Combined effect of hypertension and smoking on the death risk: data from a long-term 34-year prospective observation of Tomsk population

Abstract

Aim. To assess the risks of all-cause and cardiovascular mortality in smokers with hypertension (HTN) based on the results of a 34-year prospective observation of a Tomsk population.Material and methods. The study included 630 men and 916 women aged 2059 years who underwent primary screening in 1988-1991. HTN was established with blood pressure (BP) ³140/90 mm Hg and <140/90 mm Hg in persons taking antihypertensive drugs. People who smoked ³1 cigarette per day or stopped smoking less than a year ago were classified as smokers, and those who stopped smoking for more than one year were classified as non-smokers. Over 34-year observation, 535 deaths were identified, of which 232 were from cardiovascular causes.Results. The combination of hypertension and smoking increases the relative risk (RR) of all-cause death by 3,4 times in the general population, by 2,6 times among men and by 3,4 times among women. The risk of cardiovascular death also increases (RR 3,6). This effect was most pronounced among people in the younger age group (RR 8,5). Hypertensive smokers had a 1,5 times higher risk of premature all-cause death compared with nonsmokers with hypertension. Multivariate analysis found that smoking, regardless of other predictors, increases the all-cause and cardiovascular death risk by 2,61 and 2,77 times, respectively. HTN increases allcause and cardiovascular death risk by 1,32 and 1,52 times, respectively.Conclusion. Hypertension and smoking are among the most influential modifiable risk factors for premature death, and their combination increases the RR of allcause and cardiovascular death by 3,4 and 3,6 times, respectively. A more unfavorable prognosis has been established for women and young people. When HTN and smoking are combined, the 34-year survival prognosis decreases to 30,8% compared to 79,3% in individuals without these risk factors.

Keywords

• hypertension
• smoking
• mortality
• prospective study