The interrelationships of body fat, exercise, and hormonal status and their impact on reproduction and bone health.
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Adipose Tissue↗
Biomedical subjects
M P Warren
Publications and source records attributed to M P Warren.
Clinical review 40: Amenorrhea in endurance runners.
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Amenorrhea↗
Total body bone density in amenorrheic runners.
Many studies have suggested that the positive effect of running on bone mass does not fully compensate for the negative effects of athletic amenorrhea. These studies have made this conclusion based on measurements of bone at a limited number of sites. This study used dual-photon absorptiometry to measure bone mineral content and bone mineral density in the total body as well as in several regions in amenorrheic runners (N = 13), eumenorrheic runners (N = 13), and sedentary controls (N = 12). The subjects were 21-35 years old. Runners had run at least 40 km/week for at least the past 3 years. Controls had body mass indices similar to those of the runners. The amenorrheic women had significantly lower values for total bone mineral content (P = .01), total bone mineral density (P = .04), and total bone mineral content as a percent of normal values (P = .04) than eumenorrheic women, but they were not significantly different from the controls. When total bone mineral content and total bone mineral density were adjusted for body weight, there were no significant differences among the groups. The eumenorrheic subjects had significantly greater bone mineral density in the trunk than the amenorrheic women; eumenorrheics and controls had significantly greater bone mineral density in the spine compared with amenorrheics. Lumbar spine bone mineral density showed a trend toward greatest values for controls and lowest for amenorrheic women (P = .069), although this measurement is relatively imprecise. Arms and legs showed no significant differences among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Absorptiometry, Photon↗
The reproductive system and exercise in women.
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Exercise↗
Lack of bone accretion and amenorrhea: evidence for a relative osteopenia in weight-bearing bones.
Bone mineral density (BMD) was studied in young exercising amenorrheic girls to determine if density was compromised and the change related to injury. Ninety-eight volunteers (professional ballet dancers and controls) were studied in a cross-sectional study. Dancers and controls were further subdivided into normally cycling and amenorrheic subjects. Amenorrhea significantly lowered bone density of the spine (P less than 0.0001), wrist (P less than 0.03), and metatarsal (P less than 0.01); effects on the wrist were eliminated by controlling for age while controlling for weight eliminated all effects of amenorrhea at three sites. BMD of the metatarsal, a weight-bearing bone, showed an interaction between amenorrhea and dancing (exercising) P less than 0.035); surprisingly, dancing was associated with a further lowering of bone density. This interaction was eliminated when controlling for age, but not when controlling for weight. With multiple comparisons of the groups, spine, wrist, and metatarsal bone density was significantly lower in amenorrheic dancers when compared to normal dancers (P less than 0.05), even when controlling for age and weight in the metatarsal (P less than 0.05), and age in the spine (P less than 0.05). Estradiol levels correlated with bone density of both the wrist and the spine (r = 0.25, r = 0.23, P less than 0.02). Metatarsal density correlated with estradiol levels only in the dancers (r = 0.34, P less than 0.02). The only variable found to correlate with the occurrence of stress fractures was age of menarche. This was also the only variable of 9 (BMD of the wrist, spine or foot, calories ingested and expended, amount of calcium ingested, involvement in high energy activity, age of menarche or presence of amenorrhea) to predict stress fractures. Thus, BMD is significantly affected by the presence of amenorrhea but the effects are generally weight dependent. The compensatory increase in bone density generally seen in stressed bones, such as the metatarsal in ballet dancers, is deficient in amenorrheic premenopausal women even when controlling for weight but this effect may be age and estrogen dependent. Bone mass may not accumulate in the same manner in adolescents as in the mature women, thus putting them at risk for injury.
Adolescent↗
Changes in salivary antipyrine pharmacokinetics during adolescence, correlated with age, hormonal levels and Tanner stage.
