Predictive factors for exacerbation and re-exacerbation in chronic obstructive pulmonary disease: an extension of the Cox model to analyze data from the Swiss COPD cohort

Respiratory Specialist Visits Before Admissions with COPD Exacerbation are Linked to Improved Management and Outcomes

Purpose

Exacerbations of COPD (ECOPD) significantly impact disease progression and mortality. Visiting a respiratory specialist (RS) in proximity to the exacerbation may lead to prompt treatment and improved outcomes. We aimed to evaluate the association between an RS visit 30-days before admission and exacerbation outcomes.

Patients and methods

The prospective study included subjects that were hospitalized with ECOPD between 2017 and 2019 in 13 medical centers. Pre-admission, in-hospital, and 30-day outcomes were assessed and compared between patients with and without a 30-day RS visit, using propensity score matching. A sub-group analysis was performed based on the reason for the RS visit (emergent vs regular follow-up).

Results

Three hundred and forty-four subjects were included, and 105 (31%) had pre-admission RS visit (RS group). Before matching, indicators of severe COPD were prevalent in the RS group, while after matching there were no differences. RS visits were associated with pre-hospital initiation of short acting bronchodilators (50% vs 36%), antibiotics (30% vs 17%), and systemic steroids (38% vs 22%). The RS group had longer duration between first symptoms to hospital arrival (median 5 vs 3 days, p < 0.01) and shorter hospital length-of-stay (median 4 vs 5 days, p = 0.04). In-hospital and 30-days outcomes were similar between the groups. However, a non-emergent pre-hospital RS visit was associated with improved in-hospital and 30-day outcomes.

Conclusion

Routine RS visits could lead to correct and early treatment for ECOPD with a potential for improved outcomes. These findings highlight the need for available specialists and higher awareness.

Clinical characteristics governing treatment adjustment in COPD patients: results from the Swiss COPD cohort study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a widespread chronic disease characterised by irreversible airway obstruction [1]. Features of clinical practice and healthcare systems for COPD patients can vary widely, even within similar healthcare structures. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy is considered the most reliable guidance for the management of COPD and aims to provide treating physicians with appropriate insight into the disease. COPD treatment adaptation typically mirrors the suggestions within the GOLD guidelines, depending on how the patient has been categorised. However, the present study posits that the reasons for adjusting COPD-related treatment are hugely varied.

OBJECTIVES

The objective of this study was to assess the clinical symptoms that govern both pharmacological and non-pharmacological treatment changes in COPD patients. Using this insight, the study offers suggestions for optimising COPD management through the implementation of GOLD guidelines.

METHODS

In this observational cohort study, 24 general practitioners screened 260 COPD patients for eligibility from 2015-2019. General practitioners were asked to collect general information from patients using a standardised questionnaire to document symptoms. During a follow-up visit, the patient's symptoms and changes in therapy were assessed and entered into a central electronic database. Sixty-five patients were removed from the analysis due to exclusion criteria, and 195 patients with at least one additional visit within one year of the baseline visit were included in the analysis. A change in therapy was defined as a change in either medication or non-medical treatment, such as pulmonary rehabilitation. Multivariable mixed models were used to identify associations between given symptoms and a step up in therapy, a step down, or a step up and a step down at the same time.

RESULTS

For the 195 patients included in analyses, a treatment adjustment was made during 28% of visits. In 49% of these adjustments, the change in therapy was a step up, in 33% a step down and in 18% a step up (an increase) of certain treatment factors and a step down (a reduction) of other prescribed treatments at the same time. In the multivariable analysis, we found that the severity of disease was linked to the probability of therapy adjustment: patients in GOLD Group C were more likely to experience an increase in therapy compared to patients in GOLD Group A (odds ratio [OR] 3.43 [95% confidence interval {CI}: 1.02-11.55; p = 0.135]). In addition, compared to patients with mild obstruction, patients with severe (OR 4.24 [95% CI: 1.88-9.56]) to very severe (OR 5.48 [95% CI: 1.31-22.96]) obstruction were more likely to experience a therapy increase (p <0.0001). Patients with comorbidities were less likely to experience a treatment increase than those without (OR 0.42 [95% CI: 0.24-0.73; p = 0.002]). A therapy decrease was associated with both a unit increase in COPD Assessment Test (CAT) score (OR 1.07 [95% CI: 1.01-1.14; p = 0.014]) and having experienced an exacerbation (OR 2.66 [95% CI: 1.01-6.97; p = 0.047]). The combination of steps up as well as steps down in therapy was predicted by exacerbation (OR 8.93 [95% CI: 1.16-68.28; p = 0.035]) and very severe obstruction (OR 589 [95% CI: 2.72 - >999; p = 0.109]).

