Real-world walking cadence in people with COPD.

Introduction: The clinical validity of real-world walking cadence in people with COPD is unsettled. Our objective was to assess the levels, variability and association with clinically relevant COPD characteristics and outcomes of real-world walking cadence. Methods: We assessed walking cadence (steps per minute during walking bouts longer than 10 s) from 7 days' accelerometer data in 593 individuals with COPD from five European countries, and clinical and functional characteristics from validated questionnaires and standardised tests. Severe exacerbations during a 12-month follow-up were recorded from patient reports and medical registries. Results: Participants were mostly male (80%) and had mean±sd age of 68±8 years, post-bronchodilator forced expiratory volume in 1 s (FEV1) of 57±19% predicted and walked 6880±3926 steps·day-1. Mean walking cadence was 88±9 steps·min-1, followed a normal distribution and was highly stable within-person (intraclass correlation coefficient 0.92, 95% CI 0.90-0.93). After adjusting for age, sex, height and number of walking bouts in fractional polynomial or linear regressions, walking cadence was positively associated with FEV1, 6-min walk distance, physical activity (steps·day-1, time in moderate-to-vigorous physical activity, vector magnitude units, walking time, intensity during locomotion), physical activity experience and health-related quality of life and negatively associated with breathlessness and depression (all p<0.05). These associations remained after further adjustment for daily steps. In negative binomial regression adjusted for multiple confounders, walking cadence related to lower number of severe exacerbations during follow-up (incidence rate ratio 0.94 per step·min-1, 95% CI 0.91-0.99, p=0.009). Conclusions: Higher real-world walking cadence is associated with better COPD status and lower severe exacerbations risk, which makes it attractive as a future prognostic marker and clinical outcome.

The burden of severe asthma in sub-Saharan Africa: Findings from the African Severe Asthma Project.

Background: Severe asthma is associated with high morbidity, mortality, and health care utilization, but its burden in Africa is unknown. Objective: We sought to determine the burden (prevalence, mortality, and activity and work impairment) of severe asthma in 3 countries in East Africa: Uganda, Kenya, and Ethiopia. Methods: Using the American Thoracic Society/European Respiratory Society case definition of severe asthma, we analyzed for the prevalence of severe asthma (requiring Global Initiative for Asthma [GINA] steps 4-5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4-5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA-recommended medications. Asthma control was assessed by the asthma control questionnaire (ACQ). Results: Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% confidence interval [CI], 23.1-28.3) and 4.6% (95% CI, 3.5-6.0), respectively. Patients with severe asthma were (nonsevere vs severe vs severe refractory) older (39, 42, 45 years, P = .011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, P = .004), had lower forced expiratory volume in 1 second percentage (81%, 61%, 55.5%, P < .001), had lower quality of life score (129, 127 vs 121, P < .001), and had higher activity impairment (10%, 30%, 50%, P < .001). Factors independently associated with severe asthma were hypertension comorbidity; adjusted odds ratio 2.21 (1.10-4.47), P = .027, high bronchial hyperresponsiveness questionnaire score; adjusted odds ratio 2.16 (1.01-4.61), P = .047 and higher ACQ score at baseline 2.80 (1.55-5.08), P = .001. Conclusion: The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.

Engaging stakeholders to level up COPD care in LMICs: lessons learned from the "Breathe Well" programme in Brazil, China, Georgia, and North Macedonia.

BACKGROUND: Effective stakeholder engagement in health research is increasingly being recognised and promoted as an important pathway to closing the gap between knowledge production and its use in health systems. However, little is known about its process and impacts, particularly in low-and middle-income countries. This opinion piece draws on the stakeholder engagement experiences from a global health research programme on Chronic Obstructive Pulmonary Disease (COPD) led by clinician researchers in Brazil, China, Georgia and North Macedonia, and presents the process, outcomes and lessons learned. MAIN BODY: Each country team was supported with an overarching engagement protocol and mentored to develop a tailored plan. Patient involvement in research was previously limited in all countries, requiring intensive efforts through personal communication, meetings, advisory groups and social media. Accredited training programmes were effective incentives for participation from healthcare providers; and aligning research findings with competing policy priorities enabled interest and dialogue with decision-makers. The COVID-19 pandemic severely limited possibilities for planned engagement, although remote methods were used where possible. Planned and persistent engagement contributed to shared knowledge and commitment to change, including raised patient and public awareness about COPD, improved skills and practice of healthcare providers, increased interest and support from clinical leaders, and dialogue for integrating COPD services into national policy and practice. CONCLUSION: Stakeholder engagement enabled relevant local actors to produce and utilise knowledge for small wins such as improving day-to-day practice and for long-term goals of equitable access to COPD care. For it to be successful and sustained, stakeholder engagement needs to be valued and integrated throughout the research and knowledge generation process, complete with dedicated resources, contextualised and flexible planning, and commitment.

