Prevalence and determinants of blood pressure variability in pygmies of Southern region Cameroon.

INTRODUCTION: The impact of urbanization and living conditions on the prevalence of hypertension in the Cameroonian population is poorly known. AIM: To evaluate the prevalence and determinants of blood pressure (BP) in adult Pygmies and Bantus living in urban and rural areas of Southern Cameroon. PARTICIPANTS AND METHODS: This was a cross-sectional comparative study of 406 adults (96 urban Bantus, 100 urban Pygmies, 111 rural Bantus and 99 tropical rainforest Pygmies with a traditional Pygmies way of life), recruited in Southern Cameroon (mean age 42 ±â€Š17 years; 56.7% women). Sociodemographic, anthropometric and BP parameters were collected. Hypertension was defined as BP at least 140/90 mmHg and/or use of BP-lowering drug(s). RESULTS: The age-standardized prevalence of hypertension in urban Bantus, rural Bantus, urban Pygmies and traditional Pygmies was 18.0, 13.5, 9.3 and 4.1%, respectively. Mean SBP and DBP differed significantly according to Bantu vs. Pygmy ethnicity, and urban vs. rural residency. After multiple adjustments, mean arterial pressure was significantly associated with age, BMI, Bantu ancestry and urban residency. CONCLUSION: Bantu ethnicity and urban residency are significantly associated with high-BP among people from Southern Cameroon.

[How to formalise the supervision of learning of clinical reasoning]. / Formalisation de la supervision de l'apprentissage du raisonnement clinique.

Since clinical reasoning is central to most decisions made in the clinic, it is essential to teach it with the greatest relevance. Knowing that around 10% of learners encounter major difficulties in clinical reasoning during their course, training supervisors in effective pedagogical interventions is crucial. Here we summarize the methods allowing supervisors to identify errors of clinical reasoning in medical students and interns and we explain remediation techniques adapted to the types of error identified. Access to short illustrative videos of a MOOC (Massive Open On line Course) devoted to the supervision of clinical reasoning constitutes practical help for supervisors who are not expert in the complexity of medical pedagogy at bedside.

Cross-sectional survey evaluating blood pressure control ACHIEVEment in hypertensive patients treated with multiple anti-hypertensive agents in Belgium and Luxembourg.

OBJECTIVE: This study evaluates the actual blood pressure control rate and its estimation by general practitioners, the use of single-pill or free combinations, and the attitude towards single-pill combinations in primary care. METHODS: Cross-sectional observational survey in primary care between January 2015 and September 2016 in Belgium and Luxembourg. The participating general practitioners enrolled hypertensive patients taking at least 2 antihypertensive molecules (as fixed or free associations). RESULTS: 742 general practitioners included a total of 8,006 patients, with a mean age of 66 ± 12 years. Systolic blood pressure and diastolic blood pressure were respectively 141 ± 17 mmHg and 82 ± 10 mmHg (means ± SD). These patients had a blood pressure control rate of 45%, whereas it was estimated by general practitioners to be 60%. General practitioners with 11-25 years' experience performed better than general practitioners with 36-51 years' experience in the evaluation of blood pressure control. Combinations used were free in 39%, single-pill in 34% and mixed in 27% of the patients. Patients receiving single-pill combinations were younger than those treated with free combinations (63 ± 12 vs. 68 ± 12 years, p < 0.001), with fewer comorbidities (39 vs. 55%, p < 0.001). In patients treated solely with free pill associations, 66% of patient cases, general practitioners were willing to switch to a single-pill combination. The main reasons were improved adherence (76%) and better blood pressure control (64%). CONCLUSION: In patients requiring at least two antihypertensive drugs, blood pressure control rate remains low and is overestimated by general practitioners. Free combinations remain largely used although many general practitioners seem willing to shift to single-pill combinations. Treatment simplification could improve adherence and blood pressure control rate, which has been shown to lead to reduced morbidity and mortality.

Association of urinary sodium excretion with blood pressure and risk factors associated with hypertension among Cameroonian pygmies and bantus: a cross-sectional study.

