered to two murine models: elastase-induced-emphysema and LPS-induced exacerbation of a cigarette smoke-induced emphysema. Histological and microcomputed tomography analyses revealed that, in the mouse elastase-induced emphysema model, administration of L4 attenuated alveolar destruction. Treatment with L4 significantly reduced neutrophil influx, as well as the levels of inflammatory cytokines, tissue-degrading enzymes (matrix metalloproteinases), and myeloperoxidase in bronchoalveolar lavage fluid, suggesting that L4 suppressed inflammation in the lung. L4 consistently blocked the chemotactic migration of neutrophils in vitro. Moreover, in the case of the exacerbation model, L4 inhibited inflammatory cell accumulation to the same extent as that of dexamethasone. Taken together, L4 represents one of the potential glycan-based drugs for the treatment of COPD through its inhibitory action against inflammation.

Influence of SIGLEC9 polymorphisms on COPD phenotypes including exacerbation frequency.

BACKGROUND AND OBJECTIVE: The exacerbation-prone phenotype of COPD is particularly important, as exacerbations lead to poor quality of life and disease progression. We previously found that COPD patients who lack Siglec-14, a myeloid cell protein that recognizes bacteria and triggers inflammatory responses, are less prone to exacerbation. We hypothesized that the variations in other SIGLEC genes could also influence COPD exacerbation frequency, and investigated the association between SIGLEC9 polymorphisms and the exacerbation-prone phenotype of COPD. METHODS: We examined whether SIGLEC9 polymorphisms affect the frequency of COPD exacerbation in 135 subjects within our study population, and also analysed the correlation between the genotypes and the severity of airflow obstruction and emphysema in 362 Japanese smokers including 244 COPD patients. The association between these single nucleotide polymorphisms (SNPs) and COPD phenotypes were also assessed in a Caucasian population of ECLIPSE study. The effects of these coding SNPs (cSNPs) on Siglec-9 protein functions were analysed using in vitro assays. RESULTS: The G allele of rs2075803 and rs2075803 G/rs2258983 A(GA) haplotype in SIGLEC9 was associated with higher frequency of exacerbations and the extent of emphysema in COPD. These results did not replicate in the ECLIPSE study. A myeloid cell line expressing the Siglec-9 variant corresponding to GA haplotype produced more TNF-α than the one expressing the variant corresponding to the other major haplotype. CONCLUSION: The SIGLEC9 rs2075803 G/rs2258983 A haplotype, which corresponds to a Siglec-9 variant that is less effective at suppressing inflammatory response, may be a risk factor for the development of emphysema.

Atrial and Ventricular Arrhythmia-Associated Factors in Stable Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: Supraventricular and ventricular premature complexes (SVPC and VPC, respectively) are associated with chronic obstructive pulmonary disease (COPD) and with increased mortality in COPD patients. However, there are few reports on the causes of arrhythmia in COPD patients. OBJECTIVES: This study explores the associations between cardiopulmonary dysfunction and COPD by comparing patients with defined arrhythmias (>100 beats per 24 h) and those without, based on 24-hour electrocardiogram (ECG) recordings. METHODS: Patients with arrhythmia underwent a 24-hour ECG and subsequent pulmonary function tests, computed tomography, ECG, 6-min walk test (6MWT), and BODE (body mass index, airflow obstruction, modified Medical Research Council Dyspnoea Scale, exercise capacity) index calculation. RESULTS: Of 103 study patients (71 COPD patients and 32 at-risk patients), 36 had VPC, 45 had SVPC, 20 had both, and 42 had neither. The predicted post-bronchodilator forced expiratory volume in 1 s, the proportion of low-attenuation area on computed tomography, and BODE index values were significantly worse in the SVPC and VPC groups compared with the corresponding reference groups. Patients in the VPC group showed significantly increased right ventricular pressure and increased desaturation in the 6MWT compared with the reference group. In the multivariate analyses, bronchodilator use was a significant risk factor in the SVPC group, whereas in the VPC group, all parameters of the BODE index except for the dyspnoea score were identified as risk factors. CONCLUSIONS: Increased SVPC might be caused by bronchodilator use, whereas increased VPC is likely related to the peculiar pathophysiology of COPD.