CONCLUSIONS

This cohort study provides insight into the management of patients with COPD in a primary care setting. COPD Group C and airflow limitation GOLD 3-4 were both associated with an increase in COPD treatment. In patients with comorbidities, there were often no treatment changes. Exacerbations did not make therapy increases more probable. The presence of neither cough/sputum nor high CAT scores was associated with a step up in treatment.

Adherence to the GOLD Guidelines in Primary Care: Data from the Swiss COPD Cohort

(1) Introduction: Chronic obstructive pulmonary disease (COPD) and its associated morbidity and mortality are a global burden on both affected patients and healthcare systems. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) issues guidelines with the aim of improving COPD management. Previous studies reported significant variability in adherence to these recommendations. The objective of this study was to evaluate Swiss primary practitioners' adherence to the GOLD guidelines for the pharmacological treatment of stable COPD. (2) Methods: We studied patients who were included in the Swiss COPD cohort study, an ongoing prospective study in a primary care setting, between 2015 and 2022. The key inclusion criteria are age ≥ 40 years, FEV1/FVC ratio < 70%, and a smoking history of at least 20 pack-years. Adherence to the GOLD guidelines was assessed per visit and over time. (3) Results: The data of 225 COPD patients (mean age 67 ± 9 years, 64% male) and their respective 1163 visits were analyzed. In 65% of visits (726/1121), treatment was prescribed according to the GOLD guidelines. Non-adherence was most common in GOLD groups A and B (64% and 33%) and mainly consisted of over-treatment (two long-acting bronchodilators in group A (98/195, 50%) and ICS in groups A (21/195, 11%) and B (198/808, 25%)). In group D, the prescriptions conformed with the guidelines in 99% of cases (109/108). Guideline adherence was associated with high symptom load (COPD Assessment Test) (OR 1.04, p = 0.002), high number of exacerbations (OR = 2.07, p < 0.001), asthma overlap (OR 3.36, p = 0.049), and diabetes mellitus (OR 2.82, p = 0.045). (4) Conclusion: These results confirm a conflict between the GOLD recommendations and primary practice, mainly concerning over-treatment in GOLD groups A and B. Patients with high symptom load, high exacerbation risk, asthma overlap, and diabetes mellitus are more likely to be treated in conformity with the guidelines. Further research is needed to uncover the reasons for the discrepancies and to design strategies for improvement.

Predictors of Length of Stay, Mortality and Rehospitalization in COPD Patients: A Retrospective Cohort Study

Chronic obstructive pulmonary disease (COPD) is a highly prevalent chronic lung disease that has a significant impact on individuals and healthcare systems worldwide. This study aimed to identify factors that predict the length of a hospital stay (LOHS), one-year mortality, and rehospitalization within 6 months in patients admitted for acute exacerbation of COPD (AECOPD). A retrospective cohort study was conducted using data from 170 patients admitted to a district general hospital in Switzerland between January 2019 and February 2020. Sociodemographic and health-related variables measured at admission were analyzed as potential predictors. Multivariable zero-truncated negative binomial and logistic regression analyses were performed to assess the risk factors for LOHS (primary endpoint), mortality, and rehospitalization. The results show that an indication for oxygen supplementation was the only significant predictor of LOHS. In the logistic regression analysis, older age, COPD severity stages GOLD III and IV, active cancer and arrhythmias were associated with higher mortality, whereas rehabilitation after discharge was associated with lower mortality. There were no significant associations regarding rehospitalization. This study identified routinely available predictors for LOHS and mortality, which may further advance our understanding of AECOPD and thereby improve patient management, discharge planning, and hospital costs. The protective effect of rehabilitation after hospitalization regarding lower mortality warrants further confirmation and may improve the comprehensive management of patients with AECOPD.

Prognostic risk factors for moderate-to-severe exacerbations in patients with chronic obstructive pulmonary disease: a systematic literature review

Background

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. COPD exacerbations are associated with a worsening of lung function, increased disease burden, and mortality, and, therefore, preventing their occurrence is an important goal of COPD management. This review was conducted to identify the evidence base regarding risk factors and predictors of moderate-to-severe exacerbations in patients with COPD.

Methods

A literature review was performed in Embase, MEDLINE, MEDLINE In-Process, and the Cochrane Central Register of Controlled Trials (CENTRAL). Searches were conducted from January 2015 to July 2019. Eligible publications were peer-reviewed journal articles, published in English, that reported risk factors or predictors for the occurrence of moderate-to-severe exacerbations in adults age ≥ 40 years with a diagnosis of COPD.

