Warfarin pharmacogenetics in a black Zimbabwean cohort: an observational prospective study.

Aim: A prospective observational study was conducted to evaluate the feasibility of implementing clinical guidelines for warfarin dosing in black Zimbabwean patients. Methods: CYP2C9*5, CYP2C9*6, CYP2C9*8 and CYP2C9*11 and VKORC1 c. 1639 G>A variations were observed in 62 study patients. Results & Conclusion: Overall, 39/62 (62.90%) participants did not receive a warfarin starting dose as would have been recommended by Clinical Pharmacogenetics Implementation Consortium guidelines. US FDA and Dutch Pharmacogenetics Working Group guidelines are based on CYP2C9*2 and CYP2C9*3 only, hence, unlikely useful in this cohort, where such variants were not detected. Clinical Pharmacogenetics Implementation Consortium guidelines, on the other hand, have a specific recommendation on the African-specific variants CYP2C9*5, CYP2C9*6 and CYP2C9*11, and are hence suitable for implementation in Zimbabwe and would help optimize warfarin doses in patients in the study cohort.

Investigation on the hereditary basis of colorectal cancers in an African population with frequent early onset cases.

BACKGROUND: Approximately 25% of colorectal cancer patients in sub-Saharan Africa are younger than 40 years, and hereditary factors may contribute. We investigated the frequency and patterns of inherited colorectal cancer among black Zimbabweans. METHODS: A population-based cross-sectional study of ninety individuals with a new diagnosis of colorectal cancer was carried out in Harare, Zimbabwe between November 2012 and December 2015. Phenotypic data was obtained using interviewer administered questionnaires, and reviewing clinical and pathology data. Cases were screened for mismatch repair deficiency by immunohistochemistry and/or microsatellite instability testing, and for MLH1, MSH2 and EPCAM deletions using multiplex ligation-dependent probe amplification. Next generation sequencing using a 16-gene panel was performed for cases with phenotypic features consistent with familial colorectal cancer. Variants were assessed for pathogenicity using the mean allele frequency, phenotypic features and searching online databases. RESULTS: Three Lynch syndrome cases were identified: MSH2 c.2634G>A pathogenic mutation, c.(1896+1_1897-1)_(*193_?)del , and one fulfilling the Amsterdam criteria, with MLH1 and PMS2 deficiency, but no identifiable pathogenic mutation. Two other cases had a strong family history of cancers, but the exact syndrome was not identified. The prevalence of Lynch syndrome was 3·3% (95% CI 0·7-9·4), and that of familial colorectal cancer was 5·6% (95% CI, 1·8-12·5). CONCLUSIONS: Identifying cases of inherited colorectal cancer in sub-Saharan Africa is feasible, and our findings can inform screening guidelines appropriate to this setting.

A case-control study of risk factors for colorectal cancer in an African population.

The interplay between hereditary and environmental factors in the causation of colorectal cancer in sub-Saharan Africa is poorly understood. We carried out a community based case-control study to identify the risk factors associated with colorectal cancer in Zimbabwe. We recruited 101 cases of colorectal cancer and 202 controls, matched for age, sex and domicile. Potential risk factors including family history, socioeconomic status, urbanization, diabetes mellitus and previous schistosomiasis were evaluated. Conditional logistic regression was used to estimate the odds ratios associated with the different factors. Cases were more likely to have a tertiary education (32.7 vs. 13.4%, P<0.001) and a higher income (18.8 vs. 6.9%, P=0.002). After multivariate analysis, diabetes mellitus [odds ratio (OR): 5.3; 95% confidence interval (CI): 1.4-19.9; P=0.012], previous urban domicile (OR: 2.8; 95% CI: 1.0-7.8; P=0.042), previous schistosomiasis (OR: 2.4; 95% CI: 1.4-4.2; P=0.001) and cancer in a first-degree relative (OR: 2.4; 95% CI: 1.2-4.8; P=0.018) were associated independently with colorectal cancer. Our findings suggest that family history, diabetes mellitus, previous schistosomiasis and approximation to a western lifestyle are the predominant associations with colorectal cancer in Africans. This offers opportunities for targeted prevention and hypothesis-driven research into the aetiology of colorectal cancer in this population.

Dietary patterns and colorectal cancer risk in Zimbabwe: A population based case-control study.

