Causes of death in remote symptomatic epilepsy

OBJECTIVE

To determine the causes of death of individuals with developmental disabilities that occur more frequently among those with remote symptomatic epilepsy (i.e., epilepsy occurring in persons with developmental delay or identified brain lesions) than for those without.

METHODS

The authors compared causes of mortality in persons with (n = 10,030) and without (n = 96,163) history of epilepsy in a California population of persons with mild developmental disabilities, 1988 to 2002. Subjects had traumatic brain injury, cerebral palsy, Down syndrome, autism, or a developmental disability with other or unknown etiology. There were 721,759 person-years of data, with 2,397 deaths. Underlying causes of death were determined from the State of California's official mortality records. Cause-specific death rates and standardized mortality ratios (SMRs) were computed for those with and without epilepsy relative to subjects in the California general population. Comparisons were then made between SMRs of those with and without epilepsy, and CIs on the ratios of SMRs were determined.

RESULTS

Death rates for persons with epilepsy were elevated for several causes. The greatest excess was due to seizures (International Classification of Diseases-9 [ICD-9] 345; SMR 53.1, 95% CI 28.0 to 101.0) and convulsions (ICD-9 780.3; SMR 25.2, 95% CI 11.7 to 54.2). Other causes occurring more frequently in those with epilepsy included brain cancer (SMR 5.2, 95% CI 2.2 to 12.1), respiratory diseases (SMR 1.7, 95% CI 1.2 to 2.5), circulatory diseases (SMR 1.3, 95% CI 1.0 to 1.7), and accidents (SMR 2.7, 95% CI 1.9 to 3.7), especially accidental drowning (SMR 12.8, 95% CI 7.0 to 23.2).

CONCLUSIONS

Remote symptomatic epilepsy is associated with an increased risk of death. Seizures, aspiration pneumonia, and accidental drowning are among the leading contributors.

Fetal stroke

Fetal stroke, or that which occurs between 14 weeks of gestation and the onset of labor resulting in delivery, has been associated with postnatal epilepsy, mental retardation, and cerebral palsy. The entity is caused by antenatal ischemic, thrombotic, or hemorrhagic injury. We present seven new cases of fetal stroke diagnosed in utero and review the 47 cases reported in the literature. Although risk factors could not be assigned to 50% of the fetuses with stroke, the most common maternal conditions associated with fetal stroke were alloimmune thrombocytopenia and trauma. Magnetic resonance imaging was optimal for identifying fetal stroke, and prenatal imaging revealed hemorrhagic lesions in over 90% of studies; porencephalies were identified in just 13%. Seventy-eight percent of cases with reported outcome resulted in either death or adverse neurodevelopmental outcome at ages 3 months to 6 years. Fetal stroke appears to have different risk factors, clinical characteristics, and outcomes than other perinatal or childhood stroke syndromes. A better understanding of those risk factors predisposing a fetus to cerebral infarction may provide a basis for future therapeutic intervention trials. Ozduman K, Pober BR, Barnes P, Copel JA, Ogle EA, Duncan CC, Ment LR. Fetal stroke.

Excess mortality in remote symptomatic epilepsy

BACKGROUND

Published estimates of excess mortality associated with epilepsy vary greatly. How much, if any, of the excess is attributable to the seizures themselves as opposed to an underlying condition causing the epilepsy is not clear from the literature. This article offers evidence that epilepsy per se is associated with excess mortality. The excess varies according to severity and frequency of seizures.

MATERIALS AND METHODS

The authors studied mortality rates of developmentally disabled persons in California with and without epilepsy. In order to focus on the effect on mortality risk of epilepsy per se, they included only persons with good motor function (able to walk and climb stairs) and at worst moderate mental retardation (MR). The data were 506,204 person-years and 1523 deaths among 80,682 California subjects of age 5 to 65 years during the 1988-1999 study period. Mortality rates for persons with epilepsy were compared to rates for persons with no history of epilepsy.

