Bleeding patterns during the menopausal transition in the multi-ethnic Study of Women's Health Across the Nation (SWAN): a prospective cohort study

OBJECTIVE

Previous studies describing menses duration and heaviness of flow during the menopausal transition (MT) have been short in duration and limited to white women. We estimated the frequency of and risk factors for prolonged bleeding, spotting and heavy bleeding during the MT in an ethnically diverse population.

DESIGN

Prospective community-based cohort study.

SETTING USA

southeastern Michigan, northern California and Los Angeles, California.

POPULATION

A total of 1320 midlife women who participated in the Study of Women's Health Across the Nation (SWAN) Menstrual Calendar Substudy. Participants included African-American, white, Chinese, and Japanese women.

METHODS

Women completed daily menstrual calendars from 1996 to 2006, and provided information on hormone therapy, smoking and physical activity. Annual measures included height and weight. Kaplan-Meier survival analysis and multivariable regression were used to analyse the data.

MAIN OUTCOME MEASURES

Menses of 10+ days, spotting of 6+ days, heavy bleeding of 3+ days.

RESULTS

At least three occurrences of menses 10+ days was reported by 77.7% (95% confidence interval [95% CI] 56.7-93.2), of 6+ days of spotting by 66.8% (95% CI 55.2-78.0) and of 3+ days of heavy bleeding by 34.5% (95% CI 30.2-39.2) of women. Menses of 10+ days, 6+ days of spotting, and 3+ days of heavy bleeding were associated with MT stage, uterine fibroids, hormone use and ethnicity. Body mass index was associated with 3+ days of heavy bleeding.

CONCLUSIONS

These data provide clinicians and women with important information about the expected frequency of prolonged and heavy bleeding and spotting during the menopausal transition that may facilitate clinical decision making.

Indoor carbon monoxide and PM2.5 concentrations by cooking fuels in Pakistan

In developing countries biomass combustion is a frequently used source of domestic energy and may cause indoor air pollution. Carbon monoxide (CO)and particulate matter with an aerodynamic diameter of 2.5 lm or less (PM2.5)were measured in kitchens using wood or natural gas (NG) in a semi-rural community in Pakistan. Daytime CO and PM2.5 levels were measured for eight continuous hours in 51 wood and 44 NG users from December 2005 to April 2006. The laser photometer PM2.5 (Dustrak, TSI) was calibrated for field conditions and PM2.5 measurements were reduced by a factor of 2.77. CO was measured by an electrochemical monitor (Model T15v, Langan). The arithmetic mean for daytime CO concentration was 29.4 ppm in wood users; significantly higher than 7.5 ppm in NG users (P < 0.001). The arithmetic mean for daytime PM2.5 concentrations was 2.74 mg/m3 in wood users; significantly higher than 0.38 mg/m3 in NG users (P < 0.001). Higher peak levels of CO and PM2.5 were also observed in wood users. Time spent in the kitchen during fuel burning was significantly related to increasing CO and PM2.5 concentrations in wood users.These findings suggest that cooking with wood fuel may lead to hazardous concentrations of CO and PM2.5.

PRACTICAL IMPLICATIONS

Biomass combustion is frequently used in developing countries for cooking. This study showed very high level of air pollution in kitchens using wood as the cooking fuel. Many people, especially women and children, are vulnerable to exposure to very high levels of air pollutants as they spend time in the kitchen during cooking hours.

Factors related to declining luteal function in women during the menopausal transition

CONTEXT

Reproductive hormones are incompletely characterized during the menopause transition (MT).

HYPOTHESIS

Increased anovulation and decreased progesterone accompany progress through the MT.

DESIGN

The Daily Hormone Study (DHS) of the Study of Women's Health Across the Nation (SWAN) included 848 women aged 43-53 yr at baseline who collected daily urine for one cycle or up to 50 d annually for 3 yr.

MAIN OUTCOME MEASURES

LH, FSH, estrone conjugates, and pregnanediol glucuronide levels were assessed. Cycles were classified by presumed luteal (ovulatory) status and bleeding. Hormones were related to time in study, age, menopausal status, and selected variables.

RESULTS

Ovulatory-appearing cycles declined from 80.9% at baseline to 64.7% by the third assessment (H3). Cycles presumed anovulatory and not ending with bleeding by 50 d (anovulatory/nonbleeding) increased from 8.4 to 24% by H3 and were associated with progress to early perimenopause [odds ratio (OR) = 2.66; confidence interval (CI) = 1.17-6.04] or late perimenopause (OR = 56.21; CI = 18.79-168.12; P < 0.0001), African-American ethnicity (OR = 1.91; CI = 1.06-3.43), and less than high school education (OR = 3.51; CI = 1.62-7.62). Anovulatory cycles ending with bleeding remained at about 10% from baseline to H3; compared with ovulatory cycles, they were associated with obesity (OR = 4.68; CI = 1.33-16.52) and more than high school education (OR = 2.12; CI = 1.22-3.69; P = 0.02). Serum estradiol in both the highest and lowest categories was associated with anovulatory/nonbleeding collections. Pregnanediol glucuronide decreased 6.6% for each year on study. Insulin sensitivity measures did not relate strongly to menstrual cycle hormones.

CONCLUSIONS

Anovulation without bleeding represents progression of the MT. A small but detectable decrease in luteal progesterone excretion occurs as women progress through the MT.