BACKGROUND: High salt intake increases blood pressure (BP) and hypertension risk. This study aimed to examine association of urinary sodium excretion with BP and hypertension correlates among Cameroonian pygmies under hunter-gatherer subsistence mode and Bantus, living in urban area under unhealthy behavioral habits. METHODS: In this cross-sectional cluster sampling study, we randomly enrolled rural pygmies living in Lolodorf and urban Bantus living in Douala. The World Health Organization steps questionnaire was used to collect socio-demographic and lifestyle data. Height, weight, BP and single overnight spot urine samples were obtained in all participants. BP was measured in triplicate. Urinary sodium and potassium excretion was determined by flame photometry. Data were recorded and analyzed using SPSS 16.0. RESULTS: We included 150 Pygmies and 150 Bantus aged 38 ± 12 years and 33 ± 11 years, respectively (p <  0.0001). Compare to Bantus, pygmy's height and weight were respectively: 1.54 ± 0.09 m vs 1.72 ± 0.12 m; and 54.4 ± 9.2 kg vs 77.2 ± 14.8 kg, all p <  0.0001. Age-standardized prevalence of hypertension was 3.3% among Pygmies and 28% among Bantus (p <  0.0001). Age-adjusted systolic and diastolic BP were lower in Pygmies than in Bantus (107 ± 12 vs 119 ± 17 mmHg and 71 ± 11 vs 78 ± 13 mmHg respectively, all P <  0.0001). BP increased with age but to a lesser extent in Pygmies (all p <  0.01). Urinary sodium excretion was lower in Pygmies than in Bantus (46.9 ± 32.4 vs 121.5 ± 61.0 mmol/l, p <  0.0001). Systolic and diastolic BP were positively associated with urinary sodium excretion in Bantus (all p <  0.05). In the two groups, urinary potassium excretion was similar, and was not related to blood pressure. In the total study group and in Bantus taken separately, urinary sodium excretion was higher in hypertensive than in normotensive subjects. Multivariable logistic regression showed that urinary sodium excretion, Bantu status and age emerged as independent determinants of hypertension in the whole study group (OR (95%CI): 1.012 (1.005-1.018); 11.408 (3.599-36.165); 1.095 (1.057-1.135) respectively, p <  0.0001). CONCLUSION: Hunter-gatherer pygmies exhibit low level of urinary sodium excretion related to low rate of hypertension and slower BP increase with age. Salt intake was a major driver of hypertension in our study population. Our findings highlight the need of efforts to implement nationwide prevention programs promoting risk factor screening and healthier lifestyles including reduction of dietary salt intake in Cameroonian.

Arterial stiffness and cardiometabolic phenotype of Cameroonian Pygmies and Bantus.

BACKGROUND: Pygmies living in the Central African rainforest with a traditional hunter-gatherer lifestyle have a low incidence of cardiovascular diseases. Because of progressive loss of traditional habitat and ancestral lands, some Pygmies have migrated to urban areas and adopt specific Bantu lifestyles such as increased salt consumption and a sedentary way of life. We tested the hypothesis that migrant Pygmies could present with hemodynamic and metabolic characteristics different from those of traditional in-situ Pygmies and possibly closer to those of Bantu farmers. PATIENTS AND METHODS: The study included 148 Pygmies (94 traditional and 54 migrants) and 164 Bantus. Peripheral and central hemodynamics, aortic pulse wave velocity (PWV), and augmentation index corrected for heart rate (AIx) were measured, as well as fasting lipid profile. Urinary sodium and potassium excretion was also measured on a morning spot. RESULTS: Compared to Bantus, Pygmies had lower height (even between men and women, but men were taller than women in the three groups), weight, waist and hip circumference, peripheral and central blood pressure, total, low-density lipoprotein, and high-density lipoprotein cholesterol and apolipoprotein B100 levels, sodium urinary excretion, and lower prevalence of the metabolic syndrome. By contrast, they had a higher waist-to-hip ratio, and higher triglycerides levels, as compared to Bantu farmers. PWV and AIx did not differ between Bantus and Pygmies. Compared to traditional in-situ Pygmies, migrant Pygmies were not taller when adjusted for sex, had lower brachial and central blood pressure, higher PWV (adjusted for mean arterial pressure, BMI, and sex), and higher apolipoprotein B100 levels. In the whole population, multivariable analysis revealed that PWV was independently associated with age, weight, height, mean arterial pressure, total cholesterol, and hip circumference, whereas AIx was independently related to age, sex, height, heart rate, diastolic blood pressure, and group (from Bantu farmers to Pygmies). CONCLUSION: Comparisons between Bantus and Pygmies, and between migrant Pygmies and traditional in-situ Pygmies, showed mixed results, with favorable and deleterious hemodynamic and metabolic characteristics in all groups. This could be due to increased contacts between these populations, which blunt the expected differences and because the beneficial effects of the hunter-gatherer subsistence mode of traditional in-situ Pygmies are counterbalanced by unhealthy behavioral habits.