RESULTS

Mortality rates were higher for persons with epilepsy than for those without. Excess death rates (EDRs) varied according to type and frequency of seizures. Combined EDRs were 6 (deaths per 1000 person-years) for persons with recent (< 12 months) history of status epilepticus, 5 for recent history of generalized tonic-clonic (GTC) seizures, 3 for recent history of seizures but no recent GTC seizures, and less than 1 for a history of seizures but no recent events.

CONCLUSIONS

The data presented here are evidence that epilepsy per se is associated with increased mortality. The EDRs reported here may be better measures of excess mortality due to epilepsy than previously published estimates.

Increased mortality in children and adolescents with developmental disabilities

A population-based cohort of 10-year-old children with mental retardation, cerebral palsy, epilepsy, hearing impairment or vision impairment, who were ascertained at 10 years of age in a previous study conducted in metro Atlanta during 1985-87, was followed up for mortality and cause of death information. We used the National Death Index to identify all deaths among cohort members during the follow-up period (1985-95). We estimated expected numbers of deaths on the basis of actual age-, race- and sex-specific death rates for the entire Georgia population for 1989-91. The objective was to quantify the magnitude of increased mortality and evaluate the contribution of specific disabilities to mortality among children and adolescents with one or more of five developmental disabilities. A total of 30 deaths were observed; 10.1 deaths were expected, yielding an observed-to-expected mortality ratio of almost three to one. The numbers of observed deaths exceeded those of expected deaths, regardless of the number of disabilities present, but the ratios were statistically significant (at the 95% confidence level) only in children with three or more co-existing disabilities. In general, the magnitude of the mortality ratios was directly related to various measures of the severity of the person's disability. An exception to this pattern was the elevated mortality from cardiovascular disease among cohort members with isolated mental retardation (three observed deaths vs. 0.2 expected). The specific underlying causes of death among other deceased cohort members included some that were the putative cause of the developmental disability (e.g. a genetic syndrome) and others that could be considered intercurrent diseases or secondary health conditions (e.g. asthma). Prevention efforts to decrease mortality in adolescents and young adults with developmental disabilities may need to address serious conditions that are secondary to the underlying disability (i.e. infections, asthma, seizures) rather than towards injuries, accidents and poisonings, the primary causes of death for persons in this age group in the general population.

Serial assessment of mortality in the neonatal intensive care unit by algorithm and intuition: certainty, uncertainty, and informed consent

OBJECTIVES

Does predictive power for outcomes of neonatal intensive care unit (NICU) patients get better with time? Or does it get worse? We determined the predictive power of Score for Neonatal Acute Physiology (SNAP) scores and clinical intuitions as a function of day of life (DOL) for newborn infants admitted to our NICU.

METHODS

We identified 369 infants admitted to our NICU during 1996-1997 who required mechanical ventilation. We calculated SNAP scores on DOL 1, 3, 4, 5, 7, 10, 14, 21, 28, and weekly thereafter until either death or extubation. We also asked nurses, residents, fellows, and attendings on each day of mechanical ventilation: "Do you think this child is going to live to go home to their family, or die before hospital discharge?"

