Breast cancer among former college athletes compared to non-athletes: a 15-year follow-up.

A growing body of evidence indicates that physical activity is protective against breast cancer. In 1996-97, we conducted a 15-year follow-up of 5398 college alumnae comprised of former college athletes with their non-athletic classmates. Participants completed a detailed mailed questionnaire on their health history from 1981-82 to the present. Excluding women who had died and non-deliverable questionnaires, 84.7% (n = 3940) of the participants in our earlier study responded to the questionnaire; the response rate for former athletes was 86.6% (n = 1945), for non-athletes, 83.0% (n = 1995). Results confirmed our earlier findings. Based on self-reports, former college athletes had a significantly lower risk of breast cancer than the non-athletes. The OR for the 15-year incidence of breast cancer is 0.605 with 95% confidence interval (CI) (0.438-0.835); the 15-year incident breast cancers were 64 among the athletes and 111 among the non-athletes. Among women under 45 the protective effect of physical activity on the risk of breast cancer is considerably greater; odds ratio (OR) = 0.164, 95% CI (0.042-0.636). Athletic activity during the college and pre-college years is protective against breast cancer throughout the life span, and more markedly among women under 45. These results confirm our earlier findings and the findings of other investigators.

Association between endometriosis, dysplastic naevi and history of melanoma in women of reproductive age.

Women with melanoma and its precursor lesions, dysplastic naevi, have a higher prevalence of reproductive disorders than women without melanotic lesions. This association appears strongest among young women with dysplastic naevi and endometriosis. The purpose of this study was to evaluate patients with laparoscopy-confirmed endometriosis for the presence of dysplastic naevi. A total of 66 endometriosis patients and 35 controls completed a detailed questionnaire and underwent an extensive dermatological examination for the presence of dysplastic naevi. In all, 41% of patients aged < or = 32 years had dysplastic naevi, compared with 8% of controls (P = 0.038). In addition, 29% of patients with endometriosis reported a family history of melanoma compared with 10% of controls (P = 0.039). This study demonstrated an association between endometriosis and dysplastic naevi in younger women of reproductive age and found an associated family history of melanoma among endometriosis patients. These observations may be useful in the evaluation and care of young women by both gynaecologists and dermatologists.

Insulin response of women athletes in relation to body fat quantified by magnetic resonance imaging.

We report the glucose and insulin response to a 300-min glucose tolerance test among 17 women athletes as compared with 11 normal, nonatheletic controls. Also reported is the relationship of the insulin area under the curve as a function of percentages of total fat (TF), subcutaneous fat, and internal fat of total volume (TV) quantified by magnetic resonance imaging overall and at six regional sites. Athletes had a more sensitive insulin response to the glucose tolerance test as compared with controls. The insulin area under the curve of athletes and controls was significantly (p = 0.05) related to their overall TF/TV%; athletes had significantly less TF/TV% compared with the controls.

Carbonated beverages, dietary calcium, the dietary calcium/phosphorus ratio, and bone fractures in girls and boys.

PURPOSE: The aim of this study was to explore the association between carbonated beverage consumption, as well as other nutritional intake, and the occurrence of bone fractures in girls (mean +/- SD) 14.3 yr +/- 1.8 and boys 14.6 yr +/- 1.6. METHODS: Food-frequency questionnaires and medical histories were obtained from 76 girls and 51 boys. Subjects were recruited from a swimming club and physicians' offices; their physical characteristics are representative of the normal adolescent population. RESULTS: The data show a strong association between cola beverage consumption and bone fractures in girls [the adjusted odds ratio (OR) = 3.59; 95% confidence interval (CI) 1.21, 10.75; p = 0.022]. High intake of dietary calcium was protective (adjusted OR = 0.284; 95% CI 0.087, 0.920; p = 0.036). No association between the non-cola drinks and bone fractures was found. In boys, only total caloric intake was associated with the risk of bone fractures; the association was inverse. CONCLUSION: The high consumption of carbonated beverages and the declining consumption of milk are of great public health significance for girls and women because of their proneness to osteoporosis in later life.