Assessing menstrual cycles with urinary hormone assays

The Study of Women's Health Across the Nation (SWAN) is a multiethnic cohort study of middle-aged women enrolled at seven US sites. A subset of 848 women completed a substudy in which their urinary gonadotropins and sex steroid metabolites were assessed during one complete menstrual cycle or up to 50 consecutive days. Urine was analyzed for LH, FSH, estrone conjugates (E1c), and pregnanediol glucuronide (Pdg). To prepare for serial analysis of this large, longitudinal database in a population of reproductively aging women, we examined the performance of algorithms designed to identify features of the normal menstrual cycle in midreproductive life. Algorithms were based on existing methods and were compared with a "gold standard" of ratings of trained observers on a subset of 396 cycles from the first collection of Daily Hormone Substudy samples. In evaluating luteal status, overall agreement between and within raters was high. Only 17 of the 396 cycles evaluated were considered indeterminate. Of the 328 cycles rated as containing evidence of luteal activity (ELA), 320 were considered ELA by use of a Pdg threshold detection algorithm. Of 51 cycles that were rated as no evidence of luteal activity, only 2 were identified by this algorithm as ELA. Evaluation of the day of the luteal transition with methods that detected a change in the ratio of E1c to Pdg provided 85-92% agreement for day of the luteal transition within 3 days of the raters. Adding further conditions to the algorithm increased agreement only slightly, by 1-8%. We conclude that reliable, robust, and relatively simple objective methods of evaluation of the probability and timing of ovulation can be used with urinary hormonal assays in early perimenopausal women.

Premature menopause in a multi-ethnic population study of the menopause transition

BACKGROUND

Premature menopause, also termed premature ovarian failure (POF), is characterized by cessation of menstruation before the age of 40 years. Little information is available on the general prevalence of POF or on the prevalence by ethnic group. There is also a lack of information on the association of POF with health indicators.

METHODS

A cross-sectional survey of women aged 40-55 years was conducted at seven sites in the USA to determine eligibility for a community-based, multi-ethnic longitudinal study of the peri-menopause (The Study of Women Across the Nation, SWAN). Interview data were used to (i). determine the prevalence of self-reported POF overall and by ethnic group, and (ii). assess the association of POF with selected self-reported variables related to health. Cases of POF included only women with no discernible cause for POF.

RESULTS

POF was reported by 1.1% (126/11 652) of women. By ethnicity, 1.0% (95% CI, 0.7-1.4) of Caucasian, 1.4% (95% CI, 1.0-2.1) of African American, 1.4% (95% CI, 0.8-2.5) of Hispanic, 0.5% (95% CI, 0.1-1.9) of Chinese and 0.1% (95% CI, 0.02-1.1) of Japanese women experienced POF. The differences in frequency across ethnic groups were statistically significant (P = 0.01). Only Caucasian, African American and Hispanic women were included in further analyses since too few Asian women had POF. In a multivariate model, POF was independently associated with osteoporosis, female hormone use (excluding oral contraceptives), higher body mass index (BMI) and current smoking after adjustment for education level, ability to pay for basics, site and age at interview. In Caucasian women, use of female hormones, osteoporosis, severe disability and smoking were significantly associated with POF. In contrast, POF in African American women was associated with higher BMI and female hormone use, but not osteoporosis.

CONCLUSIONS

The prevalence of POF appears to vary by ethnicity. Health factors associated with POF also vary by ethnicity but because of the cross-sectional study design, it is not possible to determine cause and effect relationships. Health risks of POF would benefit from further study.

Factors associated with age at natural menopause in a multiethnic sample of midlife women

An unprecedented number of women will experience menopause in the next decade. Although the timing of menopause affects long-term disease risk, little is known about factors that affect this timing. In the present 1995--1997 cross-sectional study, the Study of Women's Health Across the Nation, the relation of demographic and lifestyle factors to age at natural menopause was examined in seven US centers and five racial/ethnic groups. All characteristics were self-reported by women aged 40--55 years (n = 14,620). Cox proportional hazards models were used to estimate the probability of menopause by age. Overall, median age at natural menopause was 51.4 years, after adjustment for smoking, education, marital status, history of heart disease, parity, race/ethnicity, employment, and prior use of oral contraceptives. Current smoking, lower educational attainment, being separated/widowed/divorced, nonemployment, and history of heart disease were all independently associated with earlier natural menopause, while parity, prior use of oral contraceptives, and Japanese race/ethnicity were associated with later age at natural menopause. This sample is one of the largest and most diverse ever studied, and comprehensive statistical methods were used to assess factors associated with age at natural menopause. Thus, this study provides important insights into this determinant of long-term disease risk in women.