Prevalence, awareness, treatment, and control of hypertension among rural and urban dwellers of the Far North Region of Cameroon.

OBJECTIVE: To assess the prevalence and determinants of high blood pressure (BP) and awareness, treatment, and control rates in the Far North Region of Cameroon, where these variables have not been explored so far. METHODS: In total, 889 individuals (41.5% women) aged at least 18 years participated in a cross-sectional survey conducted in Maroua (urban area) and Tokombere (rural area) from November 2014 to May 2015, using a multistage cluster sampling frame. Anthropometric variables, BP, and fasting capillary glucose were assessed in all participants. Hypertension was defined as BP at least 140/90 mmHg or antihypertensive therapy and BP control as BP less than 140/90 mmHg. Prevalence estimates were age standardized to the Cameroon population. RESULTS: The prevalence of hypertension was 37.8% (rural: 34%; urban: 41.2%; men: 38.8%; women: 37.9%). Hypertension was associated with urban environment (odds ratio: 1.42; 95%; confidence interval 1.06-1.89), age at least 70 years (4.06; 2.02-6.14), male sex (4.06; 2.02-6.14), abdominal obesity (2.36; 1.54-3.61), and high blood sugar (2.01; 1.31-3.08). Among individuals with hypertension, 18.6% (rural: 17.9%; urban: 19.5%) were aware of having high BP. Among those aware, 29.3% (rural: 17.3%; urban: 36.3%) reported receiving treatment, of whom 16.3% (rural: 22.6%; urban: 4.2%) had BP controlled. Awareness, treatment, and BP control levels were higher in women than men. CONCLUSION: Hypertension is highly prevalent in Far North Cameroon and awareness, treatment, and control rates are low. Efforts to improve detection, treatment, and control of hypertension in Cameroon are needed.

Acute Kidney Injury in Elderly Patients With Chronic Kidney Disease: Do Angiotensin-Converting Enzyme Inhibitors Carry a Risk?

In contrast to angiotensin receptor blockers (ARBs), mainly excreted by the liver, the dosage of angiotensin-converting enzyme (ACE) inhibitors, cleared by the kidney, must be adapted to account for renal clearance in patients with chronic kidney disease (CKD) to avoid acute kidney injury (AKI). Community-acquired AKI and the use of ACE inhibitors or ARBs in the emergency department were retrospectively assessed in 324 patients with baseline stage 3 or higher CKD. After stepwise regression analysis, the use of ACE inhibitors (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.1; P=.02) and the presence of dehydration (OR, 30.8; 95% CI, 3.9-239.1) were associated with AKI. A total of 45% of patients using ACE inhibitors experienced overdosing, which causes most of the excess risk of AKI. These results suggest that dosage adjustment of ACE inhibitors to renal function or substitution of ACE inhibitors with ARBs could reduce the incidence of AKI. Moreover, ACE inhibitors and ARBs should be stopped in cases of dehydration.

Effects of antiretroviral therapy on arterial stiffness in Cameroonian HIV-infected patients.