RESULTS

Two thousand twenty-eight SNAP scores were calculated for 285 infants. On DOL 1, SNAP for nonsurvivors (24 +/- 8.7 [standard deviation]) was significantly higher than SNAP for survivors (13 +/- 6.1). However, this difference diminished steadily and by DOL 10 was no longer statistically significant (12.7 +/- 4.9 vs 10.0 +/- 4.8). On each NICU day, at all ranges of SNAP scores, there were at least as many infants who would ultimately survive as would die. Consequently, the positive predictive value of any SNAP value for subsequent mortality was <0.5 on all NICU days. Prediction profiles were obtained for 230 ventilated infants reflecting over 11 000 intuitions obtained on 2867 patient days. One hundred fifty-seven (81%) of 192 survivor profiles displayed consistent accurate prediction profiles-at least 90% of their NICU ventilation days were characterized by 100% prediction of survival. Twenty-five (13%) of 192 surviving infants survived somewhat unexpectedly; that is, after at least 1 day characterized by at least 1 estimate of "death." Thirty-three (60%) of the 55 nonsurvivors died before DOL 10. Eighty-two percent of the prediction profiles for these early dying infants were homogeneous, dismal, and accurate. Twenty-two (40%) of the 55 nonsurvivors died after DOL 10. Seventeen (78%) of these 22 late-dying infants were predicted to live by many observers on many hospital days. Sixty-one (30%) of 230 profiled patients had at least 1 NICU day characterized by at least 1 prediction of death; 26/61 (43%) of these patients were incorrectly predicted; that is, they survived. Seventeen infants who were predicted to die during but survived nonetheless were assessed neurologically at 1 year. Fourteen (82%) of these 17 were not neurologically normal-8 were clearly abnormal, 1 suspicious, and 5 had died.

CONCLUSIONS

If absolute certainty about mortality is the only criterion that can justify a decision to withhold or withdraw life-sustaining treatment in the NICU, these data would make such decisions difficult on the first day of life, and increasingly problematic thereafter. However, if we acknowledge that medicine is inevitably an inexact science and that clinical predictions can never be perfect, we can ask the more interesting question of whether good but less-than-perfect predictions of imprecise but ethically relevant clinical outcomes can still be useful. We think that they can-and that they must.

Long-term outcomes of childhood meningitis

Meningitis and meningococcal disease remain a major source of anxiety to paediatricians and parents alike. Survival rates have improved with rapid diagnosis and appropriate management. However, survivors remain at risk of long-term neurodevelopmental sequelae.

Developmental outcomes of newborn encephalopathy in the term infant

Newborn encephalopathy is a clinically defined condition of abnormal neurological behaviours in the newborn period. Though most cases have their origin in the preconceptional and antepartum period, newborn encephalopathy represents a crucial link between intrapartum events and permanent neurological problems in the child. The birth prevalence of newborn encephalopathy ranges from 1.8 to 7.7 per 1000 term live births according to the definition used and the population to which it is applied. Few studies have investigated the outcomes of newborn encephalopathy other than for cases solely attributed to intrapartum hypoxia. These adverse outcomes range from death to cerebral palsy, intellectual disability, and less severe neurological disabilities such as learning and behavioural problems. Outcomes following newborn encephalopathy may vary from country to country with 9.1% of affected babies dying in the newborn period in Western Australia and 10.1% manifesting cerebral palsy by the age of two. These compare to a case fatality of 30.5% in Kathmandu and a cerebral palsy rate of 14.5% by one year of age. The study by Robertson et al which followed children with hypoxic ischaemic encephalopathy found an incidence of impairment of 16% among survivors assessed at 8 years with 42% requiring school resource room help or special classes. This review emphasises the great need for comprehensive clinical and educational assessment as these infants approach school entry to enable appropriate educational provisions to be made.

Outcome in prenatally diagnosed fetal agenesis of the corpus callosum

This study of the outcome and prognostic factors in prenatally diagnosed agenesis of the corpus callosum (ACC) was undertaken to see if there are any differences between subgroups, what relationship they have to neurodevelopmental outcome and whether this information aids the counselling of parents of fetuses with the condition. The outcome of 14 prenatally diagnosed fetuses with ACC and 61 postnatally diagnosed patients was assessed in terms of clinical problems, developmental milestones and neurological signs; each patient was then given a score out of 10, 0 being a normal outcome and 10 being the worst outcome, i.e. death or termination of pregnancy. Comparing patients diagnosed pre- and postnatally, several similarities were found indicating that the postnatal group can provide useful information about the prenatal group. There was a higher incidence of ACC in males than females. In the prenatally diagnosed patients complete ACC was more common than partial ACC, although this might be because partial ACC was easily missed. Complete ACC has a worse prognosis than partial ACC (p = 0.001), and when associated with other anomalies, especially of the central nervous system, the outcome is very bad (p < 0.01). The only neurodevelopmentally normal patients were in the isolated partial ACC group. This study highlights the need to perform a detailed review of fetal anatomy and the desirability of determining the karyotype of the fetus in all newly diagnosed cases of ACC so that as much information as possible is available before parents are counselled about the likely outcome.

