The impact of health literacy interventions on glycemic control and self-management outcomes among type 2 diabetes mellitus: A systematic review.

Diabetes imposes an increasing health and economic burden on individuals living with it and their societies worldwide. Glycemic control is necessary to reduce morbidity and mortality of type 2 diabetes mellitus (T2DM). Self-management is the primary tool for managing diabetes. Health literacy (HL) is the primary driver of self-management activities. The aim of this review is to evaluate the impact of HL interventions on glycemic control and self-management outcomes among T2DM. MEDLINE, CINAHL, PubMed, Cochrane, Scopus, and Web of Science were searched for eligible papers. Fifteen randomized controlled trials published in English between 1997 and 2021, used HL-driven intervention, and measured the level of glycohemoglobin A1c (HbA1c) and self-management of T2DM patients were included in this review. The findings showed that HL-driven intervention had a positive impact on glycemic control and improved self-management behaviors. The level of glycemic control and self-management skills were improved through individual and telephone-based intervention respectively. Community worker-led interventions were effective in improvements in diabetes knowledge and self-care behaviors; however, nurse-led interventions were effective in glycemic control. Better glycemic control is achieved in hospital settings compared to outpatient settings. HL interventions yielded better improvement in self-management among people with longer diabetes duration (more than 7 years). It was possible to achieve a large reduction in HbA1c level after a 3-month intervention in hospital settings. HL-driven interventions are effective in glycemic and diabetes self-management outcomes.

Effectiveness of patient activation interventions on chronic obstructive pulmonary disease self-management outcomes: A systematic review.

BACKGROUND: Chronic obstructive pulmonary disease is the third leading cause of death worldwide. Although there is currently no cure for chronic obstructive pulmonary disease, the available self-management strategies can result in improving the symptoms, slowing the disease progression, reducing the frequency of acute exacerbations, improving the patients' quality of life and minimising health care utilisation-associated costs. Patient activation is often considered an essential driver of self-management; however, there are contradictory evidence about its impact on chronic obstructive pulmonary disease self-management. OBJECTIVE: This review aims to fill this gap by collating the available evidence on the effectiveness of patient activation-driven chronic obstructive pulmonary disease self-management interventions. METHODS: Databases including MEDLINE, Academic Search Complete, CINAHL Plus, Science Citation Index, Social Sciences Citation Index, Scopus, APA PsychInfo, EMBASE and ScienceDirect were searched for randomised controlled trials of patient activation-driven chronic obstructive pulmonary disease self-management interventions between 2004 and July 2020. The search terms included chronic obstructive pulmonary disease, self-management/self-care and patient activation/patient engagement. FINDINGS: The initial search resulted in 645 articles, and after reviewing, 10 randomised controlled trials met the inclusion and exclusion criteria. Our review found that patient activation level had a positive association with chronic obstructive pulmonary disease self-management and clinical outcomes, and higher patient activation levels led to better outcomes. The interventions also led to moderate improvements in patient activation level. However, improved patient activation levels did not improve hospitalisation rates, quality of life and mental health. CONCLUSION: Our findings suggest that patient activation can be used as a reliable tool for improving chronic obstructive pulmonary disease self-management and clinical outcomes; however, it should encompass all aspects of patient activation, especially the emotional aspect.

Effectiveness of Health Literacy Interventions on COPD Self-Management Outcomes in Outpatient Settings: A Systematic Review.

Chronic obstructive pulmonary disease (COPD) is a chronic progressive lung disease which imposes significant health and economic burdens on societies. Self-management is beneficial in controlling and managing COPD and health literacy (HL) is a major driver of COPD self-management. This review aims to summarize the most recent evidence on the effectiveness of HL driven COPD self-management interventions using randomized controlled trials (RCTs). Eight data bases including Science Citation Index, Academic Search Complete, Social Sciences Citation Index, CINAHL Plus, APA PsycInfo, MEDLINE, Scopus and ScienceDirect were searched to find eligible RCTs assessing the effectiveness of HL interventions on COPD self-management outcomes in outpatient settings between 2008 and February 2020. Ten RCTs met the eligibility criteria. The review found that HL interventions led to moderate improvements in physical activity levels (four out of seven trials) and COPD knowledge (three out of six trials). Surprisingly, none of the RCTs led to significant improvement in medication adherence, which warrants further studies. Furthermore, there were inconclusive findings regarding other COPD self-management outcomes such as smoking cessation, medication adherence, dyspnea, mental health, hospital admissions and health related quality of life.

