Masked uncontrolled hypertension among elderly black sub-saharan africans compared to younger adults: a cross-sectional in-hospital study.

BACKGROUND: Although aging and being of African descent are well-known risk factors for masked uncontrolled hypertension (MUCH), data on MUCH among elderly black sub-Saharan Africans (BSSA) are limited. Furthermore, it is unclear whether the determinants of MUCH in younger individuals differ from those in the elderly. OBJECTIVE: This study aimed to determine the prevalence and risk factors associated with MUCH in both elderly and younger BSSA individuals. METHODS: In this study, 168 patients with treated hypertension were assessed for medical history, clinical examination, fundoscopy, echocardiography, and laboratory data. All patients underwent ambulatory blood pressure (BP) monitoring for 24 h. MUCH was diagnosed if the average 24-h mean BP ≥ 130/80 mmHg, the daytime mean BP ≥ 135/85 mmHg, and/or the nighttime mean BP ≥ 120/70 mmHg, despite controlled clinic BP (≤ 140/90 mmHg). Logistic regression analysis was performed to assess independent factors associated with MUCH, including elderly and younger adults separately. P-values < 0.05 were used to indicate statistical significance. RESULTS: Of the 168 patients aged 53.6 ± 11.6 years, 92 (54.8%) were men, with a sex ratio of 1.2, and, 66 (39%) were aged ≥ 60 years. The proportion of patients with MUCH (27.4% for all patients) was significantly higher (p = 0.002) among elderly patients than among younger patients (45.5% vs. 15.7%). Diabetes mellitus (adjusted odds ratio [aOR], 2.44; 95% confidence interval [CI], 1.27-4.46; p = 0.043), anemia (aOR, 3.18; 95% CI, 1.07-5.81; p = 0.043), hypertensive retinopathy (aOR, 4.50; 95% CI, 1.57-5.4; p = 0.043), and left ventricular hypertrophy (aOR, 4.48; 95% CI, 2.26-8.35; p = 0.043) were independently associated with MUCH in the elderly. In younger individuals, male gender (aOR, 2.16; 95% CI, (1.33-4.80); p = 0.029), obesity (aOR, 3.02; 95% CI, (1.26-5.32); p = 0.001), and left ventricular hypertrophy (LVH) (aOR, 3.08; 95% CI, (2.14-6.24); p = 0.019) were independently associated with MUCH were independently associated with MUCH. CONCLUSION: MUCH is more prevalent among elderly than among younger BSSA individuals. Determinants of MUCH vary by age. MUCH prevention and management strategies should be age-specific.

Insulin resistance-related differences in the relationship between left ventricular hypertrophy and cardiorespiratory fitness in hypertensive Black sub-Saharan Africans.

BACKGROUND: Left ventricular hypertrophy (LVH) is associated with impaired cardiorespiratory fitness (CRF), a surrogate marker of poor outcome. Insulin resistance (IR) plays a central role in all stages of cardiovascular disease continuum. This study evaluates IR-related differences in the relationship between left ventricular mass (LVM) and CRF in asymptomatic newly diagnosed hypertensive Black sub-Saharan Africans. METHODS: In this cross-sectional observational study, 126 asymptomatic newly diagnosed hypertensive participants (50.5 ± 9.5 years) underwent comprehensive resting transthoracic echocardiographic examination and maximal incremental cardiopulmonary exercise test (CPET). CRF was estimated in maximal oxygen uptake (VO2max). CPET results were compared between participants with and without LVH. Multivariate analysis examined the influence of IR on the observed differences. RESULTS: Those with LVH had lower VO2max (15.7 ± 5.5 mL min-1 kg-1 vs. 18.4 ± 3.7 mL min-1 kg-1; P = 0.001) than those without LVH. In patients with IR, LVM (r = -0.261, P = 0.012), LVM indexed to body surface area (LVMIbsa; r = -0.229, P = 0.027), and LVM indexed to height to an allometric power of 2.7 (LVMIh2.7; r = -0.351, P = 0.001), and VO2max were negatively correlated. In hypertensive patients without IR, these same parameters and VO2max have no significant correlation. Body mass index (BMI), LVM, and LVMIbsa emerged as independent determinants of VO2max, explaining 46.9% of its variability (overall P = 0.001) in IR participants, a relationship not found in participants without IR. CONCLUSIONS: IR may participate in the deterioration of CRF associated with LVH. Measures to improve insulin sensitivity should be considered for improving CRF and therefore the prognosis of insulin-resistant hypertensive patients. Targeting IR in hypertensive patients with LVH could improve prognosis.

Association between insulin resistance and left ventricular hypertrophy in asymptomatic, Black, sub-Saharan African, hypertensive patients: a case-control study.

BACKGROUND: Conflicting information exists regarding the association between insulin resistance (IR) and left ventricular hypertrophy (LVH). We described the associations between obesity, fasting insulinemia, homeostasis model assessment of insulin resistance (HOMA-IR), and LVH in Black patients with essential hypertension. METHODS: A case-control study was conducted at the Centre Médical de Kinshasa (CMK), the Democratic Republic of the Congo, between January and December 2019. Cases and controls were hypertensive patients with and without LVH, respectively. The relationships between obesity indices, physical inactivity, glucose metabolism and lipid disorder parameters, and LVH were assessed using linear and logistic regression analyses in simple and univariate exploratory analyses, respectively. When differences were observed between LVH and independent variables, the effects of potential confounders were studied through the use of multiple linear regression and in conditional logistic regression in multivariate analyses. The coefficients of determination (R2), adjusted odds ratios (aORs), and their 95% confidence intervals (95% CIs) were calculated to determine associations between LVH and the independent variables. RESULTS: Eighty-eight LVH cases (52 men) were compared against 132 controls (81 men). Variation in left ventricular mass (LVM) could be predicted by the following variables: age (19%), duration of hypertension (31.3%), body mass index (BMI, 44.4%), waist circumference (WC, 42.5%), glycemia (20%), insulinemia (44.8%), and HOMA-IR (43.7%). Hypertension duration, BMI, insulinemia, and HOMA-IR explained 68.3% of LVM variability in the multiple linear regression analysis. In the logistic regression model, obesity increased the risk of LVH by threefold [aOR 2.8; 95% CI (1.06-7.4); p = 0.038], and IR increased the risk of LVH by eightfold [aOR 8.4; 95 (3.7-15.7); p < 0.001]. CONCLUSION: Obesity and IR appear to be the primary predictors of LVH in Black sub-Saharan African hypertensive patients. The comprehensive management of cardiovascular risk factors should be emphasized, with particular attention paid to obesity and IR. A prospective population-based study of Black sub-Saharan individuals that includes the use of serial imaging remains essential to better understand subclinical LV deterioration over time and to confirm the role played by IR in Black sub-Saharan individuals with hypertension.