INTRODUCTION

Autism is a severe life-long developmental disorder that compromises functioning across multiple domains including social behavior, language, sensory function, and ritualistic/repetitive behaviors and interests¹.

The etiology of these disorders is complex, and in most cases the underlying pathological mechanisms are unknown. Nevertheless, there is an overwhelming evidence for organic origins. The organicity manifests itself in diverse ways, including genetic factors, peri-natal insults as well as neuro-chemical and immunological factors².

The etiology of autism is unknown, although prenatal exposures have been the focus of epidemiological research for over 40 years. Advanced parental age at birth was one of the factors associated with autism risk³.  

As autism-spectrum conditions are being increasingly recognized, studies suggest that appropriate services should plan to meet the needs of between 1-2% of primary school-aged population⁴. 

The aim of this study was to investigate the socio-demographic characteristics and some of the risk factors associated with the occurrence of autism in a sample of Egyptian autistic children.

SUBJECTS AND METHODS

Site of the study:

·          Children to be enrolled in the study were selected from those attending the Jesuits and Brothers Association for Development day care project (JBAD), in Minia.

·          This foundation is located in the center of Minia city; they offer their services to a large catchment area including both urban and rural Minia districts. Mentally ill children are the object of the center's attention.

·          Fifty sex children are enrolled in the institute, 14 of those are supposed to be autistic, 20 with cerebral palsy and another 22 with various degrees of mongolism.

Subjects of the study:

-        Group (1): The autistic children: These are 14 children, supposed to have autism. They are already enlisted in the center's activities, 12 of them are males and 2 are females.

-        Group (2): The siblings of those autistic children (number=28).

Tools of the study:

               The following tools and techniques were applied to both groups of the study to fulfill the aim of the work:

A.           Sociodemographic data sheet (to both groups):

It consists of information about the name, age, sex, the patient mother's age at birth of child, order and season of birth. This scale includes mother's and father's education and occupation, the number of bedrooms in the house and the average number of house hold members in each room in addition to monthly family income. According to this scale children were classified into: high, low and very low social classes⁵.

B.     Detailed Clinical psychiatric interview (To group 1 only).

C.     Sheet of pregnancy and birth complications (to both groups):

This sheet was designed to include questions covering the possible peri-natal risk factors which were reported to be related to autism in some research studies^6,7. It covers aspects of three areas; prenatal, natal and postnatal periods. Each one covers the complications occurring during pregnancy, labor and early postnatal period respectively.                                     

D.     Childhood Autism Rating Scale (CARS) (to both groups):

This 15-item behavior rating scale is the product of long term empirical research. It helps to identify children with autism and to distinguish them from developmentally handicapped children who are not autistic, and to distinguish mild-to-moderate from severe autism⁸.

CARS includes items, each covers a particular characteristic, ability, or behavior using a 7-point scale. After the child has been rated on each of the 15 items, a total score is computed by summing the individual ratings. Children who score above a given point are categorized as autistic⁹.

Statistical Analysis:

The collected data were organized, tabulated and analyzed using the SPSS version 12 for the statistical analysis. For quantitative variables, the mean and standard deviation were calculated. Categorical variables were demonstrated in number and percent and compared by using Cui-square. Significance was considered when p value was equal to or less than 0.05.

RESULTS

The age of the autistic patients in our study ranged between 4-18 years. The means and standard deviation (SD) of age was 10.9±4.1. The patient group contained 12 males (85.7%) and 2 females (14.3%) (Table 1). Mothers were found to be generally older in age at time of delivery of their autistic children than at delivering their non-autistic siblings (Table 2), the difference was statistically significant. Within the patients group, 9 patients (64.3%) were born in winter, 5 patients (35.7%) were born in summer. While in control group 13 subjects (46.4%) were born in winter, 8 subjects (28.6%) were born in summer (Figure 1), the difference between the 2 groups was statistically insignificant (p. = 0.2).

Regarding the peri-natal complications in the autistic children, the natal complications showed the highest percentage (64.3 %), followed by prenatal complications (50 %) then postnatal complications (21.4%) (Table 3). As for prenatal complications, the difference between both groups was statistically significant regarding only gestational hypertension and gestational vaccination (Table 4).

Labor complications were found in 21.4% of the patients group in comparison to 7.1% of the control group (Table 5). Delayed crying was reported in 64.3% of the patients group in comparison to only 7.1% of the control group and the difference between the 2 groups was highly statistically significant regarding that complication (p<0.0001). On the other hand, the difference between the 2 groups regarding post-natal complications was statistically insignificant (Table 6).

It was not surprising to find that the autistic patients scored much higher than the control subjects on the CARS and the difference was highly statistically significant (P= 0.0001) (Table 7).

