Page 2 of 24 FirstFirst 123412 ... LastLast
Results 16 to 30 of 358

Thread: Advanced Maternal Age Associated with AIS?

  1. #16
    Join Date
    Aug 2009
    Posts
    1,164
    One of the studies makes the link directly, but increased maternal age is linked to other factors (like increased socioeconomic status). That makes it very difficult to differentiate pre-birth environmental factors from post-birth environmental factors.

    Maybe wealthier (and usually older) moms are slathering on the sunscreen, thus leading to Vitamin D deficiency. Or a thousand other possibilities.

    It would seem to point to something other than pure genetics, though.

    Jess, if it makes you feel better, autism is often linked to the *father's* age

  2. #17
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    http://www.cell.com/AJHG/retrieve/pii/S0002929707604856

    Adolescent idiopathic scoliosis (AIS) is one of the most common orthopedic disorders, affecting up to 4% of schoolchildren worldwide.
    Given that the average maternal age varies between different countries, the relative constancy of the worldwide rate argues that it is almost extirely strictly genetics (and that humans are an extremely homogeneous species).

    That is not to say there are small, signals in the noise. But they are numbers and perhaps you can measure them but they mean virtually nothing of the scheme of things.

    Perspective always.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  3. #18
    Join Date
    Mar 2009
    Location
    Arizona
    Posts
    1,058
    Patients who were born to mothers who were twenty-seven years old or more had a mean curve of 35.2 degrees, which was significantly greater (p = 0.02) than that of patients whose mothers were younger than twenty-seven years, who had a mean curve of 30.4 degrees
    When risk starts increasing at the age of 27 that's a red flag for exposure to something in the environment. That's a healthy age to have children.

    For example the risk for cerebral palsy starts to go up after the age of 25 (wow!) and it's clearly an environmentally triggered disorder.

    Chorioamnionitis and cerebral palsy in term and near-term infants.

    DESIGN, SETTING, AND PATIENTS: Case-control study nested within a cohort of 231,582 singleton infants born at 36 or more weeks' gestation between January 1, 1991, and December 31, 1998, in the Kaiser Permanente Medical Care Program, a managed care organization providing care for more than 3 million residents of northern California.

    RESULTS: Independent risk factors identified in multiple logistic regression included chorioamnionitis (OR, 4.1; 95% CI, 1.6-10.1), intrauterine growth restriction (OR, 4.0; 95% CI, 1.3-12.0), maternal black ethnicity (OR, 3.6; 95% CI, 1.4-9.3), maternal age older than 25 years (OR, 2.6; 95% CI, 1.3-5.2), and nulliparity (OR, 1.8; 95% CI, 1.0-3.0). The population-attributable fraction of chorioamnionitis for CP is 11%.
    In case you were wondering Chorioamnionitis is inflammation caused by a bacterial infection.
    Chorioamnionitis is an inflammation of the fetal membranes (amnion and chorion) due to a bacterial infection.
    Trauma can trigger CP but so can many common, infectious diseases like herpes.

    It's safe to assume that when illness strikes the children of young mothers environment is to blame 99% of the time.
    Last edited by Dingo; 01-29-2011 at 07:43 PM.

  4. #19
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    If it is like Down syndrome which also follows the pattern of increased risk with increased maternal age then it is strictly genetic with no evidence whatsoever for environmental factors...

    http://en.wikipedia.org/wiki/Down_syndrome

    Current research (as of 2008) has shown that Down syndrome is due to a random event during the formation of sex cells or pregnancy. There has been no evidence that it is due to parental behavior (other than age) or environmental factors.
    Aging of gametes seems like the most likely explanation as it is for Down syndrome.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  5. #20
    Join Date
    Mar 2009
    Location
    Arizona
    Posts
    1,058
    Ya know maybe it's good that I didn't know the risk for AIS increased at age 27. That's such a red flag for environment that I would have been even cockier over the past couple of years. (shudder)
    8-)
    Last edited by Dingo; 01-29-2011 at 07:43 PM.

  6. #21
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    The finding that the incidence of AIS correlates with maternal age is further proof of what is accepted already that it is a genetic condition. That and the relatively constant worldwide rate plus the empirical evidence from Ward, Ogilvie et al. are independent, mutually buttressing pieces of evidence that explain why AIS is accepted as a genetic disorder.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  7. #22
    Join Date
    Aug 2009
    Posts
    1,164
    Quote Originally Posted by Pooka1 View Post
    Given that the average maternal age varies between different countries, the relative constancy of the worldwide rate argues that it is almost extirely strictly genetics (and that humans are an extremely homogeneous species).
    I'm not sure the wording "up to 4% worldwide" indicates a steady worldwide rate. It could mean that it affects 20% in one country and .1% in another, and so on. Or, it could mean just exactly what it seems to mean - that 4% is the upper rate, and rates in other countries are below that. When dealing with small percentages, little variations are critical. 52% and 54% are just about the same. 2% and 4% are not.

    I've found it very difficult to locate comparisons of scoliosis rates between countries or over time.

  8. #23
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    Quote Originally Posted by hdugger View Post
    I'm not sure the wording "up to 4% worldwide" indicates a steady worldwide rate. It could mean that it affects 20% in one country and .1% in another, and so on. Or, it could mean just exactly what it seems to mean - that 4% is the upper rate, and rates in other countries are below that. When dealing with small percentages, little variations are critical. 52% and 54% are just about the same. 2% and 4% are not.

