Observational studies assessing the pharmacological treatment of obstructive lung disease: strengths, challenges and considerations for study design

Improved medication adherence in COPD patients using tiotropium or tiotropium olodaterol with the HealthPrize digital behavior change program

OBJECTIVE

To assess the impact of the HealthPrize RespiPoints™ program on treatment adherence and persistence in adults with chronic obstructive pulmonary disease (COPD).

METHODS

In this retrospective cohort study, program participants and nonparticipants receiving tiotropium bromide (TIO) or TIO and olodaterol between 1 January 2015-31 March 2020 were propensity score matched (PSM), from the linked database of the HealthPrize patient list and IQVIA PharMetrics® Plus. Treatment adherence, persistence, healthcare resource utilization, and costs were compared. Multivariable logistic regression models assessed the odds of adherence (≥80% proportion of days covered [PDC]), adjusted risk of discontinuation, and adjusted total healthcare costs.

RESULTS

Program participants (n = 262) demonstrated a 44% greater adherence during followup than nonparticipants (n = 262) (mean [standard deviation] PDC: 0.72 [0.27] vs 0.50 [0.36], p < 0.0001). Participants had higher odds of adherence vs nonparticipants (adjusted odds ratio: 2.51; 95% confidence interval: 1.72-3.66, p < 0.0001) and a lower percentage of participants discontinued their index medication (19.85% vs 33.59%, p = 0.0004). Fewer participants were hospitalized during follow-up (13.74% vs 17.56%, p = 0.23); adjusted total medical costs were 24% lower (p = 0.08). Higher pharmacy costs partially offset lower healthcare costs.

CONCLUSIONS

Program participants showed improved COPD medication adherence and persistence compared to nonparticipants.

The utility of quantitative computed tomography in cohort studies of chronic obstructive pulmonary disease: a narrative review

Background and Objective

Chronic obstructive pulmonary disease (COPD) is a significant contributor to global morbidity and mortality. Quantitative computed tomography (QCT), a non-invasive imaging modality, offers the potential to assess lung structure and function in COPD patients. Amidst the coronavirus disease 2019 (COVID-19) pandemic, chest computed tomography (CT) scans have emerged as a viable alternative for assessing pulmonary function (e.g., spirometry), minimizing the risk of aerosolized virus transmission. However, the clinical application of QCT measurements is not yet widespread enough, necessitating broader validation to determine its usefulness in COPD management.

Methods

We conducted a search in the PubMed database in English from January 1, 2013 to April 20, 2023, using keywords and controlled vocabulary related to QCT, COPD, and cohort studies.

Key Content and Findings

Existing studies have demonstrated the potential of QCT in providing valuable information on lung volume, airway geometry, airway wall thickness, emphysema, and lung tissue density in COPD patients. Moreover, QCT values have shown robust correlations with pulmonary function tests, and can predict exacerbation risk and mortality in patients with COPD. QCT can even discern COPD subtypes based on phenotypic characteristics such as emphysema predominance, supporting targeted management and interventions.

Conclusions

QCT has shown promise in cohort studies related to COPD, since it can provide critical insights into the pathogenesis and progression of the disease. Further research is necessary to determine the clinical significance of QCT measurements for COPD management.

PREVALENCE AND IMPACT OF COMORBIDITIES IN INDIVIDUALS WITH COPD: A SYSTEMATIC REVIEW

This study aimed to describe the prevalence of comorbidities associated with chronic obstructive pulmonary disease (COPD) and their relation with relevant outcomes. A systematic review based on the PRISMA methodology was performed from January 2020 until July 2021. The MEDLINE, Lilacs, and Scielo databases were searched to identify studies related to COPD and its comorbidities. Observational studies on the prevalence of comorbidities in COPD patients and costs with health estimates, reduced quality of life, and mortality were included. Studies that were restricted to one or more COPD pain assessments and only specific comorbidities such as osteoporosis, bronchitis, and asthma were excluded. The initial search identified 1,409 studies and after applying the inclusion and exclusion criteria, 20 studies were finally selected for analysis (comprising data from 447,459 COPD subjects). The most frequent COPD comorbidities were: hypertension (range, 17%–64.7%), coronary artery disease (19.9%–47.8%), diabetes (10.2%–45%), osteoarthritis (18%–43.8%), psychiatric conditions (12.1%–33%), and asthma (14.7%–32.5%). Several comorbidities had an impact on the frequency and severity of COPD exacerbations, quality of life, and mortality risk, in particular malignancies, coronary artery disease, chronic heart failure, and cardiac arrhythmias. Comorbidities, especially cardiovascular diseases and diabetes, are frequent in COPD patients, and some of them are associated with higher mortality.

Heterogeneity within and between physician-diagnosed asthma and/or COPD: NOVELTY cohort

BACKGROUND

Studies of asthma and chronic obstructive pulmonary disease (COPD) typically focus on these diagnoses separately, limiting understanding of disease mechanisms and treatment options. NOVELTY is a global, 3-year, prospective observational study of patients with asthma and/or COPD from real-world clinical practice. We investigated heterogeneity and overlap by diagnosis and severity in this cohort.

METHODS

Patients with physician-assigned asthma, COPD or both (asthma+COPD) were enrolled, and stratified by diagnosis and severity. Baseline characteristics were reported descriptively by physician-assigned diagnosis and/or severity. Factors associated with physician-assessed severity were evaluated using ordinal logistic regression analysis.

RESULTS

Of 11 243 patients, 5940 (52.8%) had physician-assigned asthma, 1396 (12.4%) had asthma+COPD and 3907 (34.8%) had COPD; almost half were from primary care. Symptoms, health-related quality of life and spirometry showed substantial heterogeneity and overlap between asthma, asthma+COPD and COPD, with 23%, 62% and 64% of patients, respectively, having a ratio of post-bronchodilator forced expiratory volume in 1 s to forced vital capacity below the lower limit of normal. Symptoms and exacerbations increased with greater physician-assessed severity and were higher in asthma+COPD. However, 24.3% with mild asthma and 20.4% with mild COPD had experienced ≥1 exacerbation in the past 12 months. Medication records suggested both under-treatment and over-treatment relative to severity. Blood eosinophil counts varied little across diagnosis and severity groups, but blood neutrophil counts increased with severity across all diagnoses.

CONCLUSION

This analysis demonstrates marked heterogeneity within, and overlap between, physician-assigned diagnosis and severity groups in patients with asthma and/or COPD. Current diagnostic and severity classifications in clinical practice poorly differentiate between clinical phenotypes that may have specific risks and treatment implications.