Table 1. General description of socio-demographic data in the patients group.

Table 2. Mother's age at birth in patients and control groups.

* Significant at p ≤0.05

Figure 1. Season of birth in both patients and control groups.

Table 3. Comparison between patients and control subjects regarding the sum of prenatal, natal, and postnatal complications.

* Significant at p <0.0001

Table 4. Comparison between patients and control subjects regarding the details of prenatal complications.

DM = Diabetes Mellitus            Ges. HTN = Gestational Hypertension

* Significant at p <0.009         * Significant at p <0.002 

Table 5. Comparison between patients and control subjects regarding the details of natal complications.

* Significant at p <0.0001

N.B: Labor complications include prolonged labor done at home, by other medical personnel, Preterm or post term, aided delivery (forceps or ventose) or C.S.

Table 6. Comparison between patients and control subjects regarding the details of postnatal complications.

Table 7. Comparison between patients and control subjects regarding the global ratings of CARS.

* Significant at p <0.0001

CARS Childhood Autism Rating Scale

DISCUSSION

The mean age of the patient group in our sample was 10±4.1 years. Other studies may include older ages or even adults with autism^10,11. The difference between mean ages of patient groups in the current study and other studies can be attributed to the nature of the services provided by (JBAD) institute whose facility tends to serve children and young patients. The increased awareness of the disorder and the relatively higher prevalence of adults with autistic spectrum disorders (ASDs) in the western countries may explain the older age in many of the studies in literature¹². Meanwhile, the recognition of autism in the upper Egyptian population is still in its cradle.

Although the sex ratio reported in several studies is 3-4 male, 1 female⁷, this was not the case in this study as it showed male to female prevalence of 7:1. The limited number of patients group in this study (14 patients) may be the reason of this difference.

The mean age of the patients' mothers at their birth in this study was 31.6±5.2 years while in the control group was 29.0±3.3 and this difference was statistically significant. This result came coinciding with the results of Hultman et al.¹³, who reported a statistically significant difference between the mean maternal age in the autistic sample (30.7 years) and in the general population (26 years) and argued about a strong tendency towards increasing risk of autism in the child with increasing maternal age. Meanwhile it was contradictory to the findings of El-Bakry et al.¹⁴ and Omar et al.¹⁵, who found that there was no difference between the patient and the control groups in the mother's age at birth in their sample.

In the current study it was found that the highest birth rates among individuals with autism were in winter (36.7%) and summer (31%) respectively and this result is consistent with the study of Torrey et al.¹⁶. However, this is not in agreement with a more recent large study which detected no association between month of birth and prevalence of autistic spectrum disorders¹⁷.

The incidence of prenatal, natal and postnatal complications in this study was higher in the patient than in the control groups. These results support the previous findings^6,7,18 suggesting a consistent association of unfavorable events in pregnancy, delivery, and the neonatal phase and autism. Any of these complications can affect the brain development of the fetus and consequently the cognitive functions. Thus it could be suggested that good prenatal and natal care can protect the fetus against these effects¹⁹.

In this study, the incidence of gestational hypertension was significantly higher in mothers of patients during pregnancy than in the control group and this is similar to other studies as Juul-Dam et al.⁷, who reported higher incidence of gestational hypertension in mothers of their sample.

The issue of whether mother vaccinations during pregnancy cause or contribute to autism is one of the most controversial and contentious in this field. Nonetheless, the present study reported that tetanus vaccination during pregnancy has a statistically significant positive correlation to the development of ASDs when compared to the control group. This result agrees with those of Yazbak¹⁹, who hypothesized that maternal immunization before or during pregnancy predisposes the child to autism.

On the other hand, labor complications such as prolonged labor and Caesarian section occurred at a higher rate in several studies^20,21. The results of the current study were also consistent with these studies, although the difference between the two groups in our study was not statistically significant. Natal complications may be associated with increased risk of fetal compromise, which may have lasting neurological consequences that can influence brain development and function later on²².

In addition, delayed crying in the current study was significantly higher in the patient group than in the control group. This is consistent with the results of other studies^6,7. This may be associated with impairment in the delivery of suitable oxygen required to all organs of the child, including the brain during the critical moments of delivery.

Regarding the postnatal complications, this study found no significant difference between the patients and the control groups. This was in agreement with some other studies^20,21. In contrast, other earlier studies^23,24 found that postnatal complications, especially postnatal fever was significantly higher in the patients than in the control groups of their studies.

Conclusion

More attention to the study and care of autistic children is needed. Early rather than late pregnancy should be encouraged. Proper ante-natal care and mothers' education as well as good care of mother and her baby at and after delivery may all be important tools to reduce the occurrence of autism in the future.

[Disclosure: Authors report no conflict of interest]

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