Improved health status of severe COPD patients after being included in an integrated primary care service: A prospective cohort study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a prevalent lung disease. It is assumed that severe patients will receive better treatment in specialised care centres but the prevalence of severe COPD in primary care is high. Integrated primary care services combine input from several sources and advice from pulmonologists to provide general practitioners with support needed to improve diagnosis and treatment of patients with COPD. OBJECTIVES: To evaluate patient-reported outcomes and costs of managing patients classified as GOLD D in an integrated primary care service over 12 months. METHODS: Patients were included in this 1-year prospective cohort study if they met the 2014 GOLD D criteria, were aged ≥ 40 years and gave written informed consent for this study. Recruitment took place through the patients' general practitioners. The primary outcome was health status, assessed with the Clinical COPD Questionnaire (CCQ) and COPD Assessment Test (CAT). Secondary outcomes included self-reported exacerbations, quality-adjusted life years and health(care)-related costs. RESULTS: Forty-nine patients were included. At baseline, the mean CAT score was 15.9 and the median CCQ score was 1.7. After 12 months, scores had improved by 2.3 (95% confidence interval, 0.8-3.7) and 0.4 (95% confidence interval, 0.2-0.7), respectively. Percentage of patients with ≥2 exacerbations in the past 12 months also decreased from baseline (77.6%) to 12 months (16.7%). Changes in mean quarterly costs were small. CONCLUSION: An integrated service for COPD based in primary care may improve the health status of patients with a large burden of disease while not increasing health care costs.

Validity and responsiveness of the Daily- and Clinical visit-PROactive Physical Activity in COPD (D-PPAC and C-PPAC) instruments.

BACKGROUND: The Daily-PROactive and Clinical visit-PROactive Physical Activity (D-PPAC and C-PPAC) instruments in chronic obstructive pulmonary disease (COPD) combines questionnaire with activity monitor data to measure patients' experience of physical activity. Their amount, difficulty and total scores range from 0 (worst) to 100 (best) but require further psychometric evaluation. OBJECTIVE: To test reliability, validity and responsiveness, and to define minimal important difference (MID), of the D-PPAC and C-PPAC instruments, in a large population of patients with stable COPD from diverse severities, settings and countries. METHODS: We used data from seven randomised controlled trials to evaluate D-PPAC and C-PPAC internal consistency and construct validity by sex, age groups, COPD severity, country and language as well as responsiveness to interventions, ability to detect change and MID. RESULTS: We included 1324 patients (mean (SD) age 66 (8) years, forced expiratory volume in 1 s 55 (17)% predicted). Scores covered almost the full range from 0 to 100, showed strong internal consistency after stratification and correlated as a priori hypothesised with dyspnoea, health-related quality of life and exercise capacity. Difficulty scores improved after pharmacological treatment and pulmonary rehabilitation, while amount scores improved after behavioural physical activity interventions. All scores were responsive to changes in self-reported physical activity experience (both worsening and improvement) and to the occurrence of COPD exacerbations during follow-up. The MID was estimated to 6 for amount and difficulty scores and 4 for total score. CONCLUSIONS: The D-PPAC and C-PPAC instruments are reliable and valid across diverse COPD populations and responsive to pharmacological and non-pharmacological interventions and changes in clinically relevant variables.

Patterns of Physical Activity Progression in Patients With COPD.

