Tracking of blood pressure from childhood to adulthood - A systematic review and meta-regression analysis

Background - A large number of studies have examined the tracking of blood pressure ( BP) from childhood to adulthood, but the reported findings are inconsistent and few systematic analyses have been conducted. Methods and Results - We conducted a systematic search of PubMed for studies that examined the tracking of BP from childhood to adulthood published between January 1970 and July 2006. From 301 retrieved papers, 50 cohort studies met our inclusion criteria and provided 617 data points ( Pearson/Spearman correlation coefficients) for systolic BP (SBP) and 547 data points for diastolic BP (DBP) for our meta-analysis. Information on sample characteristics and BP measurement protocols was extracted. Fisher z transformation and random-effects meta - regression analysis were conducted. The reported BP tracking correlation coefficients varied from -0.12 to 0.80 for SBP and from -0.16 to 0.70 for DBP, with an average of 0.38 for SBP and 0.28 for DBP. BP tracking varied significantly by baseline age and length of follow-up. The strength of BP tracking increased with baseline age by 0.012 for SBP ( P < 0.001) and 0.009 for DBP ( P < 0.001) and decreased with follow-up length by 0.008 for SBP ( P < 0.001) and 0.005 for DBP ( P < 0.001). BP tracking did not vary markedly across the number of BP measurements or race/population groups. Conclusions - Data from diverse populations show that the evidence for BP tracking from childhood into adulthood is strong. Childhood BP is associated with BP in later life, and early intervention is important.