Risk factors for primary biliary cirrhosis in a cohort of patients from the united states

Although the etiology of primary biliary cirrhosis (PBC) remains unknown, environmental factors may act to trigger the disease in genetically susceptible hosts. To assess specific risk factors, we conducted a survey using standardized NHANES questions to 241 PBC patients in the United States, 261 of their siblings, and 141 friends without PBC. The overall response rate was 199 of 241 (83%) among PBC cases, 171 of 261 (67%) among siblings, and 141 of 225 (62. 7%) among friend controls. The female-to-male ratio among cases in this sample was approximately 10:1; the mean age was 53 years, and 97% were Caucasian. Other autoimmune diseases reported most frequently by PBC cases included Sjogren's syndrome (17.4%) and Raynaud's syndrome (12.5%). Approximately 6% of cases reported at least one family member with PBC. Adjusted odds ratios (OR) were elevated for cases compared with friends for other autoimmune diseases (OR = 4.92, 95% confidence interval [CI] = 2.38, 10.18), smoking (OR = 2.04, 95% CI = 1.10, 3.78), tonsillectomy (OR = 1.86, 95% CI = 1.02, 3.39), and vaginal or urinary tract infection (UTI) in females only (OR = 2.12, 95% CI = 1.10, 4.07). Similarly elevated ORs were observed for these risk factors when cases were compared with their siblings. The higher rate of UTI among cases is particularly interesting in light of previous data, and raises the possibility of an infectious etiology for PBC and of molecular mimicry as an etiologic mechanism. The significance of smoking in the multivariate models supports the findings of previous studies and raises the issue of the influence of smoking on a Th1 response.

Relation of demographic and lifestyle factors to symptoms in a multi-racial/ethnic population of women 40-55 years of age

A community-based survey was conducted during 1995-1997 of factors related to menopausal and other symptoms in a multi-racial/ethnic sample of 16,065 women aged 40-55 years. Each of seven sites comprising the Study of Women's Health across the Nation (SWAN) surveyed one of four minority populations and a Caucasian population. The largest adjusted prevalence odds ratios for all symptoms, particularly hot flashes or night sweats (odds ratios = 2.06-4.32), were for women who were peri- or postmenopausal. Most symptoms were reported least frequently by Japanese and Chinese (odds ratios = 0.47-0.67 compared with Caucasian) women. African-American women reported vasomotor symptoms and vaginal dryness more (odds ratios = 1.17-1.63) but urine leakage and difficulty sleeping less (odds ratios = 0.64-0.72) than Caucasians. Hispanic women reported urine leakage, vaginal dryness, heart pounding, and forgetfulness more (odds ratios = 1.22-1.85). Hot flashes or night sweats, urine leakage, and stiffness or soreness were associated with a high body mass index (odds ratios = 1.15-2.18 for women with a body mass index > or =27 vs. 19-26.9 kg/m2). Most symptoms were reported most frequently among women who had difficulty paying for basics (odds ratios = 1.15-2.05), who smoked (odds ratios = 1.21-1.78), and who rated themselves less physically active than other women their age (odds ratios = 1.24-2.33). These results suggest that lifestyle, menstrual status, race/ethnicity, and socioeconomic status affect symptoms in this age group.

The use of complementary/alternative medicine for the treatment of asthma in the United States

Despite our advances in the diagnosis and treatment of asthma, the incidence of mortality is increasing in developed countries. As patients and health care providers seek new options for the treatment and prevention of asthma, various complementary and alternative medical therapies are being used. With funding from the Office of Alternative Medicine, National Institutes of Health, our goal was to identify the type and prevalence of complementary and alternative treatments for asthma in use in the United States in order to establish a research agenda for the study of the most promising therapies. A survey was developed by an expert panel. After undergoing a preliminary round of testing and improvement, the survey was then sent along with a postage-paid return envelope as inserts in the May 1996 issue of Alternative Therapies in Health and Medicine, a peer-reviewed periodical of complementary and alternative medical research and scholarly activity; 10,000 surveys were distributed. We asked that only those who treated asthma respond. The surveys were designed to identify characteristics of the respondent, their particular practice type, use of complementary and alternative medicine, or conventional medicine in general, patient characteristics and numbers, and their use of 20 specific potential therapies to treat asthma. A total of 564 surveys were returned. The 5.64% response rate was low but was reflective of the demographics of the readership of this journal of complementary and alternative medicine. The survey population was 46% male and 43% female; 11% did not specify gender. They ranged in age from under 31 years old to over 70. The largest group (37%) of respondents held degrees as medical doctors, 27% held doctorates in complementary and alternative medicine related disciplines, 11% had registered nursing degrees, 4% were acupuncturists and 18% did not specify their training. Practice characteristics between MD and non-MD asthma care providers did not differ. The majority had general practices (75%) seeing all ages of patients. MDs were less likely to employ complementary and alternative medicine techniques for asthma compared to non-MDs. Both groups identified dietary and nutritional approaches as their most prevalent and useful asthma treatment option. Use of botanicals, meditation and homeopathy were frequently cited; statistically significant differences appeared in the rankings of treatment usefulness and prevalence between MD and non-MDs. Non-MD asthma care providers were more likely to ask patients about their use of complementary and alternative treatments for asthma than MDs (92% vs. 70%), while both groups showed statistically significant increases in their levels of patient inquiries compared to 2 years previously (up 9% and 8% for MDs and non-MDs respectively). The predominance of diet and nutrition supplementation used by MDs and non-MDs suggests that further attention and research efforts should be directed toward this area of complementary and alternative practice. Other complementary and alternative medicine practices such as botanicals, meditation and homeopathy appear to warrant research efforts. Differences between MDs and non-MDs in their use of such therapies may reflect different philosophies as well as training.

