FEV1 and FVC as robust risk factors for cardiovascular disease and mortality: Insights from a large population study.

INTRODUCTION: Data is limited on influence of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) in a large adult population, including individuals with normal spirometry at baseline. METHODS: Using the UK Biobank cohort, a multivariable Cox regression analysis was conducted on 406,424 individuals to examine the association between FEV1 and FVC, categorized into three groups based on their percentage of predicted values (%pred) (≥80, 60-80 and < 60), and overall mortality, cardiovascular mortality, myocardial infarction, stroke, and heart failure over approximately 12.5 years. Moreover, a subgroup analysis was conducted on 295,459 individuals who had normal spirometry. RESULTS: Reduced FEV1 and FVC %pred values were associated with an elevated risk across all studied outcomes. Individuals with the lowest FEV1 and FVC %pred values (<60 %) exhibited HR of 1.83 (95 % CI 1.74-1.93) and 1.98 (95 % CI 1.76-2.22) for overall mortality, and 1.96 (95 % CI 1.83-2.1) and 2.26 (95 % CI 1.94-2.63) for cardiovascular mortality. Moreover, a graded association was observed between lower FEV1 and FVC %pred, even among never smokers and individuals with normal spirometry at baseline. DISCUSSION: Reduced FEV1 and FVC represent robust risk factors for cardiovascular disease and mortality. The fact that the increased risk was evident also at FEV1 and FVC levels exceeding 80 %pred challenges the contemporary classification of lung function categories and the notion that the entire FEV1- and FVC-range above 80 % of predicted represents a normal lung function.

Biomarkers of chronic airflow limitation and COPD identified by mass spectrometry.

Rationale: COPD affects 300 million people worldwide and is the third leading cause of death according to World Health Organization global health estimates. Early symptoms are subtle, and so COPD is often diagnosed at an advanced stage. Thus, there is an unmet need for biomarkers that can identify individuals at early stages of the disease before clinical symptoms have manifested. To date, few biomarkers are available for clinical diagnostic use in COPD. Methods: We evaluated a panel of serum biomarkers related to inflammation and infection for their ability to discriminate between 77 subjects with chronic airflow limitation (CAL) and 142 subjects with COPD, versus 150 healthy subjects (divided into two control groups that were matched with regards to age, gender and smoking to CAL and COPD). Healthy subjects and CAL were from Burden of Obstructive Lung Disease (BOLD), a population-based study. CAL was defined by post-bronchodilatory forced expiratory volume in 1 s/forced vital capacity ratio <0.7 in the BOLD population. COPD subjects were from Tools for Identifying Exacerbations (TIE), a COPD patient cohort. Quantification of 100 biomarker candidates was done by liquid chromatography-tandem mass spectrometry. Results: Several protein-derived peptides were upregulated in CAL, compared to controls; most notably peptides representing histidine-rich glycoprotein (HRG), α1-acid glycoprotein (AGP1), α1-antitrypsin (α1AT) and fibronectin. Out of these, HRG-, AGP1- and α1AT-specific peptides were also elevated in the COPD cohort. Conclusion: HRG, AGP1 and α1AT biomarkers distinguish subjects with CAL and COPD from healthy controls. HRG and AGP1 represent novel findings.

Pharmacological treatment of asthma in Sweden from 2005 to 2015.

OBJECTIVE: Despite access to effective therapies many asthma patients still do not have well-controlled disease. This is possibly related to underuse of inhaled corticosteroids (ICS) and overuse of short-acting ß2-agonists (SABA). Our aim was to investigate longitudinal trends and associated factors in asthma treatment. METHODS: Two separate cohorts of adults with physician-diagnosed asthma were randomly selected from 14 hospitals and 56 primary health centers in Sweden in 2005 (n = 1182) and 2015 (n = 1225). Information about symptoms, maintenance treatment, and use of rescue medication was collected by questionnaires. Associations between treatment and sex, age, smoking, education, body mass index (BMI), physical activity, allergic asthma, and symptom control were analyzed using Pearson's chi2-test. Odds ratios (ORs) were calculated using logistic regression. RESULTS: Maintenance treatment with ICS together with long-acting ß2-agonists (LABA) and/or montelukast increased from 39.2% to 44.2% (p = 0.012). The use of ICS + LABA as-needed increased (11.1-18.9%, p < 0.001), while SABA use decreased (46.4- 41.8%, p = 0.023). Regular treatment with ICS did not change notably (54.2-57.2%, p = 0.14). Older age, former smoking, and poor symptom control were related to treatment with ICS + LABA/montelukast. In 2015, 22.7% reported daily use of SABA. A higher step of maintenance treatment, older age, obesity, shorter education, current smoking, allergic asthma, low or very high physical activity, and a history of exacerbations were associated with daily SABA use. CONCLUSIONS: The use of ICS + LABA both for maintenance treatment and symptom relief has increased over time. Despite this, the problem of low use of ICS and high use of SABA remains.