Effect of micronutrient supplementation on linear growth of children

This review summarizes the results of published, randomized clinical trials that have examined the impact of administration of micronutrients, singly or in combination to infants, preschool and school children on linear growth. Supplementation of single micronutrients resulted in small or no benefits on linear growth. A meta-analysis of zinc supplementation trials confirmed that zinc has a significant but small impact (0.22 sd units) on length gain in children 0-13 years of age. However, a recent study reported a substantially greater benefit (>1 sd) in stunted and non-stunted breast-fed infants 6-12 months of age. With iron supplementation, a beneficial effect was found only in anemic children. Vitamin A supplementation trials have reported little or no benefit on linear growth. Data currently available suggest some impact in children with clinical or biochemical vitamin A deficiency, but this issue needs confirmation. Few studies could be identified where a combination of micronutrients was given as a supplement or as fortified food; in the latter set of studies energy availability was assured. The impact on length without multiple micronutrient supplementation was no greater than that observed with single micronutrients. In conclusion, zinc and iron seem to have a modest effect on linear growth in deficient populations. Vitamin A is unlikely to have an important effect on linear growth. Limited available evidence does not allow us to conclude whether a combination of micronutrients, with or without additional food, would have a greater impact than that seen with zinc alone.

[Outcome of 249 premature infants, less than 29 weeks gestational age]

The aim of this paper was to report the vital and neurological outcome of 249 preterm infants of less than 29 weeks born between 1990 and 1996, and included in a prospective study until two years of age.

RESULTS

The initial mortality rate was 19%. This was related to gestational age and severe transfontanellar ultrasonographically (TFU) detected abnormalities. The rate of follow-up at two years of age was 98%. Neurological sequelae amounted to 12.8%, including four cases of deafness. The possibility of survival without neurological sequelae increased from 52% at 24-25 weeks to 72% at 26-28 weeks of gestational age (p < 0.005). The presence of sequelae was significantly related to severe cranial ultrasonographically-detected abnormalities, to parental social level, and to early neonatal anemia. Normal TFU and/or isolated periventricular hyperechogenicity could not exclude the presence of neurological sequelae which, however, appeared to be less severe than at the onset.

CONCLUSION

Gestational age, severe TFU abnormalities and neonatal anemia play a major role in the rate of mortality and in the neurological sequelae in preterm infants, and can influence the decisions concerning the treatment of this pediatric population.

Aging in individuals with lifelong disabilities

The major research data and findings related to aging among persons with developmental disabilities are discussed. Differences between the aging processes noted in the general population and individuals who have developmental disabilities are highlighted. Topics addressed include prevalence of developmental disabilities and mortality rates for individuals with developmental disabilities. The effects of aging on the senses, the neuromusculoskeletal system, and the cardiopulmonary system are presented along with the clinical implications of these changes in individuals with developmental disabilities who are aging.

Mortality of persons with developmental disabilities after transfer into community care: a 1996 update

More than 2,000 persons with developmental disabilities have recently been transferred from California institutions into community care. Using data on 1,878 clients moved between April 1993 and December 1995, Strauss et al. (1998) found a corresponding increase in mortality rates. In the present report we update that study by analyzing 1996 data. There were 36 deaths, an 88% increase in risk-adjusted mortality over that expected in institutions, p < .01. We again found that persons transferred later were at higher risk than those moving earlier, even after adjustment for differences in risk profiles. In the highest functioning group, the community mortality rate was tripled. Death certificate information was also analyzed.

