Risk Factors For Mental Retardation Research Articles

Pre-natal and Post-natal Risk Factors for Mental Retardation among Children in Varanasi

The present study was aimed to investigate the pre-natal and post-natal risk factors for mental retardation among children in Varanasi. The sample of the study was categorized into three categories viz. mild, moderate and severe. The sample size consisted of 150 mentally retarded children: 34 mild, 96 moderate and 20 severe in the age group of 5-20 years. Purposive sampling technique was done with the help of interview schedule. Results of the study indicated that the maternal age at conception, excessive use of nicotine and alcohol during the pre-natal period, child prematurity and nutritional disorder in the natal and post-natal period were the prime causes behind mental retardation.

Seizures and intellectual outcome: Clinico-radiological study of 30 Egyptian cases of tuberous sclerosis complex

Background and objectives Tuberous sclerosis complex (TSC) is a multi-systemic disorder that involves primarily CNS, skin, kidney and heart. The aim of this study is to determine whether seizures type, interictal EEGs and tubers burden in MRI are correlated to seizure and intellectual outcome, and to identify the clinical risk factors for mental retardation and developing autism in these patients. Methods This was a prospective study that was conducted on 30 Egyptian children with tuberous sclerosis complex (TSC), diagnosed according to the criteria of National Institutes of Health consensus conference revised the diagnostic criteria for TSC. All patients underwent clinical and psychometric evaluation, interictal EEG, and MRI brain. Results and conclusions We found that poor intellectual outcome is related to early onset of seizures, infantile spasms, severely epileptogenic EEG findings and tuber burden on the Left side. Autistic behavior is related to seizure type (more with infantile spasms), severely epileptogenic EEG findings, frontal location of tubers and higher number of tubers (>8).

Infantile spasms and intellectual outcomes in children with tuberous sclerosis complex

To assess intellectual outcomes in a clinic-based population of patients with tuberous sclerosis complex (TSC) who also have a history of infantile spasms (IS) and to identify clinical risk factors for mental retardation in these patients. This is a retrospective study of 50 patients with TSC and IS seen consecutively at the Massachusetts General Hospital Tuberous Sclerosis Comprehensive Clinic from December 2001 to October 2003. Data were obtained by chart review and by interview with patients' parents. Thirty-two (64%) of 50 patients with TSC with IS were found to have mental retardation (IQ or developmental quotient < 70). Three clinical variables showed an association with mental retardation: increased duration of IS from clinical onset to cessation (odds ratio [OR] per 1-month interval 1.09, 95% CI: 1.03 to 1.15, p = 0.004), increased time from treatment initiation until IS cessation (OR 1.07, 95% CI: 1.01 to 1.14, p = 0.020), and poor control of other seizures after IS (OR 17.76, 95% CI: 3.47 to 129.1, p = 0.00004). The following variables did not show an association with intellectual outcome: gender, initial seizure type, age at IS onset, or time from IS onset to treatment initiation. In patients with tuberous sclerosis complex who also have a history of infantile spasms (IS), the rate of mental retardation may be lower than previously reported. The risk of mental retardation increases significantly with prolonged duration of IS, prolonged time from treatment initiation until the cessation of IS, and poor control of subsequent seizures after IS.

Early Risk Factors for Mental Retardation: Role of Maternal Age and Maternal Education

The predictive value of maternal age and education in relation to rates of administratively defined mental retardation in a 3-year birth cohort (N = 267,277) was studied. Low maternal education placed individuals at increased risk for both educable mentally handicapped (EMH) and trainable mentally handicapped (TMH) placements. Older maternal age was associated with increased risk of mental retardation, but for individuals with EMH, this age effect was only seen in the lowest education group. In terms of population-level risk, it was younger mothers with 12 years of education or less whose births were associated with the greatest proportion of mental retardation. From a public policy viewpoint, children born to mothers with low levels of education are an important group to target for prevention/early intervention efforts.

Prenatal and postnatal risk factors for mental retardation among children in Bangladesh.

This study evaluated the contribution of prenatal, perinatal, neonatal, and postnatal factors to the prevalence of cognitive disabilities among children aged 2-9 years in Bangladesh. A two-phase survey was implemented in 1987-1988 in which 10,299 children were screened for disability. In multivariate analyses, significant independent predictors of serious mental retardation in rural and urban areas included maternal goiter (rural odds ratio (OR) = 5.14, 95% confidence interval (CI): 1.23, 21.57; urban OR = 4.82, 95% CI: 2.73, 8.50) and postnatal brain infections (rural OR = 29.24, 95% CI: 7.17, 119.18; urban OR = 13.65, 95% CI: 4.69, 39.76). In rural areas, consanguinity (OR = 15.13, 95% CI: 3.08, 74.30) and landless agriculture (OR = 6.02, 95% CI: 1.16, 31.19) were also independently associated with the prevalence of serious mental retardation. In both rural and urban areas, independent risk factors for mild cognitive disabilities included maternal illiteracy (OR = 2.48, 95% CI: 0.86, 7.12), landlessness (OR = 4.27, 95% CI: 1.77, 10.29), maternal history of pregnancy loss (OR = 2.61, 95% CI: 0.95, 7.12), and small for gestational age at birth (OR = 3.86, 95% CI: 1.56, 9.55). Interventions likely to have the greatest impact on preventing cognitive disabilities among children in Bangladesh include expansion of existing iodine supplementation, maternal literacy, and poverty alleviation programs as well as prevention of intracranial infections and their consequences. Further population-based studies are needed to confirm and understand the association between consanguinity and serious cognitive disability.