[Management of older adults with COPD].

In older adults, the clinical condition of COPD is complicated and treatment often becomes difficult, because of existence of multimorbidity, such as nutritional deficiencies, thinness, sarcopenia, osteoporosis, cardiovascular disease, depression and cognitive impairment. Consideration based on each of coexistence is needed in the management of older adults with COPD. In end period of COPD, sleep disorder, depressive state and decline of ADL are often shown, in addition to the respiratory symptoms, such as dyspnea, cough and sputum. Financial strain for the nursing cost and medical equipment cost tend to become big year by year, utilization of social resources (i.e. application of respiratory disabilities and an insurance of the elderly care) is need to be considered.

Diagnostic Values For Club Cell Secretory Protein (CC16) in Serum of Patients of Combined Pulmonary Fibrosis and Emphysema.

Combined pulmonary fibrosis and emphysema (CPFE) is an under-recognized syndrome for which the diagnostic use of serum biomarkers is an attractive possibility. We hypothesized that CC16 and/or TGF-ß1 or combinations with other biomarkers are useful for diagnosing CPFE. Patients with respiratory symptoms and a smoking history, with or without chronic obstructive pulmonary disease, were divided into the following three groups according to findings of high-resolution computed tomography of the chest: controls without either emphysema or fibrosis, patients with emphysema alone, and patients compatible with the diagnosis of CPFE. Serum concentrations of CC16, TGF-ß1, SP-D, and KL-6 were measured in patients whose condition was stable for at least 3 months. To investigate changes in biomarkers of lung fibrosis in patients with a life-long smoking history, additional measurements were performed on the patients with idiopathic pulmonary fibrosis (IPF) of smoking history. The mean age of the first three groups was 68.0 years, whereas that of the IPF group was 71.8 years, and the groups contained 36, 115, 27, and 10 individuals, respectively. The serum concentration of CC16 in the four groups was 5.67 ± 0.42, 5.66 ± 0.35, 9.38 ± 1.04 and 22.15 ± 4.64 ng/ml, respectively, indicating that those patients with lung fibrosis had a significantly higher concentration. The combined use of CC16, SP-D, and KL-6 provided supportive diagnosis in conjunction with radiological imaging in diagnosis of CPFE. We conclude that a combination of biomarkers including CC16 could provide useful information to screen and predict the possible diagnosis of CPFE.

Predictors of chronic obstructive pulmonary disease exacerbations.

PURPOSE OF REVIEW: A frequent-exacerbation phenotype of chronic obstructive pulmonary disease (COPD) exists that is independent of disease severity. Establishment of methods to predict 'frequent exacerbators' is critical. The purpose of this review is to critically assess the recent literature regarding predicting COPD exacerbations, and to provide recommendations for future research. RECENT FINDINGS: Although there are many studies in which inflammatory biomarkers have been used in an attempt to predict future exacerbations, it is likely that these biomarkers represent a consequence rather than the cause. Genetic predictors are involved in causal pathways. Thus, genetics should be investigated in order to understand the exacerbation mechanism and to develop new therapeutic approaches. Some single nucleotide-type genetic polymorphisms are associated with exacerbations, and the individuals with genotypes protective against infection are less susceptible to exacerbations. In contrast, we reported that loss of Siglec-14, a lectin likely involved in host defense, was associated with a reduced COPD exacerbation risk. SUMMARY: We should take into consideration that a protein involved in host defense such as Siglec-14, that could also trigger exaggerated response, might also generate unwanted local and systemic inflammation, which could be detrimental to a host and could generate COPD with a frequent-exacerbation phenotype, its progression, and its comorbidities.

Association of group component genetic variations in COPD and COPD exacerbation in a Japanese population.

