Validation of Noninvasive Assessment of Pulmonary Gas Exchange in Patients with Chronic Obstructive Pulmonary Disease during Initial Exposure to High Altitude.

Investigation of pulmonary gas exchange efficacy usually requires arterial blood gas analysis (aBGA) to determine arterial partial pressure of oxygen (mPaO2) and compute the Riley alveolar-to-arterial oxygen difference (A-aDO2); that is a demanding and invasive procedure. A noninvasive approach (AGM100), allowing the calculation of PaO2 (cPaO2) derived from pulse oximetry (SpO2), has been developed, but this has not been validated in a large cohort of chronic obstructive pulmonary disease (COPD) patients. Our aim was to conduct a validation study of the AG100 in hypoxemic moderate-to-severe COPD. Concurrent measurements of cPaO2 (AGM100) and mPaO2 (EPOC, portable aBGA device) were performed in 131 moderate-to-severe COPD patients (mean ±SD FEV1: 60 ± 10% of predicted value) and low-altitude residents, becoming hypoxemic (i.e., SpO2 < 94%) during a short stay at 3100 m (Too-Ashu, Kyrgyzstan). Agreements between cPaO2 (AGM100) and mPaO2 (EPOC) and between the O2-deficit (calculated as the difference between end-tidal pressure of O2 and cPaO2 by the AGM100) and Riley A-aDO2 were assessed. Mean bias (±SD) between cPaO2 and mPaO2 was 2.0 ± 4.6 mmHg (95% Confidence Interval (CI): 1.2 to 2.8 mmHg) with 95% limits of agreement (LoA): -7.1 to 11.1 mmHg. In multivariable analysis, larger body mass index (p = 0.046), an increase in SpO2 (p < 0.001), and an increase in PaCO2-PETCO2 difference (p < 0.001) were associated with imprecision (i.e., the discrepancy between cPaO2 and mPaO2). The positive predictive value of cPaO2 to detect severe hypoxemia (i.e., PaO2 ≤ 55 mmHg) was 0.94 (95% CI: 0.87 to 0.98) with a positive likelihood ratio of 3.77 (95% CI: 1.71 to 8.33). The mean bias between O2-deficit and A-aDO2 was 6.2 ± 5.5 mmHg (95% CI: 5.3 to 7.2 mmHg; 95%LoA: -4.5 to 17.0 mmHg). AGM100 provided an accurate estimate of PaO2 in hypoxemic patients with COPD, but the precision for individual values was modest. This device is promising for noninvasive assessment of pulmonary gas exchange efficacy in COPD patients.

Medication availability and economic barriers to adherence in asthma and COPD patients in low-resource settings.

Inhaled medication is essential to control asthma and COPD, but availability and proper adherence are challenges in low-middle income countries (LMIC). Data on medication availability and adherence in Central Asia are lacking. We aimed to investigate the availability of respiratory medication and the extent of financially driven non-adherence in patients with COPD and asthma in Kyrgyzstan. A cross-sectional study was conducted in two regions of Kyrgyzstan. Patients with a physician- and spirometry confirmed diagnosis of asthma and/or COPD were included. The main outcomes were (1) availability of respiratory medication in hospitals and pharmacies, assessed by a survey, and (2) medication adherence, assessed by the Test of Adherence to Inhalers (TAI). Logistic regression analyses were used to identify predictors for adherence. Of the 300 participants (COPD: 264; asthma: 36), 68.9% were buying respiratory medication out-of-pocket. Of all patients visiting the hospital, almost half reported medication not being available. In pharmacies, this was 8%. Poor adherence prevailed over intermediate and good adherence (80.7% vs. 12.0% and 7.3%, respectively). Deliberate and erratic non-adherence behavior patterns were the most frequent (89.7% and 88.0%), followed by an unconscious non-adherent behavioral pattern (31.3%). In total, 68.3% reported a financial reason as a barrier to proper adherence. Low BMI was the only factor significantly associated with good adherence. In this LMIC population, poor medication availability was common and 80% were poorly adherent. Erratic and deliberate non-adherent behaviors were the most common pattern and financial barriers play a role in over two-thirds of the population.

