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Biomedical subjects

R E Frisch

Publications and source records attributed to R E Frisch.

At least 37 records · Page 2Linked to original sources
PubMed1989

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).

Analysis of Variance↗
PubMed1989

Estrogen 2-hydroxylase oxidation and menstrual function among elite oarswomen.

We monitored the estrogen metabolism and menstrual function of two groups of elite oarswomen as they progressed from a phase of low intensity training (phase I), to high intensity training (phase II), and back to low intensity training (phase III). Each phase lasted 3 months. The two groups of oarswomen included five oarswomen (group A) who experienced no menstrual dysfunction during the training year, even during the phase of high intensity training, and five oarswomen (group B) who experienced normal menses during phases of low intensity training but disrupted menses during the phase of high intensity training. Four nonathletic controls were also studied. Menstrual function was monitored throughout the training year by assay for pregnanediol glucuronide in overnight 12-h urine samples collected twice weekly. Repeated measures of the extent of estradiol metabolized by 2-hydroxylase oxidation, total body water, and nutrient intake of group A and B oarswomen were made at the three phases of the training year; the extent of estradiol metabolized by 2-hydroxylase oxidation was evaluated by radiometric analysis; total body water was measured by deuterium oxide dilution and bioimpedance analysis; and nutrient intake was evaluated by food frequency questionnaire. The group B oarswomen were found to metabolize a significantly greater fraction of administered [2-3H]estradiol by 2-hydroxylase oxidation than group A oarswomen (chi 2(1) = 6.57; P = 0.01). The extent of estradiol metabolized by 2-hydroxylase oxidation among group A oarswomen did not differ from that among nonathletic controls. The extent of 2-hydroxylase activity did not change significantly with the intensity of training among either group A or group B oarswomen. Oarswomen in groups A and B lost body weight and became leaner during the phase of high intensity training (phase II). Group A and B oarswomen did not differ in the degree of weight loss or in relative fatness during phase II. Over all subjects, the extent of estradiol metabolized by 2-hydroxylase oxidation was positively correlated with the extent of leanness. These data suggest that elevated estradiol 2-hydroxylase oxidation among elite oarswomen is associated with the occurrence of menstrual disturbances during phases of high intensity training and increased relative leanness.

Adult↗
PubMed1989

Lower prevalence of non-reproductive system cancers among female former college athletes.

Lower prevalence of non-reproductive system cancers among former college athletes. Med. Sci. Sports Exerc., Vol. 21, No. 3, pp. 250-253, 1989. The prevalence (lifetime occurrence) rates of cancers of nonreproductive organs and tissues were determined for 5,398 living alumnae, 2,622 of whom were former college athletes and 2,776 who had been nonathletes, from data on medical history, reproductive history, athletic training, and diet. The non-reproductive system cancers were divided into two classes: class I, which included cancers of the digestive system, thyroid, bladder, lung, and other sites and hematopoietic cancers (lymphoma, leukemia, myeloma, and Hodgkin's disease), and class II, which included skin cancers and cutaneous melanoma. The former college athletes had a significantly lower prevalence of class I cancers compared to the nonathletes; the age-adjusted relative risk (RR) equals 3.34, 95% confidence limits (1.35, 8.33), P = 0.009. In contrast, the prevalence rates of malignant melanomas and skin cancers did not differ significantly between the former athletes and nonathletes. The age-adjusted RR did not differ from 1.0. The lower prevalence rate of class I cancers among the former athletes is in accord with previous findings of a significantly lower prevalence rate of breast cancer and cancers of the reproductive system among former college athletes compared to nonathletes.

Adult↗
PubMed1987

Body fat, menarche, fitness and fertility.

Many well-trained athletes, ballet dancers and women who diet excessively have secondary or primary amenorrhoea. Less extensive training or weight loss may result in anovulatory menstrual cycles, or a shortened luteal phase. These disruptions of reproductive ability are due to hypothalamic dysfunction, which is correlated with weight loss or excessive leanness. It is proposed that these associations are causal and that the high percentage of body fat (26-28%) in the mature human female may influence reproduction directly. Four mechanisms are known: (i) adipose tissue converts androgens to oestrogen by aromatization. Body fat is thus a significant extragonadal source of oestrogen; (ii) body weight, hence fatness, influences the direction of oestrogen metabolism to more potent or less potent forms; leaner women make more catechol oestrogens, the less potent form; (iii) obese women and young, fat girls have a diminished capacity for oestrogen to bind sex-hormone-binding-globulin; (iv) adipose tissue can store steroid hormones. An indirect mechanism may be signals of abnormal control of temperature and changes in energy metabolism, which accompany excessive leanness. The hypothalamic reproductive dysfunction results in abnormal gonadotrophin secretion: there is an age inappropriate secretory pattern of luteinizing hormone (LH) and follicle stimulating hormone (FSH), resembling that of prepubertal children. The secretion of LH and the responses to LHRH are reduced in direct correlation with the amount of weight loss. Other evidence from non-athletic and athletic women and mammals is presented in support of the hypothesis that a particular, minimum ratio of fat to lean mass is normally necessary for menarche (approximately 17% fat/body wt) and the maintenance of female reproductive ability (approximately 22% fat/body wt). Nomograms are given for the prediction of these critical weights for height from a fatness index; these weights are useful clinically in the evaluation of nutritional amenorrhoea and the restoration of fertility in underweight women. Evidence is presented that undernutrition and hard physical work can affect the natural fertility of populations, by the delay of menarche, a longer period of adolescent subfecundity, a longer birth interval and an earlier age of menopause. Data from a study of the long-term reproductive health of 2622 former college athletes compared with 2766 non-athletes show that the former college athletes had a significantly lower lifetime occurrence of breast cancer and cancers of the reproductive system, and a lower lifetime occurrence of benign tumours of these tissues, compared with the non-athletes.(ABSTRACT TRUNCATED AT 400 WORDS)