BACKGROUND AND OBJECTIVE: Vitamin D supplementation can decrease the vulnerability to pulmonary infections. Therefore, it is speculated that the genes related to vitamin D metabolism are associated with an exacerbation-prone phenotype in chronic obstructive pulmonary disease (COPD). Because genetic variations of group component (GC) affect immunological capacity and serum vitamin D concentration, they could also affect the susceptibility to COPD exacerbation and the disease progression. We investigated the association between GC genetic variations and COPD and its exacerbation frequency in a Japanese population. METHODS: We performed genotype analysis of 361 COPD patients and 219 controls to identify two coding single nucleotide polymorphisms of GC, rs4588 and rs7041. We examined whether these polymorphisms were associated with the frequency of COPD exacerbation and analysed the correlation between the genotypes, COPD, emphysema severity and COPD progression, namely, the annual decline in airflow obstruction and diffusing capacity. RESULTS: Subjects with a C allele at rs4588 exhibited a higher frequency of exacerbations (P = 0.0048), greater susceptibility to chronic obstructive pulmonary disease (P = 0.0003), and emphysema (P = 0.0029), and a tendency for rapid decline of airflow obstruction (P = 0.0927). CONCLUSIONS: GC variations may affect exacerbation susceptibility, possibly leading to COPD worsening and its progression.

Loss of Siglec-14 reduces the risk of chronic obstructive pulmonary disease exacerbation.

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality worldwide. COPD exacerbation, or episodic worsening of symptoms, often results in hospitalization and increased mortality rates. Airway infections by new bacterial strains, such as nontypeable Haemophilus influenzae (NTHi), are a major cause of COPD exacerbation. NTHi express lipooligosaccharides that contain sialic acids, and may interact with Siglec-14, a sialic acid recognition protein on myeloid cells that serves as an activating signal transduction receptor. A null allele polymorphism in SIGLEC14 may attenuate the inflammatory responses to NTHi by eliminating Siglec-14 expression. We asked if the loss of Siglec-14 attenuates the inflammatory response by myeloid cells against NTHi, and if the SIGLEC14-null polymorphism has any effect on COPD exacerbation. We found that NTHi interacts with Siglec-14 to enhance proinflammatory cytokine production in a tissue culture model. Inhibitors of the Syk tyrosine kinase suppress this response. Loss of Siglec-14, due to SIGLEC14-null allele homozygosity, is associated with a reduced risk of COPD exacerbation in a Japanese patient population. Taken together, Siglec-14 and its downstream signaling pathway facilitate the "infection-inflammation-exacerbation" axis of COPD disease progression, and may represent promising targets for therapeutic intervention.

A single dose of lipopolysaccharide into mice with emphysema mimics human chronic obstructive pulmonary disease exacerbation as assessed by micro-computed tomography.

Chronic obstructive pulmonary disease (COPD), manifested as emphysema and chronic airway obstruction, can be exacerbated by bacterial and viral infections. Although the frequency of exacerbations increases as the disease progresses, the mechanisms underlying this phenomenon are largely unknown, and there is a need for a simple in vivo exacerbation model. In this study, we compared four groups of mice treated with PBS alone, elastase alone, LPS alone, and elastase plus LPS. A single intratracheal administration of LPS to mice with elastase-induced emphysema provoked infiltration of inflammatory cells, especially CD8(+) T cells, into alveolar spaces and increased matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, and perforin production in bronchoalveolar lavage fluid at the acute inflammatory phase compared with the other groups. We also measured the percentage of low-attenuation area (LAA%) in the above mice using micro-computed X-ray tomography. The LAA% was the most sensitive parameter for quantitative assessments of emphysema among all the parameters evaluated. Using the parameter of LAA%, we found significantly more severe alveolar destruction in the group treated with elastase plus LPS compared with the other groups during long-term longitudinal observations. We built three-dimensional images of the emphysema and confirmed that the lungs of elastase plus LPS-treated mice contained larger emphysematous areas than mice treated with elastase alone. Although human exacerbation of COPD is clinically and pathologically complicated, this simple mouse model mimics human cases to some extent and will be useful for elucidating its mechanism and developing therapeutic strategies.

Long-term oxygen therapy in Japan: history, present status, and current problems.

