Time to First Cigarette and the Risk of Hypertension: A Nationwide Representative Study in Korea

BACKGROUND: Although previous studies have explored the effect of smoking on blood pressure, little is still known about the role of time to first cigarette (TTFC)-an indicator of nicotine dependence-in hypertension. Therefore, we evaluated this association using representative nationwide data. METHODS: Current daily smokers (N = 941; aged 19-79 years) who participated in the 7th version of the Korea National Health and Nutrition Examination Survey I (2016) were included. We categorized participants into 4 groups according to their TTFC. Furthermore, we categorized participants into hypertensive and nonhypertensive groups based on whether they were taking antihypertensive medications or had high blood pressure (≥140/90 mm Hg). The association of daily TTFC and hypertension was examined without adjusting for any covariates; after adjusting for smoking behaviors; and after adjusting for demographic characteristics, socioeconomic status, health-related behaviors, and comorbidities. RESULTS: In the fully adjusted weighted regression analysis, participants reporting TTFC ≤ 5 minutes (vs. >60 minutes) had roughly twice the odds of having hypertension (95% confidence interval [CI] = 1.07-4.16) and the adjusted odds ratios compared with TTFC of >60 minutes were 1.53 (95% CI = 0.81-2.86) for 6-30 minutes and 1.31 (95% CI = 0.68-2.50) for 31-60 minutes (Ptrend = 0.03). CONCLUSIONS: Hypertension risk increases with shorter TTFC. Especially, TTFC of ≤5 minutes may prove valuable in assessing the risk of hypertension. Screening smokers based on their TTFC might be useful in assessing their risk of hypertension and smoking cessation programs.