Original Article
Office versus ambulatory blood pressure measurements in diagnosing diurnal hypertension in sub-Saharan Africans: a comparative cross-sectional study in Cameroon
Abstract
Background: Hypertension is the most frequent cardiovascular risk factor worldwide, with the greatest burden in low-income settings. We sought to know if the serial blood pressure (BP) readings measured in a single encounter, alongside other cardiovascular risk factors could reliably make the diagnosis of hypertension in a group of sub-Saharan Africans.
Methods: Between October and November 2016, we carried-out a cross-sectional descriptive and analytic study in Yaoundé, Cameroon. Adults of both sexes, aged ≥18 years were screened for cardiovascular risk factors using the WHO STEPwise approach. Participants with de novo elevated office BP underwent an ambulatory blood pressure measurement (ABPM) to ascertain hypertension. We then studied the determinants of ABPM diagnosed hypertension.
Results: Of the 26 participants who had an ABPM, 23 (88.5%) had hypertension, and 3 (11.5%) had white coat hypertension (WCH). Of those with hypertension (n=22), 6 (27.3%) were dippers, 2 (9.1%) were extreme dippers, 9 (40.9%) were non-dippers, and 5 (22.7%) were reverse dippers. The three participants with White coat effect were non-dippers. The determinants of de novo hypertension on ABPM were: Age >50 years (OR: 4.1, P=0.001), adiposity (OR: 6.2, P=0.002), pulse pressure >65 mmHg (OR: 21.4, P<0.001), and sex specific hyperuricemia (OR: 4.2, P=0.001). After adjusting for age, adiposity, pulse pressure, and hyperuricemia were still associated with de novo diurnal hypertension on ABPM.
Conclusions: In people with de novo raised office BP, 9-in-10 will have hypertension on ABPM especially when they are aged >50 years, have abdominal obesity, high pulse pressure, and hyperuricemia. Those with white coat effect appeared to have a blunted BP dipping pattern.
Methods: Between October and November 2016, we carried-out a cross-sectional descriptive and analytic study in Yaoundé, Cameroon. Adults of both sexes, aged ≥18 years were screened for cardiovascular risk factors using the WHO STEPwise approach. Participants with de novo elevated office BP underwent an ambulatory blood pressure measurement (ABPM) to ascertain hypertension. We then studied the determinants of ABPM diagnosed hypertension.
Results: Of the 26 participants who had an ABPM, 23 (88.5%) had hypertension, and 3 (11.5%) had white coat hypertension (WCH). Of those with hypertension (n=22), 6 (27.3%) were dippers, 2 (9.1%) were extreme dippers, 9 (40.9%) were non-dippers, and 5 (22.7%) were reverse dippers. The three participants with White coat effect were non-dippers. The determinants of de novo hypertension on ABPM were: Age >50 years (OR: 4.1, P=0.001), adiposity (OR: 6.2, P=0.002), pulse pressure >65 mmHg (OR: 21.4, P<0.001), and sex specific hyperuricemia (OR: 4.2, P=0.001). After adjusting for age, adiposity, pulse pressure, and hyperuricemia were still associated with de novo diurnal hypertension on ABPM.
Conclusions: In people with de novo raised office BP, 9-in-10 will have hypertension on ABPM especially when they are aged >50 years, have abdominal obesity, high pulse pressure, and hyperuricemia. Those with white coat effect appeared to have a blunted BP dipping pattern.