Historically, the progress of long term-oxygen therapy (LTOT) in Japan has been characterized by collaboration among academic groups, policy makers, and industrial companies. The public health insurance program has covered the cost of LTOT since 1985. Thomas Petty's group in Denver enthusiastically carried out the public implementation of LTOT and conveyed the concept of pulmonary rehabilitation for the processing with LTOT. Although the target diseases of LTOT in Japan tended to be chronic obstructive pulmonary disease or sequelae of primary lung tuberculosis, it was soon applied for cardiac diseases as well as other pulmonary diseases. Together with increasing medical costs for geriatric patients, the political conversion from hospital based care of a traditional style to home care system has been performed, with two background reasons: the improvement of quality of life of patients and the reduction of the medical expense. Presently, LTOT plays a pivotal role in the successful implementation of home respiratory care for elderly patients. In addition, this promotes comprehensive pulmonary rehabilitation, a team approach, and close liaisons between primary care and hospitals. Currently, the total number of patients using LTOT exceeds 150,000. In Japan, LTOT resulted in an advancement in the medical care as well as in administrative decision to introduce it as a nationwide system after analyzing the results of opinion polls of patients with respiratory failure. However, the recent great earthquake in East Japan revealed that many unresolved problems remain for these patients, and these issues are of great concern.

α1,6-Fucosyltransferase (Fut8) is implicated in vulnerability to elastase-induced emphysema in mice and a possible non-invasive predictive marker for disease progression and exacerbations in chronic obstructive pulmonary disease (COPD).

Fut8 (α1,6-Fucosyltransferase) heterozygous knock-out (Fut8(+/-)) mice had an increased influx of inflammatory cells into the lungs, and this was associated with an up-regulation of matrix metalloproteinases, MMP-2 and MMP-9, after treatment with porcine pancreatic elastase (PPE), exhibiting an emphysema-prone phenotype as compared with wild type mice (Fut8(+/+)). The present data as well as our previous data on cigarette-smoke-induced emphysema [8] led us to hypothesize that reduced Fut8 levels leads to COPD with increased inflammatory response in humans and is associated with disease progression. To test this hypothesis, symptomatic current or ex-smokers with stable COPD or at risk outpatients were recruited. We investigated the association between serum Fut8 activity and disease severity, including the extent of emphysema (percentage of low-attenuation area; LAA%), airflow limitation, and the annual rate of decline in forced expiratory volume in 1 s (FEV(1)). Association with the exacerbation of COPD was also evaluated over a 3-year period. Serum Fut8 and MMP-9 activity were measured. Fut8 activity significantly increased with age among the at risk patients. In the case of COPD patients, however, the association was not clearly observed. A faster annual decline of FEV(1) was significantly associated with lower Fut8 activity. Patients with lower Fut8 activity experienced exacerbations more frequently. These data suggest that reduced Fut8 activity is associated with the progression of COPD and serum Fut8 activity is a non-invasive predictive biomarker candidate for progression and exacerbation of COPD.

Association between genetic variations in surfactant protein d and emphysema, interstitial pneumonia, and lung cancer in a Japanese population.

Surfactant protein D (SFTPD) is a lung-specific anti-inflammatory factor that antagonizes inflammation by inhibiting oxidative stress and stimulating innate immunity. Variations in SFTPA2 and SFTPB, genes for other surfactant proteins, have been associated with lung cancer. We therefore investigated associations between SFTPD variations and lung cancer as well as emphysema and interstitial pneumonia, which are characterized by chronic inflammation from which lung cancer often arises. DNA from 1342 autopsy samples, including those from 140 subjects with lung cancer, was investigated. The single nucleotide polymorphism (SNP) rs721917, which results in methionine being exchanged for threonine at amino acid 11 (the Met11Thr variation), tended to be associated with emphysema and was associated with interstitial pneumonia and lung cancer. A haplotype analysis revealed that the haplotypes associated with emphysema and lung cancer differed from that associated with interstitial pneumonia, suggesting a differential role for SFTPD in the development of these diseases. A mediating analysis did not reveal a mediating effect exerted by emphysema or interstitial pneumonia on lung cancer. Our results suggested that SFTPD plays a role in the development of lung cancer and that the role for lung cancer may differ from that for interstitial pneumonia.