INTRODUCTION: Although mean physical activity in COPD patients declines by 400-500steps/day annually, it is unknown whether the natural progression is the same for all patients. We aimed to identify distinct physical activity progression patterns using a hypothesis-free approach and to assess their determinants. METHODS: We pooled data from two cohorts (usual care arm of Urban Training [NCT01897298] and PROactive initial validation [NCT01388218] studies) measuring physical activity at baseline and 12 months (Dynaport MoveMonitor). We identified clusters (patterns) of physical activity progression (based on levels and changes of steps/day) using k-means, and compared baseline sociodemographic, interpersonal, environmental, clinical and psychological characteristics across patterns. RESULTS: In 291 COPD patients (mean±SD 68±8 years, 81% male, FEV1 59±19%pred) we identified three distinct physical activity progression patterns: Inactive (n=173 [59%], baseline: 4621±1757 steps/day, 12-month change (Δ): -487±1201 steps/day), ActiveImprovers (n=49 [17%], baseline: 7727±3275 steps/day, Δ:+3378±2203 steps/day) and ActiveDecliners (n=69 [24%], baseline: 11 267±3009 steps/day, Δ: -2217±2085 steps/day). After adjustment in a mixed multinomial logistic regression model using Active Decliners as reference pattern, a lower 6-min walking distance (RRR [95% CI] 0.94 [0.90-0.98] per 10m, P=.001) and a higher mMRC dyspnea score (1.71 [1.12-2.60] per 1 point, P=.012) were independently related with being Inactive. No baseline variable was independently associated with being an Active Improver. CONCLUSIONS: The natural progression in physical activity over time in COPD patients is heterogeneous. While Inactive patients relate to worse scores for clinical COPD characteristics, Active Improvers and Decliners cannot be predicted at baseline.

Publisher Correction: Implementing a context-driven awareness programme addressing household air pollution and tobacco: a FRESH AIR study.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Implementing a context-driven awareness programme addressing household air pollution and tobacco: a FRESH AIR study.

Most patients with chronic respiratory disease live in low-resource settings, where evidence is scarcest. In Kyrgyzstan and Vietnam, we studied the implementation of a Ugandan programme empowering communities to take action against biomass and tobacco smoke. Together with local stakeholders, we co-created a train-the-trainer implementation design and integrated the programme into existing local health infrastructures. Feasibility and acceptability, evaluated by the modified Conceptual Framework for Implementation Fidelity, were high: we reached ~15,000 Kyrgyz and ~10,000 Vietnamese citizens within budget (~€11,000/country). The right engaged stakeholders, high compatibility with local contexts and flexibility facilitated programme success. Scores on lung health awareness questionnaires increased significantly to an excellent level among all target groups. Behaviour change was moderately successful in Vietnam and highly successful in Kyrgyzstan. We conclude that contextualising the awareness programme to diverse low-resource settings can be feasible, acceptable and effective, and increase its sustainability. This paper provides guidance to translate lung health interventions to new contexts globally.

Skin prick reactivity among asthmatics in East Africa.

BACKGROUND: The burden of asthma in Africa is high, and yet the disease is not universally prioritised. Data on allergic asthma and its impact on asthma morbidity are limited in Africa. Our aim was to describe the distribution of skin prick positivity among asthmatics in Eastern Africa. METHODS: From August 2016 to May 2018, 1671 asthmatic patients were enrolled from Uganda, Kenya, and Ethiopia as part of the African Severe Asthma Program clinical study. Skin prick testing was performed at baseline using a panel of 12 allergens, and factors associated with skin prick reactivity determined. RESULTS: Of the 1, 671 patients recruited, 71% were female with a median age of 40 years, 93.6% were aged >15 years and the patterns of asthma symptom frequency was intermittent in 2.9%, mild persistent in 19.9%, moderate persistent in 42.6% and severe persistent in 34.6% at baseline. Self-reported triggers, were dust (92%), cold weather (89%), upper respiratory infections (84%), strong smells (79%) and exposure to tobacco (78%). The majority (90%) of the participants had at least 1 positive allergen reaction, with 0.9% participants reacting to all the 12 allergens. Participants commonly reacted to house dust mites (66%), Blomia tropicalis (62%), and the German cockroach (52%). Patients sensitized to more allergens (>2) had significantly reduced lung function (FEV ≤ 80%; p = 0.001) and were more likely to visit the emergency department due to asthma (p = 0.012). There was no significant relationship between number of allergens and measures of asthma control, quality of life, and other clinical outcomes. Only the country of origin was independently associated with atopy among African asthmatics. CONCLUSION: There is a high prevalence of skin prick positivity among East African patients with asthma, with the commonest allergen being house dust mite. Skin reactivity did not correlate well with asthma severity and poor asthma control. The relation between atopy, measured through skin prick testing, and measures of asthma control among asthma patients in Eastern Africa is unclear and needs further study. TRIAL REGISTRATION: The ASAP study was registered prospectively. ClinicalTrials.gov Identifier: NCT03065920; Registration date: February 28, 2017; Last verified: February 28, 2017.