Magnetic resonance imaging of overall and regional body fat, estrogen metabolism, and ovulation of athletes compared to controls.

The association of menstrual dysfunction of athletes with changes in body composition has been controversial, because most estimations of body fatness have been indirect. Using magnetic resonance imaging, we quantified the sc and internal fat over a specific volume from the fifth thoracic vertebra to femoral fat in the upper thigh and at 4 other anatomical landmarks of 17 athletes (13 oarswomen and 4 runners) compared to that in 11 nonathletic controls. The magnetic resonance imaging data were also analyzed for the athletes and controls in relation to ovulatory status, which was determined by assay of urinary pregnanediol glucuronide, and in relation to the extent of 2-hydroxylation of estradiol to a nonpotent metabolite, 2-hydroxyestrone, which was evaluated by radiometric analysis. We found that 1) the relative and absolute body fat values of the athletes were significantly less (P < 0.05) than those of the controls overall and at each of the six regional sites, although the body weights of the rowers were significantly heavier than those of the controls, and the runners did not differ from the controls; 2) the ratio of sc fat to internal fat was 80%:20% among both athletes and controls, even though the athletes had significantly less fat; 3) the extent of estradiol 2-hydroxylation was significantly (P = 0.005) inversely related to total fat as a percentage of the total volume and to sc fat as a percentage of the total volume (P = 0.004) overall and at each of the regional fat depots; 4) athletes with menstrual disorders had significantly decreased sc and internal fat overall and at all regional sites compared to controls; and 5) a subgroup of ovulatory rowers had an apparent increase or lack of decrease in internal fat at the level of vertebrae lumbar 4, sacral 1, and sacral 4, compared to controls, whereas their sc fat was decreased at these sites compared to that in controls. Changes in regional fat deposits of both sc and internal fat may be involved in the menstrual dysfunction of the athletes in addition to their decreased overall fatness. The body weight and body mass index of well trained athletes can be a misleading index of body composition.

Dysplastic nevi, cutaneous melanoma, and gynecologic disorders.

We compared the frequency of reproductive system diseases and disorders among 206 female patients with dysplastic nevi (DN), and/or melanoma, in comparison with random samples of women of comparable age without melanoma. The highest odds ratio (OR) for these age-related diseases and reproductive disorders occurs among the youngest age group of the patients with DN alone (mean age 35.1 +/- 1.2 yr): 44.2% of the DN subjects had one or more reproductive disorders compared with 19.8% of the random sample (OR 3.2, 95% CL (1.6, 6.5), P less than 0.001). The patients with melanoma and DN (mean age 41.5 +/- 1.4 yr) also had a significantly greater percentage of subjects with one or more reproductive disorders, though less so than the DN subjects: 49.4% compared to 33.7% (OR 1.9, 95% CL (1.1, 3.3), P = 0.02).

Magnetic resonance imaging of body fat of athletes compared with controls, and the oxidative metabolism of estradiol.

The extent of 2-hydroxylation of estradiol (E2), which yields a non-estrogenic metabolite (2-OHE1), increased significantly with decreasing subcutaneous fat (ScF)/total volume percent (TV%) and total fat (TF)/TV% evaluated by magnetic resonance imaging (MRI) for five athletes during low- and high-intensity training, and four controls. The increase in 2-hydroxylation with decreasing adiposity was associated with anovulation and amenorrhea among the athletes.

Body weight, body fat, and ovulation.

Women with moderate weight loss (10%-15% of ideal weight) have secondary or primary amenorrhea. Athletic women also may have amenorrhea, or anovulatory cycles, though body weight may be in the normal range, since muscles are heavy (80% water compared with 5%-10% water in adipose tissue). The amenorrhea, which is usually reversible with weight gain, decreased exercise, or both, is due to hypothalamic dysfunction; the pituitary-ovary axis is intact, suggesting that this type of amenorrhea is adaptive, preventing an unsuccessful pregnancy. Evidence is presented that the high percentage of body fat (26%-28%) in mature women is necessary for regular ovulatory cycles and may influence reproductive ability directly: (a) as an extragonadal source of estrogen by aromatization of androgen to estrogen, (b) by influencing the direction of estrogen metabolism to more potent or less potent forms, or (c) by changes in the binding properties of sex-hormone-binding globulin. Indirect signals may be abnormal control of temperature and changes in energy metabolism that accompany excessive leanness.