Inhaler Technique in Asthma: How Does It Relate to Patients' Preferences and Attitudes Toward Their Inhalers?

BACKGROUND: Correct inhaler technique can increase medication efficacy, reducing both dose and side effects. Patient preference for inhaler device has not been fully explored, and we hypothesized that if patients have a preference and can choose their inhaler, they might be more likely to use it correctly. Our aim was to determine the preferences, attitudes, and perceptions of patients with asthma toward their inhalers, and to evaluate whether any of these factors were related to inhalation technique. METHODS: Twenty-five patients with asthma (mean age 43.1 years) participated. Qualitative semi-structured interviews and quantitative patient satisfaction and preference questionnaires (PASAPQ) were used to explore patients' preferences, attitudes, and perceptions about their inhalers. Objective inhalation technique assessment was performed. Data were triangulated to identify characteristics that could indicate a relationship between inhaler technique, satisfaction, preference, and decision making. RESULTS: Themes from qualitative interviews were as follows: asthma inhalers and expectations; inhaler preference; characteristics of an ideal inhaler; perceived effectiveness of inhalers; and inhalers and patient decision making. PASAPQ scores indicated that all patients were at least "somewhat satisfied" with their inhalers, regardless of technique. Only 12% of inhalers were used correctly, despite pilot PASAPQ data suggesting that most patients were confident with their technique. The inhaler technique was unlikely to be related to satisfaction, perception of inhaler devices, or choice in device selection. Patients with correct inhaler technique were more aware of their asthma and expressed motivation to achieve optimal asthma control. CONCLUSIONS: The majority of the asthmatic patients did not use their inhaler(s) correctly, despite most having confidence in their technique. Patients attributed confidence in their inhaler technique to their belief that their inhaler was effective. Most patients had not been involved in decision making about which inhalation device to use. These findings highlight the lack of understanding of the important role of correct inhaler technique in asthma management.

Ventilation heterogeneity is associated with airway responsiveness in asthma but not COPD.

Airway hyperresponsiveness (AHR) occurs in both asthma and COPD. In older people with asthma, AHR is associated with increased acinar ventilation heterogeneity, but it is unknown if this association exists in COPD. Thirty one COPD and 19 age-matched asthmatic subjects had measures of spirometry, lung volumes, exhaled nitric oxide, ventilation heterogeneity, and methacholine challenge. Indices of acinar (Sacin) and conducting (Scond) airway ventilation heterogeneity were calculated from the multiple breath nitrogen washout. Predictors of AHR were then determined. In COPD, AHR was predicted by lower Sacin and lower FVC (model r(2)=0.35, p=0.001). In asthma, AHR was predicted by higher Sacin and higher residual volume (model r(2)=0.62, p<0.001). These findings suggest that airway responsiveness in COPD and asthma is determined by underlying disease-specific processes, rather than a common pattern of physiological abnormality.

Effect of methacholine on peripheral lung mechanics and ventilation heterogeneity in asthma.

The forced oscillation technique (FOT) and multiple-breath nitrogen washout (MBNW) are noninvasive tests that are potentially sensitive to peripheral airways, with MBNW indexes being especially sensitive to heterogeneous changes in ventilation. The objective was to study methacholine-induced changes in the lung periphery of asthmatic patients and determine how changes in FOT variables of respiratory system reactance (Xrs) and resistance (Rrs) and frequency dependence of resistance (Rrs5-Rrs19) can be linked to changes in ventilation heterogeneity. The contributions of air trapping and airway closure, as extreme forms of heterogeneity, were also investigated. Xrs5, Rrs5, Rrs19, Rrs5-Rrs19, and inspiratory capacity (IC) were calculated from the FOT. Ventilation heterogeneity in acinar and conducting airways, and trapped gas (percent volume of trapped gas at functional residual capacity/vital capacity), were calculated from the MBNW. Measurements were repeated following methacholine. Methacholine-induced airway closure (percent change in forced vital capacity) and hyperinflation (change in IC) were also recorded. In 40 mild to moderate asthmatic patients, increase in Xrs5 after methacholine was predicted by increases in ventilation heterogeneity in acinar airways and forced vital capacity (r(2) = 0.37, P < 0.001), but had no correlation with ventilation heterogeneity in conducting airway increase or IC decrease. Increases in Rrs5 and Rrs5-Rrs19 after methacholine were not correlated with increases in ventilation heterogeneity, trapped gas, hyperinflation, or airway closure. Increased reactance in asthmatic patients after methacholine was indicative of heterogeneous changes in the lung periphery and airway closure. By contrast, increases in resistance and frequency dependence of resistance were not related to ventilation heterogeneity or airway closure and were more indicative of changes in central airway caliber than of heterogeneity.