BACKGROUND: The rising incidence of colorectal cancer in sub-Saharan Africa may be partly caused by changing dietary patterns. We sought to establish the association between dietary patterns and colorectal cancer in Zimbabwe. METHODS: One hundred colorectal cancer cases and 200 community-based controls were recruited. Data were collected using a food frequency questionnaire, and dietary patterns derived by principal component analysis. Generalised linear and logistic regression models were used to assess the associations between dietary patterns, participant characteristics and colorectal cancer. RESULTS: Three main dietary patterns were identified: traditional African, urbanised and processed food. The traditional African diet appeared protective against colorectal cancer (Odds Ratio (OR) 0.35; 95% Confidence Interval (CI), 0.21 - 0.58), which had no association with the urban (OR 0.68; 95% CI, 0.43-1.08), or processed food (OR 0.91; 0.58-1.41) patterns. The traditional African diet was associated with rural domicile, (OR 1.26; 95% CI, 1.00-1.59), and a low income (OR1.48; 95% CI, 1.06-2.08). The urbanised diet was associated with urban domicile (OR 1.70; 95% CI, 1.38-2.10), secondary (OR 1.30; 95% CI, 1.07-1.59) or tertiary education (OR 1.48; 95% CI, 1.11-1.97), and monthly incomes of $201-500 (OR 1.30; 95% CI, 1.05-1.62), and the processed food pattern with tertiary education (OR 1.42; 95% CI, 1.05-1.92), and income >$1000/month (OR 1.48; 95% CI, 1.02-2.15). CONCLUSION: A shift away from protective, traditional African dietary patterns may partly explain the rising incidence of colorectal cancer in sub-Saharan Africa.

Medical Education Partnership Initiative (MEPI) in Zimbabwe: Outcomes and Challenges.

BACKGROUND: Sub-Saharan Africa has an inadequate number of health professionals, leading to a reduced capacity to respond to health challenges, including HIV/AIDS. From 2010 to 2015, the Medical Education Partnership Initiative (MEPI)-sponsored by the U.S. Presidents Emergency Plan for AIDS Relief (PEPFAR) and the National Institutes of Health (NIH)-was enthusiastically taken up by the University of Zimbabwe College of Health Sciences (UZCHS) and 12 other sub-Saharan African universities to develop models of training to improve medical education and research capacity. In this article, we describe the outcomes and challenges of MEPI in Zimbabwe. METHODS: UZCHS in partnership with the University of Colorado, Denver; Stanford University; University of Cape Town; University College London; and King's College London designed the Novel Education Clinical Trainees and Researchers (NECTAR) program and 2 linked awards addressing cardiovascular disease and mental health to pursue MEPI objectives. A range of medical education and research capacity-focused programs were implemented, including faculty development, research support, mentored scholars, visiting professors, community-based education, information and technology support, cross-cutting curricula, and collaboration with partner universities and the ministries of health and education. We analyzed quantitative and qualitative data from several data sources, including annual surveys of faculty, students, and other stakeholders; workshop exit surveys; and key informant interviews with NECTAR administrators and leaders and the UZCHS dean. FINDINGS: Improved Internet connectivity and electronic resource availability were early successes of NECTAR. Over the 5-year period, 69% (115 of 166) of faculty members attended at least 1 of 15 faculty development workshops. Forty-one faculty members underwent 1-year advanced faculty development training in medical education and leadership. Thirty-three mentored research scholars were trained under NECTAR, and 52 and 12 in cardiovascular and mental health programs, respectively. Twelve MEPI scholars had joined faculty by 2015. Full-time faculty grew by 36% (122 to 166), annual postgraduate and medical student enrollment increased by 61% (75 to 121) and 71% (123 to 210), respectively. To institutionalize and sustain MEPI innovations, the Research Support Center and the Department of Health Professions Education were established at UZCHS. CONCLUSION: MEPI has synergistically revitalized medical education, research capacity, and leadership at UZCHS. Investments in creating a new research center, health professions education department, and, programs have laid the foundation to help sustain faculty development and research capacity in the country.

The shifting epidemiology of colorectal cancer in sub-Saharan Africa.

The perception that colorectal cancer is rare in sub-Saharan Africa is widely held; however, it is unclear whether this is due to poor epidemiological data or to lower disease rates. The quality of epidemiological data has somewhat improved, and there is an ongoing transition to western dietary and lifestyle practices associated with colorectal cancer. The impact of these changes on the incidence of colorectal cancer is not as evident as it is with other non-communicable diseases such as diabetes. In this Viewpoint, we discuss the epidemiology of colorectal cancer in sub-Saharan Africa. Colorectal cancer in this region frequently occurs at an early age, often with distinctive histological characteristics. We detail the crucial need for hypothesis-driven research on the risk factors for colorectal cancer in this population and identify key research gaps. Should colorectal cancer occur more frequently than assumed, then commensurate allocation of resources will be needed for diagnosis and treatment.

Peripartum cardiomyopathy among cardiovascular patients referred for echocardiography at Parirenyatwa Teaching Hospital, Harare, Zimbabwe.