Diagnostic spirometry in COPD is increasing, a comparison of two Swedish cohorts.

Spirometry should be used to confirm a diagnosis of chronic obstructive pulmonary disease (COPD). This test is not always performed, leading to possible misdiagnosis. We investigated whether the proportion of patients with diagnostic spirometry has increased over time as well as factors associated with omitted or incorrectly interpreted spirometry. Data from medical reviews and a questionnaire from primary and secondary care patients with a doctors' diagnosis of COPD between 2004 and 2010 were collected. Data were compared with a COPD cohort diagnosed between 2000 and 2003. Among 703 patients with a first diagnosis of COPD between 2004 and 2010, 88% had a diagnostic spirometry, compared with 59% (p < 0.001) in the previous cohort. Factors associated with not having diagnostic spirometry were current smoking (OR 2.21; 95% CI 1.36-3.60), low educational level (OR 1.81; 1.09-3.02) and management in primary care (OR 2.28; 1.02-5.14). The correct interpretation of spirometry results increased (75% vs 82%; p = 0.010). Among patients with a repeated spirometry, 94% had a persistent FEV1/FVC or FEV1/VC ratio <0.70.

Factors Associated with the Non-Exacerbator Phenotype of Chronic Obstructive Pulmonary Disease.

Background: Patients with chronic obstructive pulmonary disease (COPD) and no exacerbations may need less maintenance treatment and follow-up. The aim was to identify factors associated with a non-exacerbator COPD phenotype. Methods: Cross-sectional analysis of 1354 patients from primary and secondary care, with a doctor's diagnosis of COPD. In 2014, data on demographics, exacerbation frequency and symptoms using COPD Assessment Test (CAT) were collected using questionnaires and on spirometry and comorbid conditions by record review. The non-exacerbator phenotype was defined as having reported no exacerbations the previous six months. Multivariable logistic regression with the non-exacerbator phenotype as dependent variable was performed, including stratification and interaction analyses by sex. Results: The non-exacerbator phenotype was found in 891 (66%) patients and was independently associated with COPD stage 1 (OR [95% CI] 5.72 [3.30-9.92]), stage 2 (3.42 [2.13-5.51]) and stage 3 (2.38 [1.46-3.88]) compared with stage 4, and with CAT score <10 (3.35 [2.34-4.80]). Chronic bronchitis and underweight were inversely associated with the non-exacerbator phenotype (0.47 [0.28-0.79]) and (0.68 [0.48-0.97]), respectively. The proportion of non-exacerbators was higher among patients with no maintenance treatment or a single bronchodilator. The association of COPD stage 1 compared with stage 4 with the non-exacerbator phenotype was stronger in men (p for interaction 0.048). In women, underweight and obesity were both inversely associated with the non-exacerbator phenotype (p for interaction 0.033 and 0.046 respectively), and in men heart failure was inversely associated with the non-exacerbator phenotype (p for interaction 0.030). Conclusion: The non-exacerbator phenotype is common, especially in patients with no maintenance treatment or a single bronchodilator, and is characterized by preserved lung function, low symptom burden, and by absence of chronic bronchitis, underweight and obesity and heart failure. We suggest these patients may need less treatment and follow-up, but that management of comorbid conditions is important to avoid exacerbations.

Cardiovascular disease-linked plasma proteins are mainly associated with lung volume.

