Jobert Richie Nansseu

Occupational exposure to blood, hepatitis B vaccine knowledge and uptake among medical students in Cameroon

BackgroundHepatitis B virus (HBV) is the most contagious blood borne pathogen. The risk of occupational exposure to HBV among health care workers is a major concern, especially medical trainees. In this study we describe the knowledge of risk factors for HBV infection, history of accidental exposure to blood, awareness of HBV vaccine and the vaccination status among medical students in Cameroon.MethodsIn April 2012, a cross-sectional survey was carried out using a pretested self-administered questionnaire among 111 medical students.ResultsSixty-two students (55.9%) had had at least one accidental exposure to blood since the beginning of their medical training, with a median of 2 (IQR, 1-3) exposures. There was a good knowledge of the risk factors for HBV infection and awareness of HBV vaccine among participants. However, only 20 (18%) participants had completed the three doses of primary HBV vaccination. Furthermore, only 2 of the 20 (10%) adequately vaccinated participants had a post-vaccination test to confirm a good immune response and thus an effective protection against HBV infection. The main reason for not being vaccinated was lack of money to pay for the vaccine (45.6%). Forty seven (42.3%) participants had been sensitized by their training institutions about the importance of HBV vaccination. These were more likely to be vaccinated compared to those who had not been sensitized (p<0,001).ConclusionThere is a high rate of accidental exposure to blood and a very low HBV vaccination uptake in medical students in Cameroon, leading to a high occupational risk of HBV infection. HBV vaccination should be strongly recommended for medical students and the vaccine made available free of charge at the beginning of their training.

Aspirin for primary prevention of cardiovascular disease

Although aspirin has a well-established role in preventing adverse events in patients with known cardiovascular disease (CVD), its benefit in patients without a history of CVD remains under scrutiny. Current data have provided insight into the risks of aspirin use, particularly bleeding, compared with its benefits in primary CVD prevention. Although aspirin is inexpensive and widely available, especially in developing countries, there is lack of evidence that the benefits outweigh the adverse events with continuous aspirin use in primary CVD prevention. Therefore, the decision to initiate aspirin therapy should be an individual clinical judgment that weighs the absolute benefit in reducing the risk of a first cardiovascular event against the absolute risk of major bleeding, and tailored to the patient’s CVD risk. This risk must be calculated, based on accurate and cost-benefit locally developed risk assessment tools, the most discriminating threshold be identified. Additionally, patients preferences should be taken into account when making the decision to initiate aspirin therapy in primary prevention of CVD or not. Physicians should continuously be trained to calculate their patients CVD risk, and concomitant strategies be emphasized.

Prevalence, infectivity and correlates of hepatitis B virus infection among pregnant women in a rural district of the Far North Region of Cameroon

BackgroundEpidemiological data on hepatitis B virus (HBV) infection among pregnant women in Cameroon are very scarce, especially in the rural milieu. The purpose of this study was to determine the prevalence and factors associated with HBV infection, and the infectivity of rural pregnant women in the Far North Region of Cameroon.MethodsA cross-sectional study was conducted in three rural health facilities of the Guidiguis health district between December 2013 and March 2014. We consecutively recruited 325 pregnant women attending antenatal consultations. A pretested questionnaire was used to collect socio-demographic data and factors associated with HBV infection. The presence of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and human immunodeficiency virus (HIV) were determined using commercial test strips. Regression analyses were used to assess correlates of HBV infection.ResultsThe mean age was 24.4 (SD5.6) years. Most women were married (97.2%) and housewives (96.4%), with less than secondary education level (80%). Only 4 women (1.2%) had been vaccinated against HBV. Thirty-three women (10.2%) were HBsAg-positive, of whom 4 (12.1%) were positive to HBeAg. The prevalence of HIV infection was 2.5% (8/325). Overall, 5 (1.5%) women were co-infected with HIV and HBV. Independent correlates of HBV infection included history of blood transfusion (adjusted odd ratio 12.59, 95% CI 1.46-108.89; p = 0.021) and concurrent infection by HIV (adjusted odd ratio 22.53, 95% CI 4.76-106.71; p < 0.0001).ConclusionThe prevalence of HBV infection among pregnant women in this rural milieu is high. History of blood transfusion and HIV infection are highly associated with HBV infection. The relative low rate of women positive to both HBsAg and HBeAg suggests that perinatal transmission of HBV might not be the prevailing mode of HBV transmission in this area.