Overall body fat and regional fat distribution in young women: quantification with MR imaging.

Overall body fat and its distribution in different regions are important predispositions to known aberrations in lipid and glucose metabolism. The accuracy of MR imaging in estimating overall body fatness and regional fat distribution at individual landmarks was determined by comparing it with well-accepted measures by deuterium-oxide (D2O) dilution and bioimpedance analysis. Fourteen normal young women (athletes and control subjects) were studied. A total of 308 axial, T1-weighted, spin-echo MR images over a specific region in the trunk (21-24 scans per subject) were obtained. Morphometric computer image analysis was performed to determine the subcutaneous, internal, and total fat volumes in each image. The data were analyzed in two ways: data from all slices were summed to assess overall body fatness, and six anatomic landmarks were chosen for regional comparisons. MR-determined estimates of overall body fatness strongly correlated with total body fat measures by D2O dilution in both total fat (r = .91) and subcutaneous fat (r = .92) determinations. Athletes in both the low- and high-intensity training phases had significantly lower values of MR-determined total body fatness than did control subjects. Parallel to total body fatness, athletes had significantly lower MR-determined ratios of total fat/total volume in four of six individual landmarks compared with control subjects. Our experience suggests that MR is an accurate method to quantify overall body fatness, when compared with D2O dilution and bioimpedance analysis. MR could also discriminate regional components of subcutaneous and internal body fat at individual landmarks.

The right weight: body fat, menarche and ovulation.

Women with moderate weight loss (10-15% of ideal weight), as well as women with the severe weight loss of anorexia nervosa (30% of ideal weight), have secondary or primary amenorrhoea. A high proportion of well-trained dancers and athletes also have amenorrhoea, though weight may be in the normal range, since muscles are heavy (80% water, compared to 5-10% water in adipose tissue). The amenorrhoea is usually reversible with weight gain, decreased exercise or both. The amenorrhoea is due to hypothalamic dysfunction; the pituitary-ovary axis is intact, suggesting that this type of amenorrhoea is adaptive, preventing an unsuccessful pregnancy outcome. Evidence is presented that the high percentage of body fat (26-28%) in mature women is necessary for regular ovulatory cycles. Target weights for height are given for the evaluation and treatment of primary and secondary amenorrhoea due to weight loss. The high percentage of body fat in women may influence reproductive ability directly: (1) as an extragonadal source of oestrogen by aromatization of androgen to oestrogen; (2) by influencing the direction of oestrogen metabolism to more potent or less potent forms; or (3) by changes in the binding properties of sex-hormone-binding globulin. Indirect signals may be of abnormal control of temperature and changes in energy metabolism, which accompany excessive leanness.

Reproductive factors and melanoma of the skin among women.

A higher risk of reproductive system disorders, (which include benign tumors, endometriosis, dilation and curettage, hysterectomy, and other disorders requiring gynecologic biopsies) exist among women with cutaneous melanoma as compared to women with skin cancers: The odds ratio (OR) is 3.2, 95% confidence limits (1.0, 10.1), p = 0.049; as compared to a random sample of women with no melanoma or skin cancers, the OR is 3.9, 95% confidence limits (1.2, 12.4), p = 0.021. Confirming the observations of others, the authors found that melanoma was associated with red hair. The data also confirmed the finding that melanoma is associated with significantly fewer pregnancies. The mean numbers of pregnancies in the melanoma group is 1.83 +/- 1.6 (mean and standard deviation) compared to 2.99 +/- 1.9 in the skin cancer group and 2.93 +/- 1.9 in the random sample (p less than or equal to 0.05).