OBJECTIVES: The main aim was to evaluate the outcome of patients with peripartum cardiomyopathy (PPCM) within six months of diagnosis. The secondary aim was to describe demographic and clinical characteristics of patients with PPCM in Harare, Zimbabwe. METHODS: This was a prospective cohort study in which patients recruited into a detailed PPCM registry were followed up for six months. Echocardiograms were performed at enrolment, and three and six months after diagnosis, to determine left ventricular function. RESULTS: From 1 August 2012 to 31 July 2013, 43 patients with a new diagnosis of PPCM were recruited at Parirenyatwa Hospital in Harare. At six months, mean ejection fraction improved from 29.7 ± 9.8 to 44.9 ± 14.9%, p < 0.001 and New York Heart Association (NYHA) functional class improved significantly (p < 0.0001). Five (11.6%) patients died. CONCLUSIONS: Left ventricular function improved in a substantial number of patients (42.9%) in this Zimbabwean cohort compared to other African cohorts. However the mortality rate remained high.

The incidence and histo-pathological characteristics of colorectal cancer in a population based cancer registry in Zimbabwe.

BACKGROUND: Data on colorectal cancer (CRC) in sub-Saharan Africa is mainly based on hospital series which suggest low incidence and frequent early onset cancers. This study characterises colorectal cancer in a population-based cancer registry in Zimbabwe. METHODS: Cases of CRC recorded by the Zimbabwe National Cancer Registry between 2003 and 2012 were analysed. Demographic and pathological characteristics were compared according to ethnicity and age. Trends in age standardised incidence rates (ASR) were determined. RESULTS: There were 886 and 216 cases of CRC among black Africans and Caucasians respectively, and 26% of the black Africans were younger than 40 years. Signet ring cell carcinomas were more common among black Africans compared to Caucasians (4% vs 1%, p=0.027). ASR increased by 1.9%/year and 3.9%/year among black African males and females respectively. CONCLUSION: CRC incidence is rising among black Africans and has unique demographic and pathological characteristics.

Retrospective study of colorectal cancer in Zimbabwe: colonoscopic and clinical correlates.

AIM: To compare differences in the frequency of colorectal cancer at colonoscopy in Zimbabwe according to ethnicity. METHODS: All lower gastrointestinal endoscopic procedures performed between January 2006 and December 2011 at a gastroenterology clinic in Harare, Zimbabwe were reviewed. The demographic characteristics, clinical indications, differences in bowel preparation and the endoscopic and histological diagnoses were compared between different ethnic groups with emphasis on colorectal cancer. The clinical and demographic characteristics and the endoscopic findings were compared using the student t-test and the χ2 test, while the clinical indications associated with a diagnosis of colorectal cancer were determined by logistic regression. RESULTS: All colonoscopies and sigmoidoscopies performed in 1236 Caucasians, 460 black Africans and 109 Asians were analysed. Colorectal cancer was diagnosed more frequently in the black African patients compared to Caucasians or Asians (10% vs 3%, 10% vs 2%, P<0.001). However, polyps were less common among black Africans (5%) compared to both Caucasians (8%) and Asians (9%) (P=0.03). Among patients with colorectal cancer, black Africans tended to be younger than Caucasians, who were over-represented in the oldest age category; 32 % vs 2% were less than 50 years and 41% vs 78% were older than 60 years (P<0.001). Anaemia and weight loss were associated with colorectal cancer in both black African [odds ratio (OR): 2.73 (95%CI: 1.33-5.61) and 3.09 (1.35-7.07)] and Caucasian patients [OR: 6.65 (95%CI: 2.93-15.09) and 3.47 (1.52-7.94)]. CONCLUSION: The likelihood of diagnosing colorectal cancer in patients referred for colonoscopy in Zimbabwe is at least as likely among black Africans as it is among Caucasians.

Prednisolone and Mycobacterium indicus pranii in tuberculous pericarditis.

BACKGROUND: Tuberculous pericarditis is associated with high morbidity and mortality even if antituberculosis therapy is administered. We evaluated the effects of adjunctive glucocorticoid therapy and Mycobacterium indicus pranii immunotherapy in patients with tuberculous pericarditis. METHODS: Using a 2-by-2 factorial design, we randomly assigned 1400 adults with definite or probable tuberculous pericarditis to either prednisolone or placebo for 6 weeks and to either M. indicus pranii or placebo, administered in five injections over the course of 3 months. Two thirds of the participants had concomitant human immunodeficiency virus (HIV) infection. The primary efficacy outcome was a composite of death, cardiac tamponade requiring pericardiocentesis, or constrictive pericarditis. RESULTS: There was no significant difference in the primary outcome between patients who received prednisolone and those who received placebo (23.8% and 24.5%, respectively; hazard ratio, 0.95; 95% confidence interval [CI], 0.77 to 1.18; P=0.66) or between those who received M. indicus pranii immunotherapy and those who received placebo (25.0% and 24.3%, respectively; hazard ratio, 1.03; 95% CI, 0.82 to 1.29; P=0.81). Prednisolone therapy, as compared with placebo, was associated with significant reductions in the incidence of constrictive pericarditis (4.4% vs. 7.8%; hazard ratio, 0.56; 95% CI, 0.36 to 0.87; P=0.009) and hospitalization (20.7% vs. 25.2%; hazard ratio, 0.79; 95% CI, 0.63 to 0.99; P=0.04). Both prednisolone and M. indicus pranii, each as compared with placebo, were associated with a significant increase in the incidence of cancer (1.8% vs. 0.6%; hazard ratio, 3.27; 95% CI, 1.07 to 10.03; P=0.03, and 1.8% vs. 0.5%; hazard ratio, 3.69; 95% CI, 1.03 to 13.24; P=0.03, respectively), owing mainly to an increase in HIV-associated cancer. CONCLUSIONS: In patients with tuberculous pericarditis, neither prednisolone nor M. indicus pranii had a significant effect on the composite of death, cardiac tamponade requiring pericardiocentesis, or constrictive pericarditis. (Funded by the Canadian Institutes of Health Research and others; IMPI ClinicalTrials.gov number, NCT00810849.).