To evaluate the effect of puberty on antipyrine metabolism, we measured antipyrine pharmacokinetics in 17 healthy subjects aged 6-21 years. The subjects received a single oral dose of antipyrine, 18 mg/kg. Salivary antipyrine levels were determined 3, 6, 9, 12 and 24 h after dosing. Age, weight, body surface area and Tanner stage were highly intercorrelated. Volume of distribution (liters) was highly correlated with all of these factors. The weight-corrected clearance of antipyrine declined significantly with age (r = 0.55, p less than 0.025). Patients were classified as immature and other based on serum hormone levels (immature = females with serum estradiol less than 25 pg/ml and males with serum testosterone less than 25 ng/dl). The uncorrected antipyrine clearance was significantly lower in the immature group (mean +/- SD 22.65 +/- 6.04 ml/min) than in others (mean +/- SD 41.30 +/- 13.26; p less than 0.01). This difference disappeared when the weight-corrected antipyrine clearance was compared for these two groups. The change in uncorrected antipyrine clearance with sexual maturation appeared to be due to increased body size, probably related to the adolescent growth spurt.
Adolescent↗
Resting metabolic rate and energy balance in amenorrheic and eumenorrheic runners.
This study investigated metabolic and nutritional factors in association with athletic menstrual dysfunction (AMD). Three groups of women were studied: amenorrheic runners (amenorrheic), eumenorrheic runners (eumenorrheic), and eumenorrheic sedentary controls (sedentary). Amenorrheic and eumenorrheic were similar in age, weight, percent body fat by hydrodensitometry, training pace and mileage, best 10 km race time, years running, and maximal oxygen consumption. When adjusted for body weight or for fat-free mass by analysis of covariance, RMR was significantly lower in amenorrheic than in eumenorrheic and sedentary. The daily caloric intakes of the groups did not differ significantly, but the amenorrheic scored significantly higher than the eumenorrheic and sedentary on a scale of aberrant eating patterns. Amenorrheic high mileage runners seem to have a less adequate diet than eumenorrheic runners but appear to maintain energy balance and stable weight through a reduction in RMR.
Adaptation, Physiological↗
Exercise in women. Effects on reproductive system and pregnancy.
Exercise may have a significant effect on the reproductive system in women; however, it is doubtful if exercise alone causes the hypothalamic amenorrhea, which is probably multifactorial in origin. Pregnancy is also affected by exercise, although long-term or deleterious effects have not been documented.
Bone Diseases↗
Nutrition and the incidence of stress fractures in ballet dancers.
The effects of nutrition on the incidence of stress fractures among classical ballet dancers were studied. Ten dancers with stress fractures were compared with a group of dancers without stress fractures and a group of nondancing control subjects. Subject pairs were matched for age, weight, and height. Specific nutrient intake and eating patterns were thus isolated to determine if dietary patterns could account for the incidence of stress fractures among these dancers. The majority (80%) of the 10 dancers with recent stress fractures had weights less than 75% of ideal (p less than 0.05) and showed a greater incidence of eating disorders (p less than 0.05). This group also showed a lower fat intake and a higher intake of low-calorie food (p less than 0.05). Menstrual patterns and bone density studies of the wrist, foot, and spine did not differ among the three groups, showing that stress fractures were significantly associated with a more-restrictive diet.
Adolescent↗
Ototoxicity of preradiation cisplatin for children with central nervous system tumors.
From March 1984 through March 1989 we performed 235 audiometric tests on 39 children with malignant brain tumors who were treated with cisplatin 100 mg/m2 every 3 weeks for three courses and vincristine weekly for 9 weeks followed by cranial irradiation. Twenty-eight of the 39 children had sufficient serial testing for evaluation of ototoxicity secondary to cisplatin. Following the third cisplatin treatment (300 mg/m2 cumulative dose), 20% of the assessable children had hearing loss limited to the high frequencies of 6,000 to 8,000 Hz, 16% had hearing loss beginning at 3,000 to 4,000 Hz, and three children (11%) had loss within the speech frequencies beginning at 1,000 to 2,000 Hz. Eighteen of 19 children (95%) who were evaluated comparatively at a median of 15 months following radiation showed no significant change from preradiation testing. There was no correlation between hearing loss and patient age. We conclude that cisplatin ototoxicity was acceptable and that radiation therapy does not increase the ototoxicity of cisplatin when the drug is given before, instead of following, cranial irradiation.