Results

The literature review identified 5112 references, of which 113 publications (reporting results for 76 studies) met the eligibility criteria and were included in the review. Among the 76 studies included, 61 were observational and 15 were randomized controlled clinical trials. Exacerbation history was the strongest predictor of future exacerbations, with 34 studies reporting a significant association between history of exacerbations and risk of future moderate or severe exacerbations. Other significant risk factors identified in multiple studies included disease severity or bronchodilator reversibility (39 studies), comorbidities (34 studies), higher symptom burden (17 studies), and higher blood eosinophil count (16 studies).

Conclusions

This systematic literature review identified several demographic and clinical characteristics that predict the future risk of COPD exacerbations. Prior exacerbation history was confirmed as the most important predictor of future exacerbations. These prognostic factors may help clinicians identify patients at high risk of exacerbations, which are a major driver of the global burden of COPD, including morbidity and mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02123-5.

Association of COPD exacerbations and acute cardiovascular events: a systematic review and meta-analysis

Background:

The majority of patients with chronic obstructive pulmonary disease (COPD) suffer from comorbid cardiovascular (CV) disease. Accumulating evidence suggests a temporal association between COPD exacerbations and acute CV events, possibly due to lung hyperinflation, increased hypoxemia and systemic inflammation. The aims of the study were to estimate the risk of (1) acute CV events [acute myocardial infarction (AMI), CV-related death] or stroke in the months following a COPD exacerbation and (2) COPD exacerbation in the months following an acute CV event.

Methods:

A systematic literature review of observational studies published since 2000 was conducted by searching literature databases (Medline and Embase). Studies were eligible if conducted in adults with COPD, exposed to either COPD exacerbation or acute CV events, with outcomes of acute CV events or COPD exacerbation reported. Studies were appraised for relevance, bias and quality. Meta-analyses, using random-effect models, were performed for each outcome of interest, thus providing a pooled relative risk (RR) and its 95% confidence interval.

Results:

Eight studies were identified, of which seven were used for the meta-analyses examining the risk of CV events 1–3 months after an exacerbation compared with none. For stroke (six studies), RR was 1.68 (95% CI = 1.19–2.38). For AMI (six studies), RR was 2.43 (95% CI = 1.40–4.20). No studies exploring risk of exacerbation following an acute CV event were identified.

Conclusion:

This meta-analysis identified a markedly increased risk of stroke or AMI within a relatively short period of time following a COPD exacerbation. Although the underlying mechanisms are not fully elucidated, patients with COPD should be monitored for risk of CV outcomes after exacerbations. In addition, preventing exacerbations may decrease the risk of subsequent acute CV events.

Registration:

The study protocol was published via PROSPERO: International Prospective Register of Systematic Reviews (#CRD42020211055).

Prediction of Acute COPD Exacerbation in the Swiss Multicenter COPD Cohort Study (TOPDOCS) by Clinical Parameters, Medication Use, and Immunological Biomarkers

BACKGROUND AND OBJECTIVE

Whether immunological biomarkers combined with clinical characteristics measured during an exacerbation-free period are predictive of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) frequency and severity is unknown.

METHOD

We measured immunological biomarkers and clinical characteristics in 271 stable chronic obstructive pulmonary disease (COPD) patients (67% male, mean age 63 years) from "The Obstructive Pulmonary Disease Outcomes Cohort of Switzerland" cohort on a single occasion. One-year follow-up data were available for 178 patients. Variables independently associated with AECOPD frequency and severity were identified by multivariable regression analyses. Receiver operating characteristic analysis was used to obtain optimal cutoff levels and measure the area under the curve (AUC) in order to assess if baseline data can be used to predict future AECOPD.

RESULTS

Higher number of COPD medications (adjusted incident rate ratio [aIRR] 1.17) and platelet count (aIRR 1.03), and lower FEV1% predicted (aIRR 0.84) and IgG2 (aIRR 0.84) were independently associated with AECOPD frequency in the year before baseline. Optimal cutoff levels for experiencing frequent (>1) AECOPD were ≥3 COPD medications (AUC = 0.72), FEV1 ≤40% predicted (AUC = 0.72), and IgG2 ≤2.6 g/L (AUC = 0.64). The performance of a model using clinical and biomarker parameters to predict future, frequent AECOPD events in the same patients was fair (AUC = 0.78) but not superior to a model using only clinical parameters (AUC = 0.79). The IFN-lambda rs8099917GG-genotype was more prevalent in patients who had severe AECOPD.

CONCLUSIONS

Clinical and biomarker parameters assessed at a single point in time correlated with the frequency of AECOPD events during the year before and the year after assessment. However, only clinical parameters had fair discriminatory power in identifying patients likely to experience frequent AECOPD.

Treatment of COPD Groups GOLD A and B with Inhaled Corticosteroids in the COSYCONET Cohort - Determinants and Consequences

Background

In COPD patients of GOLD groups A and B, a high degree of treatment with inhaled corticosteroids (ICS) has been reported, which is regarded as overtreatment according to GOLD recommendations. We investigated which factors predict ICS use and which relationship it has to clinical and functional outcomes, or healthcare costs.