The role of the small airways in the clinical expression of asthma in adults.

BACKGROUND: The clinical relevance of increased ventilation heterogeneity, a marker of small-airways disease, in asthmatic patients is unclear. Ventilation heterogeneity is an independent determinant of airway hyperresponsiveness (AHR), improves with bronchodilators and inhaled corticosteroids (ICSs), and worsens during exacerbations, but its relationship to asthma control is unknown. OBJECTIVE: We sought to determine the association between ventilation heterogeneity and current asthma control before and after ICS treatment. METHODS: Adult subjects with asthma had lung function and asthma control (5-item Asthma Control Questionnaire [ACQ-5 score] ≥1.5 = poorly controlled, ACQ-5 score ≤0.75 = well controlled) measured at baseline. A subgroup with AHR had repeat measurements after 3 months of high-dose ICS treatment. The indices of ventilation heterogeneity in the regions of the lung where gas transport occurs predominantly through convection (ventilation heterogeneity in convection-dependent airways [Scond]) and through diffusion (ventilation heterogeneity in diffusion-dependent airways [Sacin]) were derived by using the multiple-breath nitrogen washout technique. RESULTS: At baseline (n = 105), subjects with poorly controlled asthma had worse FEV(1), fraction of exhaled nitric oxide measured at 200 mL/s (Feno), Scond, and Sacin values. In the treatment group (n = 50) spirometric, Feno, residual volume (RV)/total lung capacity (TLC), AHR, and Scond values significantly improved. Asthma control also improved (mean ACQ-5 score, 1.3-0.7; P < .0001). The change in ACQ-5 score correlated with changes in Feno (r(s) = 0.31, P = .03), Sacin (r(s) = 0.32, P = .02), and Scond (r(s) = 0.41, P = .003) values. The independent predictors of a change in asthma control were changes in Scond and Sacin values (model r(2) = 0.20, P = .005). CONCLUSIONS: Current asthma control is associated with markers of small-airways disease. Improvements in ventilation heterogeneity with anti-inflammatory therapy are associated with improvements in symptoms. Sensitive measures of small-airway function might be useful in monitoring the response to therapy in asthmatic subjects.

Predictors of airway hyperresponsiveness differ between old and young patients with asthma.

BACKGROUND: Age-related increases in morbidity and mortality due to asthma may be due to changes in pathophysiology as patients with asthma get older. There is limited knowledge about the effects of age on the predictors of airway hyperresponsiveness (AHR), a key feature of asthma. The aim of this study was to determine if the pathophysiologic predictors of AHR, including inflammation, ventilation heterogeneity, and airway closure, differed between young and old patients with asthma. METHODS: Sixty-one young (18-46 years) and 43 old (50-80 years) patients with asthma had lung function, lung volumes, fraction of exhaled nitric oxide, ventilation heterogeneity, and airway responsiveness to methacholine measured. Airway response to methacholine was measured by the dose-response slope, as the percent fall in FEV(1) per micromole of methacholine. Indices of ventilation heterogeneity were calculated for convection-dependent and diffusion-dependent airways. RESULTS: In young patients with asthma, the independent predictors of AHR were convection-dependent ventilation heterogeneity, exhaled nitric oxide, and % predicted FEV(1)/FVC (model r(2) = 0.51, P < .0001). In old patients with asthma, the independent predictors of airway responsiveness were % predicted residual volume, diffusion-dependent ventilation heterogeneity, and % predicted FEV(1) (model r(2) = 0.57, P < .0001). CONCLUSIONS: In old patients with asthma, AHR is predicted by gas trapping and ventilation heterogeneity in peripheral, diffusion-dependent airways. In the young, it is predicted by ventilation heterogeneity in less peripheral conducting airways and by inflammation. These findings suggest that there are differences in the pathophysiologic determinants of AHR between young and old patients with asthma.

Obesity is a determinant of asthma control independent of inflammation and lung mechanics.