Rationale and design of the Investigation of the Management of Pericarditis (IMPI) trial: a 2 × 2 factorial randomized double-blind multicenter trial of adjunctive prednisolone and Mycobacterium w immunotherapy in tuberculous pericarditis.

BACKGROUND: In spite of antituberculosis chemotherapy, tuberculous (TB) pericarditis causes death or disability in nearly half of those affected. Attenuation of the inflammatory response in TB pericarditis may improve outcome by reducing cardiac tamponade and pericardial constriction, but there is uncertainty as to whether adjunctive immunomodulation with corticosteroids and Mycobacterium w (M. w) can safely reduce mortality and morbidity. OBJECTIVES: The primary objective of the IMPI Trial is to assess the effectiveness and safety of prednisolone and M. w immunotherapy in reducing the composite outcome of death, constriction, or cardiac tamponade requiring pericardial drainage in 1,400 patients with TB pericardial effusion. DESIGN: The IMPI trial is a multicenter international randomized double-blind placebo-controlled 2 × 2 factorial study. Eligible patients are randomly assigned to receive oral prednisolone or placebo for 6 weeks and M. w injection or placebo for 3 months. Patients are followed up at weeks 2, 4, and 6 and months 3 and 6 during the intervention period and 6-monthly thereafter for up to 4 years. The primary outcome is the first occurrence of death, pericardial constriction, or cardiac tamponade requiring pericardiocentesis. The secondary outcome is safety of immunomodulatory treatment measured by effect on opportunistic infections (eg, herpes zoster) and malignancy (eg, Kaposi sarcoma) and impact on measures of immunosuppression and the incidence of immune reconstitution disease. CONCLUSIONS: IMPI is the largest trial yet conducted comparing adjunctive immunotherapy in pericarditis. Its results will define the role of adjunctive corticosteroids and M. w immunotherapy in patients with TB pericardial effusion.

Cardiac disease in adolescents with delayed diagnosis of vertically acquired HIV infection.

BACKGROUND: At least one-third of human immunodeficiency virus (HIV)-infected infants survive to adolescence even without antiretroviral therapy (ART), but are at high risk of complications including cardiac disease. We investigated the characteristics of cardiac disease among adolescents with HIV infection diagnosed in late childhood who were receiving ambulatory HIV care in Harare, Zimbabwe. METHODS: Consecutive adolescents with vertically acquired HIV attending 2 HIV outpatient treatment clinics were studied. Assessment included clinical history and examination, and 2-dimensional, M-mode, pulsed- and continuous-wave Doppler echocardiography. RESULTS: Of 110 participants (47% male; median age, 15 years; interquartile range, 12-17 years), 78 (71%) were taking ART. Exertional dyspnea, chest pain, palpitations, and ankle swelling were reported by 47 (43%), 43 (39%), 10 (9%), and 7 (6%), respectively. The New York Heart Association score was ≥ 2 in 41 participants (37%). Echocardiography showed that 74 participants (67%) had left ventricular (LV; septal and/or free wall) hypertrophy and 27 (24%) had evidence of impaired LV relaxation or restrictive LV physiology. The estimated pulmonary artery systolic pressure (ePASP) was >30 mm Hg in 4 participants (3.6%); of these 2 also had right ventricular (RV) dilatation. Another 32 participants (29%), without elevated ePASP, had isolated RV dilatation. CONCLUSIONS: A significant burden of cardiac disease was seen among adolescents with vertically acquired HIV infection. More than half were asymptomatic yet had significant echocardiographic abnormalities. These findings highlight the need to screen this population in order to better define the geography, natural history, etiopathogenic mechanisms, and management (including the timing and choice of optimal therapeutic ART and cardiac drug interventions) to prevent development and/or progression of HIV-associated cardiac disease.