A life history perspective on size health and adult mortality in the gambia
Download
1 / 19

A life history perspective on size, health and adult mortality in the Gambia - PowerPoint PPT Presentation


  • 98 Views
  • Uploaded on

A life history perspective on size, health and adult mortality in the Gambia. Rebecca Sear London School of Economics. Life history theory and demography. Life history is concerned with allocation of energy over the life course

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' A life history perspective on size, health and adult mortality in the Gambia' - oneida


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
A life history perspective on size health and adult mortality in the gambia

A life history perspective on size, health and adult mortality in the Gambia

Rebecca Sear

London School of Economics


Life history theory and demography
Life history theory and demography mortality in the Gambia

  • Life history is concerned with allocation of energy over the life course

  • How do organisms solve problem of adaptively allocating energy between growth, body subsistence and repair, and reproduction?

  • Demography a key component of LHT – both a constraint on, and an outcome of, life history decisions


Adult mortality and resource availability
Adult mortality and resource availability mortality in the Gambia

  • This study investigates relationship between adult mortality and resource availability

  • Measures of resources availability

    • Height

    • BMI

    • Haemoglobin (Hb)


Height
Height mortality in the Gambia

  • Height: measure of past investment in growth

    • Previous research:

      • Human studies (height):

        • height usually found to be negatively correlated with mortality

        • but recent evidence suggests mortality higher in tall people for certain causes

      • Animal studies (size):

        • caloric restriction increases longevity

        • costs of fast growth


Bmi hb
BMI & Hb mortality in the Gambia

  • BMI & Hb: measures of current body condition

    • Mortality should be inversely related to both BMI and Hb but

      • What is the shape of the relationship?

      • Does this relationship differ between women and men?

    • Previous (human) studies suggest a non-linear relationship between BMI and mortality


Analysis
Analysis mortality in the Gambia

  • Analysis of adult (21+ years) mortality by:

    • Height

    • BMI

    • Haemoglobin level

  • Investigating both whether there is a relationship, and the shape of the relationship

  • For both women and men


Data mortality in the Gambia

  • Data collected 1950-74

  • 4 rural villages

  • Demographic data collected continuously

  • Anthropometric surveys conducted (at least) annually


Adult anthropometrics
Adult anthropometrics mortality in the Gambia


Height and age
Height and age mortality in the Gambia


Bmi and age
BMI and age mortality in the Gambia


Hb and age
Hb and age mortality in the Gambia


Adult mortality
Adult mortality mortality in the Gambia


Methods
Methods mortality in the Gambia

  • Discrete-time event-history analysis on probability of adult death (21+ years)

  • Separate models for women and men

  • Anthropometric variables entered as time dependent

  • Controlled for birth cohort


Results
Results mortality in the Gambia


Height and mortality
Height and mortality mortality in the Gambia


Bmi and mortality
BMI and mortality mortality in the Gambia


Hb and mortality
Hb and mortality mortality in the Gambia


Conclusions i
Conclusions I mortality in the Gambia

  • Height:

    • matters for female mortality – though relationship not linear

    • Why not for men?

  • Measures of current body condition significantly correlated with mortality for both sexes

    • High BMI increases mortality (costs of fat storage?), but low BMI more important

    • Hb important for both sexes, especially women (maternal mortality?)


Conclusions ii
Conclusions II mortality in the Gambia

  • Clearly, there is variation in adult mortality by resource availability

  • Though these relationships tend not to be linear

  • Current health/body condition matters for both sexes, height only for women

    • growing tall has costs for women (or linked to greater reproductive effort of tall women?), but apparently not for men?

  • Influence of genetic factors?


ad