Studie som tilbakeviser link mellom MMR og autisme

[Drømmemagen]

http://www.bmj.com/cgi/content/abstract/324/7334/393

[Helseinterressert]

Nok en studie som er designet for å feile. Istedet for å se om det er like mye autisma blant uvaksinerte (totalt uvaksinerte) ser man kun på MMR vaksinen. Hmm, lurer på hvorfor?

 

Hvorfor var det kun 3 tilfeller av autister blant Amish folket som har rett til å la seg avstå fra vaksiner når de skulle hatt ca 130 statistisk sett? Disse 3 var imidlertid vaksinerte av ulike grunner...

 

Finnes det en eneste autist blant de tusener, kanskje millioner av uvaksinerte i den vestlige verden?

[Drømmemagen]

Hvor har du det fra at Amish-folket ikke lar seg vaksinere? Vanskelig å følge med når du ikke oppgir kilder, men antar at det er Dan Olmsteds "bevis" du henviser til?

 

Anser disse som litt mer seriøse (du burde virkelig finne deg andre kilder enn Fritt helsevalg og Whale):

http://autism-news-beat.com/?p=29

http://www.medpagetoday.com/Neurology/Seizures/2954

[Helseinterressert]

Bintang,

 

Hva med denne da? En studie med over 500 uvaksinerte hvor det er mindre astma og allergi blant de uvaksinerte enn hos vaksinerte? :

 

http://www.ncbi.nlm.nih.gov/pubmed/15805992?dopt=Abstract

[Drømmemagen]

Endelig en ordentlig referanse; well done

 

Dette er absolutt en interessant artikkel og vel verdt mer forskning. Forfatterne konkluderer med at: "Parents who refuse vaccinations reported less asthma and allergies in their unvaccinated children. Although this relationship was independent of measured confounders, it could be due to differences in other unmeasured lifestyle factors or systematic bias. Further research is needed to verify these results and investigate which exposures are driving the associations between vaccination refusal and allergic disease. The known benefits of vaccination currently outweigh the unproved risk of allergic disease".

 

De påpeker imidlertid at det kan eksistere andre confounders enn det de har tatt høyde for, samt at det kan ha forekommet systematisk bias.

 

De understreker også til slutt at de kjente fordelene med vaksinering er større enn den ubeviste risikoen for allergiske sykdommer.

 

Med andre ord, artikkelen stiller et interessant spørsmål det er verd å følge opp, men jeg, i likhet med artikkelens forfattere, finner ikke på det nåværende tidspunkt noen grunn til å endre mitt standpunkt til vaksiner på basis av dette.

 

 

[Drømmemagen]

Fra samme artikkel som ovenfor:

"The prevalence of asthma was 20.3%, 11.8%, and 15%

among fully vaccinated, partially vaccinated, and ever-vaccinated

children, respectively. Because of the high prevalence of asthma

among fully vaccinated children, we hypothesized that NVIC

member families with fully vaccinated children might be more likely

to respond to the survey if their children had asthma. If true asthma

prevalence among fully vaccinated children in the NVIC was 15%,

then there could be a response bias as high as 30%. Differential

misclassification was also possible because vaccine-refusing families

were more likely to use alternative health care and therefore might not

receive diagnoses. Similarly, families that vaccinate despite concerns

might be less tolerant of symptoms and more likely to seek diagnosis.

For example, the children of vaccine refusers who reported current

wheezing were 2.6 times less likely than wheezing vaccinated

children to report an asthma diagnosis."

[Drømmemagen]

Mer fra samme artikkel:

 

"The analyses adjusted

for measured confounders or estimates of bias

but not both. Complete adjustment for unmeasured

confounders could, potentially, eliminate the observed

associations between vaccines and self-reported allergic

disease."

 

Men, det er verdt å merke seg:

"Despite these concerns, there are several reasons not to

dismiss completely all study findings." Ytterligere forskning burde derfor gjennomføres.

 

Fra artikkelens konklusjon:

"Although 280 children and youths died from asthma

in 2001,26 before vaccination, 11,000 children died and

50,000 children were seriously affected by diseases like

measles, whooping cough, diphtheria, and polio every

year in the United States.27 If vaccination rates decrease,

these diseases will return; none of the vaccinepreventable

diseases are eradicated. For parents of

children at high risk for asthma, these data do not

indicate that refusing vaccines will decrease their

child’s risk of disease. Other parents should remember

that vaccines prevent serious and deadly diseases, and

the known benefits of vaccination clearly outweigh this

hypothetical risk.

 

These data are limited by potential biases inherent in the

population studied, and findings need to be replicated in

a more representative group before inferences can be

drawn. Further studies should include investigating the

variety of alternative health behaviors in this population

and examine the safety of current vaccine schedules and

adjuvants. Basic laboratory research into the effect of

vaccination on the developing immune system could

improve our understanding of both vaccine immunology

and asthma cause.

 

In summary, this study suggests that low-risk children

in families that refuse vaccination are less likely to report

asthma and other allergic symptoms. Universal vaccination

remains fundamental to the protection of individual

and public health. Policy implications must await additional

studies that more clearly define the relevant health

behaviors and identify the biologic mechanisms by which

these behaviors affect the development of allergic diseases."