Clinical Characteristics, Treatment Patterns and Economic Burden of COPD in Kyrgyzstan: A FRESH AIR Study.

BACKGROUND: COPD prevalence and mortality in Kyrgyzstan are high. Data on clinical and economic impact of COPD in Kyrgyzstan are scarce. This study was part of the FRESH AIR research project that focused on prevention, diagnosis and treatment of chronic lung diseases in low-resource settings. AIM: We aimed to evaluate the clinical characteristics, treatment patterns and economic burden of COPD in Kyrgyzstan. METHODS: A representative sample of patients with a spirometry-confirmed diagnosis of COPD was included. All patients were registered in one of the five major hospitals in Kyrgyzstan. Patients were surveyed on COPD risk factors, health-care utilization and patient reported outcomes (CCQ, MRC). Associations with high symptom burden (MRC score ≥4) and cost were assessed using logistic regression analyses. RESULTS: A total of 306 patients were included with mean age 62.1 (SD: 11.2), 61.4% being male, mean BMI 26.9 (SD: 5.2) and mean monthly income $85.1 (SD: 75.4). Biomass was used for heating and cooking by 71.2% and 52.0%. Current and ex-smokers accounted 14.1% and 32%. Mean FEV1 was 46% (SD: 12.8), 71.9% had COPD GOLD III-IV and most frequent co-morbidities were hypertension (25.2%), diabetes (5.6%) and heart diseases (4.6%). Mean CCQ score was 2.0 (SD: 0.9) and MRC score 3.7 (SD: 0.9). Yearly mean number of hospital days due to COPD was 10.1 (SD: 3.9). Total annual per-patient costs of reimbursed health-care utilization ($107) and co-payments ($224, ie, 22% of patients' annual income) were $331. We found that only GOLD IV and hypertension were significantly associated with high symptom burden. Exacerbations and hypertension were significantly associated with high cost. CONCLUSION: The clinical and economic burden of COPD on patients and the government in Kyrgyzstan is considerable. Notably, almost half of interviewed patients were current or ex-smokers and biomass exposure was high.

Prevalence and Economic Burden of Respiratory Diseases in Central Asia and Russia: A Systematic Review.

Prevalence data of respiratory diseases (RDs) in Central Asia (CA) and Russia are contrasting. To inform future research needs and assist government and clinical policy on RDs, an up-to-date overview is required. We aimed to review the prevalence and economic burden of RDs in CA and Russia. PubMed and EMBASE databases were searched for studies that reported prevalence and/or economic burden of RDs (asthma, chronic obstructive pulmonary disease (COPD), cystic fibrosis, interstitial lung diseases (ILD), lung cancer, pulmonary hypertension, and tuberculosis (TB)) in CA (Kyrgyzstan, Uzbekistan, Tajikistan, Kazakhstan, and Turkmenistan) and Russia. A total of 25 articles (RD prevalence: 18; economics: 7) were included. The majority (n = 12), mostly from Russia, reported on TB. TB prevalence declined over the last 20 years, to less than 100 per 100,000 across Russia and CA, yet in those, multidrug-resistant tuberculosis (MDR-TB) was alarming high (newly treated: 19-26%, previously treated: 60-70%). COPD, asthma (2-15%) and ILD (0.006%) prevalence was only reported for Russia and Kazakhstan. No studies on cystic fibrosis, lung cancer and pulmonary hypertension were found. TB costs varied between US$400 (Tajikistan) and US$900 (Russia) for drug-susceptible TB to ≥US$10,000 for MDR-TB (Russia). Non-TB data were scarce and inconsistent. Especially in CA, more research into the prevalence and burden of RDs is needed.

The socioeconomic burden of chronic lung disease in low-resource settings across the globe - an observational FRESH AIR study.

