Kindergartners, college students and retirees have attention-deficit hyperactivity disorder

I sometimes joke that I got ADHD in college, like a flu going around the dorm (CDC Diagnostic Criteria, Rosenberg, 1998, Angier, 1991, Kluger, 2005, Gilman, 2005). I became easily distracted, fidgety, sometimes forgetful or inattentive of simple, daily activities and occasionally very restless. Most likely, since the symptoms are few in number and not significantly impairing I was simply noticing the effects of a high-stress, academically-challenging environment navigated on little sleep. Although typically a childhood disease, the symptoms may last until adulthood; for some people with attention-deficit/hyperactive disorder symptoms remain unnoticed until placed in a challenging environment with sudden independence, like college. Furthermore, some people afflicted with ADHD are not diagnosed until even later in life—retirement. The structured, scheduled work life they led for decades was taken away exposing for the first time symptoms they later realized were themes throughout their lives. For many people the impetus to see a doctor about these symptoms was a diagnosis of ADHD in their grandchild followed by their child, as ADHD seems to have a genetic component.

According to the Diagnostic and Statistical Manual for Mental Disorders IV there are three types of ADHD (CDC Diagnostic Criteria, CDC What is ADHD, Angier, 1991, Angier, 1994, Moffitt, 2007). One, the predominantly inattentive type, comprised of symptoms such as carelessness, distraction, forgetfulness, trouble organizing, following instructions or completing tasks that require attention or mental effort for long periods of time and inability to keep track of objects. Two, the predominantly hyperactive type, comprised of symptoms such as trouble waiting one’s turn or keeping still, frequent interrupting and excessive talking, restlessness and difficulty remaining quiet. And three, the combined type if criteria are met for both inattentive and hyperactive types. Interestingly, the discrepancy between American and European diagnostic statistics is likely due to a difference in diagnosis. European children typically need to be type three ADHD, the combined type, before being diagnosed. When the same standards are applied to subjects the rates of diagnosis between the continents equalizes, although there are still pockets of higher or lower diagnosis due to awareness and diligence of parents and treating physicians. Although some tests, such as for eye movement and coordination can be more sensitive, the predominant observational method of diagnosis illustrates the inherent subjectiveness and need for a biological method of diagnosis. Strep throat can be diagnosed definitively by a bacterial culture from a throat swab but ADHD has no such concrete method. The personal and cultural standards of proper behavior and impairing behavior color diagnosis and even acceptance of the condition as a disability. For example, many Asian cultures turn a blind eye to mental disorders such as ADHD and instead provide harsher discipline to the afflicted child. On the other hand, the US has seen a trend of overdiagnosis, particularly in boys, because of the characteristic “boys will be boys” behavior that is so similar to ADHD symptoms.

ADHD affects approximately 3-7% of children in the United States (three-quarters of whom are boys) (CDC Research Agenda, CDC What is ADHD, CDC A Public Health Perspective, CDC Injuries and ADHD, CDC Peer Relationships and ADHD, CDC Other Conditions Associated with ADHD, Hersey, 1996, Angier, 1991, Angier, 1994, Wallis, 2006, Kluger, 2005, Kluger, 2003, Harding, 2003, das Neves, 2006, Eisenberg, 2007). About half of these children have another behavioral or learning disorder that can complicate diagnosis and treatment. The ADHD child may have trouble making friends, be accident prone, and have trouble in school despite adequate intelligence. The ADHD child may also have more difficulty identifying dangerous situations, like crossing the street and may need to have distractions such as music or TV removed in order to do homework. Adults with ADHD may have trouble concentrating while driving, keeping a job or be more susceptible to drug addiction. On top of this, families must decide with their physician whether or not to put the child on medication (2.5 million children and 1.5 million adults are medicated for ADHD), rely on behavioral therapy and counseling alone, or substitute alternative treatments like the Feingold diet (artificial additives are removed and certain minerals, amino acids and other supplements are added) for medication. Oddly, a good night’s sleep may be enough to alleviate ADHD symptoms and help the child stay on medication. Approximately twice as many children with ADHD also have sleeping disorders, compared to children without ADHD. Poor sleep not only exacerbates ADHD symptoms but also presents some of the same symptoms, much as I saw in college, that could be misdiagnosed as ADHD.

