ASSOCIATIONS OF LONG-TERM VISIT-TO-VISIT BLOOD PRESSURE VARIABILITY WITH SUBCLINICAL KIDNEY DAMAGE AND ALBUMINURIA IN ADULTHOOD: A 30-YEAR PROSPECTIVE COHORT STUDY

Abstract

Objective: Recent evidence indicates that long-term visit-to-visit blood pressure variability (BPV) may be associated with the risk of cardiovascular disease. We therefore aimed to determine the potential associations of long-term BPV from childhood to middle age with subclinical kidney damage (SKD) and albuminuria in adulthood. Design and method: Using data from the ongoing cohort of Hanzhong Adolescent Hypertension study, which recruited children and adolescents aged 6 to 18 years at baseline, we assessed BP variability by standard deviation (SD) and average real variability (ARV) for 30 years (6 visits). Presence of SKD was defined as estimated glomerular filtration rate (eGFR) between 30 and 60 ml/min/ 1.73 m2 or elevated urinary albumin-to creatinine ratio (uACR) at least 30 mg/g. Albuminuria was defined as uACR greater than 30 mg/g. Results: During a follow-up of 30 years, of the 1771 participants, 204 SKD events occurred. After adjustment for demographic, clinical characteristics and mean BP during 30 years, higher SDSBP, ARVSBP, SDDBP, ARVDBP, SDMAP, ARVMAP and ARVPP were significantly associated with higher risk of SKD [ORs (95% CIs) were 1.14(1.06 - 1.23), 1.15(1.08 - 1.21), 1.12(1.06 - 1.17), 1.16(1.08 - 1.25), 1.12(1.07 - 1.17), 1.18(1.10 - 1.27) and 1.11(1.03 - 1.21), respectively]. When we used cumulative exposure to BP from childhood to adulthood instead of mean BP as adjustment factors, results were similar. In addition, greater long-term BPV was also associated with the risk of albuminuria [ORs (95% CIs) were 1.07(1.03 - 1.10) for SDSBP, 1.13(1.06 - 1.20) for ARVSBP, 1.11(1.06 - 1.17) for SDDBP, 1.14(1.06 - 1.23) for ARVDBP, 1.18(1.09 - 1.27) for ARVMAP and 1.08(1.01 - 1.17) for ARVPP]. Long-term BP variability for 30 years from childhood to middle age was associated with higher risk of SKD and albuminuria in adulthood, independent of mean BP or cumulative exposure to BP during follow-up. Conclusions: Identifying long-term BP variability from early age may assist in predicting kidney disease and cardiovascular disease in later life.