comparative analysis of parameters of human senescence
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Comparative analysis of parameters of human senescence. Natalia S. Gavrilova Leonid A. Gavrilov Center on Aging, NORC/University of Chicago, 1155 East 60th Street, Chicago, IL 60637. - PowerPoint PPT PresentationTRANSCRIPT
Comparative analysis of parameters of human
senescence
Natalia S. GavrilovaLeonid A. Gavrilov
Center on Aging, NORC/University of Chicago, 1155 East 60th Street, Chicago, IL 60637
The idea of this study has been suggested by Fedor Severin in order to test whether aging is programmed or not.
The idea of this study is to compare variability for traits, which are known to be determined by the developmental program (such as ages at sexual maturity) with variability of traits related to aging (such as ages at menopause and death).
One of the arguments used by the opponents of programmed aging is a too high variation in individual lifespans compared to the observed variation of programmed events (such as the age of sexual maturation). The main goal of this study was to
test the validity of this argument.
Measures of variability Absolute measure – standard
deviation For distribution of lifespan,
demographers often calculate standard deviation at age 10 – SD10 (Edwards & Tuljapurkar 2005).
Relative measure – coefficient of variation. Equals the standard deviation divided by the mean
Historical Changes in Mortality Swedish Females
Age0 20 40 60 80 100
Log
(Haz
ard
Rat
e)
0.0001
0.001
0.01
0.1
1
1925196019801999
Data source: Human Mortality Database
Age at onset of menarche is an example of characteristic determined by developmental program
Age at onset of menarche was declining in the XX century. Norway data.Source: "Age of Menarche in Norway [Chart]," in Children and Youth in History, Item #207, http://chnm.gmu.edu/cyh/primary-sources/207 (accessed February 13, 2010). Annotated by Stephen Robertson
Similar results are obtained for Korean girls
Source: Age at menarche in a Korean population: secular trends and influencing factors. Geum Joon Cho et al. EUROPEAN JOURNAL OF PEDIATRICS 169 1 89-94 JAN 2010
Declining of the menarche age decelerated in developed countries now. Helm P, Grolund L (1998) A halt in
the secular trend towards earlier menarche in Denmark. Acta Obstet Gynecol Scand 77:198–200
Similar results obtained for Finland and Iceland
Mean age 13.00 years, SD 1.15 years for Danish girls in 1996
What studies tell us about the variation of menarche age?
Mean age at menarche, its standard deviation and coefficient of variation for European women (The EPIC Study)
Country Birth years Mean age at menarche (SD)
Coefficient of variation (CV)
France 1921-1956 12.84 (1.40) 10.9%Italy 1920-1962 12.54 (1.46) 11.6%Spain 1925-1961 12.91 (1.56) 12.1%United Kingdom 1918-1963 12.89 (1.54) 12.0%Greece 1920-1964 13.19 (1.52) 11.5%
Source: Onland-Moret et al., American Journal of Epidemiology 2005 162(7):623-632
Mean age at menarche, its standard deviation and coefficient of variation for European women (continue)Country Birth years Mean age at
menarche (SD)
Coefficient of variation (CV)
The Netherlands 1924-1962 13.28 (1.56) 11.8%Germany 1926-1963 13.16 (1.48) 11.2%Sweden 1923-1950 13.59 (1.41) 10.4%Denmark 1929-1947 13.56 (1.53) 11.3%Greece 1920-1964 13.19 (1.52) 11.5%
Source: Onland-Moret et al., American Journal of Epidemiology 2005 162(7):623-632
Age at menarche in other countries Iran: Mean age (SD) in the urban
areas was 12.4 (1.1) years and in rural areas it was 12.6 (1.1) years (Delavar and Hajian-Tilaki, 2008)
Korea: Mean age at menarche of girls born between 1986 and 1995 was 13.10 (1.49) (Cho et al. , 2010)
