Intended for healthcare professionals

Rapid response to:


Increase in autism is due to changes in diagnosis, study claims

BMJ 2004; 328 doi: (Published 12 February 2004) Cite this as: BMJ 2004;328:364

Rapid Response:

Just pondering

Vittal Katikireddi comments (1) that the researcher in a recent study
“set out to identify whether the number of diagnoses of autism had
progressively increased over the last decade and, if it had, what
environmental exposures were related to the increase.”
And later

"Similarly, there was no difference in the medicines or illnesses
present in the mothers of autistic boys during pregnancy compared to
mothers of normal boys”

I wondered if the conclusions of the study might differ if their
design had included taking a history of pre-existing Auto-Immune
conditions present in the wider family or identifying those that may have
been present but were subsequently diagnosed in the mother or father some
time after the childs birth (3) or considered pre-natal exposure to such
toxins as lead (4) as one of the environmental factors.


(1)Increase in autism is due to changes in diagnosis, study claims
Vittal Katikireddi BMJ 2004;328:364 (14 February),

(2)Pharmacotherapy. 2003 Dec;23(12):1524-30
Epidemiology and possible causes of autism.
Jick H, Kaye JA.

(3)Katona S J

(4) Opler, M. G. A. et al
Prenatal lead exposure, -aminolevulinic acid, and schizophrenia
Full text pdf:

Competing interests:
Parent of Autistic Child

Competing interests: No competing interests

18 February 2004
MC Feliciello