Combined effects of child and adult elevated blood pressure on adult subclinical kidney damage and albuminuria: a 36-year prospective cohort study

Objective: Elevated blood pressure (BP) is associated with increased risk of chronic kidney disease. However, it is uncertain whether this risk is attenuated in individuals who acquire normal BP by adulthood. The present study examined the effect of child and adult BP levels on subclinical kidney damage (SKD) and albuminuria in adulthood. Design and method: Using data from the longitudinal cohort of Hanzhong Adolescent Hypertension Study, 1897 participants aged 6 to 18 years were enrolled and followed up for 36 years. Childhood elevated BP was defined according to the tables from the National Health Commission of the People's Republic of China. In adulthood, BP was classified as elevated if systolic BP greater than or equal to 140 mmHg, diastolic BP greater than or equal to 90 mmHg, or self-reported use of antihypertensive medications. Presence of SKD was defined as estimated glomerular filtration rate between 30 and 60 mL/min per 1.73 m2 or elevated urinary albumin-to creatinine ratio at least 30 mg/g. Albuminuria was defined as urinary albumin-to creatinine ratio greater than or equal to 30 mg/g. Results: Individuals with persistently elevated BP and individuals with normal childhood BP, but elevated adult BP had increased risk of SKD [odds ratios (ORs) 95% confidence interval (CI) were 2.46(1.68-3.60) and 3.28(1.85-5.82), respectively] in comparison with individuals with normal child and adult BP. In contrast, individuals with elevated BP as children but not as adults did not have significantly increased risk [OR 95% CI, 0.93(0.58-1.50)]. In addition, these individuals had a lower risk of increased SKD [OR 95% CI, 0.28(0.14-0.57)] in compared with those with persistently elevated BP. Consistent findings were observed in the risk of albuminuria. Conclusions: Individuals with persistently elevated BP from childhood to adulthood had increased risks of SKD and albuminuria. These risks were reduced if elevated BP during childhood resolved by adulthood.