Clinical and Epidemiological Implications of 24‐Hour Ambulatory Blood Pressure Monitoring for the Diagnosis of Hypertension in Kenyan Adults: A Population‐Based Study

Abstract

BackgroundThe clinical and epidemiological implications of using ambulatory blood pressure monitoring (ABPM) for the diagnosis of hypertension have not been studied at a population level in sub‐Saharan Africa. We examined the impact of ABPM use among Kenyan adults.Methods and ResultsWe performed a nested case–control study of diagnostic accuracy. We selected an age‐stratified random sample of 1248 adults from the list of residents of the Kilifi Health and Demographic Surveillance System in Kenya. All participants underwent a screening blood pressure (BP) measurement. All those with screening BP ≥140/90 mm Hg and a random subset of those with screening BP <140/90 mm Hg were invited to undergo ABPM. Based on the 2 tests, participants were categorized as sustained hypertensive, masked hypertensive, “white coat” hypertensive, or normotensive. Analyses were weighted by the probability of undergoing ABPM. Screening BP ≥140/90 mm Hg was present in 359 of 986 participants, translating to a crude population prevalence of 23.1% (95% CI 16.5–31.5%). Age standardized prevalence of screening BP ≥140/90 mm Hg was 26.5% (95% CI 19.3–35.6%). On ABPM, 186 of 415 participants were confirmed to be hypertensive, with crude prevalence of 15.6% (95% CI 9.4–23.1%) and age‐standardized prevalence of 17.1% (95% CI 11.0–24.4%). Age‐standardized prevalence of masked and white coat hypertension were 7.6% (95% CI 2.8–13.7%) and 3.8% (95% CI 1.7–6.1%), respectively. The sensitivity and specificity of screening BP measurements were 80% (95% CI 73–86%) and 84% (95% CI 79–88%), respectively. BP indices and validity measures showed strong age‐related trends.ConclusionsScreening BP measurement significantly overestimated hypertension prevalence while failing to identify ≈50% of true hypertension diagnosed by ABPM. Our findings suggest significant clinical and epidemiological benefits of ABPM use for diagnosing hypertension in Kenyan adults.

Contribution of Ambulatory Blood Pressure Monitoring to the Management of Arterial Hypertension at Blaise Compaor&#233; University Hospital

“…The long delay could be explained by the cost of the exam and the fact that the medical costs are directly supported by the patients or their families. In a Kenyan study, 27% of the patients who were scheduled for a free ABPM on a population-based study in a rural area did not show up [8]. It was then concluded that the ABPM was not well-accepted in this context.…”

Diagnostic performance of clinic and home blood pressure measurements compared with ambulatory blood pressure: a systematic review and meta-analysis

“…Furthermore, some factors such as age, sex, measurement technique, and types of ABPM were highly associated with HT diagnosis (10)(11)(12). Then, a subgroup analysis by these factors may be useful to guide BP screening strategy.…”

Scaling up the use of home blood pressure monitoring in the management of hypertension in low‐income countries: A step towards curbing the burden of hypertension

“…Patients with a raised BP value on CBPM but a normal ABPM or HBPM value and who are not taking antihypertensive drugs are said to have WCH . In a recent community‐based case‐control study in Kenya including 1248 participants, CBPM significantly overestimated the prevalence of hypertension while missing about half of the participants with true hypertension diagnosed by ABPM . Even though WCH is associated with mild cardiovascular risk, studies have failed to demonstrate a benefit of antihypertensive treatment in preventing cardiovascular events in patients with WCH .…”

“…Finally, compared with CBPM, the BP values of ABPM and HBPM are reproducible and better correlate with cardiovascular risk, preclinical target organ damage, and cardiovascular events . Twenty‐four–hour ABPM has the unique role of identifying abnormal nocturnal BP patterns, which is an independent predictor of cardiovascular events …”