Outcome of very preterm birth: children reviewed with ease at 2 years differ from those followed up with difficulty

AIM

To determine whether those most easily reviewed in a population prevalence study differ from those followed up only with difficulty.

METHODS

All babies born before 32 weeks of gestation in the North of England in 1983, 1990, and 1991 were traced, and all the survivors assessed at two years by one of two independent clinicians.

RESULTS

818 of the 1138 live born babies survived to discharge. There was some non-significant, excess disability in the 5% of long term survivors who were difficult to trace because of social mobility, but eight times as much severe disability in the 1% (9/796) in care and in the 5% (38/796) whose parents initially failed to keep a series of home or hospital appointments for interview, and five times as much emergent disability in the 2.7% (22/818) who died after discharge but before their second birthday. Had the babies who were seen without difficulty been considered representative of all the babies surviving to discharge, the reported disability rate would have been two thirds what it really was (6.9% instead of 11.0%).

CONCLUSIONS

Population prevalence studies that ignore those who seem reluctant to cooperate risk serious ascertainment bias.

An extended Kaplan-Meier estimator and its applications

We develop an extension of the Kaplan-Meier estimator for the case of multiple live states. The method can be used to construct prognostic charts for tracking individuals initially in a given condition. It is also the key component in constructing a longitudinal version of the multistate life table.

External causes of death among persons with developmental disability: the effect of residential placement

The authors analyzed death rates from external causes (accidents, injuries, homicides, etc.) for persons with developmental disability in California. There were 520 such deaths during the 1981-1995 study period, based on 733,705 person-years of exposure; this represents all persons who received any services from the state. Compared with the general California population, persons with developmental disability were at lower risk of homicide, suicide, and poisonings (standardized mortality ratios, 0.31-0.68), but higher risk of pedestrian accidents, falls, fires, and, especially, drowning (standardized mortality ratio=6.22). A major focus of the study was comparisons between different residential settings. Persons in semi-independent living had significantly higher risk than did those in their family home or group homes, with homicides rates being three times higher and pedestrian accidents rates being doubled, while persons in institutions had much lower risks with respect to most causes. Of the 28 deaths due to drug and medication overdoses, 79 percent occurred in supported living or small-group homes. Avoidable deaths could be reduced by making direct care staff more aware of the risks and better trained in acute care, along with improved monitoring of special incidents.

Adverse outcome after multiple pregnancy

There is increasing interest in the outcomes of multiple pregnancies as their numbers rise, mainly owing to advances in fertility-enhancing techniques. In addition, the numbers of multiple births surviving the perinatal period is increasing with the increasing survival of very tiny babies. In order to investigate these outcomes or to evaluate procedures that may improve them, it is important to consider a number of methodological issues that affect the comparability of data both between and within populations. How a birth and a multiple birth are defined, data sources, whether multiple pregnancies or individual births are being counted and the identification of multiple gestations by zygosity and chorionicity will all affect the reported outcome rates. In light of this, perinatal mortality and neurodevelopmental disabilities are examined as adverse outcomes of multiple pregnancies.

Prognosis for survival and improvement in function in children with severe developmental disabilities

OBJECTIVE

To derive prognostic data for survival and clinical improvement in children with severe developmental disabilities.

STUDY DESIGN

A 13-year follow-up study of several cohorts of children initially evaluated before their first birthday. The outcomes studied were survival and improvement in condition. Methods were used to overcome limitations in previously published work on the same California data base. Of the 11,912 children who received services from the California Department of Developmental Services between January 1980 and December 1993, we focused on three cohorts defined according to mobility and need for tube feeding.

RESULTS

Children who were tube fed and unable to lift their heads by ages 3 to 12 months were at high risk for early death, with a median remaining life expectancy of 3.2 years. Of those who survived an additional 2 years, the condition of about one third improved. A substantial majority of those who either showed improvement or died had done so by that age.