The environment and mental retardation

A wide range of environmental factors affect intelligence and mental retardation. Biological risk factors for mental retardation include malnutrition; exposure to toxins such as lead, alcohol, and PCBs, and being born at LBW. Social influences from homes, schools, and cultures are related to intelligence and mental retardation although the direction of effect is difficult to determine. Randomized early intervention studies with children in poverty provide the best data showing that increased intelligence and adaptive behavior is possible, although significant and sustained effects only result from intensive services of long-term duration.

Maternal and neonatal risk factors for mental retardation: defining the ‘at-risk’ child

Objective: To determine how mental retardation at age seven is related to certain maternal, perinatal, and neonatal characteristics. Method: A sample of 35 704 children followed from the prenatal period to age 7 years in the Collaborative Perinatal Project provided data on nine maternal and pregnancy characteristics and 12 neonatal factors. Results: Low socioeconomic status of the family (SES) accounted for 44–50% of mental retardation and a low level of maternal education accounted for 20%. Other prenatal factors with significantly elevated relative risks, ( P < 0.05) were maternal IQ score less than 70, weight gain in pregnancy less than 10 pounds and multiple birth. Maternal anemia in pregnancy accounted for 14% of mental retardation in blacks, and, urinary tract infections accounted for 6% of mental retardation in whites. Significant elevations in relative risk were found for major genetic and post-infection syndromes, CNS malformations, cerebral palsy, seizures, abnormal movements or tone, and low birth weight. Relative risk was also significantly increased with low 1 minute APGAR, primary apnea, and head circumference and length more than 2 SD below average but only in the low SES black subgroup. Conclusion: Early developmental events can be ranked on the basis of the strength of their association with mental retardation and such rankings can be used as a guide for defining risk status in early infancy.

Variation in the influence of selected sociodemographic risk factors for mental retardation.

This study explored the utility of subdividing mental retardation into groups based on the presence of other neurological conditions. Data were abstracted from birth certificates as part of a case-control study of mental retardation among 10-year-old children. The study sample included 458 case children and 563 control children selected from public schools. Case children were subdivided on the basis of intelligence quotient (IQ) score and the presence of other neurological conditions. Other neurological conditions were more common with severe mental retardation than with mild mental retardation. Regardless of IQ level or the presence of other neurological conditions, boys were more likely than girls to have mental retardation. Older mothers were more likely than younger mothers to have a child with mental retardation accompanied by another neurological condition. High birth order, Black race, and low maternal education were associated with a higher prevalence of isolated mental retardation. These findings suggest that sociodemographic risk factors for mental retardation vary according to the presence of other neurological conditions and that subdivisions based on medical or physical criteria may be useful in epidemiologic studies of mental retardation.

Mental retardation associated with parental smoking and alcohol consumption before, during, and after pregnancy

Methods. In an epidemiologic study, parental alcohol consumption and smoking before, during, and after pregnancy were studied as possible risk factors for mental retardation in offspring. The parents of 306 mentally retarded children (cases) and 322 physically handicapped children (referents) were interviewed about their lifestyle habits from 3 months preconception to 6 months postnatal. Results. Odds ratios with 95% confidence intervals were calculated as risk indicators. For fathers who smoked a pipe or cigars, an odds ratio of 2.4 (95% CI: 1.2–5.1) was observed. Maternal alcohol consumption was increased among the case mothers with risk ratios ranging from 1.7 (95% CI: 1.2–2.3) preconception to 1.4 (95% CI: 1.0–2.0) during the fetal period. These risks were more pronounced for the mothers who consumed ⩾3 drinks/day once or twice a week. Conclusions. This study suggests that paternal smoking and maternal alcohol consumption are risk factors for mental retardation in offspring.

Risk factors for mental retardation.

Risk factors for mental retardation were studied prospectively in 12 000 children born in northern Finland in 1966 and followed to the age of 14 years. The number of untraced children was less than 2 per 1000. Altogether 326 children had an IQ less than 86, and the incidence of severe retardation (IQ less than 50) was especially high. An incidence figure for children with mental retardation, a separate figure for healthy children, and also the death rate were calculated for each disease. Only in the cases of Down's syndrome and some hereditary diseases were all the exposed children mentally retarded; in other diseases some children did not seem to suffer any sequelae. A risk factor could be found for 50.6% of the total number of children with mental retardation, the percentage decreasing from the severest to the mildest form (86.7%, 45.4%, and 30.9%). Some 9.4% of the healthy children and 77.7% of those who died had had one or more of these conditions. Prenatal conditions were most often associated with severe mental retardation (64%), and perinatal conditions with mild retardation, (IQ 50 to 70; 27%) and mental subnormality (IQ 71 to 85; 18%). Cases with no known risk factor were more common among boys than girls.