Determinants of Oral Health Literacy Among Older Chinese Adults: A Path Analysis Based on Andersen's Behavioral Model.

Persistent respiratory symptoms and airflow limitation characterize chronic obstructive pulmonary disease (COPD).[] It is a progressive condition characterized by pulmonary and systemic inflammation, as well as numerous associated extrapulmonary complications.[] Lung function continues to decline with age, and exacerbations may become life-threatening, more frequent, and with complications.[] According to a study, the overall prevalence of COPD in people aged 40 years and older was 12.64% and 7.38% based on fixed ratio and lower limit for normal criteria, respectively. The most common stage of COPD was Stage II, with a prevalence of 50.46%.[] It is the second most prevalent cause of noncommunicable disease-related deaths after road traffic accidents in India, with the age-specific prevalence of COPD increasing rapidly after the age of 30 years.[] A wide range of comorbidities and risk factors are associated with the disease, including smoking, genetics, infections, malnutrition, ageing, asthma, occupational exposures, indoor and outdoor air pollutants, and low socioeconomic status.[] According to the World Health Organization, modifiable risk factors are strongly associated with increased mortality in asthma and COPD. These factors include tobacco smoking habits, indoor air pollution from biofuels, urban outdoor air pollution, occupational factors, exposure to respiratory allergens, and ambient particulate matter.[] A persistent productive cough is a common symptom of COPD. Patients with COPD most often present with their first acute exacerbation at an advanced stage. Symptoms typically do not occur until the forced expiratory volume in the first second (FEV1) is approximately 50% of the predicted standard value.[]