Overall and central obesity and prostate cancer risk in African men

PURPOSE

African men are disproportionately affected by prostate cancer (PCa). Given the increasing prevalence of obesity in Africa, and its association with aggressive PCa in other populations, we examined the relationship of overall and central obesity with risks of total and aggressive PCa among African men.

METHODS

Between 2016 and 2020, we recruited 2,200 PCa cases and 1,985 age-matched controls into a multi-center, hospital-based case-control study in Senegal, Ghana, Nigeria, and South Africa. Participants completed an epidemiologic questionnaire, and anthropometric factors were measured at clinic visit. Multivariable logistic regression was used to examine associations of overall and central obesity with PCa risk, measured by body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR), respectively.

RESULTS

Among controls 16.4% were obese (BMI ≥ 30 kg/m2), 26% and 90% had WC > 97 cm and WHR > 0.9, respectively. Cases with aggressive PCa had lower BMI/obesity in comparison to both controls and cases with less aggressive PCa, suggesting weight loss related to cancer. Overall obesity (odds ratio: OR = 1.38, 95% CI 0.99-1.93), and central obesity (WC > 97 cm: OR = 1.60, 95% CI 1.10-2.33; and WHtR > 0.59: OR = 1.68, 95% CI 1.24-2.29) were positively associated with D'Amico intermediate-risk PCa, but not with risks of total or high-risk PCa. Associations were more pronounced in West versus South Africa, but these differences were not statistically significant.

DISCUSSION

The high prevalence of overall and central obesity in African men and their association with intermediate-risk PCa represent an emerging public health concern in Africa. Large cohort studies are needed to better clarify the role of obesity and PCa in various African populations.

Development, Evaluation, and Implementation of a Pan-African Cancer Research Network: Men of African Descent and Carcinoma of the Prostate

PURPOSE

Cancer of the prostate (CaP) is the leading cancer among men in sub-Saharan Africa (SSA). A substantial proportion of these men with CaP are diagnosed at late (usually incurable) stages, yet little is known about the etiology of CaP in SSA.

METHODS

We established the Men of African Descent and Carcinoma of the Prostate Network, which includes seven SSA centers partnering with five US centers to study the genetics and epidemiology of CaP in SSA. We developed common data elements and instruments, regulatory infrastructure, and biosample collection, processing, and shipping protocols. We tested this infrastructure by collecting epidemiologic, medical record, and genomic data from a total of 311 patients with CaP and 218 matched controls recruited at the seven SSA centers. We extracted genomic DNA from whole blood, buffy coat, or buccal swabs from 265 participants and shipped it to the Center for Inherited Disease Research (Baltimore, MD) and the Centre for Proteomics and Genomics Research (Cape Town, South Africa), where genotypes were generated using the UK Biobank Axiom Array.

RESULTS

We used common instruments for data collection and entered data into the shared database. Double-entered data from pilot participants showed a 95% to 98% concordance rate, suggesting that data can be collected, entered, and stored with a high degree of accuracy. Genotypes were obtained from 95% of tested DNA samples (100% from blood-derived DNA samples) with high concordance across laboratories.

CONCLUSION

We provide approaches that can produce high-quality epidemiologic and genomic data in multicenter studies of cancer in SSA.

Early-onset sensorineural hearing loss in Lassa fever

Lassa fever (LF) is a viral hemorrhagic disease which affects one-fourth to two million people annually with the fatality rate of about 10,000. It is associated with sensorineural hearing loss (SNHL) usually at the convalescent stage. Recently, cases of SNHL at the acute phase have been reported. This study was done to further investigate the incidence and features of SNHL in acute phase of LF. It is a prospective case-control study of LF patients seen with acute SNHL conducted between July 2007 and April 2009 at Irrua Specialist Teaching Hospital Nigeria. The diagnosis of acute LF was based on the clinical features and detection of IgM antibodies and/or positive Lassa virus-specific reverse transcriptase-polymerase chain reaction using primers S36+ and LVS 339 while SNHL was diagnosed clinically and confirmed with PTA and speech discrimination tests. Patients with other acute febrile illnesses were used as control. Statistical analysis was done using SPSS version 11 and Fisher's exact test while level of significance was set at p < 0.05. Out of the 37 confirmed cases of LF, 5 (13.5%) and none (0%) of the control developed early-onset SNHL (p = 0.03). Forty percent of the cases studied had negative IgM. The audiograms showed involvement at all frequency groups with pure tone average 65-85 dB and the speech discrimination 20-40%. The overall case fatality rate was 27.0%, and for early SNHL cases 60.0% (p > 0.05). The incidence of SNHL in LF infection is about 13.5% and could be a reflection of a worse disease process. There is possibility of direct viral invasion aside immunological reaction as a causative mechanism.

Haematological profile of healthy pregnant women in Ibadan, South-western Nigeria

There is a dearth of information on the reference values for haematological indices particularly according to the relevant trimesters of pregnant women in Nigeria. The objective of this study was to provide reference values for Nigerian pregnant women. The study took place at the Adeoyo Maternity Hospital and the University College Hospital, both in Ibadan. This descriptive study was carried out over a period of 8 months. Subjects were apparently healthy pregnant women that satisfied the inclusion and exclusion criteria. The mean values (and 95% confidence intervals, CI) of haematological indices were as follows -- First trimester: Haemoglobin (Hb) 112.44 (101.64 - 123.25) g/l, haematocrit (hct) 35 (32 - 38)%, WBC 5.488 (4.025 - 6.950) x 10(9)/l and platelet counts 227.56 (165.21 - 289.90) x 10(9)/l;Second trimester: Hb 100.39 (97.85 - 102.92) g/l, hct 29.3 (28.5 - 30.1)%, WBC 6.57 (6.19 - 6.95) x 10(9)/l, platelet count 229.56 (211.86 - 247.26); and the Third trimester: Hb 98.06 (96.12 - 100.00) g/l, hct 29.4 (28.7 - 29.9)%, WBC 6.92 (6.53 - 7.30), platelet count 186.52 (177.67 - 195.38) x 10(9)/l. These results were compared with those of 52 non-pregnant age matched women volunteers as controls whose mean haematological indices and 95% CI were: Hb 120.51 (116.61 - 124.41) g/l, hct 36 (25 - 48)%, WBC 5.28 (2.9 - 8.7) x 10(9), platelet count 330.87 (176 - 538) x 10(9)/l. The following haematological indices: WBC, platelet counts, RBC, PCT, and PDW, of women between the trimesters showed statistical significance (p value < 0.001 in each case). The WBC is inversely proportional to the PCT and the MCV in the pregnant women was slightly raised. In this study, pregnancy is characterised by lowest values of haemoglobin parameters in trimester three and there are statistically significant differences between the WBC, platelet counts, RBC, PCT, and PDW of women between the three trimesters.