Table 5. Risk factors for COPD in HICs and in LMICs.
| Prevalence | ||
|---|---|---|
| Risk factor | HICs | LMICs |
| Cigarette smoke | High | Variable, ranging from low [31] to high according to the settings |
| Biomass fuel smoke | Low to nonexistent | High |
| Outdoor air pollution | High | High in urban areas (less regulation of traffic-related pollution than in HICs), low in rural areas |
| Occupational exposures | Low (better regulations and controls for workers) | Likely several-fold higher than in HICs because of fewer safety measures for workers |
| Pulmonary tuberculosis | Low | High |
| Lower respiratory tract infections in early childhood | Low | High |
| Poorly controlled asthma | Low | Higher than in HICs because of lack of access to both medical care and treatments [32] |
| Malnutrition | Low | High |
COPD, chronic obstructive pulmonary disease; HIC, high-income country; LMIC, low- and middle-income country.