Félicité Kamdem

Prevalence, awareness, treatment and control of hypertension in a self-selected sub-Saharan African urban population: a cross-sectional study

Objectives Hypertension has been established as a major public health problem in Africa, but its specific contributions to disease burden are still incompletely understood. We report the prevalence and determinants of hypertension, detection, treatment and control rates among adults in major cities in Cameroon. Design Cross-sectional study. Settings Community-based multicentre study in major cities in Cameroon. Participants Participants were self-selected urban dwellers from the Center, Littoral, North-West and West Regions, who attended on 17 May 2011 a screening campaign advertised through mass media. Primary and secondary outcomes measures Hypertension defined as systolic (and/or diastolic) blood pressure (BP)≥ 140 (90) mm Hg, or ongoing BP-lowering medications. Results In all, 2120 participants (1003 women) were included. Among them, 1007 (prevalence rate 47.5%) had hypertension, including 319 (awareness rate 31.7%) who were aware of their status. The prevalence of hypertension increased with age overall and by sex and region. Among aware hypertensive participants, 191 (treatment rate 59.9%) were on regular BP-lowering medication, and among those treated, 47 (controlled rate 24.6%) were at target BP levels (ie, systolic (and diastolic) BP<140 (90) mm Hg). In multivariable logistic regression analysis, male gender, advanced age, parental history of hypertension, diabetes mellitus, elevated waist and elevated body mass index (BMI) were the significant predictors of hypertension. Likewise, male gender, high BMI and physical inactivity were associated with poor control. Conclusions High prevalence of hypertension with low awareness, treatment and control were found in this urban population; these findings are significant and alarming with consideration to the various improvements in the access to healthcare and the continuing efforts to educate communities over the last few decades.

Prevalence and determinants of excessive daytime sleepiness in hypertensive patients: a cross-sectional study in Douala, Cameroon

Objective To determine the prevalence and determinants of excessive daytime sleepiness (EDS) among a group of sub-Saharan Africans living with hypertension. Design A cross-sectional study. Setting Cardiology outpatient unit of the Douala General Hospital in Cameroon. Participants Patients aged 15 years and over, being followed for hypertension between 1st January and 31st July 2013. Patients with unstable heart failure, stroke and head trauma were excluded. Main outcome measure EDS was the outcome of interest. It was defined as an Epworth sleeping scale greater or equal to 10. Logistic regression was used to identify factors associated with EDS. Results A total of 411 patients participated in this study, with a sex ratio (male/female) of 0.58 and a mean age of 55.56 years. No patient was underweight and the mean body mass index was 30 kg/m2. Controlled blood pressure was found in 92 (22.4%) patients. The prevalence of EDS was 62.78% (95% CI 58.08 to 67.47). The factors independently associated with EDS were: type 2 diabetes (OR 2.51; 95% CI 1 to 6.29), obesity (OR 2.75; 95% CI 1.52 to 4.97), snoring (OR 7.92; 95% CI 4.43 to 14.15) and uncontrolled blood pressure (OR 4.34; 95% CI 2.24 to 8.40). Conclusions A significant proportion of hypertensive patients suffer from EDS and present a high risk of sleep apnoea. Preventive measures targeted on weight loss, type 2 diabetes and snoring should be considered among these patients.

Prevalence and determinants of electrocardiographic abnormalities in sub-Saharan African individuals with type 2 diabetes.

Aim This study assessed the prevalence and determinants of electrocardiographic abnormalities in a group of type 2 diabetes patients recruited from two referral centres in Cameroon. Methods A total of 420 patients (49% men) receiving chronic diabetes care at the Douala General and Yaoundé Central hospitals were included. Electrocardiographic abnormalities were investigated, identified and related to potential determinants, with logistic regressions. Results The mean age and median duration of diagnosis were 56.7 years and four years, respectively. The main electrocardiographic aberrations (prevalence %) were: T-wave abnormalities (20.9%), Cornell product left ventricular hypertrophy (16.4%), arrhythmia (16.2%), ischaemic heart disease (13.6%), conduction defects (11.9%), QTc prolongation (10.2%) and ectopic beats (4.8%). Blood pressure variables were consistently associated with all electrocardiographic abnormalities. Diabetes-specific factors were associated with some abnormalities only. Conclusions Electrocardiographic aberrations in this population were dominated by repolarisation, conduction defects and left ventricular hypertrophy, and were more related to blood pressure than diabetes-specific factors.