Background: Epidemiological studies have shown that impaired lung function is common and associated with increased risk of cardiovascular disease. Increased levels of several inflammatory and cardiovascular disease-related plasma proteins have been associated with impaired lung function. The aim was to study the association between plasma proteomics and forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC ratio. Methods: We used a discovery and replication approach in two community-based cohorts, EpiHealth and the Malmö Offspring Study (total n=2874), to cross-sectionally study 242 cardiovascular disease- and metabolism-linked proteins in relation to FEV1, FVC (both % predicted) and FEV1/FVC ratio. A false discovery rate of 5% was used as the significance threshold in the discovery cohort. Results: Plasma fatty acid-binding protein 4, interleukin-1 receptor antagonist, interleukin-6 and leptin were negatively associated with FEV1 and paraoxonase 3 was positively associated therewith. Fatty acid-binding protein 4, fibroblast growth factor 21, interleukin-1 receptor antagonist, interleukin-6 and leptin were negatively associated with FVC and agouti-related protein, insulin-like growth factor-binding protein 2, paraoxonase 3 and receptor for advanced glycation end products were positively associated therewith. No proteins were associated with FEV1/FVC ratio. A sensitivity analysis in EpiHealth revealed only minor changes after excluding individuals with known cardiovascular disease, diabetes or obesity. Conclusions: Five proteins were associated with both FEV1 and FVC. Four proteins associated with only FVC and none with FEV1/FVC ratio, suggesting associations mainly through lung volume, not airway obstruction. However, additional studies are needed to investigate underlying mechanisms for these findings.

Comorbid Heart Disease in Patients with COPD is Associated with Increased Hospitalization and Mortality - A 15-Year Follow-Up.

Purpose: The aim of this study was to examine the association of comorbid heart disease, defined as chronic heart failure or ischemic heart disease, on all-cause and cause-specific hospitalization and mortality in patients with COPD over a period of nearly 15 years. Materials and Methods: The cohort study included patients with COPD from primary and secondary care in 2005 with data from questionnaires and medical record reviews. The Swedish Board of Health and Welfare provided hospitalization and mortality data from 2005 through 2019. Cox regression analyses, adjusted for sex, age, educational level, smoking status, BMI, exacerbations, dyspnea score and comorbid diabetes or hypertension, assessed the association of comorbid heart disease with all-cause and cause-specific time to first hospitalization and death. Linear regression analyses, adjusted for the same variables, assessed this association with hospitalization days per year for those patients that had been hospitalized. Results: Of the 1071 patients, 262 (25%) had heart disease at baseline. Cox regression analysis showed a higher risk of hospitalization for patients with heart disease for all-cause (HR (95% CI) 1.55; 1.32-1.82), cardiovascular (2.14; 1.70-2.70) and other causes (1.27; 1.06-1.52). Patients with heart disease also had an increased risk of all-cause (1.77; 1.48-2.12), cardiovascular (3.40; 2.41-4.78) and other (1.50; 1.09-2.06) mortality. Heart disease was significantly associated with more hospitalization days per year of all-cause (regression coefficient 0.37; 95% CI 0.15-0.59), cardiovascular (0.57; 0.27-0.86) and other (0.37; 0.12-0.62) causes. No significant associations were found between heart disease and respiratory causes of hospitalization and death. Conclusion: Comorbid heart disease in patients with COPD is associated with an increased risk for all-cause hospitalization and mortality, mainly due to an increase of hospitalization and death of cardiovascular and other causes, but not because of respiratory disease. This finding advocates the need of a strong clinical focus on primary and secondary prevention of cardiovascular disease in patients with COPD.

Does multimorbidity result in de-prioritisation of COPD in primary care?

The aim of this study was to describe factors associated with having COPD regularly reviewed in primary care by a nurse or physician and assess whether there was de-prioritisation for COPD in multimorbid patients. We defined de-prioritisation as not having at least one check-up by a physician during a two-year period. Among 713 COPD patients in the Swedish PRAXIS study, 473 (66%) had at least one check-up during the study period (ending in 2014). Patients with check-ups were more likely to have three or more comorbid conditions (31.9% vs. 24.6%) and exacerbations (35.1% vs. 21.7%) than those without. Compared with those without comorbidity, those with three or more diagnoses had increased relative risk ratios (and 95% CI) for consultations discussing COPD with only a physician (5.63 (2.68-11.79)), COPD-nurse only (1.67 (0.83-3.37)) or both (2.11 (1.09-4.06)). COPD patients received more frequent check-ups considering COPD if they had comorbidity or a history of exacerbations. We found no evidence of de-prioritisation for COPD in multimorbid patients.

Alveolar Nitric Oxide in Chronic Obstructive Pulmonary Disease-A Two-Year Follow-Up.

Chronic obstructive pulmonary disease (COPD) affects the airways and gas exchange areas. Nitric oxide (NO) production from the airways is presented as FENO50 and from the gas exchange areas as alveolar NO (CANO). We aimed to evaluate, over two years, the consistency of the CANO estimations in subjects with COPD. A total of 110 subjects (45 men) who completed the study were included from primary and secondary care settings. CANO was estimated using the two-compartment model. CANO increased slightly during the two-year follow-up (p = 0.01), but FENO50 remained unchanged (p = 0.24). Among the subjects with a low CANO (<1 ppb) at inclusion, only 2% remained at a low level. For those at a high level (>2 ppb), 29% remained so. The modified Medical Research Council dyspnoea scale (mMRC) score increased at least one point in 29% of the subjects, and those subjects also increased in CANO from 0.9 (0.5, 2.1) ppb to 1.8 (1.1, 2.3) ppb, p = 0.015. We conclude that alveolar NO increased slightly over two years, together with a small decline in lung function. The increase in CANO was found especially in those whose levels of dyspnoea increased over time.

One additional educational session in inhaler use to patients with COPD in primary health care - A controlled clinical trial.

OBJECTIVE: To investigate whether one additional educational session about inhaler use, delivered to patients with COPD in primary healthcare, could affect the patients' skills in inhaler use. Specifically, to study the effects on errors related to handling the device, to inhalation technique, and to both. METHODS: This nonrandomized controlled clinical trial included 64 patients who used devices and made errors. COPD nurses assessed inhaler use using a checklist and educated patients. Intervention group received one additional educational session after two weeks. RESULTS: At baseline, patients in the IG had more devices (n = 2,1) compared to patients in the CG (n = 1,6) (p = 0.003). No other statistically significant differences were seen at baseline. At follow-up, intervention group showed a lower proportion of patients who made errors related to handling the device (p = 0.006). No differences were seen in the other categories. CONCLUSION: One additional educational session in inhaler use for patients with COPD was effective in reducing the proportion of patients making errors related to handling of their devices. PRACTICE IMPLICATIONS: Categorization of errors might help healthcare professionals to assess the suitability of patients' devices, tailor patient education, and thus improve patient health.

Treatment Patterns, Socioeconomic Status and Clinical Burden in Mild COPD: A Swedish Real-World, Retrospective Cohort Study, the ARCTIC Study.

Background: Patients with mild chronic obstructive pulmonary disease (COPD) account for more than half of the total COPD population but are often undiagnosed and sparsely studied. This real-world, longitudinal study compared the socioeconomic burden, clinical characteristics and treatment patterns in patients with mild COPD and age- and gender-matched controls. Patients and methods: Our population included mild COPD patients (forced expiratory volume in one second ≥80% of predicted value) and reference controls from 52 Swedish primary care centres over 15 years (2000-2014). We linked electronic medical record (EMR) data to Sweden's National Health Registries. The outcomes analyzed were socioeconomic status including annual income from work, presence of comorbidities and the use of medications. Results: 844 patients with mild COPD were included in this study and matched with 844 reference controls. Compared with the reference controls, mild COPD patients had a significantly lower annual income from work (mean difference, men: 12,559€ and women: 7143€) and were significantly less likely to be married or employed. The presence of comorbidities, including cardiovascular disease, anxiety and depression (only women) was significantly higher in mild COPD patients. The use of medications, such as proton pump inhibitors, antidepressants, central painkillers and sleep medications, was significantly higher in the mild COPD group. Conclusion: Mild COPD presents a considerable socioeconomic and clinical burden compared with reference controls The findings suggest that COPD constitutes a condition that influences health status even in mild disease clearly demanding an increased need for early detection and treatment.

