Journal Club

JOURNAL CLUB

A new light on night lights and myopia

Last year investigators reported a strong association between myopia in children and their exposure to night-time lighting during the first two years of life (Quinn GE et al: Nature 1999; 399:113). We summarized these findings in Journal Club in July 1999. Now another group of investigators reports that they have been unable to confirm the results of Quinn and colleagues. Instead, they find that myopic parents are more likely to have myopic children and to use night-time lighting aids than are parents who do not have myopia. The investigators note that the earlier study included no information about the refractive status of the subjects' parents.

Investigators divided the 213 subjects, whose mean age was 11 years, into two groups: those who were myopic and those who were not. They asked parents about how they lit their children's rooms at night, using the same questions as Quinn and colleagues, plus a few others. Of the children who slept with night lights before 2 years of age, 20% were myopic. Incidence of myopia also was 20% in children who slept in the dark. None of the few children who slept in a fully lit room were myopic. Results were not related to either the age at which myopia began or its severity.

Families in which both parents were myopic used ambient lighting at night significantly more than those with one myopic parent or none. Children with two myopic parents were far more likely to be nearsighted than children with one or no myopic parent (Gwiazda J et al: Nature 2000;404[6774]:144).

Commentary: Like its predecessor, this report suffers from dependence on parental recall of lighting practices from as long ago as 22 years. These authors were unable to find a link between night-light use and myopia, even before adjusting for parental myopia. Their alternate theory, that myopic parents were more likely to use night lights and to have myopic children, makes more biologic sense. So leave the nursery light on if you want. At the very least, you may avoid stubbing a toe.

Now to the videotape!

In video narratives they recorded themselves, children and adolescents with asthma revealed aspects of their medical history they failed to mention, or contradicted, in standard medical histories. Investigators obtained comprehensive asthma-specific medical histories from 20 asthma patients from 8 to 25 years old. They then trained these young people to use video camcorders and asked them to record visual narratives of how they lived with and managed their asthma for four to eight weeks. The young people included tours of their home and neighborhood, documented activities of daily living, such as meals, school, and play, and showed how they managed their asthma. Participants also set up the camcorder each evening and spoke to it directly about the events of the day and their observations, thoughts, and feelings.

A trained observer screened these narratives and completed the initial medical history solely from this viewing, evaluating exposure to environmental risk factors, medication use, and other factors relevant to asthma management. All participants reported specific environmental triggers for their asthma, which they claimed to avoid. Yet the video narratives documented the presence of one or more of these triggers for 19 of the 20 participants. One youngster, for example, said that her mother's cats were never allowed in her bedroom, but the video showed a kitten sleeping in her bed. Although 19 study subjects identified secondhand smoke as a trigger and said that they had eliminated it from their environments, 12 revealed others smoking around them in their video narratives. Inappropriate uses of asthma medications were observed in 16 of the youngsters, exceeding prescribed dosages of quick-relief medications or using an ineffective technique with a metered dose inhaler, for example. Investigators concluded that video assessment can enhance clinical data gathering, guide the development of more effective and sensitive management strategies, and educate clinicians about the realities of living with illness (Rich M et al: Pediatrics 2000;105:469).  

Commentary: The authors asked these patients to use the video cameras to teach their clinicians about asthma, and they have done just that. These patient-generated videos may hold the answer to the puzzle of rising mortality and morbidity from asthma despite advances in understanding and treatment of the disease. We study asthma and other chronic diseases in the sterile context of offices and hospitals and rely on information from patients who are often forgetful or evasive. By using real-world videos, the authors remind us that the fight against chronic disease takes place on the patients' home court.

Preschoolers on Ritalin: An alarming increase

The number of children from 2 to 4 years old prescribed stimulants, antidepressants, and other psychotropic drugs rose dramatically from 1991 to 1995, researchers report. Investigators based their findings on prescription records of more than 200,000 preschoolers enrolled in two state Medicaid programs, one in the Midwest and the other in the mid-Atlantic region, or a health maintenance organization in the Northwest. They examined data for three psychotropic medication classes: stimulants (methylphenidate and others); antidepressants (SSRIs, tricyclics, and others); and neuroleptics. Stimulants, overwhelmingly methylphenidate (Ritalin), were the leading treatment. Their use in preschoolers increased twofold or threefold in the three health plans during the four-year study period. Use of clonidine and antidepressants also increased considerably in all three sites, while neuroleptic use rose only slightly (Zito J et al: JAMA 2000;283:1025).

Commentary: What is a 3-year-old learning in preschool that demands enough attention to justify treatment for ADHD? Before playing hard ball with Ritalin, we can almost always hold off until the child enters big-league first and second grade.

Deaths in car accidents neither rise nor fall

An analysis of Centers for Disease Control and Prevention data on motor vehicle fatalities from 1994 to 1998 shows little change during this period in the death rate, restraint use, and seating position of children age 4 to 8 who were in a motor vehicle crash with one or more fatalities. Of 14,411 such children, 2,549 (17.7%) died. The number of deaths was about 500 each year of the four-year period. In 1994, 35.2% of fatally injured children used restraints; in 1998 restraint use was 38.1%. The proportion of fatally injured children seated in the back seat of a motor vehicle in a crash also remained quite constant: 50.1% in 1994 and 53.7% in 1998. Data used in the analysis were obtained from the Fatality Analysis Reporting System (MMWR 2000;49[7]:135).