Prevalence and incidence of pulmonary hypertension among HIV-infected people in Africa: a systematic review and meta-analysis

Objective Patients infected with HIV have a direly increased risk of developing pulmonary hypertension (PH), and of dying from the condition. While Africa carries the greatest burden of HIV infection worldwide, there is unclear data summarising the epidemiology of PH among HIV-infected people in this region. Our objective was to determine the prevalence and incidence of PH among HIV-infected people living across Africa. Design A systematic review and meta-analysis. Participants HIV-infected African people residing in Africa. Outcome Prevalence and incidence of PH diagnosed through echocardiography or right heart catheterisation. Data sources Articles published in PubMed/MEDLINE, EMBASE, African Journals Online and African Index Medicus between 1 January 1980 and 30 June 2016, without any language restriction. Results Overall, 121 studies were screened; 3 were included in this review: 1 from Southern Africa (South Africa), 1 from Eastern Africa (Tanzania) and 1 from Central Africa (Cameroon). These studies included HIV-infected adult patients selected based on presentation with cardiovascular symptoms. No study reported PH incidence or PH incidence/prevalence among children and adolescents. The quality assessment yielded moderate risk of bias. Ages of participants ranged between 18 and 78 years, and the proportion of females varied between 52.3% and 68.8%. The prevalence of PH in the pooled sample of 664 patients was 14% (95% CI 6%–23%). Limitations Only 3 studies were found eligible from 3 regions of the African continent. Conclusions The prevalence of PH among HIV-infected people in Africa seems very high. Further studies are urgently warranted to determine the incidence of HIV-induced PH, which must include all subregions of Africa. Trial registration number Review registration number PROSPERO CRD42016033863.

The highly neglected burden of resistant hypertension in Africa: a systematic review and meta-analysis

Objective The hypertension epidemic in Africa collectively with very low rates of blood pressure control may predict an incremented prevalence of resistant hypertension (RH) across the continent. The aim of this study was to determine the prevalence of RH and associated risk factors in Africa. Data sources We conducted a comprehensive search of electronic databases (PubMed, EMBASE, Africa Wide Information and Africa Index Medicus) completed by manual search of articles, regardless of language or publication date. Methods We included studies which have reported the prevalence and/or risk factors for RH in Africa from inception to 19 May 2016. Forest plots were drawn to visualise the combined prevalence of RH and extent of statistical heterogeneity between studies. Results Out of 259 retrieved studies, only 5 from Cameroon, Nigeria, Burkina Faso, Lesotho and Algeria with a total population of 4 068 patients were finally included in this review. There was no study from the Eastern part of Africa. Though the definition of RH was not similar across studies, its prevalence was respectively 11.7%, 4.9%, 14.6%, 14.3% and 19.0%, with an overall pooled prevalence of 12.1% (95% CI 8.0% to 17.7%). Potential risk factors were: non-compliance to treatment, ageing, male sex, dyslipidaemia, metabolic syndrome, previous cardiovascular events, physical inactivity and stress, but not excessive salt intake, alcohol and coffee ingestions. Moreover, diabetes, smoking, obesity and renal insufficiency yielded discrepant results. Conclusions There is a huge dearth of research on the epidemiology of RH in Africa. Thereby, an extensive study of RH prevalence and risk factors is still largely warranted to curtail the high and continuously increasing burden of hypertension across Africa.

Seroprevalence of hepatitis C virus infection in Cameroon: a systematic review and meta-analysis

