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

Introduction: Hypertension (HTN) among adolescents is common in high-income countries, and leads to increased premature cardiovascular diseases (CVD). In sub-Saharan Africa (SSA), the prevalence of HTN among adolescents, associated risk factors and CVD complications are not well-described. Such data is needed for planning public health programs to prevent premature CVD in SSA. Methods: We systematically searched 5 databases (MEDLINE, Embase, Google Scholar, Web of Science, and African Index Medicus) from their establishment to December 2021. Key search terms were: adolescent, arterial hypertension, and names of the 48 countries in SSA. We used Covidence® to manage the search results. The review was registered in the Open Science Framework (OSF) https://osf.io/p5sbt/. Results: We identified 4,008 articles out of which we screened 3,088 abstracts, and reviewed 583 full-text articles. We finally included 92 articles that were published between 1968 to December 2021. The majority were cross-sectional studies (80%) and conducted in school settings (78%). The risk of bias was low for 59 studies (64.1%), moderate for 29 studies (31.5%), and high for 4 studies (4.3%). Overall, the prevalence of HTN varied widely from 0.18% to 34.0% with a median (IQR) of 5.5% (3.1%, 11.1%). It was relatively higher in studies using automated blood pressure (BP) devices, and in studies defining HTN using thresholds based on percentile BP distribution for one's height, age, and sex. In addition, the prevalence of HTN was significantly higher in studies from Southern Africa region of SSA and positively correlated with the year of publication. Across studies, traditional risk factors such as age, sex, body mass index, and physical inactivity, were commonly found to be associated with HTN. In contrast, non-traditional risk factors related to poverty and tropical diseases were rarely assessed. Only three studies investigated the CVD complications related to HTN in the study population. Conclusion: The prevalence of HTN among adolescents in SSA is high indicating that this is a major health problem. Data on non-traditional risk factors and complications are scarce. Longitudinal studies are needed to clearly define the rates, causes, and complications of HTN. Systematic Review Registration: https://osf.io/p5sbt/, identifier (10.17605/OSF.IO/P5SBT).

Routine health check-ups for adolescents in Mwanza City, Tanzania: stakeholders' recommendations on its content, venue, and mode of delivery.

BACKGROUND: Routine adolescent health screening aiming at the detection of unnoticed medical problems may increase awareness among policy makers and contribute to improved health in this population. Research is needed to inform the World Health Organization (WHO) and national health programs to provide evidence-based guidance on whether public health systems should offer comprehensive adolescent health screening, what should be included in different contexts, and how it should be delivered. We conducted formative research to define the content and delivery strategies for health check-ups to be performed in young (10-14 years) and older (15-19 years) adolescents, and to assess whether such services are likely to be acceptable and feasible in Tanzania. METHODS: As part of a collaborative research program coordinated by WHO in Chitungwiza, Zimbabwe; Mwanza City, Tanzania; and Cape Coast, Ghana a series of key informant interviews were conducted from April to July 2020, using a semi-structured guide with purposively selected stakeholders from government departments, non-governmental and community-based organisations, schools and health facilities. Data transcripts were coded using NVivo 12 software and thematic analysis was performed. RESULTS: We report results from 31 key informant interviews to address four main domains: proposed health conditions for routine health check-ups, health interventions to be combined with such check-ups, preferable venues, and the mode for delivering such screening activities. Stakeholders were supportive of introducing routine health check-ups among adolescents. They recommended focusing on non-communicable diseases, physical disabilities, common mental health problems, reproductive health problems, specific communicable diseases, and hygiene-related problems. They also recommended combining counselling and family planning information with these check-ups. Three venues were proposed: schools, community settings (to reach out-of-school adolescents), and youth-friendly health facilities (for conditions requiring a high level of confidentiality). CONCLUSIONS: Stakeholders were supportive of the proposed routine health check-ups for adolescents, recommending specific health conditions to be screened for in both community and school settings. Based on the above, we plan to conduct implementation research to determine the number of new treatable conditions detected, and the costs of offering such services. In the longer term, evaluation of their health impact and cost-effectiveness will be required to guide policy.

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

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.

Prevalence of high blood pressure and associated factors among adolescents and young people in Tanzania and Uganda.

We conducted a cross-sectional study among school/college students in Tanzania and Uganda to determine the prevalence of high blood pressure (BP) and associated factors. Participants were classified to have high BP if they had pre-hypertension or hypertension. Interviews were done using the WHO STEPS instrument. Using data from both countries (n = 1596), the overall prevalence of high BP was 40% (95% CI: 37-42). The prevalence of pre-hypertension was 29% (95% CI: 26-31) and that of hypertension was 11% (95% CI: 10-13). High BP was independently associated with obesity (aOR = 6.7, 95% CI: 2.2-20.0), male sex (aOR = 3.2, 95% CI: 2.4-4.4), and among males aged above 20 years (aOR = 5.5, 95% CI: 2.9-10.5). Consumption of fruits/vegetables was associated with decreased odds for high BP (aOR = 0.7, 95% CI: 0.50-0.98). The increasing burden of pre-hypertension across age groups could explain the early onset of hypertension and cardiovascular diseases (CVDs) among young African adults. There is a need for longitudinal studies to explore the drivers of pre-hypertension in East African adolescents.