Adherence pattern to study drugs in clinical trials by patients with cystic fibrosis

Self-management intervention to reduce pulmonary exacerbations by supporting treatment adherence in adults with cystic fibrosis: a randomised controlled trial

Introduction

Recurrent pulmonary exacerbations lead to progressive lung damage in cystic fibrosis (CF). Inhaled medications (mucoactive agents and antibiotics) help prevent exacerbations, but objectively measured adherence is low. We investigated whether a multi-component (complex) self-management intervention to support adherence would reduce exacerbation rates over 12 months.

Methods

Between October 2017 and May 2018, adults with CF (aged ≥16 years; 19 UK centres) were randomised to the intervention (data-logging nebulisers, a digital platform and behavioural change sessions with trained clinical interventionists) or usual care (data-logging nebulisers). Outcomes included pulmonary exacerbations (primary outcome), objectively measured adherence, body mass index (BMI), lung function (FEV₁) and Cystic Fibrosis Questionnaire-Revised (CFQ-R). Analyses were by intent to treat over 12 months.

Results

Among intervention (n=304) and usual care (n=303) participants (51% female, median age 31 years), 88% completed 12-month follow-up. Mean exacerbation rate was 1.63/year with intervention and 1.77/year with usual care (adjusted ratio 0.96; 95% CI 0.83 to 1.12; p=0.64). Adjusted mean differences (95% CI) were in favour of the intervention versus usual care for objectively measured adherence (9.5% (8.6% to 10.4%)) and BMI (0.3 (0.1 to 0.6) kg/m²), with no difference for %FEV₁ (1.4 (−0.2 to 3.0)). Seven CFQ-R subscales showed no between-group difference, but treatment burden reduced for the intervention (3.9 (1.2 to 6.7) points). No intervention-related serious adverse events occurred.

Conclusions

While pulmonary exacerbations and FEV₁ did not show statistically significant differences, the intervention achieved higher objectively measured adherence versus usual care. The adherence difference might be inadequate to influence exacerbations, though higher BMI and lower perceived CF treatment burden were observed.

The Prevalence and Effect of Comorbid Cystic Fibrosis and Attention Deficit Hyperactivity Disorders on Hospitalizations: A Retrospective Analysis

Introduction: The prevalence of attention-deficit/hyperactivity disorder (ADHD) in pediatric cystic fibrosis (CF) patients is comparable to the general population, but the effects of ADHD on CF treatment and the outcomes have been minimally investigated.

Methods: Two cohorts were retrospectively reviewed, pediatric patients with comorbid CF/ADHD and patients with CF only. Each patient with CF/ADHD was age and sex-matched to a CF-only patient based on their most recent pulmonary office visit. Each patient was reviewed for forced expiratory volume in one-second percent predicted (FEV1%pred), body mass index (BMI) percentile, and hospitalizations for one year prior to the last pulmonary visit.

Results: A total of 624 patients with CF were identified, with 52 having co-morbid CF/ADHD (8.3%). Of those identified, 46 met inclusion criteria and were analyzed in the CF/ADHD cohort. The mean total hospital admissions between the CF/ADHD cohort and the CF-only cohort were not statistically significant (2.22 vs 1.834, p=.467). The difference between the BMI percentiles was not statistically significant (48.634 vs 38.634, p=.135). The difference between FEV1%pred was statistically significant at 84% for the CF/ADHD group and 74% for the CF-only group (p=.042).

Conclusion: The difference in total hospital admissions between the CF/ADHD cohort and the CF-only cohort did not reach statistical significance, but the study was underpowered. There was a significant difference between FEV1%pred between the two groups, in favor of the comorbid CF/ADHD population. More research is needed to further evaluate the effects of a comorbid ADHD diagnosis on outcomes in the CF pediatric population.

Do cystic fibrosis centres with the lowest FEV1 still use the least amount of intravenous antibiotics? A registry-based comparison of intravenous antibiotic use among adult CF centres in the UK

BACKGROUND

The Epidemiologic Study of Cystic Fibrosis using 1995-1996 and 2003-2005 data found that CF centres with lowest FEV₁ tended to use fewer intravenous antibiotics. We repeated the analyses using 2013-2014 UK CF registry data to determine if this was still the case.

METHODS

Analysing data for 2013 and 2014 separately, 28 adult CF centres were ranked according to median % age-adjusted FEV₁. The top 7 centres were placed in the 'upper quarter' (best FEV₁), the bottom 7 centres in 'lower quarter' (lowest FEV₁), and the rest in 'middle half'. IV use was stratified according to %FEV₁, then compared between the three groups.

