COPD Prevalence and Risk Factors Among Saudi Adults Over 18 in Taif

This observational, cross-sectional study examines chronic obstructive pulmonary disease (COPD) and associated demographic, clinical, behavioral, and environmental factors among Saudi adults residing in Taif City, Saudi Arabia. The study addresses limited local evidence concerning COPD in a high-altitude setting, with particular attention to exposures beyond tobacco smoking.

The protocol describes recruitment from community settings and major hospitals in Taif using systematic sampling, selecting every tenth eligible individual from hospital records and community registries. Information is collected through participant surveys and available medical records. Data include demographic characteristics, previous COPD diagnosis, respiratory symptoms, smoking history, secondhand smoke exposure, occupational hazards, indoor pollutants, biofuel and incense use, socioeconomic circumstances, and relevant respiratory medical history.

COPD status is based on a reported or documented previous clinical diagnosis. Spirometric confirmation is not incorporated into the survey; therefore, the study estimates the prevalence of previously diagnosed COPD and may not identify undiagnosed airflow obstruction.

Symptom burden is assessed using the eight-item COPD Assessment Test (CAT). Its domains include cough, sputum production, chest tightness, exertional breathlessness, limitations in daily activities, confidence leaving home, sleep, and energy. Each item is scored from 0 to 5, producing a total score from 0 to 40, with higher scores indicating greater symptom burden. The questionnaire is used to assess symptoms rather than establish a COPD diagnosis.

The minimum sample size was calculated using an assumed prevalence of 50%, a 95% confidence level, and a margin of error of 5%, yielding approximately 384 participants. The uploaded manuscript reports a final sample of 777 participants.

The statistical analysis uses SPSS version 26. Descriptive statistics summarize participant characteristics and exposures. Prevalence estimates are calculated with 95% confidence intervals. Associations between categorical variables and COPD status are examined using chi-square tests. Differences in symptom scores between groups are assessed using independent-samples t-tests and one-way analysis of variance. Statistical significance is defined as a p-value below 0.05. Because the study is cross-sectional, observed associations cannot establish causation.

The protocol specifies written informed consent before participation and confidential handling of personal information, with collected data used solely for research purposes.