Hypotension and survival: diagnostic criteria in Russian and United States population

Abstract

Aim. Based on Russian and United States population studies, to determine the criterion for distinguishing between normal and low blood pressure (BP), which is the most significant for predicting all-cause mortality.Material and methods. We used data from prospective Russian studies of 14730 men aged 19-82 years (9307 deaths per 342309 person-years of followup) and 6141 women aged 18-72 years (2101 deaths per 158727 person-years of follow-up), and two United States population studies: the First National Health and Nutrition Examination Survey (NHANES I) in conjunction with the NHANES I Epidemiologic Followup Study, and the Second National Health and Nutrition Examination Survey (NHANES II) in conjunction with the NHANES II Mortality Study. The total American cohort included only white subjects: 8618 men aged 25-75 years (3130 deaths per 121794 person-years of follow-up) and 11135 women 25-75 years (2465 deaths per 176676 person-years of follow-up). Primary examinations were carried out in 1971-1982, while the latest information on the subjects’ survival status was obtained in 2017 (Russia) and 1992 (USA). KaplanMeier curves and Cox proportional hazards models were created; all-cause death was taken into account as an outcome.Results. Survival analysis using Cox models, in which, in addition to BP levels, sex, age and risk factors were taken into account, showed that in persons with a pronounced BP decrease, survival is worse in comparison with those with normal BP. Mean dynamic BP, unfavorable for all-cause mortality, was below 70 and 68 mm Hg and 76 and 72 mm Hg in men and women in the Russian and US cohorts, respectively.Conclusion. Not only hypertension, but also severe hypotension is associated with increased all-cause mortality compared to normal BP. Survival decrease is manifested in severe hypotension, subject to sex and adjustment for age and risk factors.