It is unlikely that the apparent rise in ADHD diagnosis is due to a new cause of ADHD (or lax parenting) but to better diagnosis and establishment of the condition itself (Eisenberg, 2007, Hersey, 1996, Angier, 1994, Harding, 2003). The major debates surrounding ADHD, is it overdiagnosed and is it overmedicated, are based on one fact: the cause of ADHD is unknown. With no physical explanation for ADHD no absolute diagnostic criteria can be established and no mechanism for treatment can be explained. The current treatment of amphetamines, such as Ritalin, is based on 7 decades of observation of changed behavior but little else. Similarly, the Feingold diet is based on observed behavioral changes and has been shown by some studies to be as effective as Ritalin in some children, although no cellular explanation can be given for either treatment. Both are based on the theory that the brain cells are not signaling properly and the addition of an amphetamine (Ritalin) or removal of preservatives and artificial additives together with specific supplements (Feingold diet) restore the correct brain function or bypass the missing signaling component. Until a definitive cause of ADHD and resulting treatment are found there will continue to be underdiagnosed and overdiagnosed (and overmedicated) children simply because of different standards of behavior and unruliness and limited spread of more sensitive tests.

CDC ADHD Diagnostic Criteria: http://www.cdc.gov/ncbddd/adhd/symptom.htm
CDC ADHD Research Agenda: http://www.cdc.gov/ncbddd/adhd/dadagenda.htm
CDC What is ADHD?: http://www.cdc.gov/ncbddd/adhd/what.htm
CDC ADHD A Public Health Perspective: http://www.cdc.gov/ncbddd/adhd/publichealth.htm
CDC Injuries and ADHD: http://0-www.cdc.gov.mill1.sjlibrary.org/ncbddd/adhd/injury.htm
CDC ADHD Peer Relationships and ADHD: http://www.cdc.gov/ncbddd/adhd/peer.htm
CDC ADHD Other Conditions Associated with ADHD: http://www.cdc.gov/ncbddd/adhd/otherconditions.htm
Hersey, Jane. Diets and Drugs for Disruptive Children. The New York Times. 1996.
Rosenberg, Merri. Strategies to Manage a Disorder. The New York Times. 1998.
Angier, Natalie. Kids Who Can’t Sit Still. The New York Times. 1991.
Angier, Natalie. The Nation; The Debilitating Malady Called Boyhood. The New York Times. 1994.
Wallis, Claudia. Getting Hyper about Ritalin. Time Magazine. 2006.
Kluger, Jeffrey. Medicating Young Minds. Time Magazine. 2003.
Kluger, Jeffrey. Sleep Deprivation and ADHD. Time Magazine. 2005.
Gilman, Lois. All Jumbled Up. Time Magazine. 2005.
Moffitt, Terrie E. and Maria Melchior. Why does the worldwide prevalence of childhood attention deficit hyperactivity disorder matter? American Journal of                   Psychiatry, Vol. 164, No. 6. 2007.
Harding, Karen L. et al. Outcome-based comparison of Ritalin versus food-supplement treated children with ADHD. Alternative Medicine Review. Vol. 8,             No.       3. 2003.
das Neves, Sergio and Rubens Reimao. Sleep disturbances in 50 children with attention-deficit hyperactivity disorder. Arquivos de Neuro-Psiquiatria. Vol. 65,               No. 2-A. 228-233. 2007.
Eisenberg, Leon. Commentary with a historical perspective by a child psychiatrist: When “ADHD” was the “brain-damaged child.” Journal of Child and                          Adolescent Psychopharmacology. Vol. 17, No. 3. 2007.

Beer, wine make Pasteur leading germ theory champion

Many Americans may know the name Louis Pasteur because of the notice of pasteurization on their milk, but few may know that pasteurization was first applied to wine and beer. Fewer still may realize the impact Pasteur had on germ theory, the idea that every disease is caused by a specific microorganism, which is the central tenet of today’s medicine (1-5).

Louis Pasteur was born in France in 1822. By the age of 32 Pasteur had earned a doctorate in chemistry and a faculty position at the University of Lille. The faculty were asked to use their expertise to solve practical problems and when the father of one of Pasteur’s students, a local distiller, asked for help Pasteur jumped at the opportunity. At the time it was understood that sugar fermentation produced alcohol but it was thought to be a purely chemical process and the yeast identified in beer and wine a product or catalytic agent of fermentation. The problem posed to Pasteur was to find the cause of sour wine and beer. Pasteur confirmed the presence of yeast in these cultures but also of bacteria. Using his experise on crystal structures, Pasteur was able to determine that yeast were responsible for the fermentation process and that bacteria present caused the souring of the alcohol. The solution was simple: boil the liquid for a few minutes and then add a pure culture of yeast to start the fermentation process (1-5).