BACKGROUND: It is unclear why obesity is associated with worse asthma control. We hypothesized that (1) obesity affects asthma control independent of spirometry, airway inflammation, and airway hyperresponsiveness (AHR) and (2) residual symptoms after resolution of inflammation are due to obesity-related changes in lung mechanics. METHODS: Forty-nine subjects with asthma underwent the following tests, before and after 3 months of high-dose inhaled corticosteroid (ICS) treatment: five-item asthma control questionnaire (ACQ-5), spirometry, fraction of exhaled nitric oxide (Feno), methacholine challenge, and the forced oscillation technique, which allows for the calculation of respiratory system resistance (Rrs) and respiratory system reactance (Xrs) as indicators of airway caliber and elastic load, respectively. The effects of treatment were assessed by BMI group (18.5-24.9, 25-29.9, and ≥ 30 kg/m²) using analysis of variance. Multiple regression analyses determined the independent predictors of ACQ-5 results. RESULTS: At baseline, the independent predictors of ACQ-5 results were FEV(1), Feno, and BMI (model r² = 0.38, P < .001). After treatment, asthma control, spirometry, airway inflammation, and AHR improved similarly across BMI groups. The independent predictors of ACQ-5 results after treatment were Rrs and BMI (model r² = 0.42, P < .001). CONCLUSIONS: BMI is a determinant of asthma control independent of airway inflammation, lung function, and AHR. After ICS treatment, BMI again predicts ACQ-5 results, but independent of obesity-related changes in lung mechanics.

Sleep disturbance in persistent allergic rhinitis measured using actigraphy.

BACKGROUND: Tiredness, fatigue, and impaired quality of life are common in patients with persistent allergic rhinitis (PAR). These symptoms may also be associated with reduced sleep quality in individuals with rhinitis. OBJECTIVE: To determine whether sleep disturbance can be detected using actigraphy in patients with PAR. METHODS: Ten house dust mite-allergic rhinitic patients and 10 nonallergic nonrhinitic control subjects were studied for 5 consecutive days and night. Continuous activity monitoring during the study period using actigraphy was used to obtain markers of sleep quality, such as sleep onset, sleep duration, and sleep fragmentation. In addition, participants recorded in a sleep diary the time they went to bed, the time they went to sleep, the time they awoke, and the quality of their sleep. RESULTS: Allergic rhinitic patients were found to have an increased fragmentation index value, indicative of reduced sleep quality and increased sleep disturbance, compared with the control group (P = .007). CONCLUSIONS: Using actigraphy, we identified specific sleep disturbances in patients with PAR that may result in the increased tiredness, fatigue, and impaired quality of life typically experienced in such patients.

Ventilation heterogeneity is a major determinant of airway hyperresponsiveness in asthma, independent of airway inflammation.

BACKGROUND: Airway hyperresponsiveness is the ability of airways to narrow excessively in response to inhaled stimuli and is a key feature of asthma. Airway inflammation and ventilation heterogeneity have been separately shown to be associated with airway hyperresponsiveness. A study was undertaken to establish whether ventilation heterogeneity is associated with airway hyperresponsiveness independently of airway inflammation in subjects with asthma and to determine the effect of inhaled corticosteroids on this relationship. METHODS: Airway inflammation was measured in 40 subjects with asthma by exhaled nitric oxide, ventilation heterogeneity by multiple breath nitrogen washout and airway hyperresponsiveness by methacholine challenge. In 18 of these subjects with uncontrolled symptoms, measurements were repeated after 3 months of treatment with inhaled beclomethasone dipropionate. RESULTS: At baseline, airway hyperresponsiveness was independently predicted by airway inflammation (partial r2 = 0.20, p<0.001) and ventilation heterogeneity (partial r2 = 0.39, p<0.001). Inhaled corticosteroid treatment decreased airway inflammation (p = 0.002), ventilation heterogeneity (p = 0.009) and airway hyperresponsiveness (p<0.001). After treatment, ventilation heterogeneity was the sole predictor of airway hyperresponsiveness (r2 = 0.64, p<0.001). CONCLUSIONS: Baseline ventilation heterogeneity is a strong predictor of airway hyperresponsiveness, independent of airway inflammation in subjects with asthma. Its persistent relationship with airway hyperresponsiveness following anti-inflammatory treatment suggests that it is an important independent determinant of airway hyperresponsiveness. Normalisation of ventilation heterogeneity is therefore a potential goal of treatment that may lead to improved long-term outcomes.

Effects of methacholine on small airway function measured by forced oscillation technique and multiple breath nitrogen washout in normal subjects.