What about boys? Third National Health and Nutrition
Examination Survey (NHANES III) Sexual maturity stages based on the
recommendations of Tanner were assigned to each maturity indicator
Pubic hair development using stages from 1 (immaturity) to 5 (complete maturity)
Genitalia development using stages from 1 (immaturity) to 5 (complete maturity)
Mean age (SD) of some characteristics of sexual maturation for U.S. boys (NHANES study)Characteristic Non-Hispanic
whitesNon-Hispanic blacks
Mexican Americans
Pubic hair development, stage 5
16.84 (1.50) 16.67 (1.23) 17.14 (1.45)
Genitalia development, stage 5
16.64 (1.64) 16.42 (1.43) 16.85 (1.92)
Source: Sun et al., PEDIATRICS, 2002, 110: 911-919
Age at natural menopause as a marker of reproductive aging
Mean age (SD) at natural menopause
Population Mean age (SD) at
menopause, years
Source
South Korean women 46.9 (4.9) Hong et al., MATURITAS, 2007
Viennese women aged 47 to 68
49.2 (3.6) Kirchengast et al., International Journal of Anthropology , 1999
Mexico: Puebla Mexico city
46.7 (4.77)46.5 (5.00)
Sievert, Hautaniemi, Human Biology, 2003
Black women in South Africa: rural urban
49.5 (4.7)48.9 (4.2)
Walker et al., International Journal of Obstetrics & Gynaecology, 2005
Our results using the MIDUS study
National survey conducted in 1994/95 Americans aged 25-74
core national sample (N=3,485) city oversamples (N=957)
Additional samples: twins, siblings Subsample used in this study: women having
natural menopause (no surgeries affecting the age at menopause) aged 60-74
A 30-40 minute telephone survey A 114 page mail surveyNumber of respondents: 4,242 Number of respondents: 3,690
Women Aged 25-74 (n=2,087)AGE 25-54 68.8 55-64 19.8 65-74 11.4RACE/ETHNICITY White 86.9 African-American 7.7 Other 8.9RELATIONSHIP STATUS Married 54.2 Other intimate relationship 4.7
MIDUS SAMPLE POPULATION DISTRIBUTIONS (%)
DISTRIBUTION OF AGE AT MENARCHE IN THE MIDUS SAMPLE
0.1
.2.3
Den
sity
8 10 12 14 16 18age of menarche
DISTRIBUTION OF AGE AT MENOPAUSE IN THE MIDUS SAMPLE
0.0
2.0
4.0
6.0
8D
ensi
ty
20 30 40 50 60 70age of menopause
DISTRIBUTION OF AGE AT DEATH, SWEDISH FEMALES, 1995
0.0
1.0
2.0
3.0
4D
ensi
ty
0 50 100age
Data source: Human Mortality Database
Variation for characteristics of human aging and development
Characteristic
Mean age (SD) years
Coefficient of
variation
Source
Age at onset of menarche
12.9 (1.6) 12.4% MIDUS data
Age at onset of menopause
49.7 (5.2) 10.5% MIDUS data
Age at death 78.7 (16.1)
20.5% USA, women, 1995. Human mortality database
Variation of age at onset of menarche and age at death (in 2005)Country Mean age
(SD) for onset of
menarche
CV%
Mean age (SD) at death
CV%
France 12.84 (1.40) 10.9 83.3 (13.8)
16.6
Italy 12.54 (1.46) 11.6 83.3 (13.1)
15.7
Sweden 13.59 (1.41) 10.4 82.3 (12.9)
15.7
UK 12.89 (1.54) 12.0 80.2 (14.0)
17.5
USA 12.9 (1.60) 12.4 78.7 (16.1)
20.5
Variation of age at onset of menarche and age at death (in 2005) after 10 years
Country Mean age (SD) for onset of
menarche
CV%
Mean age
(SD10) at death
after 10
CV10%
France 12.84 (1.40) 10.9 83.7 (12.7)
15.2
Italy 12.54 (1.46) 11.6 83.7 (11.9)
14.2
Sweden 13.59 (1.41) 10.4 82.5 (12.0)
14.5
UK 12.89 (1.54) 12.0 81.2 (12.6)
15.5
USA 12.9 (1.60) 12.4 79.4 (14.3)
18.0
Mean Values and Standard Deviations for Human Developmental Characteristics
Conclusions Standard deviations for age at onset
of menarche are about 10 times lower than standard deviations for ages at death
Coefficients of variation for ages at onset of menarche and ages at death for contemporary populations are of the same order of magnitude
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