Not only did this finding save the wine industry from the seemingly sporadic losses of batches, but it proved to Pasteur that the theory of spontaneous generation was wrong. Since ancient times it was believed that insects and (later) microbes arose from rotting matter as a biproduct. It was clear to Pasteur that microbes were present in the air and on the surface of grapes in the vineyards and thus present in distilling cultures. In an exploratory experiment Pasteur found that city air grew more cultures than air from high altitudes. A simple, yet elegant, experiment followed that proved germ theory’s dominance over spontaneous generation. Pasteur sterilized a fermentable liquid in a flask. The neck of the flask was heated and bent into an s-shape and sealed. The solution remained sterile. After the neck tip was broken off the solution yet remained sterile as the particles in the air were trapped on the beads of water sticking to the glass neck. Only when the flask was tipped to allow the solution to contact the trapped particles in the neck did a culture grow (1-5).

The surgeon Joseph Lister, in England, embraced Pasteur’s find and sterilized the equipment and air in his operating room. This dramatically reduced fatalities and caused Lister to champion germ theory as well. And yet most scientists clung to spontaneous generation until the 1870s and 80s (1-5).

Pasteur continued his research, identifying diseased silk worms and the conditions that contribute to their condition, saving the French silk industry. He also used Robert Koch’s discovery of the spores that cause anthrax to develop a vaccine for farm animals. A public challenge in 1882 by veterinarian Rossignol was a success, with Pasteur showing that 25 vaccinated sheep survived anthrax infection while 25 unvaccinated sheep perished. The circus-like atmosphere only helped the case of germ theory; dispatches were sent around Europe detailing his success. The vaccine not only resulted in reducing the mortality rate of livestock to 1% but also in monetary savings to France over the next 10 years totalling an estimated $7 million francs (1-5).

Pasteur’s swan song a few years later was developing a vaccine for rabies. Initial experiments were in rabbits and dogs and involved drying and mincing infected animals’ spinal cords and injecting the material, on a graduated scale of least to most potent, under the skin of healthy animals over several days. At the end of the trial the treated animals were immune to rabies. The news traveled quickly and in 1886 Pasteur found himself in an ethical quandary. A young boy, Joseph Meister, had been bitten and mauled by a rabid dog. Although Pasteur had great success with animal vaccination he was not completely confident in the vaccine’s use for humans. The boy’s mother pleaded and Pasteur began the vaccine trial. Meister recovered completely (1-5).

This success led to the establishment of the famed Pasteur Institute in Paris, initially a hospital to treat human rabies (1-5). In 1895 Pasteur died after a series of strokes since his 40s. He was given a state funeral having contributed immeasurably to the health and industries of France and pioneering germ theory. Joseph Meister grew up to work as a gatekeeper at the Pasteur Institute (5). In 1940 Nazi invaders ordered Meister to open Pasteur’s crypt. Sadly, Meister refused and committed suicide.

1. http://www.bbc.co.uk/historic_figures/pasteur_louis.shtml
2. http://louisville.edu/library/ekstrom/special/pasteur/cohn.html
3. http://encarta.msn.com/text_761568595___0/Louis_Pasteur.html
4. http://www.fordham.edu/halsall/mod/1878pasteur-germ.html
5. http://elane.standford.edu/wilson/Text/5f.html

Six months’ exclusive breast feeding benefits infants’ health

Most people do not think of the industrial revolution when they think of the breast feeding-formula feeding debates but it is arguably the reason the discussion exists today (National Academy of Sciences, foodtimeline.org, wikipedia.com). In the early 19th century breast feeding was the norm around the world. Women who had difficulties with breast feeding found wet nurses for their infants or created homemade formulas. The 1845 advent of the rubber nipple was the first step toward the formula feeding boon of the 20th century. Enterprising budding industrialists introduced the first manufactured formulas in 1867, advertising them as equal or superior to breast milk (though later generations would repudiate these claims). Yet formula and the bottle would have remained the recourse for women who could not nurse or find a wet nurse had not two other major changes taken place. Perhaps the most critical change was in the minds of newly industrialized countries—namely the discovery and acceptance of germ theory. The desire to avoid potentially tainted milk combined with medicine’s endorsement of formula to change the tide against breast feeding. Yet more than half of the infants in the United States were still breast fed until the late 1920s/early 1930s when refridgeration became more common. By the 1950s breast feeding was summarily dethroned as the preferred method of infant feeding with the rise of commercialized formulas.