Objective Better knowledge of hepatitis C virus (HCV) seroprevalence at the national level can help to implement pertinent strategies to address the HCV-related burden. The aim of this paper was to estimate the seroprevalence of HCV infection in Cameroon. Design Systematic review and meta-analysis. Participants People residing in Cameroon. Data sources Electronic databases including PubMed/MEDLINE, AJOL, WHO-Afro Library, Africa Index Medicus, National Institute of Statistics and National AIDS Control Committee, Cameroon from 1 January 2000 to 15 December 2016 were searched. English and French languages papers were considered. Two independent investigators selected studies. The methodological quality of the studies was assessed using the Newcastle–Ottawa scale. Results 31 studies including 36 407 individuals were finally considered. There was no national representative study. The overall pooled prevalence was 6.5% (95% CI 4.5% to 8.8%; I²=98.3%). A sensitivity analysis of individuals at low risk of HCV infection showed a pooled prevalence of 3.6% (95% CI 2.3% to 5.2%, I²=97.7%, 18 studies) among 22 860 individuals (general population, blood donors and pregnant women), which was higher than for a high-risk population (healthcare workers and people with other identified comorbidities), 12.2% (95% CI 4.9% to 22.2%; I²=98.3%, 13 studies); p=0.018. The prevalence was higher in the East region, in rural settings, and when using an enzyme immunoassay technique for detecting HCV antibodies. Sex, sites, study period, sample size, timing of data collection and methodological quality of studies were not sources of heterogeneity. Limitation One-third of studies (29.0%) had a low risk bias in their methodology and most were facility-based (87.1%). Conclusion The seroprevalence of HCV infection in Cameroon indicates the need for comprehensive and effective strategies to interrupt HCV transmission in the Cameroonian population. Specific attention is needed for the East region of the country, rural settings and high-risk populations. A national representative study is needed to provide better estimates.

Fructosamine measurement for diabetes mellitus diagnosis and monitoring: a systematic review and meta-analysis protocol

Introduction Fructosamine is a marker of glucose control reflecting the average glycaemic level over the preceding 2–3 weeks. Fructosamine has not gained as much popularity as glycated haemoglobin (HbA1c) for diabetes mellitus (DM) control monitoring, and the related underlying reasons remain unclear. We aim to search for and summarise available evidence on the accuracy of fructosamine measurements to diagnose and monitor DM. Methods and analysis This systematic review will include randomised control trials, controlled before-and-after studies, time series designs, cohort studies, case–control studies and cross-sectional surveys reporting the diagnosis and/or monitoring of DM (type 1 DM, type 2 DM and gestational DM) with fructosamine compared with other measures of glycaemia (fasting glucose, oral glucose tolerance test, random glucose, HbA1c), without any language restriction. We will perform electronic searches in PubMed, Scopus and other databases, supplemented with manual searches. Articles published from 1 January 1980 to 30 June 2015 will be eligible for inclusion in this review. Two authors will independently screen, select studies, extract data and assess the risk of bias with discrepancies resolved by consensus. We will assess clinical heterogeneity by examining the types of interventions and outcomes in each study, and pool studies judged to be clinically homogeneous. We will also assess statistical heterogeneity using the χ2 test of homogeneity and quantify it using the I2 statistic. Absolute accuracy measures (sensitivity, specificity) will be pooled in a bivariate random-effects model, allowing for intersetting variability. Negative and positive predictive values will be computed for fructosamine, compared with another measure of glycaemia from the pooled estimates of sensitivity and specificity, using Bayes’ theorem. Ethics and dissemination This systematic review will use data from published studies and does not require ethics approval. Findings will be published in a peer-reviewed journal and presented at scientific conferences. Trial registration number PROSPERO (ID=CRD42015015930).

Phenotypic and allelic distribution of the ABO and Rhesus (D) blood groups in the Cameroonian population

Data on blood group phenotypes are important for blood transfusion programs, for disease association and population genetics studies. This study aimed at reporting the phenotypic and allelic distribution of ABO and Rhesus (Rh) groups in various ethnolinguistic groups in the Cameroonians. We obtained ABO and Rhesus blood groups and self‐identified ethnicity from 14 546 Cameroonian students. Ethnicity was classified in seven major ethnolinguistic groups: Afro‐Asiatic, Nilo‐Saharan, Niger‐Kordofanian/West Atlantic, Niger‐Kordofanian/Adamawa‐Ubangui, Niger‐Kordofanian/Benue‐Congo/Bantu/Grassfield, Niger‐Kordofanian/Benue‐Congo/Bantu/Mbam and Niger‐Kordofanian/Benue‐Congo/Bantu/Equatorial. ABO allelic frequencies were determined using the Bernstein method. Differences in phenotypic distribution of blood groups were assessed using the chi‐square test; a P value <0.05 being considered as statistically significant. The frequencies of the antigens of blood groups O, A, B and AB were 48.62%, 25.07%, 21.86% and 4.45%, respectively. Rhesus‐positive was 96.32%. The allelic frequencies of O, A and B genes were 0.6978, 0.1605 and 0.1416, respectively. Phenotypic frequencies of the blood groups in the general study population and in the different ethnolinguistic groups were in agreement with Hardy–Weinberg equilibrium expectations (P > 0.05). The frequencies of O, A, and B blood phenotypes were significantly lower, respectively, in the Nilo‐Saharan group (P = 0.009), the Niger‐Kordofanian/Benue‐Congo/Bantu groups (P = 0.021) and the Niger‐Kordofanian/West‐Atlantic group. AB blood group was most frequent in the Niger‐Kordofanian/Adamawa‐Ubangui group (P = 0.024). Our study provides the first data on ethnic distribution of ABO and Rhesus blood groups in the Cameroonian population and suggests that its general profile is similar to those of several sub‐Saharan African populations. We found some significant differences in phenotypic distribution amongst major ethnolinguistic groups. These data may be important for blood donor recruitment policy and blood transfusion service in Cameroon.