Phenotypic characteristics and asthma severity in an East African cohort of adults and adolescents with asthma: findings from the African severe asthma project.

RATIONALE: The relationship between clinical and biomarker characteristics of asthma and its severity in Africa is not well known. METHODS: Using the Expert Panel Report 3, we assessed for asthma severity and its relationship with key phenotypic characteristics in Uganda, Kenya and Ethiopia. The characteristics included adult onset asthma, family history of asthma, exposures (smoking and biomass), comorbidities (HIV, hypertension, obesity, tuberculosis (TB), rhinosinusitis, gastro-oesophageal disease (GERD) and biomarkers (fractional exhaled nitric oxide (FeNO), skin prick test (SPT) and blood eosinophils). We compared these characteristics on the basis of severity and fitted a multivariable logistic regression model to assess the independent association of these characteristics with asthma severity. RESULTS: A total of 1671 patients were enrolled, 70.7% women, with median age of 40 years. The prevalence of intermittent, mild persistent, moderate persistent and severe persistent asthma was 2.9%, 19.9%, 42.6% and 34.6%, respectively. Only 14% were on inhaled corticosteroids (ICS). Patients with severe persistent asthma had a higher rate of adult onset asthma, smoking, HIV, history of TB, FeNO and absolute eosinophil count but lower rates of GERD, rhinosinusitis and SPT positivity. In the multivariate model, Ethiopian site and a history of GERD remained associated with asthma severity. DISCUSSION: The majority of patients in this cohort presented with moderate to severe persistent asthma and the use of ICS was very low. Improving access to ICS and other inhaled therapies could greatly reduce asthma morbidity in Africa.

Effects and acceptability of implementing improved cookstoves and heaters to reduce household air pollution: a FRESH AIR study.

The objective was to evaluate the effectiveness and acceptability of locally tailored implementation of improved cookstoves/heaters in low- and middle-income countries. This interventional implementation study among 649 adults and children living in rural communities in Uganda, Vietnam and Kyrgyzstan, was performed after situational analyses and awareness programmes. Outcomes included household air pollution (PM2.5 and CO), self-reported respiratory symptoms (with CCQ and MRC-breathlessness scale), chest infections, school absence and intervention acceptability. Measurements were conducted at baseline, 2 and 6-12 months after implementing improved cookstoves/heaters. Mean PM2.5 values decrease by 31% (to 95.1 µg/m3) in Uganda (95%CI 71.5-126.6), by 32% (to 31.1 µg/m3) in Vietnam (95%CI 24.5-39.5) and by 65% (to 32.4 µg/m3) in Kyrgyzstan (95%CI 25.7-40.8), but all remain above the WHO guidelines. CO-levels remain below the WHO guidelines. After intervention, symptoms and infections diminish significantly in Uganda and Kyrgyzstan, and to a smaller extent in Vietnam. Quantitative assessment indicates high acceptance of the new cookstoves/heaters. In conclusion, locally tailored implementation of improved cookstoves/heaters is acceptable and has considerable effects on respiratory symptoms and indoor pollution, yet mean PM2.5 levels remain above WHO recommendations.

Baseline health status and setting impacted minimal clinically important differences in COPD: an exploratory study.

OBJECTIVES: Minimal clinically important differences (MCIDs) are used as fixed numbers in the interpretation of clinical trials. Little is known about its dynamics. This study aims to explore the impact of baseline score, study setting, and patient characteristics on health status MCIDs in chronic obstructive pulmonary disease (COPD). STUDY DESIGN AND SETTING: Baseline and follow-up data on the COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ), and St. George's Respiratory Questionnaire (SGRQ) were retrospectively analyzed from pulmonary rehabilitation (PR) and routine clinical practice (RCP). Anchor- and distribution-based MCID estimates were calculated and tested between settings, gender, age, Global initiative for Obstructive Lung Disease (GOLD) classification, comorbidities, and baseline health status. RESULTS: In total, 658 patients were included with 2,299 change score measurements. MCID estimates for improvement and deterioration ranged for all subgroups 0.50-6.30 (CAT), 0.10-0.84 (CCQ), and 0.33-12.86 (SGRQ). Larger MCID estimates for improvement and smaller ones for deterioration were noted in patients with worse baseline health status, females, elderly, GOLD I/II patients, and patients with less comorbidities. Estimates from PR were larger. CONCLUSION: Baseline health status and setting affected MCID estimates of COPD health status questionnaires. Patterns were observed for gender, age, spirometry classification, and comorbidity levels. These outcomes would advocate the need for tailored MCIDs.