Adipose Tissue↗
PubMed1987

Bone fractures among former college athletes compared with nonathletes in the menopausal and postmenopausal years.

Data are presented on the prevalence (lifetime occurrence) of bone fractures among 5398 college alumnae, 2622 former college athletes, and 2776 nonathletes, ranging in age from 21 to 80 years. As expected from increased physical activity, the former college athletes in each age decade from 20 to 70 years and over reported a higher lifetime occurrence (i.e., at any age up to the time of reporting) of bone fractures of all types, than that of nonathletes (40.5 versus 31.9%, P less than .001). However, when athletic activity was accounted for, the former college athletes were at no greater risk of fractures in the menopausal years than were nonathletes. Among women 60 years and over who were fracture-free up to age 40, the rate for any fracture at age 40 or over was 29% for former college athletes compared with 32% for nonathletes, a nonsignificant difference.

Adult↗
PubMed1986

Lower prevalence of diabetes in female former college athletes compared with nonathletes.

The prevalence rate of diabetes was determined for 5398 living college alumnae (2622 former college athletes and 2776 nonathletes) from data on medical history, athletic training, and diet. For all ages, the prevalence rate among the former athletes was 0.57% (15/2622) and among the nonathletes was 1.3% (37/2776). The former college athletes and the nonathletes had similar percentages in family history of diabetes, i.e., 12.0 and 13.5%, respectively. For cases occurring at age greater than or equal to 20 yr (thus assessing the effects of college athletic training), 0.5% (13/2622) of the former college athletes had diabetes compared to 1.2% (32/2776) of the nonathletes; the relative risk is 2.24 [95% confidence limits (CL), 1.19 and 4.74, respectively]. Omitting cases of gestational diabetes, the relative risk of diabetes in nonathletes versus athletes is 3.41 (95% CL, 1.33 and 8.70). The percentages of former athletes and nonathletes that are insulin-using, non-insulin-using, and gestational diabetics did not differ significantly. The athletes were leaner than the nonathletes at all ages up to 70 yr. Of the former college athletes, 82% had been on precollege teams, compared to 25% of the college nonathletes; 74% of the former athletes were exercising regularly, compared to 57% of the nonathletes. We conclude that long-term athletic training is associated with a lower risk of the development of diabetes.

Adult↗
PubMed1985

Lower prevalence of breast cancer and cancers of the reproductive system among former college athletes compared to non-athletes.

The prevalence (lifetime occurrence) rate of cancers of the reproductive system (uterus, ovary, cervix and vagina) and breast cancer was determined for 5,398 living alumnae, 2,622 of whom were former college athletes and 2,776 non-athletes, from data on medical and reproductive history, athletic training and diet. The former athletes had a significantly lower risk of cancer of the breast and reproductive system than did the non-athletes. The relative risk (RR), non-athletes/athletes, for cancers of the reproductive system was 2.53. 95% confidence limits (CL) (1.17, 5.47). The RR for breast cancer was 1.86, 95% CL (1.00, 3.47). The analysis controlled for potential confounding factors including age, family history of cancer, age of menarche, number of pregnancies, use of oral contraceptives, use of oestrogen in the menopausal period, smoking, and leanness. Of the college athletes, 82.4% had been on pre-college teams compared to 24.9% of the college non-athletes. We conclude that long term athletic training may lower the risk of breast cancer and cancers of the reproductive system.

Adult↗
PubMed1984

Metabolic, endocrine, and reproductive changes of a woman channel swimmer.

We report the coordinated metabolic, hormonal, and reproductive data of a female channel swimmer during the pre-swim training period, immediately post-swim, and in the post-swim untrained state. Urine and blood samples collected at these times were assayed for diurnal urinary catecholamines, urinary C-peptide and 3-methylhistidine, total blood ketone bodies, glycerol, the reproductive hormones, adrenal androgens, and thyroid hormones. Subcutaneous fat was measured by ultrasonography. All of the metabolic and hormonal data post-swim except cortisol reflected the severe physiological stress. Urinary catecholamines returned to near-normal levels by 12 hours post-swim. The metabolic changes were associated with reproductive changes, including a shortened luteal phase, absence of ovulation, and increased LH secretion relative to FSH. The swimmer maintained high levels of body fat; she did not become amenorrheic. Metabolic and reproductive hormone levels returned to normal by 2 months post-swim.

Adipose Tissue↗