BACKGROUND: Low-resource settings are disproportionally burdened by chronic lung disease due to early childhood disadvantages and indoor/outdoor air pollution. However, data on the socioeconomic impact of respiratory diseases in these settings are largely lacking. Therefore, we aimed to estimate the chronic lung disease-related socioeconomic burden in diverse low-resource settings across the globe. To inform governmental and health policy, we focused on work productivity and activity impairment and its modifiable clinical and environmental risk factors. METHODS: We performed a cross-sectional, observational FRESH AIR study in Uganda, Vietnam, Kyrgyzstan, and Greece. We assessed the chronic lung disease-related socioeconomic burden using validated questionnaires among spirometry-diagnosed COPD and/or asthma patients (total N = 1040). Predictors for a higher burden were studied using multivariable linear regression models including demographics (e.g. age, gender), health parameters (breathlessness, comorbidities), and risk factors for chronic lung disease (smoking, solid fuel use). We applied identical models per country, which we subsequently meta-analyzed. RESULTS: Employed patients reported a median [IQR] overall work impairment due to chronic lung disease of 30% [1.8-51.7] and decreased productivity (presenteeism) of 20.0% [0.0-40.0]. Remarkably, work time missed (absenteeism) was 0.0% [0.0-16.7]. The total population reported 40.0% [20.0-60.0] impairment in daily activities. Breathlessness severity (MRC-scale) (B = 8.92, 95%CI = 7.47-10.36), smoking (B = 5.97, 95%CI = 1.73-10.22), and solid fuel use (B = 3.94, 95%CI = 0.56-7.31) were potentially modifiable risk factors for impairment. CONCLUSIONS: In low-resource settings, chronic lung disease-related absenteeism is relatively low compared to the substantial presenteeism and activity impairment. Possibly, given the lack of social security systems, relatively few people take days off work at the expense of decreased productivity. Breathlessness (MRC-score), smoking, and solid fuel use are potentially modifiable predictors for higher impairment. Results warrant increased awareness, preventive actions and clinical management of lung diseases in low-resource settings from health policymakers and healthcare workers.

Diagnosis and treatment of acute respiratory illness in children under five in primary care in low-, middle-, and high-income countries: A descriptive FRESH AIR study.

BACKGROUND: Respiratory disease and, specifically, pneumonia, is the major cause of mortality and morbidity in young children. Diagnosis of both pneumonia and asthma in primary care rests principally on clinical signs, history taking, and bronchodilator responsiveness. This study aimed to describe clinical practices in diverse global primary care settings concerning differential diagnosis of respiratory disease in young children, especially between pneumonia and asthma. METHODS: Health professionals in Greece, Kyrgyzstan, Vietnam, and Uganda were observed during consultations with children aged 2-59 months, presenting with cough and/or difficult breathing. Data were analyzed descriptively and included consultation duration, practices, diagnoses and availability/use of medications and equipment. The study is part of the European Horizon 2020 FRESH AIR project. RESULTS: In total, 771 consultations by 127 health professionals at 74 facilities in the four countries were observed. Consultations were shorter in Vietnam and Uganda (3 to 4 minutes) compared to Greece and Kyrgyzstan (15 to 20 minutes). History taking was most comprehensive in Greece. Clinical examination was more comprehensive in Vietnam and Kyrgyzstan and less in Uganda. Viral upper respiratory tract infections were the most common diagnoses (41.7% to 67%). Pneumonia was diagnosed frequently in Uganda (16.3% of children), and rarely in other countries (0.8% to 2.9%). Asthma diagnosis was rare (0% to 2.8%). Antibiotics were prescribed frequently in all countries (32% to 69%). Short acting ß-agonist trials were seldom available and used during consultations in Kyrgyzstan (0%) and Uganda (1.8%), and often in Greece (38.9%) and Vietnam (12.6%). CONCLUSIONS: Duration and comprehensiveness of clinical consultations observed in this study seemed insufficient to guide respiratory diagnosis in young children. Appropriate treatment options may further not be available in certain studied settings. Actions aiming at educating and raising professional awareness, along with developing easy-to-use tools to support diagnosis and a general strengthening of health systems are important goals.