Publications

PURPOSE OF REVIEW

Studies have illustrated that the healthy human microbiome (i.e. the communities of microbes, their genomic content and interaction with the host) plays a role in the maintenance of immune homeostasis. Perturbation of these communities is an emerging characteristic of an increasing number of inflammatory diseases. The goal of this article is to review the current literature on both respiratory and gut microbiomes and their established relationship with allergy and asthma.

RECENT FINDINGS

Multiple studies have demonstrated airway microbiota dysbiosis, characterized by Proteobacteria expansion in the lower airways, to be a consistent trait of established adult asthma. Members of this phylum are associated with disease features such as bronchial hyperreactivity or corticosteroid resistance. Emerging evidence implicates the neonatal gut microbiome as playing a significant role in the development of childhood atopy, a common precursor to asthma. Murine studies have demonstrated that specific bacterial species (e.g. Lactobacillus johnsonii, Bacteroides fragilis) and microbial metabolites (e.g. the short-chain fatty acid propionate), when supplemented to animals, confer protection against allergen-induced airway disorders.

SUMMARY

The emerging view of atopy and asthma is one consistently related to inappropriate microbial community composition and function in both the airway and gastrointestinal tract. This opens up the possibility that strategies to rationally manipulate microbiota at these sites may represent a novel approach to disease prevention or management.

The fifth Jack Pepys Workshop on Asthma in the Workplace focused on the similarities and differences of work-related asthma (WRA) and non-work-related asthma (non-WRA). WRA includes occupational asthma (OA) and work-exacerbated asthma (WEA). There are few biological differences in the mechanisms of sensitization to environmental and occupational allergens. Non-WRA and OA, when due to high-molecular-weight agents, are both IgE mediated; it is uncertain whether OA due to low-molecular-weight agents is also IgE mediated. Risk factors for OA include female sex, a history of upper airway symptoms, and a history of bronchial hyperresponsiveness. Atopy is a risk factor for OA due to high-molecular-weight agents, and exposure to cleaning agents is a risk factor for both OA and non-WRA. WEA is important among workers with preexisting asthma and may overlap with irritant-induced asthma, a type of OA. Induced sputum cytology can confirm airway inflammation, but specific inhalation challenge is the reference standard diagnostic test. Inhalation challenges are relatively safe, with the most severe reactions occurring with low-molecular-weight agents. Indirect health care costs account for about 50% of total asthma costs. Workers with poor asthma control (WRA or non-WRA) are less likely to be employed. Income loss is a major contributor to the indirect costs of WRA. Overall, asthma outcomes probably are worse for adult-onset than for childhood-onset asthma but better for OA than adult-onset non-WRA. Important aspects of management of OA are rapid and proper confirmation of the diagnosis and reduction of exposure to sensitizers or irritants at work and home.

The Second European Round Table on the Future Management of HIV took place in Barcelona, 10-11 October 2014 and focused on the HIV-1 reservoir, strategies for HIV cure and primary HIV infection (PHI). Important issues in the HIV-1 reservoir research field are the validity of reservoir measurement techniques and the potential of new drugs to target latently infected cells. Current HIV-1 cure concepts are based on theoretical assumptions of biologically plausible mechanisms, supported by several clinical observations. Three main potential strategies are under investigation in order to achieve a sterilising cure or maintain HIV-1 remission: latency reversal resulting in antigen expression and viral cytolysis or immune targeted cell-death; immunological control of the reservoir; or replacement of the complete autologous haematopoietic and lymphoid stem-cell repertoire by transplantation. An interesting opportunity for restricting the size of the reservoir entails the early initiation of antiretroviral treatment (ART) during PHI. In terms of the reservoir, early treatment limits its size, alters its composition, and restricts the genetic variability of integrated proviral HIV-1 DNA. The challenges ahead involve the identification of patients undergoing seroconversion to HIV-1 and the prompt initiation of treatment. How the seemingly beneficial impact of early treatment will make cure more feasible, and whether the positive effects of the cure efforts outweigh the potentially negative impact of life-long ART, are important aspects of future collaborative research prospects.

RATIONALE

Stress is associated with asthma morbidity in Puerto Ricans (PRs), who have reduced bronchodilator response (BDR).

OBJECTIVES

To examine whether stress and/or a gene regulating anxiety (ADCYAP1R1) is associated with BDR in PR and non-PR children with asthma.

METHODS

This was a cross-sectional study of stress and BDR (percent change in FEV1 after BD) in 234 PRs ages 9-14 years with asthma. We assessed child stress using the Checklist of Children's Distress Symptoms, and maternal stress using the Perceived Stress Scale. Replication analyses were conducted in two cohorts. Polymorphisms in ADCYAP1R1 were genotyped in our study and six replication studies. Multivariable models of stress and BDR were adjusted for age, sex, income, environmental tobacco smoke, and use of inhaled corticosteroids.

MEASUREMENTS AND MAIN RESULTS

High child stress was associated with reduced BDR in three cohorts. PR children who were highly stressed (upper quartile, Checklist of Children's Distress Symptoms) and whose mothers had high stress (upper quartile, Perceived Stress Scale) had a BDR that was 10.2% (95% confidence interval, 6.1-14.2%) lower than children who had neither high stress nor a highly stressed mother. A polymorphism in ADCYAP1R1 (rs34548976) was associated with reduced BDR. This single-nucleotide polymorphism is associated with reduced expression of the gene for the β2-adrenergic receptor (ADRB2) in CD4(+) lymphocytes of subjects with asthma, and it affects brain connectivity of the amygdala and the insula (a biomarker of anxiety).