BACKGROUND: HIV infection increases cardiovascular risk and highly active antiretroviral therapy may further augment it. We hypothesized that an increase in large artery stiffness may be a mechanism of enhanced cardiovascular risk in treated HIV-infected (HIV-T) patients. MATERIALS AND METHODS: Pulse wave velocity (PWV) and augmentation index (AI) were measured in 108 Cameroonian untreated HIV-infected (HIV-UT) patients and in 130 HIV-T patients. RESULTS: Brachial and aortic systolic blood pressure (BP), diastolic BP, and pulse pressure were higher in HIV-T patients than in HIV-UT patients (all, P < 0.01). PWV was comparable in HIV-T and HIV-UT patients (7.2 ± 1.5 vs. 7.46 ± 2.2 m/s, respectively, P = 0.3), whereas AI was higher in HIV-T patients than in HIV-UT patients (7.9 ± 5 vs. 5.76 ± 4%, respectively, P = 0.003). AI was associated independently with age, brachial systolic BP, brachial diastolic BP, and height in HIV patients (R = 0.75, P < 0.01). CONCLUSION: This study shows that pulse pressure and AI were increased in HIV-T patients, compared with matched HIV-UT patients, suggesting that highly active antiretroviral therapy could increase cardiovascular risk. However, PWV was not accelerated in HIV-T patients.

Infective endocarditis presenting as an isolated aneurysm of the posterior mitral leaflet.

We describe the case of a 64-year-old woman in whom an aneurysm located on the posterior mitral leaflet was detected. Blood cultures grew methicillin-sensitive Staphylococcus epidermidis, and histologic examination of the operative specimen showed polymorphonuclear neutrophilic infiltration of the valve wall associated with fibrin and necrosis, consistent with a diagnosis of endocarditis. The posterior mitral location of the aneurysm and the absence of vegetation are exceptionally rare in this setting. This case demonstrates that a mitral aneurysm may be the sole cardiac presentation of infective endocarditis.

Effects of hunter-gatherer subsistence mode on arterial distensibility in Cameroonian pygmies.

We aimed to assess whether arterial distensibility estimated by pulse wave velocity (PWV) and augmentation index (AI) differs between Cameroon traditional pygmies (TPs) on hunter-gather subsistence mode, contemporary pygmies who migrated to semiurban area, and the Bantou farmers (BFs) sharing the same environment. For that purpose, we recorded carotid-femoral PWV (ComplioR) in age and sex carefully matched 20 TPs, 20 contemporary pygmies, and 22 BFs. Aortic AI corrected for heart rate and blood pressures were generated from pressure wave analysis (SphygmoCor). Lipid profile was determined in TP and BF participants. TPs were shorter (P=0.02) with lower body weight (P<0.01) in comparison with contemporary pygmies and BFs. TPs had lower low-density lipoprotein cholesterol but higher high-density lipoprotein cholesterol than BFs (P<0.01). Their PWV (5.81±0.21 m/s) was slower (P=0.006) than that of contemporary pygmies (6.82±0.36 m/s) or BFs (6.93±0.29 m/s); however, after its adjustment for age, mean arterial pressure, and heart rate, the difference was slightly attenuated (P=0.051). PWV adjusted for weight did not differ between groups (P=0.10). In the whole study population but not in TPs taken separately, multivariate regression analysis revealed that PWV was independently associated with mean arterial pressure, age, and TP status (P<0.001), whereas age, mean arterial pressure, and height emerged as independent determinants of aortic AI corrected for heart rate (P<0.001). Aortic AI corrected for heart rate did not differ in the 3 groups. In conclusion, hunter-gather lifestyle is associated with low atherosclerosis risk translated by lower aortic stiffness attributed at least partly to low weight and blunted effects of aging and blood pressures on TP arterial structure and function.

Evaluation of standard and modified severity of illness scores in the obstetric patient.

PURPOSE: To test discrimination and calibration of APACHE-II and SAPS-II risk prediction scores in a cohort of obstetric patients, and to evaluate the effect of modifying these scores for the physiological changes in pregnancy. MATERIALS AND METHODS: A retrospective review of obstetric patients, 12 weeks gestation to 48 hours postpartum, admitted to the ICU for more than 24 hours. APACHE-II and SAPS-II, and versions modified for the physiological changes of pregnancy, were evaluated by receiver operating characteristic (ROC) curves and standardized mortality ratios (SMR). Multivariable analysis identified other parameters associated with mortality. RESULTS: Data were obtained from 332 patients from 5 countries, with a mortality rate of 12%. Mean (± SD) APACHE-II score was 16.8 ± 6.1 and SAPS-II score 26.5 ± 15.8. Good discrimination was demonstrated with area under the ROC curves of 0.82 and 0.78 respectively, with no improvement after modification for altered maternal physiology. APACHE-II overestimated mortality, with an SMR of 0.43 (0.52 after including diagnostic weighting) compared with 0.89 for SAPS-II. Bilirubin, albumin and Glasgow Coma Scale were independently associated with mortality. CONCLUSION: APACHE-II and SAPS-II are good discriminators of illness severity and may be valuable for comparing obstetric cohorts, but APACHE-II significantly over-estimates mortality.