Commentary: In an accompanying commentary MMWR editors highlight two practices associated with motor vehicle deaths in this age group. The first is failure to use booster seats for 4- to 8-year-olds after they outgrow child safety seats. Experts recommend that children this age stay in a belt-positioning booster until they are 58 inches and 80 pounds. Second is placement of children in a front seat of the vehicle. Placement in the back seat decreases risk of childhood vehicular fatality by 30% or more.

A single steroid injection for asthma attacks?

A single intramuscular (IM) injection of dexamethasone acetate appears to be as effective as a five-day course of oral prednisone for treating young children with mild to moderate exacerbations of asthma. Investigators, seeking an alternative to oral prednisone, which many young children balk at taking, compared the two treatments in 32 children who required corticosteroids to treat asthma exacerbations. The children, who were outpatients at a tertiary care medical center, ranged in age from 6 months to 7 years. They received either a single dose of IM dexamethasone acetate (~1.7 mg/kg) or oral prednisone (~2 mg/kg/d) for five days. Parents kept an asthma symptom diary, used to measure changes in asthma signs or symptoms (clinical asthma score), from days one through five of treatment.

Clinical asthma scores improved significantly in both groups during the first five days of therapy, with no notable difference between the two groups. Three children refused more than three quarters of their oral prednisone doses, and another four missed from one third to half the doses despite their parents' best efforts. The IM injection caused no complications, and about 70% of parents in both groups said they would choose it to treat their child's next asthma attack (Gries DM et al: J Pediatr 2000;136:298).  

Commentary: The IM injection may be an alternative for outpatient asthmatics who refuse foul-tasting oral steroids. The authors are careful to point out that the IM preparation used was dexamethasone acetate, not the shorter-acting dexamethasone phosphate commonly used for treating croup. They also clearly state that these findings should not be extrapolated to children with severe asthma exacerbations that require hospitalization. That's a different study, which needs to be done.

Early high-dose treatment best in hypothyroidism

A retrospective study conducted in the Netherlands suggests that infants with congenital hypothyroidism achieve normal psychomotor development when they are given a high initial dose of levothyroxine (thyroid hormone replacement) before they are 13 days old. Investigators treated 61 patients who had congenital hypothyroidism with levothyroxine. They formed eight treatment groups based on severity of illness (27 with severe illness and 34 with mild), when treatment was begun (before or after 13 days of age), and the size of the initial dose of levothyroxine (a high dose of more than 9.5 µg/kg/d or a low dose of less than 9.5 µg/kg/d).

When the infants were from 10 to 30 months old, investigators measured their mental development and psychomotor development, using standard tests. Of the infants with severe congenital hypothyroidism, only the group treated early with the higher dose of levothyroxine had mental development scores comparable to those of the reference population and the infants with mild disease. By contrast, all infants with mild congenital hypothyroidism had normal mental development, except those in the group treated late with a low initial dose of levothyroxine. The authors concluded that infants with congenital hypothyroidism achieve normal intellectual development regardless of the severity of their disease if treatment with levothyroxine is begun before 13 days and the initial dose is above 9.5 µg/kg/d (Bongers-Schokking JJ et al: J Pediatr 2000;136:292).  

Commentary: This is a small retrospective study, but it deserves some attention. If these investigators are right, they set a high standard for those who coordinate newborn screening: completion of the initial screen and initiation of therapy within the first two weeks of life. The dose of levothyroxine suggested here (9.5 µg or greater/kg/d) is at the high end of the 8 to 10 µg/kg/d range suggested in the newest edition of the Harriet Lane Handbook.

Also of note

A marker for hypertrophic pyloric stenosis. Hypoplasia or absence of the mandibular frenulum is commonly associated with infantile hypertrophic pyloric stenosis, a new study finds. The mandibular frenulum is a normal midline craniofacial structure extending from the vestibular mucosa of the lower lip to the gingival mucosa of the lower jaw. Investigators compared clinical data for 25 infants with surgically confirmed infantile hypertrophic pyloric stenosis and 319 controls with matching gestational ages. Of the 25 subjects, 23 (92%) had a hypoplastic or absent mandibular frenulum, compared with five (1.6%) of the controls (De Felice C et al: J Pediatr 2000;136:408).  

Smoke and fungus tied to pulmonary hemorrhage. A case report on a 40-day-old boy who developed a life-threatening pulmonary hemorrhage supports a previously reported link between this condition and exposure to indoor fungus growth and tobacco smoke. The infant visited his grandfather's house for two weeks, then traveled home in a train car that was periodically permeated with tobacco smoke. He developed the pulmonary hemorrhage several hours after boarding the train. An investigation of the home disclosed mold in the basement and in the paint and crevices of the walls below the windows in the room where the infant slept. Two fungi associated with mycotoxin production were cultured from surface samples: Penicillium (possibly Penicillium purpurogenum) and a species of Trichoderma. No association was found between the hemorrhage and infection, trauma, a foreign body, congenital heart defect, congenital lung abnormality, bleeding diastasis, or cow-milk protein allergy (Novotny WE et al: Arch Pediatr Adolesc Med 2000;154:271).