Thresholds for clinically important deterioration versus improvement in COPD health status: results from a randomised controlled trial in pulmonary rehabilitation and an observational study during routine clinical practice.

OBJECTIVES: Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease. Preventing deterioration of health status is therefore an important therapy goal. (Minimal) Clinically Important Differences ((M)CIDs) are used to interpret changes observed. It remains unclear whether (M)CIDs are similar for both deterioration and improvement in health status. This study investigates and compares these clinical thresholds for three widely-used questionnaires. DESIGN AND SETTING: Data were retrospectively analysed from an inhouse 3-week pulmonary rehabilitation (PR) randomised controlled trial in the German Klinik Bad Reichenhall (study 1), and observational research in Dutch primary and secondary routine clinical practice (RCP) (study 2). PARTICIPANTS: Patients with COPD aged ≥18 years (study 1) and aged ≥40 years (study 2) without respiratory comorbidities were included for analysis. PRIMARY OUTCOMES: The COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ) and St George's Respiratory Questionnaire (SGRQ) were completed at baseline and at 3, 6 and 12 months. A Global Rating of Change scale was added at follow-up. Anchor-based and distribution-based methods were used to determine clinically relevant thresholds. RESULTS: In total, 451 patients were included from PR and 207 from RCP. MCIDs for deterioration ranged from 1.30 to 4.21 (CAT), from 0.19 to 0.66 (CCQ), and from 2.75 to 7.53 (SGRQ). MCIDs for improvement ranged from -3.78 to -1.53 (CAT), from -0.50 to -0.19 (CCQ), and from -9.20 to -2.76 (SGRQ). Thresholds for moderate improvement versus deterioration ranged from -5.02 to -3.29 vs 3.89 to 8.14 (CAT), from -0.90 to -0.72 vs 0.42 to 1.23 (CCQ), and from -15.85 to -13.63 vs 7.46 to 9.30 (SGRQ). CONCLUSIONS: MCID ranges for improvement and deterioration on the CAT, CCQ and SGRQ were somewhat similar. However, estimates for moderate and large change varied and were inconsistent. Thresholds differed between study settings. TRIAL REGISTRATION NUMBER: Routine Inspiratory Muscle Training within COPD Rehabilitation trial: #DRKS00004609; MCID study: #UMCG201500447.

Prevalence and factors associated with asthma among adolescents and adults in Uganda: a general population based survey.

BACKGROUND: Recent large-scale population data on the prevalence of asthma and its risk factors are lacking in Uganda. This survey was conducted to address this data gap. METHODS: A general population based survey was conducted among people ≥12 years. A questionnaire was used to collect participants socio-demographics, respiratory symptoms, medical history, and known asthma risk factors. Participants who reported wheeze in the past 12 months, a physician diagnosis of asthma or current use of asthma medications were classified as having asthma. Asthmatics who were ≥ 35 years underwent spirometry to determine how many had fixed airflow obstruction (i.e. post bronchodilator forced expiratory volume in one second/forced vital capacity (FEV1/FVC) ratio < lower limit of normal (LLN). Descriptive statistics were used to summarize participants' characteristics. Prevalence of asthma was calculated as a proportion of asthmatics over total survey population. To obtain factors independently associated with asthma, a random-effects model was fitted to the data. RESULTS: Of the 3416 participants surveyed, 61.2% (2088) were female, median age was 30 years (IQR, 20-45) and 323 were found to have asthma. Sixteen people with asthma ≥35 years had fixed airflow obstruction. The prevalence of asthma was 11.0% (95% CI:8.9-13.2; males 10.3%, females 11.4%, urban 13.0% and rural 8.9%. Significantly more people with asthma smoked than non-asthmatics: 14.2% vs. 6.3%, p < 0.001, were exposed to biomass smoke: 28.0% vs. 20.0%, p < 0.001, had family history of asthma: 26.9% vs. 9.4%, p, < 0.001, had history of TB: 3.1% vs. 1.30%, p = 0.01, and had hypertension: 17.9% vs. 12.0%, p = 0. 003. In multivariate analysis smoking, (adjusted odds ratio (AOR), 3.26 (1.96-5.41, p < 0.001) family history of asthma, AOR 2.90 (98-4.22 p- < 0.001), nasal congestion, AOR 3.56 (2.51-5.06, p < 0.001), biomass smoke exposure, AOR 2.04 (1.29-3.21, p = 0.002) and urban residence, AOR 2.01(1.23-3.27, p = 0.005) were independently associated with asthma. CONCLUSION: Asthma is common in Uganda and is associated with smoking, biomass smoke exposure, urbanization, and allergic diseases. Health care systems should be strengthened to provide asthma care. Measures to reduce exposure to the identified associated factors are needed.