High prevalence of nocturnal arterial hypertension and non-dipping in lung transplant recipients.

OBJECTIVE: An abnormal circadian blood pressure (BP) profile is associated with adverse cardiovascular and all-cause outcomes. It is highly prevalent after heart, liver and kidney transplantation. We aimed to assess the prevalence of an abnormal ambulatory BP pattern in lung transplant recipients (LTx). METHODS: Ambulatory BP monitoring (ABPM) was performed in 53 LTx and compared to those of 42 control subjects matched for age, gender and daytime BP. In 19 patients in whom at least two recordings were performed, we compared the first and the last one. RESULTS: The non-dipping pattern (a less than 10% reduction in nocturnal BP) was more prevalent in LTx than in control subjects (89 versus 64%, P < 0.01). Nighttime BP was higher in LTx than in control subjects (P < 0.01 and < 0.001 for systolic BP (SBP) and diastolic BP (DBP), respectively). The nocturnal reduction of BP was lower in LTx than in control subjects (3 versus 8% for SBP and 6 versus 13% for DBP, both P < 0.001). These results remained significant after adjustment for the presence of diabetes mellitus and creatinine clearance. In the 19 patients in whom ABPM was performed twice (mean interval between the two recordings was 22 months), ambulatory BP values remained unchanged between the two recordings, although the number of antihypertensive agents was significantly higher. CONCLUSION: An abnormal circadian BP profile is highly prevalent after lung transplantation. It is observed consistently over prolonged periods of time.

Albumin administration improves organ function in critically ill hypoalbuminemic patients: A prospective, randomized, controlled, pilot study.

OBJECTIVE: To test the hypothesis that administration of albumin to correct hypoalbuminemia might have beneficial effects on organ function in a mixed population of critically ill patients. DESIGN: : Prospective, controlled, randomized study. SETTING: Thirty-one-bed, mixed medicosurgical department of intensive care. PATIENTS: All adult patients with a serum albumin concentration < or =30 g/L were assessed for eligibility. Principal exclusion criteria were expected length of stay <72 hrs, life expectancy <3 months or a do-not-resuscitate order, albumin administration in the preceding 24 hrs, or evidence of fluid overload. INTERVENTIONS: The 100 patients were randomized to receive 300 mL of 20% albumin solution on the first day, then 200 mL/day provided their serum albumin concentration was <31 g/dL (albumin group), or to receive no albumin (control group). MEASUREMENTS AND MAIN RESULTS: The primary outcome was the effect of albumin administration on organ function as assessed by a delta Sequential Organ Failure Assessment score from day 1 to day 7 (or the day of intensive care discharge or death, whichever came first). The two groups of 50 patients were comparable at baseline for age, gender, albumin concentration, and Acute Physiology and Chronic Health Evaluation II score. Albumin concentration did not change over time in the control group but increased consistently in the albumin group (p < .001). Organ function improved more in the albumin than in the control group (p = .026), mainly due to a difference in respiratory, cardiovascular, and central nervous system components of the Sequential Organ Failure Assessment score. Diuretic use was identical in both groups, but mean fluid gain was almost three times higher in the control group (1679 +/- 1156 vs. 658 +/- 1101 mL, p = .04). Median daily calorie intake was higher in the albumin than in the control group (1122 [935-1158] vs. 760 [571-1077] kcal, p = .05). CONCLUSIONS: Albumin administration may improve organ function in hypoalbuminemic critically ill patients. It results in a less positive fluid balance and a better tolerance to enteral feeding.

Ethnic differences in arterial stiffness and wave reflections after cigarette smoking.

