BACKGROUND: Time to first cigarette after waking is an indicator of nicotine dependence. We aimed to identify the association between time to first cigarette and spirometry-proven obstructive respiratory impairment, especially chronic obstructive pulmonary disease, in current smokers. METHODS: We included 392 subjects who visited the comprehensive medical examination center of Hallym University Sacred Heart Hospital between July 2014 and September 2015. Subjects with lung disease or anemia were excluded. Obstructive pulmonary impairment was defined as < 70% of the predicted value of forced expiratory volume in 1 second/forced vital capacity. Subjects were classified into the early (≤30 minutes) and late (>30 minutes) groups based on the time to first cigarette. Logistic regression and linear regression analyses were used for data analysis. RESULTS: Ninety-eight subjects (25%) were classified into the early group. After adjusting for smoking behaviors (cigarettes per day and smoking duration), socioeconomic status (education and income), age, and physical activity, an early time to first cigarette was found to be associated with an increased risk of obstructive pulmonary impairment measured using spirometry (adjusted odds ratio, 2.84; 95% confidence interval, 1.22–6.61). CONCLUSION: Compared to current smokers with a late time to first cigarette, those with an early time to first cigarette had a higher risk of obstructive pulmonary impairment, especially chronic obstructive pulmonary disease. Classifying smoking-related behaviors, especially time to first cigarette, may help target clinical screening for chronic obstructive pulmonary disease.
Anemia ; Forced Expiratory Volume ; Heart ; Linear Models ; Logistic Models ; Lung Diseases ; Mass Screening ; Motor Activity ; Odds Ratio ; Pulmonary Disease, Chronic Obstructive* ; Respiratory Function Tests ; Smoke ; Smoking ; Social Class ; Spirometry* ; Statistics as Topic ; Tobacco Products* ; Tobacco Use Disorder ; Vital Capacity

BACKGROUND: This study evaluated factors independently associated with electrocardiographic left ventricular hypertrophy (ECG-LVH) in subjects who were normotensive on clinical measurement and had no prior history of hypertension. METHODS: This cross-sectional study analyzed cases and controls in the Comprehensive Medical Examination Center of Hallym University Sacred Heart Hospital. Eligible case participants presented ECG-LVH according to the Sokolow- Lyon or Cornell criteria, were normotensive on clinical measurement, and had never received a diagnosis of hypertension. The control group comprised subjects with normal sinus rhythm who were normotensive on clinical measurement with no history of hypertension. RESULTS: A multiple logistic regression model showed male sex, age and systolic blood pressure to be positively related to the presence of ECG-LVH. A positive relation of smoking and regular exercise; an inverse relation of pulse rate to the presence of ECG-LVH were found only in men. An inverse relation of uric acid level was found only in women. Detailed analyses of relatively healthy and young men according to whether or not to exercise regularly showed that positive relations of age and systolic blood pressure; an inverse relation of obesity to the presence of ECG-LVH were apparent in the non-regular exercise group but not in the regular exercise group. In the regular exercise group, only pulse rate showed significant (inverse) association with the presence of ECG-LVH. CONCLUSION: The varying risk factor profiles associated with ECG-LVH according to sex and the participation in regular exercise may help to elucidate the ECG-LVH in clinical normotensives with no prior history of hypertension.
Blood Pressure ; Cardiovascular Diseases ; Cross-Sectional Studies ; Diagnosis ; Electrocardiography ; Female ; Heart ; Heart Rate ; Humans ; Hypertension ; Hypertrophy, Left Ventricular ; Logistic Models ; Male ; Obesity ; Risk Factors ; Smoke ; Smoking ; Uric Acid