Epidemiology of and risk factors for pancreatic cancer

In the United States, incidence of and mortality from pancreatic cancer increased for several decades earlier in this century but have tended to level off in recent years. Rates increase with age and are higher in blacks than in whites and higher in men than in women. Cigarette smoking increases the risk of pancreatic cancer, while alcohol consumption largely shows no relationship, coffee consumption shows little, if any, association, and a number of occupational exposures seem to be associated but the results are not fully consistent. Finally, human studies have suggested positive associations with meat consumption and carbohydrate intake and a protective effect of dietary fiber and consumption of fruits and vegetables. Thus, much progress has been made in the last two decades in identifying risk factors, but much epidemiologic work is needed to identify and reduce putative exposures.

Risk factors for systemic illnesses following agricultural exposures to restricted organophosphates in California, 1984-1988

Organophosphate (OP)-related systemic illnesses reported to the Worker Health and Safety (WH&S) Branch, and restricted OP-related agricultural use data reported to the Information Services Branch at the California Department of Food and Agriculture (CDFA) (now CAL-EPA) during 1984-1988 were used to assess factors associated with OP-related systemic illnesses. Counts of OP-related systemic illnesses (numerator), relative to OP-related use data (denominator), such as pounds applied, number of applications, and acres treated (pounds applied/acres treated), were analyzed by crop treated, season of application, method of application, geographic region, and by specific OP applied. A Relative Illness/Use Ratio (RIUR) was calculated by Poisson regression. The highest risk of systemic illness was associated with OP applications to fleshy fruit (mainly fruit trees) compared to all other crops combined (RIUR = 2.9, 95%CI = 2.2-3.9) using pounds applied in the denominator, followed by vegetables and melons (RIUR = 1.9, 95%CI = 1.4-2.4). Air applications resulted in higher RIURs for systemic illness than did ground applications (RIUR = 2.1, 95%CI = 1.7-2.5). Specific OPs that showed significantly elevated RIURs for systemic illness when compared to other OPs were Mevinphos (RIUR = 5.8, 95%CI = 5.0-6.8), Demeton (RIUR = 4.3, 95%CI = 2.6-7.1), Oxydemeton-Methyl (RIUR = 3.8, 95%CI = 3.0-4.9), Methamidophos (RIUR = 1.6, 95%CI = 1.2-2.0) and Azinphos-Methyl (RIUR = 1.3, 95% CI = 1.1-1.6).

Case-control studies and their application to endocrinology

The steps for undertaking the case-control approach to studying potential causal factors (i.e., host or environmental factors) related to diseases or conditions of interest are outlined, together with warnings of the potential pitfalls and biases to be avoided. Guidelines are provided for appropriate selection of cases and controls and for ascertaining and valid exposure or host information. In addition, the elements needed to determine the sample size needed for a case-control study, the approach to the analysis of case-control data, and criteria for assessing whether associations observed in epidemiologic studies are actually causal also are provided. Finally, the strengths and limitations of the case-control approach, compared with the cohort approach, are described. Published studies are cited to provide endocrinologic examples of the methodologies and issues raised by the case-control study approach.

Identification of anovulation and transient luteal function using a urinary pregnanediol-3-glucuronide ratio algorithm

The sensitivity and specificity of a urinary pregnanediol-3-glucuronide (PdG) ratio algorithm to identify anovulatory cycles was studied prospectively in two independent populations of women. Urinary hormone data from the first group was used to develop the algorithm, and data from the second group was used for its validation. PdG ratios were calculated by a cycles method in which daily PdG concentrations indexed by creatinine (CR) from cycle day 11 onward were divided by a baseline PdG (average PdG/Cr concentration for cycle days 6-10). In the interval method, daily PdG/CR concentrations from day 1 onward were divided by baseline PdG (lowest 5-day average of PdG/CR values throughout the collection period). Evaluation of the first study population (n = 6) resulted in cycles with PdG ratios > or = 3 for > or = 3 consecutive days being classified as ovulatory; otherwise they were anovulatory. The sensitivity and specificity of the PdG ratio algorithm to identify anovulatory cycles in the second population were 75% and 89.5%, respectively, for all cycles (n = 88); 50% and 88.3% for first cycles (n = 40) using the cycles method; 75% and 92.2%, respectively, for all cycles (n = 89); and 50% and 94.1% for first cycles (n = 40) using the interval method. The "gold standard" for anovulation was weekly serum samples < or = 2 ng/ml progesterone. The sensitivity values for all cycles and for the first cycle using both methods were underestimated because of apparent misclassification of cycles using serum progesterone due to infrequent blood collection. Blood collection more than once a week would have greatly improved the sensitivity and modestly improved the specificity of the algorithm. The PdG ratio algorithm provides an efficient approach for screening urine samples collected in epidemiologic studies of reproductive health in women.

