People who were young parents in the 1970s and 80s will remember the fear inspired by babies dying for seemingly no reason. It is not unusual for parents of this generation to recount creeping into their baby's room just to make sure he or she was still breathing. Since then, the Back to Sleep movement is credited with saving some lives and some causes have been identified for this crib death, including metabolic disease.
Most FAODs are survivable, but even some relatively mild FAODs can be fatal for infants if the signs are not noticed early and treated appropriately. In fact, the inclusion of tests for FAODs on the newborn screens (the heel-prick test given on the second or third day of life) in most states appears to correlate with a dip in the number of Sudden Infant Deaths (SIDs). This correlation is unclear due to the concurrent efforts to stem SIDs from other causes.
Sudden Infant Death Syndrome is the name that was given in the 1970s to unexplained deaths of infants under one year of age. Though the problem was as old as history itself, the naming of it as SIDs struck anxiety into generations of new parents. Over the last 30 years, many causes have been found for the once unexplained deaths of infants under one year of age. Long thought to have something to do with faulty respiration in infants, SIDs researchers identified risk factors for SIDs. Parents have been warned to avoid putting their babies to bed tummy-down. They have been told to leave the crib empty except for the infant – no toys, pillows, blankets, or crib bumpers. Co-sleeping, soft surfaces, respiratory illnesses and tobacco smoke have all been found to contribute to SIDs.
According to the National Center for Health Statistics, in the late 1990s, as many as 6,000 deaths in the United States were listed as SIDs deaths. As late as 2001, SIDs was still a leading cause of death in infants between 28 days of age and one year. The Back to Sleep campaign had started in the mid-1990s and is generally considered a success though deaths attributed to SIDs still range between 2,000 and 2,500 per year in the United States. As SIDs is a diagnosis of exclusion – meaning it is not itself a cause, but is listed as the cause when no other can be found – those deaths remain unexplained.
No one knows the exact number of deaths due to FAODs in infants that may have been attributed to SIDs over the years. What is known is that FAODs often appear in infants with quiet symptoms, sleepiness, lethargy, and unwillingness to suck. It is considered likely that some of those SIDs deaths were actually due to FAODs or perhaps some other rare mitochondrial disorders. Among scientists, estimates range from 7 percent to 20 percent of SIDs deaths were actually undiagnosed FAODs. One reason for the difficulty in pinpointing FAODs as a cause of death in infants is that many are difficult to diagnosis post-mortem because the tests that would indicate an FAOD rely on catabolism, which is a process of living organisms, not detectable after death.
Less important than pinpointing the exact percentage of SIDs deaths in the past due to undiagnosed FAODs is the simple precaution of monitoring all infants, especially in their first days and weeks of life. As new parenthood is often considered an exhausting time, a sleepy baby has traditionally been viewed as “a good baby.” Parents must be made aware that infants who sleep longer than three or four hours should be checked. Any lethargy, coolness, inability to suck, or other symptom should be cause for alarm. Most families with known histories of metabolic disorders are aware of this, but when an FAOD first appears in a family, it is common that the family has no frame of reference and may fear being seen by their doctors as alarmists if they complain that their baby is too sleepy. Busy doctors may also grow used to irrationally cautious parents and dismiss legitimate concerns. Both families and doctors need to consider that while each individual FAOD is rare, taken together they form a significant population.
Fortunately, the NBS has reduced the guesswork doctors must do. The NBS varies from state to state but at present, 38 states include at least one test for an FOAD in their NBS. The NBS has made identification of infants with FAODs much quicker, often before they leave the hospital. It must be kept in mind that not all FAODs are included in the tests but the more common ones are the likeliest to be included. That still leaves 12 states that do not test for any FAOD and some of the rarer FAODs are not tested for in any state. Also, most NBS are what is known as dried blood spot tests and a few FAODs require plasma for an accurate test. If any of the common symptoms of FAODs are noticed in a newborn or older infant, especially if an older sibling died in infancy of unexplained causes, FAODs should be considered and tests run.
In families where there is a known history of FAODs or SIDs, parents and doctors may want their newborns treated as if the diagnosis were made, with placement in the Neonatal Intensive Care Unit (NICU) immediately after birth, regardless of any lack of symptoms, until such time as tests rule out an FAOD.
Parents may want to familiarize themselves with the disorders included in their state NBS. For more information on specific states and what tests are done, visit http://www.babysfirsttest.org/newborn-screening/states.