Sustained high blood pressure and 24-h ambulatory blood pressure monitoring in Tanzanian adolescents

Abstract

Estimates for prevalence of high blood pressure (BP) among adolescents in Africa vary widely and few studies, if any, have documented the results of the recommended stepwise BP screening. In this cross-sectional study in Tanzania, we aimed to estimate prevalence of sustained high BP in 3 public secondary schools using the American Academy of Pediatrics BP screening strategy. On Day 1, one screening automated office BP (AOBP) measurement (Step 1) was followed by two more AOBP measurements (Step 2). Repeat AOBP measurements were obtained after about one month on adolescents with high AOBP measurements on Day 1 (Step 3). Participants with sustained high BP underwent 24-h ambulatory BP monitoring (step 4). Of all 500 enrolled participants, the prevalence of high blood pressure at each step in the process was 36.6% (183), 25.6% (128), 10.2% (51), and 2.6%(13) respectively for Steps 1–4. All except 6 students completed all 4 steps of the BP screening algorithm as indicated. We conclude that diagnosis of hypertension in African adolescents should use multiple AOBP measurements over multiple days followed by 24-h ABPM. Screening for high BP in school settings appears to be feasible and could provide a platform for cardiovascular disease education and health promotion.

Hypertension among adolescents in sub-Saharan Africa: a systematic review

“…Of 79 studies shown in Table 2 , 39 studies (49.4%) used automated BP machines, 33 studies (41.7%) used manual (mercury or aneroid) BP machines, 2 studies (2.6%) used both automated and manual BP machines, and 4 studies (5.1%) used Finapres (Finger artery pressure)—an automated device which records BP measurements “continuously” from a finger artery. Only 3 studies used 24-h ambulatory BP monitoring for confirming HTN ( 4 , 71 , 72 ).…”

“…This raises concern about the accuracy of the HTN prevalence estimates and a potential possibility of an overestimated HTN burden ( 3 ). Adolescents are more likely than adults to experience white coat HTN ( 4 , 115 , 116 ). Moreover, majority of adolescents in SSA have never had their BP measured and are therefore more prone to the “white coat effect”, particularly when the BP measurements are taken on one occasion ( 4 ).…”

“…Adolescents are more likely than adults to experience white coat HTN ( 4 , 115 , 116 ). Moreover, majority of adolescents in SSA have never had their BP measured and are therefore more prone to the “white coat effect”, particularly when the BP measurements are taken on one occasion ( 4 ). This observation underscores the importance of following the standard BP measurement procedures particularly in this population to ensure accurate estimates.…”

“…Much less information is available from sub–Saharan Africa (SSA) where adolescents constitute about 18% of the population ( 2 ). In high-income countries, obesity is the major risk factor for HTN, and other traditional risk factors such as physical inactivity, unhealthy diet, and family history of HTN are also common ( 3 , 4 ). In SSA, potential risk factors related to poverty and tropical diseases, also referred to as “non-traditional” risk factors, may be common.…”

Head-to-head comparison of the WHO STEPwise approach with immediate unattended and delayed unattended automated blood pressure measurements during household-based screening: a diagnostic accuracy study in Lesotho

“…Several studies have shown that single-day blood pressure measurements have limited accuracy, misclassifying up to 30% diagnosed individuals. 7 , 8 , 9 Therefore, for reliable estimation of blood pressure, most guidelines recommend two or more measurements on separate days. 2 , 10 , 11 , 12 For population surveys, however, revisiting participants on a different day is highly resource-intensive or impossible, especially in remote rural areas or in mobile populations.…”