Browsing by Author "Isaac Kisiangani"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Meta-analysis of sub-Saharan African studies provides insights into genetic architecture of lipid traits
    (2022-05-11) Ananyo Choudhury; Jean-Tristan Brandenburg; Tinashe Chikowore; Dhriti Sengupta; Palwende Romuald Boua; Nigel J. Crowther; Godfred Agongo; Gershim Asik; F. Xavier Gómez-Olivé; Isaac Kisiangani; Eric Maimela; Matshane Masemola-Maphutha; Lisa K. Micklesfield; Engelbert A. Nonterah; Shane A. Norris; Hermann Sorgho; Halidou Tinto; Stephen Tollman; Sarah E. Graham; Cristen J. Willer; AWI-Gen study; H3Africa Consortium; Scott Hazelhurst; Michèle Ramsay
    Genetic associations for lipid traits have identified hundreds of variants with clear differences across European, Asian and African studies. Based on a sub-Saharan-African GWAS for lipid traits in the population cross-sectional AWI-Gen cohort (N = 10,603) we report a novel LDL-C association in the GATB region (P-value=1.56 × 10−8). Meta-analysis with four other African cohorts (N = 23,718) provides supporting evidence for the LDL-C association with the GATB/FHIP1A region and identifies a novel triglyceride association signal close to the FHIT gene (P-value =2.66 × 10−8). Our data enable fine-mapping of several well-known lipid-trait loci including LDLR, PMFBP1 and LPA. The transferability of signals detected in two large global studies (GLGC and PAGE) consistently improves with an increase in the size of the African replication cohort. Polygenic risk score analysis shows increased predictive accuracy for LDL-C levels with the narrowing of genetic distance between the discovery dataset and our cohort. Novel discovery is enhanced with the inclusion of African data.
  • Thumbnail Image
    Item
    Physical Activity and Its Association With Body Mass Index: A Cross-Sectional Analysis in Middle-Aged Adults From 4 Sub-Saharan African Countries
    (2023-08-17) Monica Mut; Lisa J. Ware; Lisa K. Micklesfield; Michele Ramsay; Godfred Agongo; Palwende R. Boua; Isaac Kisiangani; Ian Cook; Francesc Xavier Go´mez-Olivé; Nigel J. Crowther; Chodziwadziwa Kabudula; Shane A. Norris; Tinashe Chikowore
    Background: This study aimed to explore association of self-reported physical activity domains of work, leisure, and transport-related physical activity and body mass index (BMI) in 9388 adult men and women from the Africa-Wits-INDEPTH partnership for Genomic (AWI-Gen) study in Africa. Africa-Wits-INDEPTH partnership for Genomic is a large, population-based cross-sectional cohort with participants from 6 sites from rural and urban areas in 4 sub-Saharan African countries. Methods: A sex-stratified meta-analysis of cross-sectional data from men and women aged 29–82 years was used to assess the association of physical activity with BMI. Results: Overall, meeting physical activity guidelines of at least 150 minutes per week was associated with 0.82 kg/m2 lower BMI in men (β = −0.80 kg/m2 ; 95% confidence interval [CI], −1.14 to −0.47) and 0.68 kg/m2 lower BMI in women (β = −0.68 kg/m2 ; 95% CI, −1.03 to −0.33). Sex and site-specific differences were observed in the associations between physical activity domains and BMI. Among those who met physical activity guidelines, there was an inverse association between transport-related physical activity and BMI in men from Nanoro (Burkina Faso) (β = −0.79 kg/m2 ; 95% CI, −1.25 to −0.33) as well as work-related physical activity and BMI in Navrongo men (Ghana) (β = −0.76 kg/m2 ; 95% CI, −1.25 to −0.27) and Nanoro women (β = −0.90 kg/m2 ; 95% CI, −1.44 to −0.36). Conclusions: Physical activity may be an effective strategy to curb rising obesity in Africa. More studies are needed to assess the impact of sex and geographic location-specific physical activity interventions on obesity.