Breast feeding provides infants with more than energy (Fomon, Anderson et al.). Proteins, vitamins and minerals are used by the infant to grow and mature. Antibodies, growth factors and enzymes provided by the mother aid immunity, growth and development until the infant’s own systems mature. Lipids and neurotransmitters aid in brain development while other components of breast milk sharpen vision. Formulas have developed remarkably in the last 150 years but they do not provide all the beneficial components of breast milk nor do they necessarily provide them in a form usable by the infant. As the infant’s systems are developing some components of breast milk rely on other components for activation or digestion. Furthermore, while some doctors may prescribe, or at least be aware of a potential need for, vitamin K and iron to breast-fed infants (likely dependent on the mother’s own levels) most components are in the ratio needed by the infant at that stage of development, measurements that are often difficult to apply to formula ingredients.

The superiority of breast milk to formula is advocated by doctors today. Debates exist, however, on the duration and exclusivity of breast feeding. The World Health Organization (WHO) and American Academy of Pediatrics (AAP) both recommend exclusive breast feeding for the first 6 months (except in rare circumstances, discussed below). Exclusive not only means without formula supplementation but also without supplementation of other milks, liquids or solid foods. At 6 months of age solid foods can be introduced and fed along with breast milk until at least age 12 months (AAP) or 24 months (WHO). Neither organization makes overt recommendations on when to stop breast feeding, ie when breast milk is no longer providing what solid foods and the toddler’s body cannot, but simply recommend continuing as long as both mother and child desire it. Mothers in developing countries may find extra benefit in prolonged breast feeding due to the high risk of contaminated water and food that would more harshly effect toddlers over older children and adults with more mature organs.

Certainly today some women may find, as they have throughout history, extreme difficulty in nursing. For these women, adoptive parents, and others the formula options are quite good compared to earlier forms (Owen, Fomon, Kramer et al., Anderson et al.). Nutrients are made more bioavailable and mineral contaminants such as lead have been removed. Developed countries see little difference in formula-fed infants compared with breast-fed infants in the long run. Certainly breast-fed infants are ill less frequently and less seriously when they are ill (mostly applicable to respiratory and gastrointestinal disease) while being breast fed. They may also have a slight advantage with mental acuity (one study suggests an average of 3 points on an IQ test) and visual acuity in the long term. Although formula-fed infants are by no means absolutely doomed to a life poor health and average achievement, it is simply not a complete replacement for breast milk. Advantages to formula feeding over breast feeding exist for particular situation as well. For women who are on drugs, chemotherapy, radiation, are infected with HIV or TB, or have infants with a rare genetic disorder that prevents the digestion of breast milk formula is recommended by the AAP over breast milk. The WHO has similar recommendations but does point out that while HIV can be transmitted by breast feeding (from 5-20% transmission rate for some breast feeding to 30-45% transmission rate for 18-24 months of breast feeding) other immunological (including HIV) and nutritional benefits from breast milk will be lost. In the United States and other developed countries, as stated above, choosing formula may not present a long-term observable effect but in developing countries it could mean gambling with the child’s life as much as the risk of HIV infection.

Breast feeding is best for the mother and child (Ruowei et al., Fomon, Anderson et al., Hediger et al). It is the natural process both bodies desire and should be promoted over formula feeding in almost all cases in the US. Multiple studies have shown, however, that only approximately 71% of infants in the US are ever breast fed and only approximately 14% of these infants are breast fed exclusively for 6 months. The percentage of mothers who nurse has been increasing since the late 1960s. Most women who breast feed exclusively are white, at least 25 years of age, well-educated and reside on the west side of the country. Mothers who are black, young and without a high school diploma are most likely not to breast feed. While infants in low socioeconomic groups could benefit greatly from breast feeding over formula feeding the education and resources to breast feed, especially in single-parent homes, are lacking.

The emotional, biosocial, nutritional and developmental benefits to breast feeding over formula feeding are proven (Ruowei et al., Fomon). What remains is to provide viable options for women and infants for whom breast feeding is not an option and resources for working mothers to breast feed their infants for at least the first 6 months to a year. Widespread education and cultural shifts may be required as they were to make the shift to formula in the 19th and 20th centuries (Montagu).