MAIT cell counts are associated with the risk of hospitalization in COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation associated with chronic inflammation in the airways. Mucosal-associated invariant T (MAIT) cells are unconventional, innate-like T cells highly abundant in mucosal tissues including the lung. We hypothesized that the characteristics of MAIT cells in circulation may be prospectively associated with COPD morbidity. METHODS: COPD subjects (n = 61) from the Tools for Identifying Exacerbations (TIE) study were recruited when in stable condition. At study entry, forced expiratory volume in 1 s (FEV1) was measured and peripheral blood mononuclear cells were cryopreserved for later analysis by flow cytometry. Patients were followed for 3 years to record clinically meaningful outcomes. RESULTS: Patients who required hospitalization at one or more occasions during the 3-year follow-up (n = 21) had lower MAIT cell counts in peripheral blood at study inclusion, compared with patients who did not get hospitalized (p = 0.036). In contrast, hospitalized and never hospitalized patients did not differ in CD8 or CD4 T cell counts (p = 0.482 and p = 0.221, respectively). Moreover, MAIT cells in hospitalized subjects showed a more activated phenotype with higher CD38 expression (p = 0.014), and there was a trend towards higher LAG-3 expression (p = 0.052). Conventional CD4 and CD8 T cells were similar between the groups. Next we performed multi-variable logistic regression analysis with hospitalizations as dependent variable, and FEV1, GOLD 2017 group, and quantity or activation of MAIT and conventional T cells as independent variables. MAIT cell count, CD38 expression on MAIT cells, and LAG-3 expression on both MAIT and CD8 T cells were all independently associated with the risk of hospitalization. CONCLUSIONS: These findings suggest that MAIT cells might reflect a novel, FEV1-independent immunological dimension in the complexity of COPD. The potential implication of MAIT cells in COPD pathogenesis and MAIT cells' prognostic potential deserve further investigation.

Changes in critical inhaler technique errors in inhaled COPD treatment - A one-year follow-up study in Sweden.

BACKGROUND: Critical inhaler technique errors have been associated with lower treatment efficacy in chronic obstructive pulmonary disease (COPD). We aimed to assess and follow-up critical inhaler technique errors, and to investigate their association with COPD symptoms and exacerbations. METHODS: COPD-diagnosed primary and secondary care outpatients (n = 310) demonstrated inhaler technique with inhaler devices they were currently using. Critical errors in opening, positioning and loading the inhaler device, and exhalation through dry-powder inhalers were assessed and corrected, and the assessment was repeated one year later. COPD Assessment Test, the modified Medical Research Council dyspnoea scale and history of exacerbations were collected at both visits. RESULTS: The proportion of patients making ≥1 critical inhaler technique error was lower at follow-up in the total population (46% vs 37%, p = 0.01) and among patients with unchanged device models (46% vs 35%, p = 0.02), but not among patients with a new inhaler device model (46% vs 41%, p = 0.56). Not positioning the device correctly was the most common critical error at both visits (30% and 22%). Seventy-four percent of the patients had unchanged COPD treatment from baseline to follow-up. Treatment escalation, de-escalation, and switch was observed in 14%, 11%, and 1% of the patients, respectively. No association was found between critical errors and COPD symptoms or exacerbations. CONCLUSIONS: Assessment and correction of inhaler technique was associated with a decrease in critical inhaler technique errors. This effect was most pronounced in patients using the same device models throughout the follow-up period.

Prioritising primary care respiratory research needs: results from the 2020 International Primary Care Respiratory Group (IPCRG) global e-Delphi exercise.

Respiratory diseases remain a significant cause of global morbidity and mortality and primary care plays a central role in their prevention, diagnosis and management. An e-Delphi process was employed to identify and prioritise the current respiratory research needs of primary care health professionals worldwide. One hundred and twelve community-based physicians, nurses and other healthcare professionals from 27 high-, middle- and low-income countries suggested 608 initial research questions, reduced after evidence review by 27 academic experts to 176 questions covering diagnosis, management, monitoring, self-management and prognosis of asthma, COPD and other respiratory conditions (including infections, lung cancer, tobacco control, sleep apnoea). Forty-nine questions reached 80% consensus for importance. Cross-cutting themes identified were: a need for more effective training of primary care clinicians; evidence and guidelines specifically relevant to primary care, adaption for local and low-resource settings; empowerment of patients to improve self-management; and the role of the multidisciplinary healthcare team.

Factors associated with self-assessed asthma severity.

BACKGROUND: Asthma severity can be estimated as the level of medication needed to achieve asthma control or by the patient's subjective assessment. Factors associated with self-assessed asthma severity are still incompletely explored. AIM: The aim was to study factors associated with self-assessed moderate or severe asthma. METHOD: In total, 1828 randomly selected asthma patients from primary (69%) and secondary (31%) care, completed a questionnaire including items about patient characteristics, comorbidity, the Asthma Control Test (ACT), emergency care visits and a scale for self-assessed asthma severity. Logistic regression was used to analyze associations with the dependent variable, self-assessed moderate or severe asthma in the entire study population and stratified by sex. RESULTS: Of the patients, 883 (45%) reported having moderate or severe asthma. Factors independently associated with self-assessed moderate or severe asthma were age >60 years (OR [95% CI] 1.98 [1.37-2.85]), allergic rhino-conjunctivitis (1.43 [1.05-1.95]), sinusitis (1.45 [1.09-1.93]), poor asthma control as measured by ACT <20 (5.64 [4.45-7.16]) and emergency care visits the previous year (2.52 [1.90-3.34]). Lower level of education was associated with self-assessed moderate/severe asthma in women (1.16 [1.05-2.43]) but not in men (0.90 [0.65-1.25]), p for interaction = .012. CONCLUSION: Poor asthma control, allergic rhino-conjunctivitis, recent sinusitis and older age were independently associated with self-assessed moderate or severe asthma. Important implications are that comorbid conditions of the upper airways should always be considered as part of asthma management, and that elderly patients may need extra attention.