Epidemiologic methods for prospective assessment of menstrual cycle and reproductive characteristics in female semiconductor workers

Methods were developed to assess potential adverse effects of semiconductor fabrication work in a prospective study of reproductive health. All women aged 18-44 years who worked in seven silicon-wafer fabrication sites in five companies and a frequency-matched sample of women in nonfabrication jobs were included. Among 3,480 selected for screening, 2,639 (75%) completed a self-administered questionnaire to identify women at risk of pregnancy. Among the 739 (28%) eligible women, 481 (65%) completed baseline interviews and 402 (83.6%) completed at least one menstrual cycle of follow-up by providing daily diaries and daily urine samples. Menstrual cycle characteristics were assessed from questionnaires and diaries. Urine samples were assayed for reproductive hormones to identify conceptions. The usual cycle length recalled at baseline was 28 days. The mean cycle length (MCL) recorded in diaries was 29 days, with greater dispersion than at baseline. The median of the MCL from diary data was 28 days for women reporting regular cycles at baseline but 34 days for women reporting irregular cycles at baseline, and the median standard deviation in cycle length per woman was 2.5 days and 7.5 days, respectively. The prospective method, while expensive and labor intensive, showed good compliance. Nevertheless, recall also provided reasonably accurate estimates and distinguished women with regular and irregular cycles.

Association of spontaneous abortion and other reproductive effects with work in the semiconductor industry

This study tested the hypothesis that fabrication room (fab) work in the silicon-based semiconductor industry is associated with an increased risk of spontaneous abortion (SAB). The study was conducted nationwide at 14 companies representing a spectrum of large to small manufacturers. A small increase in risk of SAB was observed among fab workers compared with nonfabrication room (nonfab) workers in two cohorts, historical (adjusted RR = 1.43, 95% confidence interval [CI] 0.95-2.09) and prospective (adjusted RR = 1.25, 95% CI = 0.63-1.76). Analysis of specific fab exposures in the historical cohort showed a consistent, dose-response association of SAB with photoresist and developer solvents, whose major component was ethylene-based glycol ethers. The consistency of our findings and the toxicological data for these agents suggest that this is a causal association. Independent associations of SAB with self-reported stress and with etching fluorides were observed and require further research. No significant decrease in fertility was observed among men or women working in fabs, but reduced fecundability was suggested for some women fab workers.

Communication issues in a multicomponent study of semiconductor employees

A variety of methods were used to address communication problems in the Semiconductor Health Study (SHS). The diverse employee population required investigators to consider language, ethnic, and cultural differences in planning and implementing the study design. Studies of reproductive health in the workplace raise special concerns, including the critical need to preserve confidentiality and privacy of subjects. Notification of results of epidemiological studies reporting workplace hazards requires sensitivity to needs of workers. SHS investigators directly communicated overall results of this multicomponent study to participating employees at all sites and notified subjects of results of individual industrial hygiene monitoring and endocrine hormone assays.

Prospective monitoring of early fetal loss and clinical spontaneous abortion among female semiconductor workers

Women who work in silicon wafer fabrication rooms (fabs) have been reported to have an increased risk of spontaneous abortion (SAB). Although previous studies have included only clinically recognized SABs, more than two-thirds of SABs may be clinically unrecognized. To determine whether fab work is associated with SAB, we recruited 152 fab and 251 nonfab workers, who collected urine samples for a 6-month period. Samples were analyzed by immunoradiometric assay for the presence of human chorionic gonadotropin to detect early fetal losses. Approximately 63% of fab and 46% of nonfab pregnancies ended in SAB [adjusted relative risk (RR) = 1.25; 95% confidence interval (CI) = 0.63-1.76]. Similar RR were seen for women who worked in dopant and thin-film processes (adjusted RR = 1.30; 95% CI = 0.51-1.96) or in masking (adjusted RR = 1.30; 95% CI = 0.59-1.84). The four pregnancies among women who worked with ethylene-based glycol ethers ended in SAB.

Prospectively assessed menstrual cycle characteristics in female wafer-fabrication and nonfabrication semiconductor employees

Women aged 18-44 years in silicon-wafer fabrication-room (fab) jobs and frequency-matched women in nonfab jobs were screened for a prospective study of reproductive health (n = 2,639). Among the 739 (28%) eligible women, 481 (65%) completed a baseline interview; 402 completed at least one menstrual cycle of follow-up with daily diaries and urinary assays to exclude conceptive cycles. Adjusted mean cycle lengths (MCL) did not differ between fab and nonfab women (p = 0.97). Women working in thin film and ion implantation (TFII) had the highest adjusted MCL (34.8 +/- 1.7 days) compared with nonfab workers (32.5 +/- 1.4 days, p = 0.07). Among women working exclusively in one group, TFII women had significantly higher MCL (36.1 +/- 2.04 days) than nonfab women (32.0 +/- 1.38 days, p = 0.017). TFII women were also more likely to have all cycles > 35 days (adjusted relative risk [RR] = 2.45; 95% CI = 0.85-6.06). Variability was assessed by logarithmic transformation of the mean standard deviation (MLSD) in cycle length per woman and adjusted for age and ethnicity (4.5 days for fab vs. 4.0 days for nonfab, p = 0.16). Women working exclusively in TFII or photolithography (PHOTO) had significantly higher adjusted MLSD in cycle length (6.68 +/- 1.28 and 5.72 +/- 1.24 days, respectively) than women in nonfab (4.1 +/- 1.16 days, p = 0.013 and 0.019, respectively). Fab and nonfab women did not differ significantly in mean days of bleeding or risk of having cycles > 35 or < 24 days. However, elevated risks of having cycles < 24 days were seen in supervisor engineers (adjusted RR = 2.46, 95% CI = 1.19-3.63) and PHOTO women (adjusted RR = 1.83, 95% CI = 0.94-2.88).

