|Abstract||Background: Although autism is a global disorder, relatively little is known about
the prevalence of consanguinity among autism spectrum disorder (ASD) individuals.
Also, the relation of ASD comorbidities (Epilepsy and Intellectual Disability) to
consanguinity have not been explored.
Aims: We aim to estimate the global prevalence of consanguinity among the ASD
individuals and compare it that among different populations. In addition, we aim
document the prevalence of epilepsy and ID in relation to consanguinity in individuals
diagnosed with ASD in Qatar and to assess the association between epilepsy and ID
and consanguinity and other potential socio-demographic factors, environmental and
other clinical factors.
Methods: Meta-Analysis of observational studies reporting prevalence of
consanguinity among ASD individuals from 8 countries were searched systematically
in important databases including EMBASE, PubMed and Academic Search Complete.
Individual studies were screened by two reviewers independently, extracted data and
assessed the risk of bias using a risk of bias tool. Random Effect model was used to
calculate pooled weighted estimates due to considerable heterogeneity. Subgroup
analysis was also calculated.
Moreover, secondary data were analyzed using the cross-sectional study on profiles
and correlates of ASD clinical sample in Qatar. Descriptive, univariable and
multivariable analysis were conducted to estimate the prevalence of consanguinity,
epilepsy and ID among ASD individuals in this cohort and assess association to other
potential confounding determinants.
Results: The meta-analysis included 10 studies reporting prevalence of consanguinity
among ASD cases. The pooled estimate of consanguinity among ASD cases was 24%
(95%CI:17%-32%). Subgroup analysis by the study country led to a higher pooled
estimate of consanguinity of 38% (95%CI:28%-49%) in the GCC countries compared
to other than GCC countries with a pooled estimate of 16% (95%CI:11%-23%).
The cross-sectional included a total of 171 ASD cases. Male to female ratio 4:1 and
mean age was 13.5 years. Epilepsy was reported by 19%. ID reported by 83% of the
cases. 76.6% were nonverbal. Eighty-three percent of the families had one proband,
9.9% had 2 probands, and 7.1% had more than two. The association between epilepsy
and ID among ASD patients and consanguinity was not statistically significant (P
value >0.05) controlling for other potential risk factors.
Conclusion: The globally estimated pooled consanguinity prevalence among ASD
patients was 24%, GCC countries showed a higher pooled prevalence (38%). The
clinical sample used did not provide any evidence on association between both
epilepsy and ID and consanguinity among ASD patients in Qatar. Further larger
studies with much better large and representative sample may be required to confirm