Prevalence and Determinants of Masked Hypertension in Nigeria: The REMAH Study

Background Estimating the burden of hypertension in Nigeria hitherto relied on clinic blood pressure (BP) measurement alone. This excludes individuals with masked hypertension (MH) i.e. normotensive clinic but hypertensive out-of-clinic BP. Method In a nationally representative sample of adult Nigerians, we obtained clinic BP using auscultatory method and out-of-clinic BP by self-measured home BP with semi-automated oscillometric device. Clinic BP was average of 5 consecutive measurements and home BP was average of 3 days duplicate morning and evening readings. MH was clinic BP < 140 mmHg systolic and 90 mmHg diastolic and home BP ≥ 135 mmHg systolic and/or 85 mmHg diastolic. Result Among 933 participants, the prevalence of sustained, masked and white-coat hypertension was 28.3, 7.9 and 11.9 % respectively. Among subjects whose clinic BP were in the normotensive range (n=558), the prevalence of MH was 13%; 12% among untreated and 27% among treated individuals. The mutually adjusted odds ratios of having MH among all participants with normotensive clinic BP were 1.33 (95% confidence interval, 1.10–1.60) for a 10-year higher age, 1.59 (1.09–2.40) for a 10 mm Hg increment in systolic clinic BP, and 1.16 (1.08–1.28) for a 10mg/dl higher random blood glucose. The corresponding estimates in the untreated population were 1.24 (1.03–1.51), 1.56 (1.04–2.44) and 1.16 (1.08– 1.29), respectively. Conclusion MH is common in Nigeria and increasing age, clinic systolic BP and random blood glucose are the risk factors.

Ambulatory blood pressure is better associated with target organ damage than clinic blood pressure in patients with primary glomerular disease

Background Blood pressure is an important and modifiable cardiovascular risk factor. Ambulatory blood pressure monitoring (ABPM) provides valuable prognostic information in patients with chronic kidney disease (CKD), yet little is known about the association of various types of BP measurements with target organ damage (TOD) in patients with primary glomerular disease. The goal of this study was to investigate whether ambulatory blood pressure is better associated with TOD than clinic blood pressure in patients with primary glomerular disease. Methods 1178 patients with primary glomerular disease were recruited in this cross-sectional study. TOD were assessed by the following 4 parameters: left ventricular mass index (LVMI or LVH, left ventricular hypertrophy), estimated glomerular filtration rate (eGFR< 60 ml/min/1.73m2), albumin-to-creatinine ratio (ACR ≥ 30 mg/g) and carotid intima-media thickness (cIMT) or plaque. Receiver operating characteristic (ROC) curve and multivariate logistic regression analyses were used to evaluate the relationship between ambulatory or clinic systolic blood pressure (SBP) indexes and TOD. Results Among 1178 patients (mean age, 39 years,54% men), 116, 458, 1031 and 251 patients had LVH, eGFR < 60 ml/min/1.73m2, ACR ≥ 30 mg/g and cIMT≥0.9 mm or plaque respectively. Area under ROC curves for TOD in ambulatory SBP, especially nighttime SBP, was greater than that in clinic SBP (P < 0.05). Multivariate logistic regression analyses showed that 24 h SBP, daytime SBP and nighttime SBP were significantly associated with LVH, eGFR< 60 ml/min/1.73m2 and ACR ≥ 30 mg/g after adjustment for clinic SBP, while the association of clinic SBP was attenuated after further adjustment for nighttime SBP. Conclusions Ambulatory blood pressure, especially nighttime blood pressure, is probably superior to clinic blood pressure and has a significant association with TOD in primary glomerular disease patients.

Abstract P172: Orthostatic Hypotension And 24-hr Ambulatory Blood Pressure Monitoring In The Sprint Trial

Background: Clinic blood pressure (BP) is measured in the seated position, which can miss important home BP phenotypes such as low ambulatory BP (white coat effects) or high supine BP (nocturnal non-dippers). Orthostatic hypotension (OH) is determined based on BP measurements in both seated (or supine) and standing positions, and thus could theoretically identify these important phenotypes in clinic. Objective: To determine the association of OH with white coat effects or night-to-daytime systolic BP (SBP) Methods: SPRINT was a randomized trial testing the effects of intensive (<120 mmHg) or standard (<140 mmHg) SBP treatment strategies in adults at higher risk of cardiovascular disease. OH was assessed at 6, 12, or 24-mths and defined as a decrease in standing and mean seated SBP ≥20 or DBP ≥10 mmHg after 1 min of standing. White coat effects, based on 24-hr ambulatory BP monitoring performed at the 27-mth visit (every 30-minutes), were defined as the difference between 27-mth seated clinic and ambulatory BP ≥ 20/≥10 mmHg. SBP dipping ratio was defined as the ratio of night-to-daytime SBP >0.9. Results: Of 897 adults (mean age 71.5 [SD, 9.5] yrs, 28.7% female, 28.0% black), 128 had OH at least once. Among those with OH, 14.8% had white coat effects versus 7.2% among those without OH. Moreover, 68.8% of those with OH demonstrated non-dipping patterns versus only 52.0% of those without OH. OH was positively associated with both white coat effects (OR=2.24; 95% CI: 1.28, 4.27) and higher night-to-daytime SBP (β=0.04; 95% CI: 0.02, 0.06) ( Table ). Conclusions: Clinic-based assessments of OH may be a useful tool for identifying BP phenotypes often missed with traditional seated BP assessments.

Ambulatory blood pressure is better associated with target organ damage than clinic blood pressure in patients with primary glomerular disease

Background: Blood pressure is an important and modifiable cardiovascular risk factor. Ambulatory blood pressure monitoring (ABPM) provides valuable prognostic information in patients with chronic kidney disease (CKD), yet little is known about the association of various types of BP measurements with target organ damage (TOD) in patients with primary glomerular disease. The goal of this study was to investigate whether ambulatory blood pressure is better associated with TOD than clinic blood pressure in patients with primary glomerular disease. Methods: 1178 patients with primary glomerular disease were recruited in this cross-sectional study. TOD were assessed by the following 4 parameters: left ventricular mass index (LVMI or LVH, left ventricular hypertrophy), estimated glomerular filtration rate (eGFR<60ml/min/1.73m 2 ), albumin-to-creatinine ratio (ACR≥30mg/g) and carotid intima-media thickness (cIMT) or plaque. Receiver operating characteristic (ROC) curve and multivariate logistic regression analyses were used to evaluate the relationship between ambulatory or clinic systolic blood pressure (SBP) indexes and TOD. Results: Among 1178 patients (mean age, 39 years,54% men), 116, 458, 1031 and 251 patients had LVH, eGFR < 60 ml/min/1.73m 2 , ACR≥30mg/g and cIMT≥0.9mm or plaque respectively. Area under ROC curves for TOD in ambulatory SBP, especially nighttime SBP, was greater than that in clinic SBP ( P <0.05). Multivariate logistic regression analyses showed that 24h SBP, daytime SBP and nighttime SBP were significantly associated with LVH, eGFR<60 ml/min/1.73m 2 and ACR≥30mg/g after adjustment for clinic SBP, while the association of clinic SBP was attenuated after further adjustment for nighttime SBP. Conclusions: Ambulatory blood pressure, especially nighttime blood pressure, is probably superior to clinic blood pressure in predicting TOD in patients with primary glomerular disease.