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Leveraging ongoing research to evaluate the health impacts of South Africa's salt reduction strategy: a prospective nested cohort within the WHO-SAGE multicountry, longitudinal study

Journal Article


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Abstract


  • Introduction: Attempting to curb the rising epidemic

    of hypertension, South Africa implemented legislation

    in June 2016 mandating maximum sodium levels in a

    range of manufactured foods that contribute

    significantly to population salt intake. This natural

    experiment, comparing two African countries with and

    without salt legislation, will provide timely information

    on the impact of legislative approaches addressing the

    food supply to improve blood pressure in African

    populations. This article outlines the design of this

    ongoing prospective nested cohort study.

    Methods and analysis: Baseline sodium intake was

    assessed in a nested cohort of the WHO Study on

    global AGEing and adult health (WHO-SAGE) wave 2

    (2014–2015), a multinational longitudinal study on the

    health and well-being of adults and the ageing process.

    The South African cohort consisted of randomly

    selected households (n=4030) across the country. Spot

    and 24-hour urine samples are collected in a random

    subsample (n=1200) and sodium, potassium,

    creatinine and iodine analysed. Salt behaviour and

    sociodemographic data are captured using face-to-face

    interviews, alongside blood pressure and

    anthropometric measures. Ghana, the selected control

    country with no formal salt policy, provided a nested

    subsample (n=1200) contributing spot and 24-hour

    urine samples from the SAGE Ghana cohort (n=5000).

    Follow-up interviews and urine collection (wave 3) in

    both countries will take place in 2017 (postlegislation)

    to assess change in population-level sodium intake and

    blood pressure.

    Ethics and dissemination: SAGE was approved by

    the WHO Ethics Review Committee (reference number

    RPC149) with local approval from the North-West

    University Human Research Ethics Committee and

    University of the Witwatersrand Human Research

    Ethics Committee (South Africa), and University of

    Ghana Medical School Ethics and Protocol Review

    Committee (Ghana). The results of the study will be

    published in peer-reviewed international journals,

    presented at national and international conferences,

    and summarised as research and policy briefs.

Authors


  •   Charlton, Karen E.
  •   Ware, Lisa J. (external author)
  •   Menyanu, Elias (external author)
  •   Biritwum, Richard Berko. (external author)
  •   Naidoo, Nirmala (external author)
  •   Pieterse, Chine (external author)
  •   Madurai, Savathree (Lorna) (external author)
  •   Baumgartner, Jeannine (external author)
  •   Asare, George A. (external author)
  •   Thiele, Elizabeth (external author)
  •   Schutte, Aletta E. (external author)
  •   Kowal, Paul (external author)

Publication Date


  • 2016

Citation


  • Charlton, K., Ware, L., Menyanu, E., Biritwum, R. Berko., Naidoo, N., Pieterse, C., Madurai, S., Baumgartner, J., Asare, G. A., Thiele, E., Schutte, A. E. & Kowal, P. (2016). Leveraging ongoing research to evaluate the health impacts of South Africa's salt reduction strategy: a prospective nested cohort within the WHO-SAGE multicountry, longitudinal study. BMJ Open, 6 e013316-1-e013316-11.

Scopus Eid


  • 2-s2.0-85001889671

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=5201&context=smhpapers

Ro Metadata Url


  • http://ro.uow.edu.au/smhpapers/4177

Start Page


  • e013316-1

End Page


  • e013316-11

Volume


  • 6

Abstract


  • Introduction: Attempting to curb the rising epidemic

    of hypertension, South Africa implemented legislation

    in June 2016 mandating maximum sodium levels in a

    range of manufactured foods that contribute

    significantly to population salt intake. This natural

    experiment, comparing two African countries with and

    without salt legislation, will provide timely information

    on the impact of legislative approaches addressing the

    food supply to improve blood pressure in African

    populations. This article outlines the design of this

    ongoing prospective nested cohort study.

    Methods and analysis: Baseline sodium intake was

    assessed in a nested cohort of the WHO Study on

    global AGEing and adult health (WHO-SAGE) wave 2

    (2014–2015), a multinational longitudinal study on the

    health and well-being of adults and the ageing process.

    The South African cohort consisted of randomly

    selected households (n=4030) across the country. Spot

    and 24-hour urine samples are collected in a random

    subsample (n=1200) and sodium, potassium,

    creatinine and iodine analysed. Salt behaviour and

    sociodemographic data are captured using face-to-face

    interviews, alongside blood pressure and

    anthropometric measures. Ghana, the selected control

    country with no formal salt policy, provided a nested

    subsample (n=1200) contributing spot and 24-hour

    urine samples from the SAGE Ghana cohort (n=5000).

    Follow-up interviews and urine collection (wave 3) in

    both countries will take place in 2017 (postlegislation)

    to assess change in population-level sodium intake and

    blood pressure.

    Ethics and dissemination: SAGE was approved by

    the WHO Ethics Review Committee (reference number

    RPC149) with local approval from the North-West

    University Human Research Ethics Committee and

    University of the Witwatersrand Human Research

    Ethics Committee (South Africa), and University of

    Ghana Medical School Ethics and Protocol Review

    Committee (Ghana). The results of the study will be

    published in peer-reviewed international journals,

    presented at national and international conferences,

    and summarised as research and policy briefs.

Authors


  •   Charlton, Karen E.
  •   Ware, Lisa J. (external author)
  •   Menyanu, Elias (external author)
  •   Biritwum, Richard Berko. (external author)
  •   Naidoo, Nirmala (external author)
  •   Pieterse, Chine (external author)
  •   Madurai, Savathree (Lorna) (external author)
  •   Baumgartner, Jeannine (external author)
  •   Asare, George A. (external author)
  •   Thiele, Elizabeth (external author)
  •   Schutte, Aletta E. (external author)
  •   Kowal, Paul (external author)

Publication Date


  • 2016

Citation


  • Charlton, K., Ware, L., Menyanu, E., Biritwum, R. Berko., Naidoo, N., Pieterse, C., Madurai, S., Baumgartner, J., Asare, G. A., Thiele, E., Schutte, A. E. & Kowal, P. (2016). Leveraging ongoing research to evaluate the health impacts of South Africa's salt reduction strategy: a prospective nested cohort within the WHO-SAGE multicountry, longitudinal study. BMJ Open, 6 e013316-1-e013316-11.

Scopus Eid


  • 2-s2.0-85001889671

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=5201&context=smhpapers

Ro Metadata Url


  • http://ro.uow.edu.au/smhpapers/4177

Start Page


  • e013316-1

End Page


  • e013316-11

Volume


  • 6