The multiple breath nitrogen washout (MBNW) can be analysed to produce the parameters Scond and Sacin as measures of ventilation heterogeneity in conductive and acinar airways, respectively. The derivation of these parameters is based on a model of pulmonary ventilation and results of similar modelling suggest that respiratory system conductance (Grs) measured by forced oscillation technique (FOT) is also sensitive to heterogeneity and to airway closure. Therefore, Scond, the volume of gas trapping at FRC (VtrappedFRC) and Grs may be inter-related parameters. These relationships were examined in 12 normals under baseline and bronchoconstricted states. Specific Grs was measured at 5Hz (sGrs5=Grs5/FRC) and Scond, Sacin and VtrappedFRC by MBNW, before and after methacholine challenge. Scond was independently predicted by VtrappedFRC and FRC in a multivariate model (R2=0.68, p=0.002). Post methacholine challenge, Scond related only to VtrappedFRC (R2=0.79, p<0.0001). The absolute change in Scond induced by methacholine challenge were predicted by the changes in VtrappedFRC and sGrs5 in a multivariate model (R2=0.82, p=0.0002). Sacin was unrelated to VtrappedFRC and sGrs5 before and after methacholine challenge. In conclusion, Scond and sGrs5 are measurements that are sensitive to changes occurring to the function of peripheral conducting airways, in particular heterogeneity and airway closure, while Sacin and presumably heterogeneity in terminal airways, are independent of these. Scond is also related to lung size. We review the current state of knowledge of FOT and MBNW in obstructive lung diseases and discuss future research directions.

A comparison of two methods for measuring airway distensibility: nitrogen washout and the forced oscillation technique.

The measurement of airway stiffness is an important tool for studying airway remodelling in asthma. The relationship between airway calibre and lung volume (airway distensibility) was measured by forced oscillation technique (FOT) and compared with that measured by single-breath nitrogen washout (SBNW). In four non-asthmatic healthy subjects and three asthmatics, anatomical dead space (VDF) was measured by SBNW and respiratory system conductance (Grs) was measured by FOT at 6 Hz. During SBNW testing, 0.51 oxygen boluses were inhaled from three different lung volumes: functional residual capacity (FRC), 11 above FRC and near total lung capacity (TLC). Following inhalation of the oxygen bolus subjects exhaled to residual volume and then inhaled to TLC. During FOT, subjects breathed 0.5-1.01 tidal volumes but with gradually increasing end-expiratory lung volume until close to TLC, then returned to normal breathing before inhaling to TLC. This was also repeated but with reducing lung volume from TLC. Absolute lung volumes were measured by body plethysmography and related to volumes during FOT and SBNW by reference to TLC obtained at the end of each SBNW or FOT test manoeuvre. Distensibility was calculated as the linear regression slopes of VDF or Grs versus lung volume. Distensibility measured by VDF ranged 16-37 ml 1(-1) lung volume and by Grs it ranged 0.06-0.19 1 s(-1) cmH2O(-1) 1(-1) lung volume. Both distensibility measurements were correlated (Pearson's R2 = 0.91, p = 0.001). The SBNW and FOT are comparable methods for measuring airway distensibility and may have similar clinical usefulness. However, further studies are required to make any specific inferences about the relationship between airway distensibility by FOT and airway remodelling.

A single high dose of inhaled corticosteroids: a possible treatment of asthma exacerbations.

UNLABELLED: Recovery from an asthma exacerbation may take days or weeks even after the introduction of appropriate exacerbation therapy. However airway responsiveness and sputum eosinophils can be reduced within 6 hours by a single dose of inhaled corticosteroids. AIM: To determine if a single dose of 3200 microg of budesonide increases the rate of recovery from an asthma exacerbation. METHODS: Nineteen asthmatic subjects with an asthma exacerbation following withdrawal of inhaled corticosteroids were randomised to receive either usual care (doubling their dose of inhaled corticosteroids) plus placebo or usual care plus a single dose of 3200 microg of budesonide in a double-blind manner. Subjects monitored peak flow (PEF), symptoms, and beta agonist use daily for four weeks. The lowest PEF reading for each week was calculated as a percentage of the best peak flow value achieved in the recent past (PEF lowest % best). RESULTS: In the first week following exacerbation, PEF (lowest % best) was significantly greater in the budesonide group than in the placebo group (87.4 +/- 4.7 vs. 76.7 +/- 5.3; p = 0.029). However in the fourth week following exacerbation PEF was not significantly different (p = 0.728). The proportion of subjects who had a symptom free day during the first week was significantly higher in the budesonide group (p = 0.0012). CONCLUSION: A single high dose of inhaled corticosteroids added to usual exacerbation treatment might increase the rate of recovery from a mild exacerbation of asthma.