National Academy of Sciences. Evaluating the Safety of New Ingredients, 2004.
WHO:  http://www.who.int/topics/breastfeeding/en/
 http://www.who.int/nutrition/publications/HIV_IF_guide_for_healthcare.pdf
AAP: http://aappolicy.aappublications.org/cgi/content/full/pediatrics%3b100/6/1035
 http://pediatrics.aappublications.org/cgi/content/abstract/112/5/1196
Foodtimeline.org
Wikipedia.com
Ruowei, L. et al. Changes in Public Attitudes toward Breastfeeding in the United States, 199-2003. Journal of the American Dietetic Association. Vol. 107. No. 1, 2007.
Montagu, M. Nature, Nurture and Nutrition. The American Journal for Clinical Nutrition. Vol. 5 No. 3, 1957.
Forman, M. et al. Exclusive breastfeeding of newborns among married women in the United States: the National Natality Surveys of 1969 and 1980. The American Journal for Clinical Nutrition. Vol. 42.  864-869, 1985.
Owen, G. Interaction of the infant formula industry with the academic community. The American Society for Clinical Nutrition. Vol. 46. 221-225, 1987.
Fomon, S. Reflections on infant feeding in the 1970s and 1980s. The American Journal for Clinical Nutrition. Vol. 46 171-182., 1987.
Anderson, J. et al. Breast-feeding and cognitive development: a meta-analysis. The American Journal for Clinical Nutrition. Vol. 70. 525-535, 1999.
Hediger, M. et al. Early infant feedign and growth status of US-born infants and children aged 4-71 mo: analyses from the third National Health and Nutrition Examination Survey, 1988-1994. The American Journal for Clinical Nutrition. Vol. 72. 159-167, 2000.
Kramer, M. et al. Infant growth and health outcomes associated with 3 compared with 6 mo of exclusive breastfeeding. The American Journal for Clinical Nutrition. Vol. 78. 291-295, 2003.

Obsessive-compulsive disorder is in my DNA

If I think back about it, I seem to remember that the sequencing of the human genome slightly predates the obsession with DNA in pop culture. I’m not thinking about actual scientific work related to DNA that pops up in newspapers every day but more the trend to use DNA as a scapegoat. Statements like: I can’t help that I’m a shopaholic, it’s in my DNA. As someone who actually knows a thing or two about DNA this tends to make my eye twitch. The human genome may be sequenced but not all of our genes have been identified. Even so I can say with fair certainty that there has not been sufficient evolutionary time for a shoe gene to develop.

I can ignore these statements and take them as they’re meant to be: a statement of a trait that the person perceives to be innate and unchangeable. The real problem I find is in movies and TV. Misrepresentation in film is by no means limited to biology but it does pull me out the moment. A second after the shudder runs through my body I wonder who actually learns these mistakes. I mean, I learned the definition of a score from the recitation of the Gettysburg Address in Bill and Ted’s Excellent Adventure so someone could believe that genes can skip generations or disappear completely as claimed in 28 Weeks Later, right? I know what they’re getting at, that gene *expression* might be recessive and not shown in the offspring. Or that the gene may have been mutated or lost in an individual’s somatic cells and not their gametes (sex cells) (much like that which causes a melanoma from too many summers at the beach) and hence hereditable.

I don’t meant to pick on one film, it is, certainly, not the only, or even most blatant, offender. Red Planet, with Val Kilmer and Benjamin Bratt, had several references to nematodes. Unfortunately for them nematodes are a type of worm. The critters in question were not. Clearly a checkable fact. CSI Miami pushes the boundaries of believable at times, all the more dangerous for their otherwise fairly accurate portrayal of the biology of forensics. As an example, in one episode epithelial skin cells were removed from rough upholstery on a car seat and used to identify an assailant. While it is technically possible to get enough DNA from a few cells to identify a person it is difficult. Moreover, the outermost skin cells are dead and do not contain a nucleus. The chances that the cells that remained on the upholstery after the car crashed were from a deeper, nucleated skin layer are, well, the kind of odds Hollywood makes good on.

The fact is that errors are everywhere in movies and the only people who usually care are those who know they’re mistakes. Errors may happen even after fact checking (I think I’d forgive the incorrect phase of the moon during the moon landing in Apollo 13) but films that are not specifically relying on a fantasy element should make sure that their basic facts are sound. Have all the bubbling beakers you want if that’s your aesthetic but gravity doesn’t let up on Tuesday afternoons, Amelia Earhart wasn’t born in 1987 and *individuals* don’t evolve. Just ask Wikipedia.

I suppose I should take the stance of some historians on the movie Troy. While factually inaccurate in many ways the movie was viscerally correct and, more importantly, had inspired many college students to register for history courses. I just don’t think 28 Weeks Later is going to cause a surge in students registered for virology.