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EXHALED CARBON MONOXIDE LEVELS AMONG TOBACCO SMOKERS BY AGE
Summary
Exhaled carbon monoxide (ECO) can confirm tobacco smoking in Thailand. The optimal ECO cutoff level to detect smoking varies by age, with 4 ppm for younger adults and 5 ppm for older adults.
Area of Science:
- Public Health
- Biomedical Science
- Respiratory Medicine
Background:
- Exhaled carbon monoxide (ECO) measurement is a validated method for confirming tobacco smoking status.
- Limited data exists on ECO levels among Thai tobacco smokers, particularly concerning age-specific variations.
- Establishing accurate ECO cutoff levels is crucial for smoking cessation programs and public health interventions in Thailand.
Purpose of the Study:
- To determine the optimal ECO cutoff level for confirming tobacco smoking among Thai individuals.
- To assess whether this ECO cutoff level differs across various age groups.
- To provide age-stratified ECO thresholds for more precise smoking status verification in the Thai population.
Main Methods:
- A cross-sectional study involving 875 Thai volunteers (584 non-smokers, 291 smokers) aged 16-70 years was conducted in 2009.
- Participants were recruited from Pathum Thani and Khon Kaen provinces, central and northeastern Thailand, respectively.
- Exhaled carbon monoxide (ECO) levels were measured, and subjects underwent interviews to ascertain smoking status.
Main Results:
- The mean ECO level was significantly higher in smokers (11.24 ppm) compared to non-smokers (2.25 ppm).
- An overall ECO cutoff level of 5 ppm demonstrated good accuracy in distinguishing smokers from non-smokers (sensitivity 79.0%, specificity 89.9%).
- Age-specific optimal cutoff levels were identified: 4 ppm for ages 16-25 years (sensitivity 85.2%, specificity 77.5%) and 5 ppm for ages 26-70 years (sensitivity 79.4%, specificity 91.2%).
Conclusions:
- The optimal exhaled carbon monoxide (ECO) cutoff level for confirming tobacco smoking in Thai subjects is 5 ppm overall.
- Age-specific ECO cutoff levels (4 ppm for 16-25 years, 5 ppm for 26-70 years) improve the accuracy of smoking status determination.
- Implementing these age-adjusted ECO thresholds can enhance the reliability of smoking verification in public health initiatives targeting Thai populations.
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