Laboratory methods for evaluating early pregnancy loss in an industry-based population

Laboratory methods were adapted or developed to analyze approximately 70,000 daily urine samples collected during more than 2,500 menstrual cycles from 448 women working in the semiconductor industry. An immunoenzymometric assay (IEMA) for human chorionic gonadotropin (hCG) was employed for screening cycles in order to optimize laboratory resources and to reduce the number of samples requiring analysis by less efficient methods. The presence of hCG in urine was confirmed by the definitive immunoradiometric assay (IRMA). The screening assay eliminated 78% of cycles from further analysis because there was no evidence of conception. Thirty-eight of 448 cycles identified as having significant levels of hCG with the IEMA were confirmed as hCG positive with the IRMA. HCG-positive cycles were further evaluated by examination of daily diary data and by laboratory assays for ovarian and pituitary hormones. As a result of these evaluations, 17 of the 38 cycles identified by the IRMA as positive for hCG were found to be nonconceptive cycles. These results demonstrate the effectiveness of screening assays for hCG, as well as the importance of using multiple urinary biomarkers for the detection of early fetal loss with daily urine samples.

Prospective assessment of fecundability of female semiconductor workers

To investigate a possible effect of reduced fecundability (probability of conception per menstrual cycle) among women who fabricate silicon wafers, 152 fabrication-room (fab) and 251 nonfab workers were followed for an average of five menstrual cycles. Daily urine samples were analyzed to confirm clinical spontaneous abortions (SABs) and early fetal losses (EFLs). Adjusted fecundability odds ratios (FRs) for fab workers ranged from 0.59 to 0.72 (p = 0.09-0.28 vs. nonfab). For clinical pregnancies only, the adjusted FR ranged from 0.43-0.50 (p = 0.04-0.09 vs. nonfab). This lower fecundability was most pronounced among dopants and thin-film workers [adjusted FR = 0.61, 95% confidence interval (CI) = 0.27-1.40 for all pregnancies; adjusted FR = 0.22, 95% CI = 0.05-0.96 for clinical pregnancies] and in workers exposed to ethylene-based glycol ethers (adjusted FR = 0.37, 95% CI = 0.11-1.19).

Epidemiology of and risk factors for pancreatic cancer

In the United States, incidence of and mortality from pancreatic cancer increased for several decades earlier in this century but have tended to level off in recent years. Rates increase with age and are higher in blacks than in whites and higher in males than in females. No consistent differences by socioeconomic status or by geographic location in the United States have been identified, although international variation and differences in migrants have been observed. Thus, both genetic and environmental factors may be playing significant roles in the development of pancreatic cancer. Cigarette smoking increases the risk of pancreatic cancer, but the strength of this association is much less than for lung cancer or other smoking-related cancers. Epidemiologic studies of the effect of alcohol consumption on pancreatic cancer largely show no relationship, and the results for coffee consumption indicate little, if any, association. Human studies have suggested positive associations with meat consumption and carbohydrate intake and a protective effect of dietary fiber and consumption of fruits and vegetables. Results of a number of occupational studies are suggestive of increased risk associated with some exposures but are not fully consistent. Thus, much progress has been made in the last two decades in identifying risk factors, but much epidemiologic work is needed to identify and reduce putative exposures.

Determinants of disability in illnesses related to agricultural use of organophosphates (OPs) in California

Organophosphate (OP)-related illness data reported to the Worker Health and Safety Branch (WH&S) at the California Department of Food and Agriculture (CDFA, now Cal-EPA) in the years 1984-1988 were examined. Eight hundred and seventy-eight cases with systemic illness and 199 cases of skin disease or eye injury were identified. Systemic cases were divided into two outcome groups: (1) "severe," disability and/or hospitalization days (n = 361), and (2) "mild," no disability or hospitalization days (n = 372). For the remainder (n = 145) or 16.5% of the cases, illness severity could not be determined. Using multiple logistic regression, independent predictors of "severe" illness were identified among the systemic cases. Workers coming in contact with OP residue on commodities or in the field ("exposed to residue" or ER) (OR = 4.6, 95% CI = 3.03-7.07) and mixer/loaders/applicators (MLA) (OR = 4.1, 95% CI = 2.72-6.07) were at significantly increased risk of severe illness when compared with cases exposed to OP application drift. Cases with a Spanish surname were also at increased risk of severe illness (OR = 1.8, 95% CI = 1.25-2.73). Increased numbers of OPs per exposure were also associated with severe illness (p < 0.001). Among cases who were exposed to only one OP, severe systemic cases were more likely than mild systemic cases to be associated with exposure to diethyl than dimethyl compounds (OR = 1.6, 95% CI = 1.09-2.38). Severe systemic cases were also more likely than severe skin/eye cases to be associated with exposure to OPs with high toxicity (OR = 5.5, 95% CI = 2.42-12.60) and with exposure to diethyl groups (OR = 4.8, 95% CI = 1.90-12.00). These findings suggest that reducing exposure to OP residues, to OPs with diethyl groups, and to multiple OPs, and exposure during mixer/loader/applicator activities would reduce the risk of OP-related illness.