Ambulatory blood pressure measurement in the main cities of Cameroon: prevalence of masked and white coat hypertension, and influence of body mass index

Introduction Identifying White Coat Hypertension (WCH) may avoid inappropriate commitment of individuals to lifelong and costly blood pressure (BP) lowering medications’. We assessed the prevalence and determinants of WCH in urban clinical settings in Cameroon. Methods Participants were a consecutive sample of adults, who underwent ambulatory BP measurements (ABPM) for the diagnosis of hypertension and evaluation of treatmentin three referral cardiac clinics in the cities of Yaounde and Douala, between January 2006 and July 2011. WCH was defined as an office-based systolic (or diastolic) BP ≥ 140(90) mmHg together with an average day time ambulatory systolic (and diastolic) BP < 135(85) mmHg. Results Of the 500 participants included, 188 (37.6%) were women, 230 (46%) were nonsmokers and 53 (10.6%) had diabetes mellitus. The mean age was 51.6±10.2years. The ABPM readings were higher in men than in women (p<0.05).The prevalence of WCH was 26.4% overall, 39.3% in women and22.4% in men (p=0.01).In multivariable analysis, body mass index was the only significant determinant of WCH (Odds ratio= 1.15(95% confidence intervals: 1.00-1.43), p<0.05). Conclusion The prevalence of WCH was high in our study population and was correlated only with BMI. Accurate measurement of BP and appropriate diagnosis of hypertension using ABPM in this setting may help limiting the consequences of over estimating hypertension severity on individuals, families and health systems.

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.

Clinical, echocardiographic, and therapeutic aspects of congenital heart diseases of children at Douala General Hospital: A cross-sectional study in sub-Saharan Africa

INTRODUCTION Cardiovascular diseases in pediatric pathologies have emerged in the recent years in sub-Saharan Africa (SSA), with congenital heart diseases (CHDs) being the most frequent. Unfortunately, their diagnosis is usually delayed, thereby increasing childhood morbidity and mortality. OBJECTIVES Describe the clinical, echocardiographic, and therapeutic aspects of CHDs of children at Douala General Hospital. METHODS We carried out a cross-sectional descriptive study over a 10-year period, from January 2006 to December 2015. Files and reports of cardiac ultrasounds of patients aged ≤ 15 years were reviewed. RESULTS We reviewed the medical records of 1616 children, of which 370 (22.9%) had CHD. The age range was 1 day to 15 years, with a mean of 26 months. Heart murmur was the most frequent clinical sign, seen in 72.3% of the cases. CHD with left-to-right shunt was seen in 61.8%, with ventricular septal defect being the most common (29.8% of all cases). The second most common CHDs were those due to obstruction (20.4%), mainly pulmonary stenosis (19.6% of all cases). Cyanogenic CHDs accounted for 17.8% of cases, dominated by tetralogy of Fallot (7.4% of all cases). Indications for surgical treatment was found in 171 (46.2%) patients, but due to financial constraints, only 48 (28.1%) patients were operated. Among those who underwent surgery, 66.7% were operated abroad, and Humanitarian organizations financed the surgical management of 58.3% of those operated. CONCLUSIONS CHDs are seen in one out of five children seen in the pediatric cardiology unit of our Hospital for suspected heart disease. Most cases are diagnosed late in life as toddlers. The rate of surgical correction remains low due to financial constraints, with most cases operated abroad with the assistance of Humanitarian organizations.

Gender disparities in pulmonary hypertension at a tertiary centre in Cameroon

BACKGROUND Pulmonary hypertension (PH) is a potent cause of heart failure and has been little investigated in the African setting. OBJECTIVE To investigate the effects of gender on the clinical presentation, echocardiographic features and outcomes of patients with PH in Douala, Cameroon. METHODS A prospective cohort study was conducted from March 2012 to December 2013 as part of the Pan African Pulmonary Hypertension Cohort study. PH was diagnosed by echocardiography and defined as a right ventricular systolic pressure >35 mmHg in the absence of acute right heart failure. Patients were followed up for a maximum of 12 months for primary endpoint mortality. RESULTS In total, 130 patients with PH were recruited; 71 (54.6%) were women. The median age was 59.2 years for men and 58.3 years for women (p=0.76). Active smoking and alcohol use were more frequent in men than women (both p<0.001), but women had greater exposure to indoor cooking fumes than men (p<0.001). Previous tuberculosis infection (11.3% v. 1.7%) and S3 gallop rhythm (30.9% v. 11.9%) were more common in women (both p<0.03). Women had a significantly higher mean systolic blood pressure (134 mmHg v. 125 mmHg; p=0.04) and pulse pressure (53.8 mmHg v. 44.9 mmHg; p=0.01) and a lower mean haemoglobin concentration (10.4 g/dL v. 12.4 g/dL; p<0.05) compared with men. Echocardiographic left ventricular (LV) systolic dysfunction was more frequent in men: mean LV ejection fraction 42.6% v. 51.5% (p=0.01) and mean fractional shortening 21.4% v. 28.6% (p=0.01). The overall mortality rate was 20.3%, and rates were similar in the two groups (Kaplan-Meier log rank 1.1; p=0.30). CONCLUSIONS Despite differences in baseline characteristics including cardiovascular risk factors, mortality rates on follow-up were similar in men and women in this study. However, these different baseline characteristics probably suggest differences in the pathogenesis of PH in men and women in our setting that need further investigation.

