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Young female athletes at risk, say US experts
SCIENCE AND MEDICINE
Vitamin C restores early coronary impairments in smokers igarette smoking strikingly impairs coronary microcirculation and interferes with the regulation of myocardial blood flow (MBF), experts report this week. However, these derangements are reversed by acute administration of vitamin C. Smoking is thought to cause oxidative damage to vascular endothelium, but the exact way in which the habit predisposes to coronary artery disease is unclear. So, Philipp Kaufmann (University Hospital, Zurich, Switzerland) and co-workers studied how smoking affects MBF and whether impairments respond to antioxidant treatment. The team used positron-emission tomography to assess MBF at rest and during adenosine-induced hyperaemia in 11 healthy smokers and eight non-smokers. Measurements were repeated after infusion of 3 g vitamin C.
C
At baseline, coronary flow reserve—the ratio of hyperaemic to baseline MBF—was 21 % lower in smokers. Subsequent vitamin C infusion normalised MBF and coronary flow reserve in smokers, but had no effect in non-smokers. The study is “the first to demonstrate that the noxious prooxidant effects of smoking extend beyond the epicardial arteries to the coronary microcirculation and affect the regulation of MBF”, the authors claim. Paolo Camici (Hammersmith Hospital, London, UK) believes that these effects are “the first derangements in the coronary circulation” caused by smoking. And, he explains, acute restoration with vitamin C suggests that these derangements are not due to structural damage but are “purely functional”, caused at least partly by increased oxidative stress.
Smokers have reduced plasma and tissue concentrations of vitamin C, so smoking leads to both “decreased natural antioxidants and an increased oxidative burden”, explains Camici. With acute administration of such a large dose, vitamin C is most likely to have a pharmacological antioxidant action, he proposes, rather than restoring vitamin C concentrations. Camici suggests that a large-scale trial is warranted to test whether daily oral vitamin C supplementation can prevent coronary artery disease in smokers. For now, increasing dietary intake of fresh fruit and vegetables remains sound advice for smokers, but Camici stresses that “it is premature to extrapolate from our study to encourage people who smoke to use vitamin C as a drug”. Kelly Morris
Neurologists determine the effect of migraine on quality of life
T
wo population-based studies report this week that individuals with migraine consistently report lower mental, physical, and social well-being than do unaffected controls. The two surveys, one carried out by Dutch researchers and one by researchers in the USA and UK, used health-related quality of life questionnaires (HRQoL) to study the general health perception of individuals with migraine who had not been to see a physician. “This is the bigger picture of migraine, as prior studies have focussed on the socio-economic impact of migraine. Quality of life
measures the impact in human terms”, says Gisela Terwindt (University Medical Centre, Leiden, Netherlands), lead investigator of the Dutch study (Neurology 2000; 55: 624–29). “These data clearly show that migraine patients who do not seek medical help also suffer a substantial impact on their quality of life, even when compared with other chronic conditions [asthma and chronic musculoskeletal pain]”. The US/UK study (Neurology 2000; 55: 629–35) was also able to confirm that migraineurs are more likely to be depressed than controls
(47% versus 17%). However, the data appear to indicate that migraine and depression have an independent impact on quality of life. “It seems logical that migraine patients would be depressed because of their pain”, says Richard Lipton (Albert Einstein College of Medicine, Bronx, NY) and lead author of the US/UK study “But it goes the other way too—depressed patients are more likely to have migraine. We think the two disorders must have a common neurobiology.” Wim Weber
Young female athletes at risk, say US experts irls and adolescent females who participate regularly in sports are at risk for disordered eating, menstrual dysfunction, and decreased bone mineral density, warns the American Academy of Pediatrics (AAP) this week. Physicians are urged to monitor young athletes for the three disorders, which together are referred to as the “female athlete triad”. The number of young female athletes at risk is growing because of the “burgeoning emphasis” in the USA on involving girls in sports, says AAP spokesperson Eric Small. “Ten years ago, there were three times as many sports programs for boys as for girls; today, it’s closer to 50–50.
G
THE LANCET • Vol 356 • September 16, 2000
Participants in year-round sports that judge competitors by how they look, such as gymnastics and dance, are particularly at risk”, he notes. Physicians should be alert to injuries that don’t heal—eg, shin pain that lasts several weeks instead of a few days and stress fractures. “You can’t just treat the injury; you have to talk to the patient, family members, and coach about nutrition and the menstrual cycle”, asserts Small. The AAP policy recommends that physicians do pre-participation physical examinations and assessments of dietary habits, exercise intensity, and menstrual history, and encourage adequate caloric intake by emphasis-
ing that too few calories can harm performance. Adolescents with menstrual disorders should be medically evaluated (Pediatrics 2000; 106: 610–13). “This is great—exactly the kind of information that needs to get out there”, comments Margaret Putukian, spokesperson for the American College of Sports Medicine. “Many of the college athletes I work with have been told for years that having an out-of-whack menstrual cycle is ‘no big deal’—that it’s just because they’re active. And I have to tell them no, it’s not okay. It’s a problem, and we have to deal with it.” Marilynn Larkin
1007
For personal use only. Not to be reproduced without permission of The Lancet.