Occupational hazards to fertility and pregnancy outcome

Occupational reproductive hazards to women have been studied frequently despite the fact that many female reproductive endpoints are not readily observable or routinely recorded in occupational medical records (subfertility, delayed conception, early pregnancy loss, menstrual cycle dysfunction). However, a number of outcomes are fairly readily observable (low birthweight, clinically observed SAB, preterm labor) and medically recorded although they are not generally recorded in the occupational setting. In addition, techniques for observing reproductive outcomes in women are generally less invasive than those in men, particularly with recent developments in urinary monitoring for ovarian function and early pregnancy loss. Although studies of some exposures and outcomes (risk of SAB, low birthweight, or preterm birth with exposure to VDTs or EMFs or exposure to metals and menstrual dysfunction, infertility, or SAB) have shown inconsistent results, a number of findings regarding other associations have been fairly consistent and are very suggestive of causal relationships. Occupational exposure to solvents does appear to increase the risk of dysmenorrhea and SAB, particularly with exposure to organic solvents. Increased risk of adverse reproductive outcomes has also been observed among women working in agricultural settings, but no link has been made to specific exposures. In addition, physical stressors such as shift work, long hours standing, and lifting have been fairly consistently associated with increased risk of SAB or preterm birth. Finally, while complete agreement among studies is lacking, many have observed an increased risk of subfertility or SAB associated with work in medical occupations and with some specific medical exposures, such as nitrous oxide, anesthetic gases and antineoplastic drugs. Much remains to be explored, particularly clarification of the relationship for exposures and outcomes that have shown inconsistent results. These require specific efforts to validate exposures and outcomes, to investigate and control for confounding variables, to consider the effects of multiple comparisons, to study populations of adequate size to provide meaningful statistical analyses, and to make possible the evaluation of dose-response and timing of exposure effects.

Introduction: rationale for an update. Reproductive hazards

More than 104,000 chemical and physical agents have been identified in the workplace, but the effects on reproduction of at least 95% of them have not been assessed. Here, the editors of this volume describe changing demographics in the workplace, which underscore the need for evaluating potential hazards to reproduction. They also review findings regarding occupational reproductive hazards to men and women that have been reported over the past decade.

Workplace policy on hazards to reproductive health

At present, workplace policies regarding reproductive hazards are not regulated directly, and inappropriate policies are occasionally corrected by legal actions or union pressures on the employers. Further, information on reproductive hazards is incomplete; however, employees have a legal right to know available information about hazards, including reproductive hazards, that they face in the workplace. Occupational health personnel play a major role in communicating information about reproductive hazards in the workplace and in implementing company policy and complying with legislation. Regulatory and case law likely will continue to evolve as many issues related to safety from reproductive hazards in the workplace have not yet been resolved.

Childhood cancers associated with parental occupational exposures

Statistics suggest that environmental and occupational exposures may be at least partially responsible for an increased incidence of cancer in children. The authors describe the latest findings in this area of research and look at the methodologic concerns that arise and how they affect the derivation of causal inferences from such studies.

Risk factors for secondary amenorrhea and galactorrhea

OBJECTIVE

Analyses were undertaken to identify factors that may predispose women to secondary amenorrhea or galactorrhea, frequent sources of abnormal reproductive function.

METHODS

Data were gathered from interviews with 252 women with secondary amenorrhea or galactorrhea from four clinical centers, along with neighborhood controls matched to each case. Univariate comparisons were made for clinical and demographic factors of the study subjects.

RESULTS

Patients with amenorrhea and normal prolactin (PRL) levels and their matched controls tended to be younger than those with amenorrhea and elevated PRL or than menstruating patients with galactorrhea alone and their matched controls. Patients with amenorrhea and normal PRL also were significantly more educated and were older at menarche than their controls, while amenorrhea patients with elevated PRL or patients with galactorrhea alone did not differ significantly from their controls in age at menarche or educational level. More patients with galactorrhea alone had reported menstrual pain to their physicians and had significantly longer menstrual periods than their matched controls. Patients with galactorrhea alone also weighed more than their controls 2 years prior to diagnosis, a difference that remained after stratification by parity, although only statistically significant among women who had had one or two pregnancies. Finally, significantly fewer patients with amenorrhea than controls were smokers. Thus, these disorders may not be due to anti-estrogenic effect or to low estrogen levels which have been associated with smoking.

The use of urinary hormonal assessments in human studies

The collection and analysis of urine samples provides a practical method for monitoring female reproductive events in non-laboratory and non-clinic populations. Collection of biologic samples permits objective assessment of reproductive health endpoints in epidemiologic studies and for epidemiologic research purposes can provide validation of information provided by the subjects, especially outcomes which are usually concealed and thus unknown to the participant. Urine sampling has several advantages over the collection of blood samples, such as simplicity, non-invasiveness, and cost efficiency. Several studies have shown that endocrine information similar to that obtained in blood samples can be obtained from assays of daily urine samples. The measurement of human chorionic gonadotropin in daily and selected urine samples has been incorporated into several recent epidemiologic studies focusing on early fetal loss, and ovarian and pituitary hormone metabolites have been measured in daily urine samples to evaluate ovarian function in studies focusing on women's reproductive health. As the strategy of urinary monitoring becomes more accepted as a legitimate research tool, laboratory methods are being modified to improve performance, reduce costs and adapted to sophisticated algorithms using multiple hormonal measurements to identify a number of end-points.