Smartphone-Based Physical Activity Telecoaching in Chronic Obstructive Pulmonary Disease: Mixed-Methods Study on Patient Experiences and Lessons for Implementation.

BACKGROUND: Telecoaching approaches can enhance physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD). However, their effectiveness is likely to be influenced by intervention-specific characteristics. OBJECTIVE: This study aimed to assess the acceptability, actual usage, and feasibility of a complex PA telecoaching intervention from both patient and coach perspectives and link these to the effectiveness of the intervention. METHODS: We conducted a mixed-methods study based on the completers of the intervention group (N=159) included in an (effective) 12-week PA telecoaching intervention. This semiautomated telecoaching intervention consisted of a step counter and a smartphone app. Data from a project-tailored questionnaire (quantitative data) were combined with data from patient interviews and a coach focus group (qualitative data) to investigate patient and coach acceptability, actual usage, and feasibility of the intervention. The degree of actual usage of the smartphone and step counter was also derived from app data. Both actual usage and perception of feasibility were linked to objectively measured change in PA. RESULTS: The intervention was well accepted and perceived as feasible by all coaches present in the focus group as well by patients, with 89.3% (142/159) of patients indicating that they enjoyed taking part. Only a minority of patients (8.2%; 13/159) reported that they found it difficult to use the smartphone. Actual usage of the step counter was excellent, with patients wearing it for a median (25th-75th percentiles) of 6.3 (5.8-6.8) days per week, which did not change over time (P=.98). The smartphone interface was used less frequently and actual usage of all daily tasks decreased significantly over time (P<.001). Patients needing more contact time had a smaller increase in PA, with mean (SD) of +193 (SD 2375) steps per day, +907 (SD 2306) steps per day, and +1489 (SD 2310) steps per day in high, medium, and low contact time groups, respectively; P for-trend=.01. The overall actual usage of the different components of the intervention was not associated with change in step count in the total group (P=.63). CONCLUSIONS: The 12-week semiautomated PA telecoaching intervention was well accepted and feasible for patients with COPD and their coaches. The actual usage of the step counter was excellent, whereas actual usage of the smartphone tasks was lower and decreased over time. Patients who required more contact experienced less PA benefits. TRIAL REGISTRATION: ClinicalTrials.gov NCT02158065; http://clinicaltrials.gov/ct2/show/NCT02158065 (Archived by WebCite at http://www.webcitation.org/73bsaudy9).

Lung Function of Children at Three Sites of Varying Ambient Air Pollution Levels in Uganda: A Cross Sectional Comparative Study.