RESULTS

Centres in the 'upper quarter' and 'middle half' used significantly more IV antibiotics compared to centres in the 'lower quarter' (van Elteren test P-value<0.001). Regression analyses showed that people with CF attending centres in the 'upper quarter' or 'middle half' are 30-50% more likely to receive at least one IV course per year compared to people attending centres in the 'lower quarter'.

CONCLUSIONS

CF centres with lowest FEV₁ are still distinguished by lower use of intravenous antibiotics.

Cystic fibrosis year in review 2016

In this article, we highlight cystic fibrosis (CF) research and case reports published in Pediatric Pulmonology during 2016. We also include articles from a variety of journals that are thematically related to these articles, or are of special interest to clinicians.

An Early Health Economic Analysis of the Potential Cost Effectiveness of an Adherence Intervention to Improve Outcomes for Patients with Cystic Fibrosis

BACKGROUND

Cystic fibrosis (CF) negatively impacts upon health-related quality of life and survival. Adherence to nebulised treatments is low; improving adherence is hypothesised to reduce rates of exacerbation requiring intravenous antibiotics and lung function decline.

OBJECTIVE

A state transition model was developed to assess the cost effectiveness of an intervention aimed at increasing patient adherence to nebulised and inhaled antibiotics compared with current CF care, in advance of the forthcoming CFHealthHub randomised controlled trial (RCT).

METHODS

The model estimated the costs and health outcomes for each option from the perspective of the UK National Health Service and Personal Social Services over a lifetime horizon. Health gains were valued in terms of quality-adjusted life-years (QALYs) gained. Forced expiratory volume in 1 second (FEV₁) trajectories were predicted over three lung function strata: (1) FEV₁ ≥70%, (2) FEV₁ 40-69% and (3) FEV₁ <40%. Additional states were included to represent 'post-lung transplantation' and 'dead'. The model was populated using CF Registry data, literature and expert opinion. Costs were presented at 2016 values. Uncertainty was assessed using deterministic and probabilistic sensitivity analyses.

RESULTS

If effective, the adherence intervention is expected to produce an additional 0.19 QALYs and cost savings of £64,078 per patient. Across all analyses, the intervention dominated current care. Over a 5-year period, the intervention is expected to generate cost savings of £49.5 million for the estimated 2979 patients with CF with Pseudomonas aeruginosa currently aged ≥16 years in the UK. If applied to a broader population of adult patients with CF receiving any nebulised therapy, the expected savings could be considerably greater.

CONCLUSIONS

If effective, the adherence intervention is expected to produce additional health gains at a lower cost than current CF care. However, the economic analysis should be revisited upon completion of the full RCT. More generally, the analysis suggests that considerable gains could be accrued through the implementation of adherence interventions that shift care from expensive hospital-based rescue to community-based prevention.

An empirical method to cluster objective nebulizer adherence data among adults with cystic fibrosis

BACKGROUND

The purpose of using preventative inhaled treatments in cystic fibrosis is to improve health outcomes. Therefore, understanding the relationship between adherence to treatment and health outcome is crucial. Temporal variability, as well as absolute magnitude of adherence affects health outcomes, and there is likely to be a threshold effect in the relationship between adherence and outcomes. We therefore propose a pragmatic algorithm-based clustering method of objective nebulizer adherence data to better understand this relationship, and potentially, to guide clinical decisions.

METHODS TO CLUSTER ADHERENCE DATA

This clustering method consists of three related steps. The first step is to split adherence data for the previous 12 months into four 3-monthly sections. The second step is to calculate mean adherence for each section and to score the section based on mean adherence. The third step is to aggregate the individual scores to determine the final cluster ("cluster 1" = very low adherence; "cluster 2" = low adherence; "cluster 3" = moderate adherence; "cluster 4" = high adherence), and taking into account adherence trend as represented by sequential individual scores. The individual scores should be displayed along with the final cluster for clinicians to fully understand the adherence data.

THREE ILLUSTRATIVE CASES

We present three cases to illustrate the use of the proposed clustering method.

CONCLUSION

This pragmatic clustering method can deal with adherence data of variable duration (ie, can be used even if 12 months' worth of data are unavailable) and can cluster adherence data in real time. Empirical support for some of the clustering parameters is not yet available, but the suggested classifications provide a structure to investigate parameters in future prospective datasets in which there are accurate measurements of nebulizer adherence and health outcomes.