BACKGROUND: Smoking increases plasma nicotine. Nicotine releases catecholamines and alters arterial distensibility. The nicotine intake per cigarette is greater and serum cotinine levels, the proximate metabolite of nicotine, are higher in Blacks than in Whites. We tested the hypothesis that cigarette smoking increases the pulse wave velocity (PWV), a marker of arterial stiffness, and the augmentation index (AI), a measure of wave reflection, more in Blacks than in Whites. METHODS: We matched Black (n = 30) and White (n = 30) smokers for age, gender, body mass index and height. We determined carotid-femoral PWV (PWVCF) and carotid-radial PWV (PWVCR) (Complior), the AI derived from the aortic pressure waveform (applanation tonometry, Sphygmocor), blood pressure, heart rate (HR) and cotinine levels before and after cigarette smoking. We also performed measurements in 16 participants after sham smoking. RESULTS: Smoking increased the AI, PWVCF and PWVCR in the whole population (all P < 0.05, n = 60). Increases in the AI and PWV were positively related to serum cotinine levels (all P < 0.05). Smoking increased serum cotinine (P = 0.01) and mean blood pressure (P = 0.03) more, but raised the HR to a lesser extent, in Blacks [+8 +/- 4 versus +13 +/- 6 beats/min in Whites (mean +/- SD), P = 0.01]. Blacks disclosed larger increases in AI adjusted for HR (Blacks, +7.2 +/- 8 versus Whites, +4.4 +/- 8%; P = 0.03), PWVCF (Blacks, +1.1 +/- 0.2 versus Whites, +0.6 +/- 0.3 m/s; P < 0.01) and PWVCR (Blacks, +1.4 +/- 0.1 versus Whites, +0.7 +/- 0.4 m/s; P < 0.01) normalized for the mean blood pressure. No changes were observed with sham smoking. CONCLUSIONS: Smoking acutely increases the PWV and AI in Blacks more than in Whites. Differences in nicotine metabolism and beta-adrenergic sensitivity could explain these findings.

Role of endothelins and nitric oxide in the pulmonary circulation of perinatal lambs during hyperoxia and hypoxia.

Endothelins (ET) have opposite vascular effects mediated through different receptors: ET(A) receptors mediating vasoconstriction and ET(B) receptors mediating vasoconstriction as well as vasodilation. The role of ET in acute hypoxic pulmonary vasoconstriction (HPV) was studied after dual ET receptor blockade with bosentan and nitric oxide (NO) synthase inhibition with nitro-L-arginine (L-NA). We started from the hypothesis that ET antagonism may inhibit HPV but, if not, would do so after NO synthase inhibition. HPV was evaluated in anesthetized lambs, with an intact pulmonary circulation, by the increase in the mean pulmonary artery pressure (Ppa) minus occluded Ppa (Ppao) gradient in response to hypoxia (inspiratory oxygen fraction of 0.1) at different levels of pulmonary flow (multipoint pressure/flow relationships). ET receptor antagonism decreased pulmonary and systemic vascular tone both in hyperoxia and hypoxia. ET antagonism had no effect on HPV. NO synthase inhibition increased pulmonary vascular tone more in hypoxia than in hyperoxia so that HPV was enhanced. After L-NA, bosentan still decreased pulmonary vascular tone in hypoxia but did not affect the magnitude of HPV. The present results suggest that ET and NO are involved in the regulation of basal pulmonary vascular tone. Furthermore, the vasodilator effect of bosentan persisted in the presence of NO synthase inhibition, suggesting a non NO-dependent vasodilator mechanism. The results from these experiments are in agreement with the idea that ET do not play a major role in HPV in the perinatal lamb, even when it is enhanced by NO synthase inhibition.

Endothelin antagonists: new bullets against lung injury?

Acute lung injury is a syndrome of inflammation and of increased permeability of the blood-gas barrier. Endothelins are thought to exert proinflammatory effects. Kuklin and colleagues show that the endothelin receptor antagonist tezosentan reduces pulmonary edema in endotoxemic sheep, in parallel with a prevention of protein kinase C-alpha activation. In turn, the level of some cytokines increased after tezosentan treatment. Whether these contrasting effects of endothelin blockade on inflammatory mechanisms have clinical relevance and whether these agents might benefit patients with acute lung injury is unknown.