Air pollution is a major cause of sub-optimal lung function and lung diseases in childhood and adulthood. In this study we compared the lung function (measured by spirometry) of 537 Ugandan children, mean age 11.1 years in sites with high (Kampala and Jinja) and low (Buwenge) ambient air pollution levels, based on the concentrations of particulate matter smaller than 2.5 micrometres in diameter (PM2.5). Factors associated with lung function were explored in a multiple linear regression model. PM2.5 level in Kampala, Jinja and Buwenge were 177.5 µg/m³, 96.3 µg/m³ and 31.4 µg/m³ respectively (p = 0.0000). Respectively mean forced vital capacity as % of predicted (FVC%), forced expiratory volume in one second as % of predicted (FEV1%) and forced expiratory flow 25⁻75% as % of predicted (FEF25⁻75%) of children in high ambient air pollution sites (Kampala and Jinja) vs. those in the low ambient air pollution site (Buwenge subcounty) were: FVC% (101.4%, vs. 104.0%, p = 0.043), FEV1% (93.9% vs. 98.0, p = 0.001) and FEF25⁻75% (87.8 vs. 94.0, p = 0.002). The proportions of children whose %predicted parameters were less than 80% predicted (abnormal) were higher among children living in high ambient air pollution than those living in lower low ambient air pollutions areas with the exception of FVC%; high vs. low: FEV1 < 80%, %predicted (12.0% vs. 5.3%, p = 0.021) and FEF25⁻75 < 80%, %predicted (37.7% vs. 29.3%, p = 0.052) Factors associated with lung function were (coefficient, p-value): FVC% urban residence (-3.87, p = 0.004), current cough (-2.65, p = 0.048), underweight (-6.62, p = 0.000), and overweight (11.15, p = 0.000); FEV1% underweight (-6.54, p = 0.000) and FEF25⁻75% urban residence (-8.67, p = 0.030) and exposure to biomass smoke (-7.48, p = 0.027). Children in study sites with high ambient air pollution had lower lung function than those in sites with low ambient air pollution. Urban residence, underweight, exposure to biomass smoke and cough were associated with lower lung function.

The impact of HIV on the prevalence of asthma in Uganda: a general population survey.

BACKGROUND: HIV and asthma are highly prevalent diseases in Africa but few studies have assessed the impact of HIV on asthma prevalence in high HIV burden settings. The objective of this analysis was to compare the prevalence of asthma among persons living with HIV (PLHIV) and those without HIV participating in the Uganda National Asthma Survey (UNAS). METHODS: UNAS was a population-based survey of persons aged ≥12 years. Asthma was diagnosed based on either self-reported current wheeze concurrently or within the prior 12 months; physician diagnosis; or use of asthma medication. HIV was defined based on confidential self-report. We used Poisson regression with robust standard errors to estimate asthma prevalence and the prevalence ratio (PR) for HIV and asthma. RESULTS: Of 3416 participants, 2067 (60.5%) knew their HIV status and 103 (5.0%) were PLHIV. Asthma prevalence was 15.5% among PLHIV and 9.1% among those without HIV, PR 1.72, (95%CI 1.07-2.75, p = 0.025). HIV modified the association of asthma with the following factors, PLHIV vs. not PLHIV: tobacco smoking (12% vs. 8%, p = < 0.001), biomass use (11% vs. 7%, p = < 0.001), allergy (17% vs. 11%, p = < 0.001), family history of asthma (17% vs. 11%, p = < 0.001), and prior TB treatment (15% vs. 10%, p = < 0.001). CONCLUSION: In Uganda the prevalence of asthma is higher in PLHIV than in those without HIV, and HIV interacts synergistically with other known asthma risk factors. Additional studies should explore the mechanisms underlying these associations. Clinicians should consider asthma as a possible diagnosis in PLHIV presenting with respiratory symptoms.

Clinically relevant differences in COPD health status: systematic review and triangulation.

The minimal clinically important difference (MCID) quantifies when measured differences can be considered clinically relevant. This study aims to review and triangulate MCIDs of chronic obstructive pulmonary disease (COPD) health status tools.A systematic search in PubMed, EMBASE and Cochrane Library was conducted (Prospero #CRD42015023221). Study details, patient characteristics, MCID methodology and estimates were assessed and extracted by two authors. A triangulated mean was obtained for each tool's MCID, with two-thirds weighting for anchor-based and one-third for distribution-based results. This was then multiplied by a weighted factor based upon the study size and quality rating.Overall, 785 records were reviewed of which 21 studies were included for analysis. MCIDs of 12 tools were presented. General quality and risk of bias were average to good. Triangulated MCIDs for the COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ) and St. George's Respiratory Questionnaire (SGRQ) were -2.54, -0.43 and -7.43 for improvement. Too few and/or too diverse studies were present to triangulate MCIDs of other tools.Evidence for the MCID of the CAT and CCQ was strong and triangulation was valid. Currently used MCIDs in clinical practice for the SGRQ (4) and Chronic Respiratory Questionnaire (0.5) did not match the reviewed content, for which the MCIDs were much higher. Using too low MCIDs may lead to an overestimation of the interpretation of treatment effects. MCIDs for deterioration were scarce, which highlights the need for more research.