    I've found it very difficult to locate comparisons of scoliosis rates between countries or over time.
    If the incidence rate varied wildly between countries then that would be very good evidence of an environmental trigger. This is not my field but I can say I have not come across a single reliable reference even mentioning that.

    IS is accepted a genetic disorder. The question is how is it inherited, not if it is inherited.

    Complex, polygenetic modes of inheritance could well resemble germ theory to a bunny but not to an expert in the field.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  9. #24
    Join Date
    Aug 2009
    Posts
    1,164
    Slipped posts by Dingo and Pooka proving, once again, that science is all in the interpretation

  10. #25
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    Quote Originally Posted by hdugger View Post
    Slipped posts by Dingo and Pooka proving, once again, that science is all in the interpretation
    Yeah but Dingo's interpretation varies from that of the experts in the field. Key difference there.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  11. #26
    Join Date
    May 2009
    Posts
    3,745

    hi guys...i just think it is a lot of noise about little substance so far...
    i want to see big numbers of women in studies...i say again, i don't understand why 2000 or so women over age 27, who give birth in hospitals, cannot be followed for that one single factor...scoliosis in their kids, or no scoliosis...and in nations besides the USA, too...177 patients is not a big enough study...and it needs to be replicated in many populations, in many countries...

    i do not have a personal stake in this issue, so it wouldn't "make me feel better" one way or another....i just think it is adding worry to young women when it is not justified...i understand the researchers are saying it is higher risk, and not all children of "older" mothers...but what percentage of "older" mothers in what countries...? is it universal, regardless of where the study is conducted?

    also...if environment is a cause, or contributor..is it something in certain countries? just the USA and Australia? Britain?
    what happens in other countries.....India, New Zealand, Israel, etc...is it a certain toxin common in only some countries...or something specific to certain regions of the earth..??

    27 is such a weird number for a cut off....it was always considered to be still a healthy age for having kids, as Dingo mentioned...


    jess
    Last edited by jrnyc; 01-29-2011 at 08:39 PM.

  12. #27
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    Quote Originally Posted by jrnyc View Post
    27 is such a weird number for a cut off....it was always considered to be still a healthy age for having kids, as Dingo mentioned...
    That number is almost certainly just an artifact of slicing and dicing the data until they maximized the largest difference between data bins. It is similar to how Katz et al., sliced and diced and binned the data until they found a cutoff which maximized the difference between groups. If they plotted and showed all the data this would become obvious. They didn't do that although they only had 100 points. There is likely no step function at 12 hours in Katz et al. and there is likely no step function at 27 years old in these data.

    It is more robust to have a hypothesis going and seeing if the data support it rather than doing this post hoc approach of slicing/dicing data it seems.

    If the study was repeated, the chances of the number coming up 27 would likely not be great.
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  13. #28
    Join Date
    Jan 2008
    Location
    NC
    Posts
    9,187
    With the amount of scientific fact denial going on here we might as well be in Dayton, TN in 1925...
    Sharon, mother of identical twin girls with scoliosis

    No island of sanity.

    Question: What do you call alternative medicine that works?
    Answer: Medicine


    "We are all African."

  14. #29
    Join Date
    Mar 2009
    Location
    Arizona
    Posts
    1,058
    hdugger

    I'm not sure the wording "up to 4% worldwide" indicates a steady worldwide rate.
    You are correct. The rate of Scoliosis probably varies by country and even within a given country. For instance Schizophrenia strikes people in cities at a far greater rate than the country.

    Urban birth and risk of schizophrenia: a worrying example of epidemiology where the data are stronger than the hypotheses.

    There is robust and consistent evidence from epidemiological studies showing that urban birth is associated with an increased risk of developing schizophrenia. Evidence suggests that this exposure may be associated with a sizeable proportion of cases. To date the candidate exposures underlying the urban birth risk factor have included infectious agents, low prenatal vitamin D, toxins associated with pollution, and stress. However, in general, the hypotheses proposed to explain the urban birth risk factor have been unsatisfying. In light of the general trend towards increasing urbanization, it is feasible that the attributable fraction of schizophrenia associated with urban birth may increase. The psychiatric research community should have a sense of urgency in exploring the mechanisms linking urban birth and risk of schizophrenia.
    Disease also goes up and down over time.
    Scoliosis epidemic in Jamaica

    Thus, in Jamaica, there has been almost an epidemic of idiopathic scoliosis which started around 1963 and began to fall off after 1982.
    Anybody who claims that Scoliosis hits the same number of people in every country and that the rate never varies is making things up. Pretty much nothing works like that and I doubt there is any scientific evidence to support such a statement.
    Last edited by Dingo; 01-29-2011 at 09:35 PM.

  15. #30
    Join Date
    Mar 2009
    Location
    Arizona
    Posts
    1,058
    jrnyc

    27 is such a weird number for a cut off....it was always considered to be still a healthy age for having kids, as Dingo mentioned...
    Assuming those studies are correct (and I'd love to see more) that's a dead giveaway for environment. 27 year old women are still in their prime. My hunch is that this indicates an exposure. The longer a woman lives the more chance she has to run into something dangerous. That's almost certainly why the risk for Cerebral Palsy goes up at age 25 which is otherwise a very healthy age.

    BTW even if the rate didn't begin to climb until age 35 it would still indicate environment. But the fact that the rate climbs at such a young age is telling.
    Last edited by Dingo; 01-29-2011 at 09:38 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •