Differentiating COPD from asthma in clinical practice

Potential of Health and Demographic Surveillance System in Asthma and Chronic Obstructive Pulmonary Disease Microbiome Research

Health and demographic surveillance system (HDSS) is a population-based health and vital event registration system that monitors demographic and health events in a geographically defined population at regular intervals. Human microbiome research in the past decade has been the field of increasingly intense research much due to its demonstrated impact upon various health conditions including human chronic airway diseases such as asthma and chronic obstructive pulmonary disease (COPD). Many confounding factors have been revealed to play a role in shaping the microbiome in chronic airway diseases. Asthma and COPD follows a typical pattern of disease progression, which includes stable and exacerbation state in which the microbiota is known to vary. However, many such studies lack extensive and longitudinal sampling with inadequate metadata, which has resulted in the inconsistencies in the observations. HDSS provides such a platform, which can offer a deeper understanding of the role of the microbiome in human health. In this review, we highlight opportunities and limitations in microbiome research with the help of studies conducted on chronic airway diseases like asthma and COPD. In addition, we also emphasize on the benefits of HDSS and future directions in lung microbiome research.

Asthma and COPD: Similarities and Differences in the Pathophysiology, Diagnosis and Therapy

Asthma and chronic obstructive pulmonary disease (COPD) are two of the most common chronic lung diseases worldwide. Distinguishing between these different pulmonary diseases can be difficult in practice because of symptomatic similarities. A definitive diagnosis is essential for correct treatment. This review article presents the different symptoms of these two chronic inflammatory lung diseases following a selective search of the PubMed database for relevant literature published between 1996 and 2012. While cough occurs in both diseases, asthmatics often have a dry cough mainly at night, which is often associated with allergies. In contrast, COPD is usually caused by years of smoking. Paroxysmal dyspnea, which occurs in asthma, is characterized by shortness of breath, while in COPD it occurs during physical exertion in early stages and at rest in later stages of the disease. Asthma often begins in childhood or adolescence, whereas COPD occurs mainly in smokers in later life. It is possible to live with asthma into old age, whereas the life expectancy of patients with COPD is significantly limited. Currently, there is no general curative treatment for either disorder.

Glucocorticoids and the Lung

The lung is a major clinical target of glucocorticoid-based therapeutics, and GR signaling has broad effects on respiratory physiology and inflammation. During lung development, expression of GR in the mesenchyme is required for normal terminal alveolar epithelial differentiation. Prenatal administration of exogenous glucocorticoids (GCs) to prevent neonatal respiratory distress syndrome, however, promotes alveolar maturation and accelerates surfactant expression in a manner consistent with direct effects on the developing alveolar epithelium. Likewise, cell autonomous effects of GCs in regulating gene expression and phenotype of the airway epithelium and airway smooth muscle have been demonstrated to control important therapeutic effects of GCs in treating asthma and chronic obstructive pulmonary disease. Here, mechanisms and consequences of GR signaling in the developing lung and in treating obstructive lung disease are reviewed, with a focus on direct effects of GR signaling on alveolar differentiation, surfactant expression, and airway epithelial and smooth muscle pathophysiology.

Optimizing chronic obstructive pulmonary disease management in primary care

Diagnosis of chronic obstructive pulmonary disease (COPD) in primary care is complex, as many clinical symptoms are similar to asthma and heart disease, which may lead to misdiagnosis and suboptimal disease management. Spirometry is the best method for diagnosing COPD and distinguishing between COPD, asthma, and cardiovascular diseases. Airway obstruction is fully reversible in asthma, but not in COPD, and can be confirmed when the postbronchodilator ratio of forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) is <0.7. Knowledge of COPD treatment guidelines and a proactive attitude toward disease management by primary care physicians are key to improving symptom control and patients' quality of life. Identification of the appropriate drug/inhaler combination, patient education, training on inhaler use followed by regular monitoring, and pulmonary rehabilitation are also vital to successful COPD management. This review outlines steps to aid physicians in devising and implementing an optimal management plan for COPD patients.

Improving the differential diagnosis of chronic obstructive pulmonary disease in primary care

Chronic obstructive pulmonary disease (COPD) and asthma represent a substantial portion of primary care practice. In adults, differentiating asthma from COPD can be difficult but is important because of the marked differences in treatment, disease progression, and outcomes between the 2 conditions. Currently, clinical COPD is often misdiagnosed or undiagnosed until late in the disease. Earlier diagnosis could markedly reduce morbidity and improve quality of life. Establishing a diagnosis of COPD requires spirometry testing, interpreted in the context of the patient's symptoms, smoking status, age, and comorbidities. Additional tests and tools may be helpful in the differential diagnosis, including questionnaires specifically developed to discriminate between COPD and asthma and, in special cases, imaging studies. Follow-up and monitoring of asthma and COPD are always necessary and provide additional benefit in patients in whom only continued care and reassessment can confirm the final diagnosis, such as younger individuals with fixed airway obstruction, smokers with asthma, and patients with both disorders. Key areas for improvement include enhanced case identification, improved quality and interpretation of findings on spirometry, and increased use of tools such as differential diagnosis questionnaires and algorithms to guide the diagnostic and monitoring process. To achieve optimal outcomes, the primary care team should make every effort to establish a firm diagnosis. For this review, we conducted a PubMed search with no time limits using the Medical Subject Headings chronic obstructive pulmonary disease or COPD and asthma, in association with the following search terms: diagnosis, differential diagnosis, mixed or comorbid disease, diagnostic techniques, spirometry, questionnaires, and primary care.

Office management of COPD in primary care: a 2009 clinical update

Primary care physicians (PCPs) usually are the first to diagnose and care for patients with chronic obstructive pulmonary disease (COPD). This article discusses key teaching points of recently published guidelines for PCPs and the common challenges of treating COPD patients in a primary care setting, and clarifies common misconceptions. First, PCPs should choose one of the published screening tools to assess for COPD. Spirometry is a useful tool to confirm the diagnosis of COPD to distinguish COPD from asthma, to stage the disease for determining treatment, and it can help with smoking cessation efforts. Chest radiographs do not help to diagnose COPD but are useful to rule out other causes of dyspnea and cough. Differentiating COPD from asthma is important because it affects treatment decisions and prognosis. Second, the goals of COPD treatment are to relieve symptoms, improve exercise tolerance, prevent exacerbations, and improve quality (although not necessarily extend quantity) of life. Chronic obstructive pulmonary disease can be treated at any stage, and the treatments are adjusted in a stepwise approach based on disease severity. Third, as part of the long-term management of COPD, smoking cessation should be discussed at every visit, and inhaler technique should be reviewed at regular intervals. Chronic obstructive pulmonary disease patients should also receive the recommended influenza and pneumococcal vaccinations. Primary care physicians are in a unique position to identify COPD patients early, to implement primary and secondary preventive measures, and to provide care that addresses the full spectrum of COPD and its comorbidities.