Methods

We used pooled data from visits 1 and 3 of the COSYCONET cohort (n=2741, n=2053, interval 1.5 years) including patients categorized as GOLD grades 1-4 and GOLD group A or B at both visits (n=1080). Comparisons were performed using ANOVA, and regression analyses using propensity matching and inverse probability weighting to adjust for differences between ICS groups. These were defined as having ICS at both visits (always) vs no ICS at both visits (never). Measures were divided into predictors of ICS treatment and outcomes.

Results

Among 1080 patients, 608 patients were eligible for ICS groups (n=297 never, n=311 always). Prior to matching, patients with ICS showed significantly (p<0.05 each) impaired lung function, symptoms and exacerbation history. After matching, the outcomes generic quality of life and CO diffusing capacity were increased in ICS patients (p<0.05 each). Moreover, costs for respiratory medication, but not total health care costs, were significantly elevated in the ICS group by 780€ per year.

Conclusion

ICS therapy in COPD GOLD A/B patients can have small positive and negative effects on clinical outcomes and health care costs, indicating that the clinical evaluation of ICS over-therapy in COPD requires a multi-dimensional approach.

A modelling framework for developing early warning systems of COPD emergency admissions

Chronic Obstructive Pulmonary Disease (COPD) is one of the leading causes of mortality worldwide and is a major contributor to the number of emergency admissions in the UK. We introduce a modelling framework for the development of early warning systems for COPD emergency admissions. We analyse the number of COPD emergency admissions using a Poisson generalised linear mixed model. We group risk factors into three main groups, namely pollution, weather and deprivation. We then carry out variable selection within each of the three domains of COPD risk. Based on a threshold of incidence rate, we then identify the model giving the highest sensitivity and specificity through the use of exceedance probabilities. The developed modelling framework provides a principled likelihood-based approach for detecting the exceedance of thresholds in COPD emergency admissions. Our results indicate that socio-economic risk factors are key to enhance the predictive power of the model.

Adherence to GOLD Recommendations among Swiss Pulmonologists and General Practitioners

Significant variability in adherence to COPD management recommendations has been reported. We aimed to evaluate real-life COPD pharmacotherapy prescribing patterns and adherence to the 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) global strategy in Switzerland. A questionnaire-based survey was conducted among Swiss general practitioners (GPs) and pulmonologists (PULs) from May 1 to November 30, 2017. Participants were invited to complete a questionnaire on their next 5-10 consecutive patients already receiving a pharmacological treatment for COPD. They were requested to assess dyspnea using the modified Medical Research Council (mMRC) dyspnea scale and to determine whether a treatment adjustment was indicated. Fifty-three PULs and 39 GPs completed questionnaires on 511 COPD patients. Dyspnea with mMRC grade ≥2 was reported in 62.5% of the patients, and 31.9% had had at least two exacerbations (or at least one with hospital admission) in the last 12 months. The vast majority (87.1%) of GOLD A patients were overtreated. In the GOLD B group, 52.2% of prescriptions were concordant with GOLD 2017 recommendations, but 37% of patients were overtreated. Among GOLD C patients, 49.2% received GOLD-adherent treatment and 47.5% were overtreated. In the GOLD D category, 78.8% of the patients received a treatment consistent with recommendations but 15.2% were undertreated. After reassessment of patient status, treatment was modified in 50.3% of the patients. This study confirms that discordance of real-world prescription patterns with international guidance is frequent. Further educational efforts are required to improve adherence to COPD management recommendations.

Pragmatic trial on inhaled corticosteroid withdrawal in patients with COPD in general practice

The therapeutic value of inhaled corticosteroids (ICSs) for COPD is limited. In published RCTs, ICS could be withdrawn in COPD patients without increasing exacerbation risk when bronchodilator treatment is optimized. Here we report on the feasibility and risks of ICS withdrawal in Dutch general practice for COPD patients without an indication for ICSs. In our pragmatic trial, general practitioners decided autonomously which of their COPD patients on ICS treatment could stop this, how this was done, and whether additional bronchodilator therapy was needed. We recruited 62 COPD patients (58 analysed) who were eligible for ICS withdrawal in 79 practices. In 32 patients (55.2%, 95% CI: 42.5–67.3%) ICS was withdrawn successfully, 19 (32.8%, 95% CI: 22.1–45.6%) restarted ICS treatment within six months, 12 patients (20.7%, 95% CI: 12.3–32.8%) had a moderate exacerbation, and one patient had a severe exacerbation. ICS withdrawal was successful in just over half of the patients with COPD without an indication for ICS.