Methods to assess COPD medications adherence in healthcare databases: a systematic review

Medication adherence to inhalation therapy and the risk of COPD exacerbations: a systematic review with meta-analysis

BACKGROUND

Assessing medication adherence is crucial in chronic obstructive pulmonary disease (COPD) management to prevent exacerbations. However, it is unclear whether this association between adherence and exacerbations is influenced by the adherence assessment methods or thresholds used. Electronic healthcare databases are valuable to study exacerbations and adherence in real life. We aimed to systematically review the literature to identify adherence assessment methods and thresholds used in healthcare databases when investigating the association between medication adherence and COPD exacerbations and to meta-analyse the associated effect sizes.

METHOD

MEDLINE, Web of Science and Embase were searched for peer-reviewed articles, written in English, published up to 10 October 2022 (PROSPERO: CRD42022363449). Two reviewers independently conducted screening for inclusion and performed data extraction. A qualitative approach described the adherence assessment methods and thresholds used. A quantitative approach (meta-analysis using random effects model) estimated the association between adherence and the risk of COPD exacerbations.

RESULTS

Eight studies were included in the systematic review of which five studies were included in the meta-analysis. The medication possession ratio (MPR) and the proportion of days covered (PDC) were the adherence assessment methods used and 0.80 was always used as threshold to differentiate good from poor adherence. Adherence and exacerbations were mostly measured over the same time period. Poor adherence (MPR or PDC<0.80) was significantly associated with a higher COPD exacerbation risk (OR 1.40, 95% CI 1.21 to 1.62, I2=85%), regardless of the adherence assessment method used. Results were consistent when stratified by exacerbation severity. Poor adherence was also associated with a time-dependent risk of COPD exacerbations (incidence rate ratio 1.31, 95% CI 1.17 to 1.46).

CONCLUSION

Our systematic review with meta-analysis demonstrated a 40% increased risk of COPD exacerbations in case of poor adherence to inhaler medication.

PROSPERO REGISTRATION NUMBER

CRD42022363449.

Non-adherence to COPD medications and its association with adverse events: A longitudinal population based cohort study of older adults

OBJECTIVE

To determine the association between non-adherence to long term chronic obstructive pulmonary disease (COPD) medications and COPD related emergency department (ED) visits and hospitalizations in patients with incident COPD, utilizing time varying measures of adherence as well as accounting for time-varying confounding impacted by prior adherence.

STUDY DESIGN AND SETTING

We conducted a population-based retrospective cohort study between 2007-2017 among individuals aged 66 years and older with incident COPD using multiple linked administrative health databases from the province of Ontario, Canada. Adherence to COPD medications was measured using time varying proportion of days covered based on insurance claims for medications dispensed at community pharmacies. The parametric g-formula was used to assess the association between time-varying adherence (in the last 90-days) to COPD medications and risk of COPD related hospitalizations and ED visits while accounting for time varying confounding by COPD severity.

RESULTS

Overall, 60,251 individuals with incident COPD were included; mean age was 76 (SD 7) and 59% were male. Mean adherence over the entire follow-up was 23% (SD 0.3). There were 7248 (12%) COPD related ED visits (2.8 events per 100 person years [PY]) and 9188 (15%) COPD related hospitalizations (3.5 events per 100 PY). Compared to those with 0% 90-day adherence, those with adherence between 1-33% had a 19% decreased risk of COPD related ED visits (adjusted risk ratio[aRR]:0.81, 95% confidence interval [CI]:0.78-0.83), those with adherence between 34%-67% had a 18% decreased risk (aRR: 0.82, 95% CI: 0.77-0.85) while those with 68%-100% 90-day adherence had a 63% increased risk of COPD related ED visits (aRR: 1.63, 95% CI: 1.47-1.78). Nearly identical results were obtained for COPD specific hospitalizations.

CONCLUSION

After accounting for time varying confounding by COPD severity, the highest time varying 90-days adherence was associated with an increased risk of both COPD related ED visits and hospitalizations compared to the lowest adherence categories. Differences in COPD severity between adherence categories, perception of need for medication management in the higher adherence categories, and potential residual confounding makes it difficult to disentangle the independent effects of adherence from the severity of the condition itself.

Potential marker genes for chronic obstructive pulmonary disease revealed based on single-cell sequencing and Mendelian randomization analysis

BACKGROUND

Progress is being made in the prevention and treatment of chronic obstructive pulmonary disease (COPD), but it is still unsatisfactory. With the development of genetic technology, validated genetic information can better explain COPD.

OBJECTIVE

The study utilized scRNA-seq and Mendelian randomization analysis of eQTLs to identify crucial genes and potential mechanistic pathways underlying COPD pathogenesis.

MEHODS

Single-cell sequencing data were used to identify marker genes for immune cells in the COPD process. Data on eQTLs for immune cell marker genes were obtained from the eQTLGen consortium. To estimate the causal effect of marker genes on COPD, we selected an independent cohort (ukb-b-16751) derived from the UK Biobank database for two-sample Mendelian randomization analysis. Subsequently, we performed immune infiltration analysis, gene set enrichment analysis (GSEA), and co-expression network analysis on the key genes.

RESULTS

The 154 immune cell-associated marker genes identified were mainly involved in pathways such as vacuolar cleavage, positive regulation of immune response and regulation of cell activation. Mendelian randomization analysis screened four pairs of marker genes (GZMH, COTL1, CSTA and CD14) were causally associated with COPD. These four key genes were significantly associated with immune cells. In addition, we have identified potential transcription factors associated with these key genes using the Cistrome database, thus contributing to a deeper understanding of the regulatory network of these gene expressions.

CONCLUSIONS

This eQTLs Mendelian randomization study identified four key genes (GZMH, COTL1, CSTA, and CD14) causally associated with COPD, providing new insights for prevention and treatment of COPD.