CONCLUSION

By age 5 years, the prognoses for survival and improvement have to a large extent been clarified. For children who survive to age 5 years, even those in the lowest functioning cohort have a 60% chance of surviving an additional 5 years. Detailing the probabilities of various outcomes at various ages should be useful to parents, pediatricians, and others concerned with children with developmental disabilities.

[Neonatal, neurologic and psychosocial findings in higher order multiple births. Follow-up for 3 to 10 years]

We examined the outcome of 9 triplet, 3 quadruplet, 1 quintuplet and 1 sixtuplet pregnancies delivered between 1979-1989 at the perinatal center of the RWTH Aachen. The course of pregnancy and neonatal period were retrospectively analysed. The follow-up program covered at least 3, up to a maximum of 10 years. 12 families could be interviewed concerning psychosocial effects. The neonatal mortality was 4%. Neonatal morbidity; hyaline membrane disease (n = 18), intraventricular hemorrhage (n = 9), pneumothorax (n = 7), patent ductus arteriosus (n = 7), bronchopulmonary dysplasia (n = 8). At the age of 2 years 63% of the children were considered to be normal on developmental assessment, 17% showed mild, 20% severe developmental delay. With 3 to 10 years 83% were normal, 17% severely handicapped. In total 20% of the children died or showed severe handicap. Higher order multiple pregnancies make great demands on the perinatal medicine and lead in spite of an improved prognosis to a remaining burden for the children and their parents.

Tubefeeding and mortality in children with severe disabilities and mental retardation

OBJECTIVE

To study the contribution of tubefeeding to mortality for children with severe disabilities and mental retardation. Previous research has suggested an association between tubefeeding and mortality. However, risk has never been determined using population-based data or defined in regard to patient variables.

METHODS

Retrospective analysis of a comprehensive statewide data set comprised of 4921 children with severe disabilities and mental retardation living in community and congregate care settings. The outcome measure was mortality; primary study variables included the presence of a feeding tube, measures of functional independence, type of residence, and medical comorbidity.

RESULTS

There were four findings. First, the use of a feeding tube was associated with virtually every disability. Second, when no study variables were controlled, statistically significant differences in mortality rates were noted between children who were tubefed and those who were not. The relative risk of mortality associated with use of a feeding tube was 2.1. Third, the use of a feeding tube was associated with a reduction in relative risk of mortality in children with tracheostomy (relative risk of mortality: .55). However, this association did not achieve statistical significance. Fourth, when study variables were controlled in a multivariate analysis, feeding tube use was associated with no identifiable increase in mortality among children with very severe disabilities, but was associated with an approximated doubled mortality rate among those with less severe disabilities.

CONCLUSIONS

We hypothesize that the increased mortality associated with tubefeeding may be attributable to a differential increase in pulmonary disease secondary to overly vigorous nutritional maintenance and subsequent aspiration after tube placement. For children with tracheostomy this risk may be reduced. If tracheostomy proves to be associated with a relatively more favorable outcome for tubefeeding, we hypothesize that it would reflect the benefits of tracheostomy in allowing access to the airway for suctioning and ventilation. Given the observed higher mortality rates among the less severely disabled children who are tubefed and the substantial costs associated with tubefeeding, a prospective, controlled study may be clinically indicated, ethically justifiable, and economically warranted.

Developmental and behavioral issues in childhood injury prevention

Injuries are the most important cause of mortality, morbidity, and disability during childhood and adolescence. Injuries with the greatest impact on the behavioral and emotional development of the child are head injuries and severe burns, both of which can markedly impact on subsequent development. Important risk factors for injury are gender, age, socioeconomic status, developmental status, behavior problems, substance abuse by parent and adolescent, and parents' perceptions of injury risk. These factors interact to increase or decrease the risk of injury in any given child and are much more meaningful than the futile search for the "accident-prone" individual. These factors must be taken into consideration when planning intervention strategies to ensure optimal effectiveness of intervention.