Association of serotonin transporter gene variation with smoking, chronic obstructive pulmonary disease, and its depressive symptoms.

A serotonin transporter gene, SLC6A4, is thought to be related to nicotine dependence and depression, one of the comorbidities of chronic obstructive pulmonary disease (COPD). To investigate the association between SLC6A4 variation and tobacco consumption, susceptibility to COPD, and depression status. In all, 247 patients with COPD and 119 control subjects were genotyped for 5 tag single-nucleotide polymorphisms (SNPs) of SLC6A4. We analyzed the correlation between these genotypes and COPD, using the results of a pulmonary function test or chest computed tomography; data on tobacco consumption (pack-years); and the depression score based on the hospital anxiety and depression scale (HADS) after adjusting for age, gender, and smoking status (and pack-years, when appropriate). The rare allele rs2020936 was significantly associated with COPD incidence in the trend model (P = 0.003; odds ratio, 2.20; 95% confidence interval, 1.31-3.74). This allele was also associated with the number of pack-years (P = 0.026). The major allele of another SNP of SLC6A4, namely rs3794808, correlated with the HADS depression score (P = 0.016). We conclude that SLC6A4 variation affects COPD pathogenesis, and this effect depends partly on tobacco consumption. SLC6A4 variation also affects depressive symptoms. SLC6A4 could be modified to prevent COPD and treat the depressive symptoms of COPD.

Association of fucosyltransferase 8 (FUT8) polymorphism Thr267Lys with pulmonary emphysema.

The fucosyltransferase 8 gene (FUT8) encodes an enzyme that transfers fucose to the innermost N-acetylglucosamine unit of N-glycan chains. Recent study showed that fut8-deficient mice develop pathological and physiological phenotypes resembling pulmonary emphysema (PE). The role of FUT8 in human PE is not known. A non-synonymous single-nucleotide polymorphism at the amino-acid position of 267 in FUT8 (rs35949016; C/A, C allele=Thr, A allele=Lys) was genotyped in a total of 1149 consecutive autopsies of elderly Japanese. A following study included 182 outpatients with chronic obstructive pulmonary disease, whose emphysematous changes were assessed quantitatively as the percentage of low attenuation area (%LAA) by high-resolution computed tomography. PE was detected in 163 of 1149 autopsy subjects (14.2%). Comparison of patient with vs without PE indicated that the FUT8 A allele was associated with PE (AA+AC vs CC; odds ratio=1.74, 95% confidence intervals=1.19-2.56, P=0.005). In the clinical study, presence of the FUT8 A allele significantly correlated with %LAA after adjustment (AA+AC vs CC=37.5±14.7 vs 32.7±13.9, P=0.02). The FUT8 gene Thr267Lys polymorphism is associated with human PE, and the Lys allele is the risk. The core fucosylation might be involved in the molecular pathogenesis of human PE.

[Concept of teamwork and inter- and intra-connection for better management of COPD patients].

The elderly population makes up a majority of the patients with chronic obstructive pulmonary disease (COPD), and more than 90 % of these patients have mild or moderate severity of COPD. Furthermore, in general, most severe cases receiving occasional long-term oxygen therapy may show a gradual decline in the activity of daily living and/or a cognitive impairment during the clinical course. These conditions together with the fact that in most cases the medical facility is far from patient's home prevent them from regularly visiting chest physicians at a large community hospital; therefore, they are possibly managed by non-specialists at private clinics. Recently, there have been significant advances in COPD management, and evidences of its appropriate pharmaceutical treatment are now available. Thus, there is a need for translational research with the recent advances in COPD management. This manuscript describes the concept of teamwork and inter- and intra-connection for better management of COPD patients.

Multicentre comparison of self-management in patients with COPD.