Vitamin C restores early coronary impairments in smokers igarette smoking strikingly impairs coronary microcirculation and interferes with the regulation of myocardial blood flow (MBF), experts report this week. However, these derangements are reversed by acute administration of vitamin C. Smoking is thought to cause oxidative damage to vascular endothelium, but the exact way in which the habit predisposes to coronary artery disease is unclear. So, Philipp Kaufmann (University Hospital, Zurich, Switzerland) and co-workers studied how smoking affects MBF and whether impairments respond to antioxidant treatment. The team used positron-emission tomography to assess MBF at rest and during adenosine-induced hyperaemia in 11 healthy smokers and eight non-smokers. Measurements were repeated after infusion of 3 g vitamin C.
C
At baseline, coronary flow reserve—the ratio of hyperaemic to baseline MBF—was 21 % lower in smokers. Subsequent vitamin C infusion normalised MBF and coronary flow reserve in smokers, but had no effect in non-smokers. The study is “the first to demonstrate that the noxious prooxidant effects of smoking extend beyond the epicardial arteries to the coronary microcirculation and affect the regulation of MBF”, the authors claim. Paolo Camici (Hammersmith Hospital, London, UK) believes that these effects are “the first derangements in the coronary circulation” caused by smoking. And, he explains, acute restoration with vitamin C suggests that these derangements are not due to structural damage but are “purely functional”, caused at least partly by increased oxidative stress.
Smokers have reduced plasma and tissue concentrations of vitamin C, so smoking leads to both “decreased natural antioxidants and an increased oxidative burden”, explains Camici. With acute administration of such a large dose, vitamin C is most likely to have a pharmacological antioxidant action, he proposes, rather than restoring vitamin C concentrations. Camici suggests that a large-scale trial is warranted to test whether daily oral vitamin C supplementation can prevent coronary artery disease in smokers. For now, increasing dietary intake of fresh fruit and vegetables remains sound advice for smokers, but Camici stresses that “it is premature to extrapolate from our study to encourage people who smoke to use vitamin C as a drug”. Kelly Morris
Neurologists determine the effect of migraine on quality of life
T
wo population-based studies report this week that individuals with migraine consistently report lower mental, physical, and social well-being than do unaffected controls. The two surveys, one carried out by Dutch researchers and one by researchers in the USA and UK, used health-related quality of life questionnaires (HRQoL) to study the general health perception of individuals with migraine who had not been to see a physician. “This is the bigger picture of migraine, as prior studies have focussed on the socio-economic impact of migraine. Quality of life
measures the impact in human terms”, says Gisela Terwindt (University Medical Centre, Leiden, Netherlands), lead investigator of the Dutch study (Neurology 2000; 55: 624–29). “These data clearly show that migraine patients who do not seek medical help also suffer a substantial impact on their quality of life, even when compared with other chronic conditions [asthma and chronic musculoskeletal pain]”. The US/UK study (Neurology 2000; 55: 629–35) was also able to confirm that migraineurs are more likely to be depressed than controls
(47% versus 17%). However, the data appear to indicate that migraine and depression have an independent impact on quality of life. “It seems logical that migraine patients would be depressed because of their pain”, says Richard Lipton (Albert Einstein College of Medicine, Bronx, NY) and lead author of the US/UK study “But it goes the other way too—depressed patients are more likely to have migraine. We think the two disorders must have a common neurobiology.” Wim Weber
Young female athletes at risk, say US experts irls and adolescent females who participate regularly in sports are at risk for disordered eating, menstrual dysfunction, and decreased bone mineral density, warns the American Academy of Pediatrics (AAP) this week. Physicians are urged to monitor young athletes for the three disorders, which together are referred to as the “female athlete triad”. The number of young female athletes at risk is growing because of the “burgeoning emphasis” in the USA on involving girls in sports, says AAP spokesperson Eric Small. “Ten years ago, there were three times as many sports programs for boys as for girls; today, it’s closer to 50–50.
G
THE LANCET • Vol 356 • September 16, 2000
Participants in year-round sports that judge competitors by how they look, such as gymnastics and dance, are particularly at risk”, he notes. Physicians should be alert to injuries that don’t heal—eg, shin pain that lasts several weeks instead of a few days and stress fractures. “You can’t just treat the injury; you have to talk to the patient, family members, and coach about nutrition and the menstrual cycle”, asserts Small. The AAP policy recommends that physicians do pre-participation physical examinations and assessments of dietary habits, exercise intensity, and menstrual history, and encourage adequate caloric intake by emphasis-
ing that too few calories can harm performance. Adolescents with menstrual disorders should be medically evaluated (Pediatrics 2000; 106: 610–13). “This is great—exactly the kind of information that needs to get out there”, comments Margaret Putukian, spokesperson for the American College of Sports Medicine. “Many of the college athletes I work with have been told for years that having an out-of-whack menstrual cycle is ‘no big deal’—that it’s just because they’re active. And I have to tell them no, it’s not okay. It’s a problem, and we have to deal with it.” Marilynn Larkin
1007
For personal use only. Not to be reproduced without permission of The Lancet.