CONCLUSIONS

High child stress and an ADCYAP1R1 single-nucleotide polymorphism are associated with reduced BDR in children with asthma. This is likely caused by down-regulation of ADRB2 in highly stressed children.

IMPORTANCE

Serious illness impairs function and threatens survival. Patients facing serious illness value shared decision making, yet few decision aids address the needs of this population.

OBJECTIVE

To perform a systematic review of evidence about decision aids and other exportable tools that promote shared decision making in serious illness, thereby (1) identifying tools relevant to the treatment decisions of seriously ill patients and their caregivers, (2) evaluating the quality of evidence for these tools, and (3) summarizing their effect on outcomes and accessibility for clinicians.

EVIDENCE REVIEW

We searched PubMed, CINAHL, and PsychInfo from January 1, 1995, through October 31, 2014, and identified additional studies from reference lists and other systematic reviews. Clinical trials with random or nonrandom controls were included if they tested print, video, or web-based tools for advance care planning (ACP) or decision aids for serious illness. We extracted data on the study population, design, results, and risk for bias using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. Each tool was evaluated for its effect on patient outcomes and accessibility.

FINDINGS

Seventeen randomized clinical trials tested decision tools in serious illness. Nearly all the trials were of moderate or high quality and showed that decision tools improve patient knowledge and awareness of treatment choices. The available tools address ACP, palliative care and goals of care communication, feeding options in dementia, lung transplant in cystic fibrosis, and truth telling in terminal cancer. Five randomized clinical trials provided further evidence that decision tools improve ACP documentation, clinical decisions, and treatment received.

CONCLUSIONS AND RELEVANCE

Clinicians can access and use evidence-based tools to engage seriously ill patients in shared decision making. This field of research is in an early stage; future research is needed to develop novel decision aids for other serious diagnoses and key decisions. Health care delivery organizations should prioritize the use of currently available tools that are evidence based and effective.

IMPORTANCE

Increasing numbers of older, community-dwelling adults have functional impairments that prevent them from leaving their homes. It is uncertain how many people who live in the United States are homebound.

OBJECTIVES

To develop measures of the frequency of leaving and ability to leave the home and to use these measures to estimate the size of the homebound population in the US population.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional data from the National Health and Aging Trends Study collected in 2011 in the contiguous United States. Participants were a nationally representative sample of 7603 noninstitutionalized Medicare beneficiaries 65 years and older.

MAIN OUTCOMES AND MEASURES

We defined homebound persons as those who never (completely homebound) or rarely (mostly homebound) left the home in the last month. We defined semihomebound persons as those who only left the home with assistance or had difficulty or needed help leaving the home. We compared demographic, clinical, and health care utilization characteristics across different homebound status categories.

RESULTS

In 2011, the prevalence of homebound individuals was 5.6% (95% CI, 5.1%-6.2%), including an estimated 395,422 people who were completely homebound and 1,578,984 people who were mostly homebound. Among semihomebound individuals, the prevalence of those who never left home without personal assistance was 3.3% (95% CI, 2.8%-3.8%), and the prevalence of those who required help or had difficulty was 11.7% (95% CI, 10.9%-12.6%). Completely homebound individuals were more likely to be older (83.2 vs 74.3 years, P < .001), female (67.9% vs 53.4%, P < .006), and of nonwhite race (34.1% vs 17.6%, P < .001) and have less education and income than nonhomebound individuals. They also had more chronic conditions (4.9 vs 2.5) and were more likely to have been hospitalized in the last 12 months (52.1% vs 16.2%) (P < .001 for both). Only 11.9% of completely homebound individuals reported receiving primary care services at home.

CONCLUSIONS AND RELEVANCE

In total, 5.6% of the elderly, community-dwelling Medicare population (approximately 2 million people) were completely or mostly homebound in 2011. Our findings can inform improvements in clinical and social services for these individuals.

BACKGROUND

FVC outcomes in clinical trials on idiopathic pulmonary fibrosis (IPF) can be substantially influenced by the analytic methodology and the handling of missing data. We conducted a series of sensitivity analyses to assess the robustness of the statistical finding and the stability of the estimate of the magnitude of treatment effect on the primary end point of FVC change in a phase 3 trial evaluating pirfenidone in adults with IPF.

METHODS

Source data included all 555 study participants randomized to treatment with pirfenidone or placebo in the Assessment of Pirfenidone to Confirm Efficacy and Safety in Idiopathic Pulmonary Fibrosis (ASCEND) study. Sensitivity analyses were conducted to assess whether alternative statistical tests and methods for handling missing data influenced the observed magnitude of treatment effect on the primary end point of change from baseline to week 52 in FVC.

RESULTS

The distribution of FVC change at week 52 was systematically different between the two treatment groups and favored pirfenidone in each analysis. The method used to impute missing data due to death had a marked effect on the magnitude of change in FVC in both treatment groups; however, the magnitude of treatment benefit was generally consistent on a relative basis, with an approximate 50% reduction in FVC decline observed in the pirfenidone group in each analysis.

CONCLUSIONS

Our results confirm the robustness of the statistical finding on the primary end point of change in FVC in the ASCEND trial and corroborate the estimated magnitude of the pirfenidone treatment effect in patients with IPF.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01366209; URL: www.clinicaltrials.gov.