Prevalence and risk factors of chronic kidney disease in newly diagnosed and untreated hypertensive patients in cameroon: A cross-sectional study

Chronic kidney disease (CKD) has emerged as a worldwide problem and is a major cause for comorbidity in hypertensive patients. In an attempt to enhance awareness and to help in establishing preventive measures and care, it is necessary to describe CKD among newly diagnosed and untreated hypertensive patients. We conducted a cross-sectional study to describe the characteristics of CKD among newly diagnosed, treatment naïve, hypertensive patients in four health-care centers in the city of Douala, Cameroon. Sociodemographic and biological data were collected and serum creatinine was measured by enzymatic - colorimetric methods. We calculated estimated glomerular filtration rate (eGFR) by the Modification of Diet in Renal Disease equation and described CKD as eGFR <60 mL/min/1.73 m2. Logistic regression was further used to develop early clues of association. We included 839 newly diagnosed hypertensive treatment naïve patients, among which 412 (49.1%) men. The mean [±standard deviation (SD)] age was 51 (±11) years and was higher among those with CKD. Seventy-six had a family history of hypertension and 65 were known diabetic patients. Mean (±SD) eGFR was 94.4 (±33.3) mL/min and the prevalence of CKD was 12.4% (104/839). From multivariate logistic regression, age >55 years [OR: 5.29 (3.33-8.42)], obesity [OR: 0.15 (0.10-0.26)], kalemia [OR: 1.33 (1.03-1.72)] were independently associated to CKD. CKD is a common condition in newly diagnosed and untreated hypertensive patients in Cameroon. Individuals with hypertension should be carefully evaluated for the presence of CKD, especially those with decreased GFR.

Glucose homeostasis abnormalities among Cameroon patients with newly diagnosed hypertension

The authors assessed the frequency of glucose homeostasis abnormalities among 839 Cameroonians with newly diagnosed hypertension (mean age: 50.8±11 years; 49.9% female) in a cross‐sectional survey conducted at the Douala General Hospital, Douala, Cameroon. In all participants, blood pressure, fasting plasma glucose (FPG), and lipids were recorded. Impaired fasting glycemia was described as an FPG level between 100 and 125 mg/dL and provisional diabetes as an FPG level ≥126 mg/dL. The FPG was 101±30 mg/dL. The overall proportion of abnormal glucose homeostasis was 38.3%, while 7.7% of patients (n=65) had known diabetes. A total of 23.7% (n=199) had impaired fasting glycemia and 6.8% (n=57) had provisional diabetes. Multivariable logistic regression revealed that male sex (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.15–2.06), age older than 55 years (OR, 1.55; 95% CI, 1.15–2.09), and low‐density lipoprotein cholesterol >1 g/L (OR, 1.34; 95% CI, 1.00–1.82) were independently associated with abnormal glucose homeostasis (all P<.05). Glucose homeostasis abnormalities are highly prevalent among Cameroonian patients with newly diagnosed hypertension.

Prevalence and factors associated with hyperuricaemia in newly diagnosed and untreated hypertensives in a sub-Saharan African setting

BACKGROUND Few studies have evaluated the link between hyperuricaemia and cardiovascular disease in sub-Saharan Africa. AIMS To assess the prevalence of and factors associated with hyperuricaemia among newly diagnosed treatment-naïve hypertensive patients in sub-Saharan Africa. METHODS We performed a community-based cross-sectional study from January to December 2012 in Douala, Cameroon (Central Africa). We enrolled newly diagnosed treatment-naïve hypertensive patients, and excluded those with gout or a history of gout. Serum uric acid concentrations were measured by enzymatic colourimetric methods, and hyperuricaemia was defined as a serum uric acid concentration>70IU/mL. Fasting blood sugar concentrations, serum creatinine concentrations and lipid profiles were also measured. Logistic regression was used to study factors associated with hyperuricaemia. RESULTS We included 839 newly diagnosed treatment-naïve hypertensive patients (427 women and 412 men; mean age 51±11 years; mean serum uric acid concentration 60.5±16.5IU/L). The prevalence of hyperuricaemia was 31.8% (95% confidence interval [CI] 28.7-34.9) and did not differ by sex (132 women vs. 135 men; P=0.56). Multivariable logistic regression identified age>55 years (adjusted odds ratio [AOR] 1.65, 95% CI 1.12-2.29), family history of hypertension (AOR 1.65, 95% CI 1.01-2.67), waist circumference>102cm in men or>88cm in women (AOR 1.60, 95% CI 1.12-2.29), low-density lipoprotein cholesterol>1g/L (AOR 1.33, 95% CI 0.97-1.82) and triglycerides>1.5g/L (AOR 1.63, 95% CI 1.01-2.65) as independently associated with hyperuricaemia. CONCLUSION Hyperuricaemia is common among newly diagnosed treatment-naïve hypertensive patients in sub-Saharan Africa and is associated with some components of the metabolic syndrome.