Adolescent↗
Effects of hormonal status on bone density in adolescent girls.
Few data are available on bone density in late adolescence. We studied factors affecting peak bone density in females. Forty-three white girls, aged 13-20 yr, were studied. Integrated estrogen exposure over the pubertal years was obtained by a score based on physiological events known to reflect circulation estrogen levels. The subjects were selected to provide great variation in estrogen exposure. Bone mineral density (BMD) was measured by single photon absorptiometry (midradius) and dual photon absorptiometry (spine and first metatarsal of the foot). Weight, estrogen score, and testosterone levels were highly correlated with BMD of the spine, wrist, and foot (P less than 0.05). Age correlated positively only with the BMD of the wrist. Twenty-four girls reaching ages 18-20 yr in the 2 yr of observation were divided into groups reflecting low (less than 24), medium (25-48), and high (greater than or equal to 49) estrogen exposure. The lowest scoring groups had the lowest spine and wrist BMD (P less than 0.05). This group weighed less and had lower weight to height ratio (P less than 0.05), the lowest weight (P less than 0.05) during adolescence, the highest age of menarche, and the highest amount of fiber in the diet (P less than 0.05). These subjects were separated into low and high BMD groups. Those subjects with the lowest values for spine, wrist, and foot were found to have significantly lower estrogen exposure scores and lower weight/height ratios; in addition, low BMD of the foot was associated with higher activity levels. Thus, wrist and spine BMD are affected by estrogen exposure during adolescence and weight; foot BMD, in addition, was negatively affected by activity, suggesting that bone mass in the active adolescent is affected by the absence of estrogen exposure.
Absorptiometry, Photon↗
Femoral head collapse associated with anorexia nervosa in a 20-year-old ballet dancer.
Femoral head collapse occurred in a 20-year-old ballet dancer with anorexia nervosa. The patient developed anorexia nervosa at the age of 11 years and had short stature. The condition never resolved, and she developed pain and stiffness in the right hip at the age of 18 years, with documentation of femoral head collapse on roentgenograms a year later. The patient had delayed pubertal maturation with a bone age of 13 years, primary amenorrhea, and hypoestrogenism. Evaluation for metabolic bone disease was negative, and dual-photon absorptiometry showed significantly decreased bone mass with a bone biopsy revealing only diffuse osteoporosis. Possible etiologic mechanisms of osteonecrosis including repetitive microtrauma and various factors predisposing to femoral head collapse in young women required further investigation.
Adult↗
Effects of space travel on reproduction.
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Animals↗
Biological and social contributions to negative affect in young adolescent girls.
This study is a preliminary attempt to investigate whether internal or external pubertal changes and whether social or biological factors are more likely to be associated with negative affect. About 100 white girls aged 10-14 years were given a physical examination, had blood drawn, and filled out the Youth Behavior Profile and a life-events checklist. Negative affect increased during the most rapid rises in hormone levels; however, hormones accounted for only 4% of the variance in negative affect. Pubertal status and timing were not associated with negative affect. In contrast, social factors accounted for more variance than hormonal pubertal factors alone (8%-18%), as did the interaction of negative life events and pubertal factors (9%-15%). Results are discussed in terms of what hormonal activation effects are most likely to be found, the meaning of such effects for subsequent behavior, and the interaction of biological and social events.
Adolescent↗
Mood and behavior at adolescence: evidence for hormonal factors.
We studied the relationship among behavior, mood, pubertal development, hormonal levels, and psychological functioning in 100 adolescent white girls between the ages of 10.6-13.3 yr. The girls were grouped by pubertal breast stages and four stages of estradiol secretion. No significant mood or behavior changes were found as a function of pubertal stages, controlling for age effects, except for a decrease in interest in sports. The hormonal stages revealed a significant curvilinear trend for depressive affect (increase, then decrease; P less than 0.01), impulse control (decrease, then increase; P less than 0.04), and psychopathology (increase, then decrease; P less than 0.03) scales, indicating significant changes in these behaviors during times of rapid increases in hormone levels. These data suggest that hormonal changes may be more important than the physical changes as determinants of certain mood and behavior patterns at adolescence.