In patients with COPD, self-management plays an important role in disease management. Recently, self-management programmes have expanded patient education practices to include a variety of disease management techniques. We hypothesised that COPD patients have insufficient and/or different self-management needs according to institution. We compared information needs of patients between specialised clinics in Canada (SCC) and Japan and a hospital outpatient clinic in Japan (HCJ), all employing different self-management interventions. This cross-sectional study evaluated patients' information needs for disease management using the Lung Information Needs Questionnaire (LINQ). Furthermore, we assessed pulmonary function tests, modified Medical Research Council (mMRC) dyspnoea scale and frequencies of hospitalisations and emergency visits. The total number of patients was 183. Those attending SCC were younger (p=0.047), with lower forced expiratory volume in 1 s % predicted (p<0.0001), and scored higher on the mMRC dyspnoea scale. Total LINQ scores showed differences between institutions (p<0.0001). There was no difference for the smoking domain; however, SCC recorded significantly lower information needs for all other domains (p<0.02). No significant difference in emergency visits was seen between institutions, but HCJ recorded the highest rate of emergency visits, while SCC had significantly higher rates of hospitalisation (p=0.004). Differences were seen for frequency and duration of education between institutions. These results highlight the differences in information needs by institution and the importance of assessing individual needs. We believe, despite representing only one aspect of self-management, our findings reflect real-world circumstances, adding to the argument that self-management education should be structured, but flexible, to meet the changing needs of COPD patients.

Polymorphism of SERPINE2 gene is associated with pulmonary emphysema in consecutive autopsy cases.

BACKGROUND: The SERPINA1, SERPINA3, and SERPINE2 genes, which encode antiproteases, have been proposed to be susceptible genes for of chronic obstructive pulmonary disease (COPD) and related phenotypes. Whether they are associated with emphysema is not known. METHODS: Twelve previously reported single nucleotide polymorphisms (SNPs) in SERPINA1 (rs8004738, rs17751769, rs709932, rs11832, rs1303, rs28929474, and rs17580), SERPINA3 (rs4934, rs17473, and rs1800463), and SERPINE2 (rs840088 and rs975278) were genotyped in samples obtained from 1,335 consecutive autopsies of elderly Japanese people. The association between these SNPs and the severity of emphysema, as assessed using macroscopic scores, was determined. RESULTS: Emphysema of more than moderate degree was detected in 189 subjects (14.1%) and showed a significant gender difference (males, 20.5% and females, 7.0%; p < 0.0001). Among the 12 examined SNPs, only rs975278 in the SERPINE2 gene was positively associated with emphysema. Unlike the major alleles, homozygous minor alleles of rs975278 were associated with emphysema (odds ratio (OR) = 1.54; 95% confidence interval (CI) = 1.02-2.30; p = 0.037) and the association was very prominent in smokers (OR = 2.02; 95% CI = 1.29-3.15; p = 0.002). CONCLUSIONS: SERPINE2 may be a risk factor for the development of emphysema and its association with emphysema may be stronger in smokers.

Derivation and validation of a composite index of severity in chronic obstructive pulmonary disease: the DOSE Index.

RATIONALE: Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a multicomponent disease with systemic consequences and effects on quality of life. Single measures such as lung function provide a limited reflection of how the disease affects patients. Composite measures have the potential to account for many of the facets of COPD. OBJECTIVES: To derive and validate a multicomponent assessment tool of COPD severity that is applicable to all patients and health care settings. METHODS: The index was derived using data from 375 patients with COPD in primary care. Regression analysis led to a model explaining 48% of the variance in health status as measured by the Clinical COPD Questionnaire with four components: dyspnea (D), airflow obstruction (O), smoking status (S), and exacerbation frequency (E). The DOSE Index was validated in cross-sectional and longitudinal samples in various health care settings in Holland, Japan, and the United Kingdom. MEASUREMENTS AND MAIN RESULTS: The DOSE Index correlated with health status in all data sets. A high DOSE Index score (> or = 4) was associated with a greater risk of hospital admission (odds ratio, 8.3 [4.1-17]) or respiratory failure (odds ratio, 7.8 [3.4-18.3]). The index predicted exacerbations in the subsequent year (P < or = 0.014). CONCLUSIONS: The DOSE Index is a simple, valid tool for assessing the severity of COPD. The index is related to a range of clinically important outcomes such as health care consumption and predicts future events.