DR. BURKE, Section Editor for Journal Club, is Chairman of the Department of Pediatrics at Saint Agnes Hospital, Baltimore. He is a Contributing Editor for Contemporary Pediatrics.

CLINICAL TIP
Watching warts go up in "smoke"

After I am finished treating a plantar wart with liquid nitrogen, I pour a small amount of water (3 to 5 mL) into the polystyrene plastic cup containing the liquid nitrogen. The resulting billow of "smoke" delights children. They may even look forward to the next treatment because of this "magic trick." Just be careful to hold the cup away from the patient. The contents could splatter if the water is added too forcefully.

Here's another trick to ease treatment of warts: Apply a small amount of KY jelly over the pared down wart before freezing it. The jelly prevents cotton fibers on the applicator stick from adhering to the wart and causing bleeding when you apply the liquid nitrogen. The jelly does not interfere with freezing.

Brian Yagoda, MDWaukesha, WI

Do you have a Clinical Tip to share with colleagues? Let us know; we'll pay $50 for each item accepted for publication. Tips sent by mail should be addressed to Molly Frederick, Clinical Tips Editor, Contemporary Pediatrics, 5 Paragon Drive, Montvale, NJ 07645-1742. If you submit by E-mail (Molly.Frederick@medec.com), please include your mailing address.

CLINICAL TIP
A winning combination for med storage

Whenever I discuss poison control with parents, I urge them to store all medications in a locked cabinet. For both home and travel I suggest a simple system that most families can afford: a tackle box or tool box secured with a combination lock. Combination locks are better than locks with keys because there is no key to get lost or fall into little hands.

When it comes time to travel, the medications are already packed and only need to be carried to the car. A locked box is particularly helpful when living out of suitcases with small children because parents know at a glance where the medicines are—and that they are secure from curious little ones. Many parents in my practice say that they have followed this advice. That's the best endorsement I know.

Susan C. Hendrickson, MDBay City, MI 

Do you have a Clinical Tip to share with colleagues? Let us know; we'll pay $50 for each item accepted for publication. Tips sent by mail should be addressed to Molly Frederick, Clinical Tips Editor, Contemporary Pediatrics, 5 Paragon Drive, Montvale, NJ 07645-1742. If you submit by E-mail (Molly.Frederick@medec.com), please include your mailing address.

CLINICAL TIP
Thumbs up for smooth injections

While drawing up a dose of Varivax, I noticed how difficult it is to pass the syringe needle through the frozen rubber stopper of the vial. I also observed that the process seemed to dull the needle, making the injection more painful than necessary.

Now, before drawing up the dose of vaccine, I rub my thumb over the top of the rubber stopper for about 15 seconds. Then I clean the stopper with an alcohol swab. Result: The needle slides through the rubber with minimal resistance and remains sharp so that the injection is much easier on the patient.

Burt E. Minaker, MDAttleboro Falls, MA  

Do you have a Clinical Tip to share with colleagues? Let us know; we'll pay $50 for each item accepted for publication. Tips sent by mail should be addressed to Molly Frederick, Clinical Tips Editor, Contemporary Pediatrics, 5 Paragon Drive, Montvale, NJ 07645-1742. If you submit by E-mail (Molly.Frederick@medec.com), please include your mailing address.

CLINICAL TIP
Exam rooms with something special

Instead of putting toys in the pediatric examining rooms of our clinic I've decorated the walls and ceilings with self-adhesive glow-in-the-dark stars—up to 1,000 stars per room. We use the stars for hidden messages and to make constellations such as the Big Dipper. Parents and children love them. When I walk into a star-filled room, the family is relaxed, sitting in the dark enjoying the view.

Children often ask to be put in the star rooms. Parents like the stick-ons so much that they want to know where I purchased them so they can get some for home use. The stars are inexpensive—200 to 400 for about $4.00. They are available at stores such as The Nature Company and Target. They are also easy to remove without damaging paint or wallpaper.

In exam rooms with windows, where the star stick-ons don't show up well, we have tiny bubble blowers for children to play with. The detergent in the bubble solution discourages any spread of germs and the plastic containers sterilize easily.

Cyd Charisse Williams, MD Chaska, MN

Do you have a Clinical Tip to share with colleagues? Let us know; we'll pay $50 for each item accepted for publication. Tips sent by mail should be addressed to Molly Frederick, Clinical Tips Editor, Contemporary Pediatrics, 5 Paragon Drive, Montvale, NJ 07645-1742. If you submit by E-mail (Molly.Frederick@medec.com), please include your mailing address.

 

Marian Freedman. Journal Club. Contemporary Pediatrics 2000;5:159.