Quality of life and asthma control related to hormonal transitions in women's lives.

OBJECTIVES: The aim was to investigate if menstruation and use of exogenous sex hormones influence self-reported asthma related quality of life (QoL) and asthma control. METHODS: The study is based on two asthma cohorts randomly selected in primary and secondary care. A total of 622 female patients 18-65 years were included and classified as premenopausal ≤ 46 years (n = 338) and peri/postmenopausal 47-65 years (n = 284). Questionnaire data from 2012 and 2014 with demographics, asthma related issues and sex hormone status. Outcome measures were Mini Asthma Quality of Life Questionnaire (Mini-AQLQ) and asthma control including Asthma Control Test (ACT) and exacerbations last six months. RESULTS: Premenopausal women with menstruation related asthma worsening, perimenstrual asthma (PMA) (9%), had a clinically relevant lower Mini-AQLQ mean score 4.9 vs. 5.8 (p < 0.001), lower asthma control with ACT score < 20, 72% vs. 28% (p < 0.001) and higher exacerbation frequency 44% vs. 20% (p = 0.004) compared with women without PMA. Women with irregular menstruation had higher exacerbation frequency than women with regular menstruation (p = 0.023). Hormonal contraceptives had no impact on QoL and asthma control. Peri/postmenopausal women with menopausal hormone therapy (MHT) had a clinically relevant lower Mini-AQLQ mean score compared to those without MHT, 4.9 vs 5.4 (p < 0.001), but no differences in asthma control. CONCLUSION: Women with PMA had lower QoL and more uncontrolled asthma than women without PMA. Peri/postmenopausal women with MHT had lower QoL than women without MHT. Individual clinical management of women with asthma may benefit from information about their sex hormone status.

Developing a short-term prediction model for asthma exacerbations from Swedish primary care patients' data using machine learning - Based on the ARCTIC study.

OBJECTIVE: The ability to predict impending asthma exacerbations may allow better utilization of healthcare resources, prevention of hospitalization and improve patient outcomes. We aimed to develop models using machine learning to predict risk of exacerbations. METHODS: Data from 29,396 asthma patients was collected from electronic medical records and national registers covering clinical and epidemiological factors (e.g. comorbidities, health care contacts), between 2000 and 2013. Machine-learning classifiers were used to create models to predict exacerbations within the next 15 days. Model selection was done using the mean cross validation score of area under precision-recall curve (AUPRC). RESULTS: The most important predictors of exacerbation were comorbidity burden and previous exacerbations. Model validation on test data yielded an AUPRC = 0.007 (95% CI: ± 0.0002), indicating that historic clinical information alone may not be sufficient to predict a near future risk of asthma exacerbation. CONCLUSIONS: Supplementation with additional data on environmental triggers, (e.g. weather, pollen count, air quality) and from wearables, might be necessary to improve performance of the short-term predictive model to develop a more clinically useful tool.

The Impact of Exacerbation Frequency on Clinical and Economic Outcomes in Swedish COPD Patients: The ARCTIC Study.