Antiretroviral therapy related adverse effects: Can sub-Saharan Africa cope with the new “test and treat” policy of the World Health Organization?

BackgroundRecent studies have shown that early antiretroviral therapy (ART) initiation results in significant HIV transmission reduction. This is the rationale behind the “test and treat” policy of the World Health Organization (WHO). Implementation of this policy will lead to an increased incidence of ART-related adverse effects, especially in sub-Saharan Africa (SSA). Is the region yet ready to cope with such a challenging issue?Main bodyThe introduction and widespread use of ART have drastically changed the natural history of HIV/AIDS, but exposure to ART leads to serious medication-related adverse effects mainly explained by mitochondrial toxicities, and the situation will get worse in the near future. Indeed, ART is associated with an increased risk of developing cardiovascular disease, lipodystrophy, prediabetes and overt diabetes, insulin resistance and hyperlactatemia/lactic acidosis. The prevalence of these disorders is already high in SSA, and the situation will be exacerbated by the implementation of the new WHO recommendations. Most SSA countries are characterized by (extreme) poverty, very weak health systems, inadequate and low quality of health services, inaccessibility to existing health facilities, lack of (qualified) health personnel, lack of adequate equipment, inaccessibility and unaffordability of medicines, and heavy workload in a context of a double burden of disease. Additionally, there is dearth of data on the incidence and predictive factors of ART-related adverse effects in SSA, to anticipate on strategies that should be put in place to prevent the occurrence of these conditions or properly estimate the upcoming burden and prepare an adequate response plan. These are required if we are to anticipate and effectively prevent this upcoming burden.ConclusionWhile SSA would be the first region to experience the huge benefits of implementing the “test and treat” policy of the WHO, the region is not yet prepared to manage the consequential increased burden of ART-related toxic and metabolic complications. Urgent measures should be taken to fill the lacunae if SSA is not to become over-burdened by the consequences of the “test and treat” policy.

Assessment of the 10-year risk of cardiovascular events among a group of Sub-Saharan African post-menopausal women

BACKGROUND Post-menopausal women may be at particular risk of developing cardiovascu-lar disease due to metabolic changes occurring at menopause. The present study aimed to assess the 10-year cardiovascular risk (CVR) among a group of post-menopausal women and to deter-mine associated factors. METHODS This was a cross-sectional study conducted among post-menopausal women in Yaoundé, Cameroon. CVR was calculated using the Framingham risk score. RESULTS We enrolled 108 women, their ages ranging from 45 to 80 years, with a mean of 56.4 ± ± 6.9 years. CVR ranged between 1.2% and greater than 30% with a mean of 13.4 ± 8.7%. Forty-three (39.8%) participants had a low CVR (< 10%), 39 (36.1%) women had a moderate CVR (10-20%), and 21 (24.1%) women had a high CVR (> 20%). Low-density lipoproteins cholesterol (LDL-C; b = 3.27, p = 0.004), fasting plasma glucose (b = 5.40, p = 0.015), and diastolic blood pressure (DBP; b = 3.49, p < 0.0001) were independently associated with CVR. Women not married (i.e. single, divorced or widowed) (adjusted odds ratio [aOR] 4.66, p = 0.002), those with high titers of LDL-C (≥ 1.6 g/L; aOR 5.07, p = 0.001), and those with elevated DBP (≥ 90 mm Hg; aOR 8.10, p < 0.0001) presented an increased likelihood to be at an advanced level of CVR. CONCLUSIONS A significant number of post-menopausal women are at considerable risk of cardiovascular events in our setting. Therefore, they should be educated to adopt healthy life-styles for substantial reduction in their CVR.