Adolescent↗
The auditory brainstem response in pediatrics.
When properly recorded and interpreted, the auditory brainstem response (ABR) serves as a powerful, noninvasive tool for the diagnosis of pediatric auditory disorders. The detection of eighth cranial nerve and brainstem dysfunction relies primarily on the comparison of wave latencies to normative data and between ears of the same patient. The description of peripheral hearing sensitivity thresholds by ABR relies primarily on the determination of the weakest stimulus intensity at which the ABR can be elicited. Differential diagnosis of sensorineural versus conductive loss is assisted by analysis of latency-intensity relationships and by bone-conducted ABR findings, whereas description of the frequency contour of the audiogram is possible using band-limited tone burst stimuli as well as other methods. From the caveats and case examples reported here, it should be clear that the ABR cannot be measured or interpreted from a patient in a "black box" fashion. Suprathreshold ABR recordings for neurotologic analysis are influenced by cochlear dysfunction, which can affect both absolute and interpeak wave latencies, and by conductive hearing loss, which affects absolute wave latencies, in such a way that the patient's audiogram must be known for proper test administration and interpretation. Interpretation of suprathreshold ABR data to infer hearing threshold sensitivity has extremely limited utility and can "clear" a child who indeed has substantial hearing loss. Threshold ABR recordings represent the most accurate means available to estimate the audiogram in the very young infant or difficult-to-test child, yet can be influenced by retrocochlear dysfunction, and require concurrent knowledge of outer and middle ear status as well as careful interpretive statements of the actual frequency range for which the audiogram has been estimated. The diagnosis of hearing impairment by ABR in a child is accomplished best when it is performed in the context of concurrent audiologic and otologic workups, with availability (on site or by referral) of a team of hearing health care professionals to evaluate and support the whole child and family. In the case of a newly diagnosed significant hearing impairment in an infant or toddler, input is needed from various professionals including those involved in education of the hearing-impaired, speech-language pathology, developmental psychology, social service, genetics, and ophthalmology, as well as the primary care pediatrician.(ABSTRACT TRUNCATED AT 400 WORDS)
Audiometry, Evoked Response↗
The psychological significance of secondary sexual characteristics in nine- to eleven-year-old girls.
82 9-11-year-old girls were seen in order to study the onset of puberty as represented by breast and pubic hair growth. Girls filled out self-report scales, mothers rated their daughters' breast and pubic hair development using schematic representations of the Tanner stages, and height was measured by a nurse practitioner. Breast growth, but not pubic hair growth, was expected to be associated with a positive body image, positive peer relationships, superior adjustment, and the rating of adult roles as important (marriage, children, and careers). These expectations were confirmed for all but the adult role measures. Controlling for pubic hair growth did not alter the findings for breast development. Associations with height also were examined. Height was linked to superior adjustment and career importance. These findings are discussed in terms of possible roles that different pubertal events may play in the self-definitions of young adolescents as well as the meaning of various physical changes to the girl and to others.
Body Height↗
The role of selectivity in the pathogenesis of eating problems in ballet dancers.
Forty-nine dancers from four national ballet companies in America (N = 32) and the People's Republic of China (N = 17) were surveyed (mean age, 24.6 +/- 4.18) from highly and moderately selective dance companies. The less selected American dancers reported significantly more eating problems (46% vs 11%; P less than 0.05), anorectic behaviors (2.77 vs 1.11; P less than 0.05), and familial obesity (42% vs 5%; P less than 0.05) than the Americans chosen from a company school. Differences were not found on these variables between the highly selected American and Chinese dancers. All of the groups reported a delay in menarche and weighed approximately 14% below their ideal weight for height. These data suggest that dancers who have survived a stringent process of early selection may be more naturally suited to the thin body image demanded by ballet and so less at risk for the development of eating problems. In addition, delayed menarche is typical of the majority of national dancers and probably is reflective of genetic and environmental factors.
Adolescent↗