PURPOSE: The aim of this study was to assess the association between exacerbation frequency and clinical and economic outcomes in patients with COPD. PATIENTS AND METHODS: Electronic medical record data linked to National Health Registries were collected from COPD patients at 52 Swedish primary care centers (2000-2014). The outcomes analyzed were exacerbation rate, mortality, COPD treatments, lung function and healthcare costs during the follow-up period. Based on the exacerbation rate two years before index date, the patients were initially classified into three groups, either 0, 1 or ≥2 exacerbations per year. After the index date, the classification into exacerbation groups was updated each year based on the exacerbation rate during the last year of follow-up. A sensitivity analysis was conducted excluding patients with asthma diagnosis from the analysis. RESULTS: In total 18,586 COPD patients were analyzed. A majority of the patients (60-70%) who either have had no exacerbation or frequent exacerbations (≥2/year) during the pre-index period remained in their group (ie, with 0 or ≥2 annual exacerbations) during up to 11 years of follow-up. Compared with having no exacerbation, mortality was higher in patients having 1 (HR; 2.06 [1.93-2.20]) and ≥2 (4.58 [4.33-4.84]) exacerbations at any time during the follow-up. Lung function decline was more rapid in patients with frequent exacerbations and there was an almost linear relationship between exacerbations frequency and mortality. Total healthcare costs were higher in the frequent exacerbation group (≥2/year) than in patients with no or one exacerbation annually (p<0.0001 for both). The results did not differ from the main analysis after exclusion of patients with a concurrent asthma diagnosis. CONCLUSION: In addition to faster lung function decline and increased mortality, frequent exacerbations in COPD patients imply a significant economic burden.

Prediction of Mortality Using Different COPD Risk Assessments - A 12-Year Follow-Up.

PURPOSE: A multidimensional approach in the risk assessment of chronic obstructive pulmonary disease (COPD) is preferable. The aim of this study is to compare the prognostic ability for mortality by different COPD assessment systems; spirometric staging, classification by GOLD 2011, GOLD 2017, the age, dyspnea, obstruction (ADO) and the dyspnea, obstruction, smoking, exacerbation (DOSE) indices. PATIENTS AND METHODS: A total of 490 patients diagnosed with COPD were recruited from primary and secondary care in central Sweden in 2005. The cohort was followed until 2017. Data for categorization using the different assessment systems were obtained through questionnaire data from 2005 and medical record reviews between 2000 and 2003. Kaplan-Meier survival analyses and Cox proportional hazard models were used to assess mortality risk. Receiver operating characteristic curves estimated areas under the curve (AUC) to evaluate each assessment systems´ ability to predict mortality. RESULTS: By the end of follow-up, 49% of the patients were deceased. The mortality rate was higher for patients categorized as stage 3-4, GOLD D in both GOLD classifications and those with a DOSE score above 4 and ADO score above 8. The ADO index was most accurate for predicting mortality, AUC 0.79 (95% CI 0.75-0.83) for all-cause mortality and 0.80 (95% CI 0.75-0.85) for respiratory mortality. The AUC values for stages 1-4, GOLD 2011, GOLD 2017 and DOSE index were 0.73, 0.66, 0.63 and 0.69, respectively, for all-cause mortality. CONCLUSION: All of the risk assessment systems predict mortality. The ADO index was in this study the best predictor and could be a helpful tool in COPD risk assessment.

Predicting Hospitalization Due to COPD Exacerbations in Swedish Primary Care Patients Using Machine Learning - Based on the ARCTIC Study.

PURPOSE: Chronic obstructive pulmonary disease (COPD) exacerbations can negatively impact disease severity, progression, mortality and lead to hospitalizations. We aimed to develop a model that predicts a patient's risk of hospitalization due to severe exacerbations (defined as COPD-related hospitalizations) of COPD, using Swedish patient level data. PATIENTS AND METHODS: Patient level data for 7823 Swedish patients with COPD was collected from electronic medical records (EMRs) and national registries covering healthcare contacts, diagnoses, prescriptions, lab tests, hospitalizations and socioeconomic factors between 2000 and 2013. Models were created using machine-learning methods to predict risk of imminent exacerbation causing patient hospitalization due to COPD within the next 10 days. Exacerbations occurring within this period were considered as one event. Model performance was assessed using the Area under the Precision-Recall Curve (AUPRC). To compare performance with previous similar studies, the Area Under Receiver Operating Curve (AUROC) was also reported. The model with the highest mean cross validation AUPRC was selected as the final model and was in a final step trained on the entire training dataset. RESULTS: The most important factors for predicting severe exacerbations were exacerbations in the previous six months and in whole history, number of COPD-related healthcare contacts and comorbidity burden. Validation on test data yielded an AUROC of 0.86 and AUPRC of 0.08, which was high in comparison to previously published attempts to predict COPD exacerbation. CONCLUSION: Our work suggests that clinically available information on patient history collected via automated retrieval from EMRs and national registries or directly during patient consultation can form the basis for future clinical tools to predict risk of severe COPD exacerbations.