The role of family history in risk of childhood brain tumors

BACKGROUND

Although brain tumors are the second most frequent malignancy in children, relatively little is known about the role of family history in risk of these tumors.

METHODS

Children under the age of 18 years (n = 361) in whom primary brain tumors were diagnosed were identified from eight United States population-based Surveillance, Epidemiology, and End Results registries and compared to matched controls (n = 1083) identified by random-digit dialing. Information regarding family history of birth defects or tumors was obtained, along with data on other potential risk factors, from interviews with the mothers and fathers of the index children.

RESULTS

No significant differences were found in family history of epilepsy. However, moderate elevations in risk were observed for a history of birth defects in maternal relatives, particularly for female propositi. Significantly more mothers (odds ratio [OR] = 1.63, 95% confidence limits [CL] = 1.03, 2.57) and maternal female relatives (OR = 2.15, 95% CL = 1.14, 4.06) of cases than of controls were reported to have had birth defects. History of birth defects in maternal relatives was particularly associated with childhood brain tumors of "other" (not astrocytoma or medulloblastoma) histologic type (OR = 2.37, 95% CL = 1.25, 4.53) and infratentorial tumors (OR = 1.76, 95% CL = 1.06, 2.93). Slight excesses of tumors were observed in paternal relatives of children with astrocytomas (OR = 1.43, 95% CL 0.93, 2.20) or with infratentorial tumors (OR = 1.46, 95% CL 0.97, 2.20). Risk of childhood brain tumors did not increase with the number of relatives affected with brain tumors, breast cancer, leukemia or lymphoma, soft tissue sarcomas, or all of these tumor types combined (the Li-Fraumeni syndrome).

CONCLUSIONS

These findings suggest a modest increase in risk of childhood brain tumors associated with maternal family history of birth defects. Family history of tumors does not appear to contribute appreciably to an increased risk of brain tumors in children.

Classification of adverse reproductive effects can be improved by measurements of multiple biomarkers for ovarian toxicity and early fetal loss

Hormone assays have been developed and applied for monitoring reproductive function using self-collected urine samples in non-clinical populations of women. Early pregnancy loss, menstrual dysfunction, reduced fertility as well as the site of toxicity can now be assessed using daily early morning urine samples. The understanding of the specific limitations of individual assay systems is important, however, to make the best use of these systems. The use of multiple end-points and computer algorithms is suggested to avoid misclassification of adverse reproductive events.

Asthma mortality in California, 1960-1989. Demographic patterns and occupational associations

We analyzed asthma mortality rates in California during the years 1960 to 1989. Sex- and race-specific rates were stratified by age group (0 to 4, 5 to 34, 35 to 64, and 65+ yr) and for all ages directly standardized to the 1970 U.S. age distribution. Observed and expected asthma deaths were also calculated by occupation for the period 1979 to 1981 among persons aged 16 to 64 yr using data from the California Occupational Mortality Study. Asthma mortality rates were strongly associated with increasing age, but no consistent differences were observed between men and women. Mortality rates among blacks under age 65 yr were two to four times the corresponding rate among whites between 1960 and 1989, but this difference was not observed for those over age 65. Asthma mortality rates were calculated for Hispanics and Asians from 1985 to 1989. In this time period the asthma mortality rate ratios for Hispanics were 0.4 to 0.8 compared with the age-stratified rates among whites, 0.1 to 0.2 times the black rates in age categories under 65, and 0.5 times the rate for blacks ages 65 and above. Asthma mortality rates among Asians under 65 yr of age were similar to rates for whites, but for Asians 65 yr of age and over the rate ratios for males and females compared with whites were 1.8 and 1.1, respectively. A decrease of approximately 50% in asthma mortality occurred from 1960 to 1970, and a marked increase occurred between 1975 and 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

Parental smoking and risk of childhood brain tumors

Data from a large, population-based, case-control study were analyzed to assess the role of parental smoking in childhood brain tumors. Parents of 361 cases, newly diagnosed between January 1, 1977 and December 31, 1981 and ascertained from eight Surveillance, Epidemiology, and End Results (SEER) program registries, and 1,083 controls had been interviewed. No significant differences in risks were found to be associated with maternal or paternal smoking at any time (odds ratio (OR) = 0.92 for mothers and 1.06 for fathers), during the year of birth of the child (which included both the prenatal and postnatal periods) (ORs = 0.84 for < 1 pack/day and 1.0 for > or = 1 pack/day for mothers, and 0.68 for < 1 pack/day and 1.07 for > or = 1 pack/day for fathers), or 2 years before the child was born, i.e., the pre-conception period (ORs = 0.75 for < 1 pack/day and 1.01 for > or = 1 pack/day for mothers, and 0.90 for < 1 pack/day and 1.15 for > or = 1 pack/day for fathers). Mothers were also specifically asked if they smoked during the pregnancy, and no association was found compared with never smokers (OR = 1.08, 95% confidence interval (CI) 0.80-1.45) or for ever-smokers who continued to smoke during pregnancy compared with those who stopped smoking during pregnancy (OR = 1.15, 95% CI 0.75-1.78). Finally, no significant increase in risk of brain tumors was found for the child's passive exposure to parental smoking during the period from birth to diagnosis of the brain tumor in the case. The lack of an effect of parental smoking was observed for both the major histologic types and locations of brain tumors. These findings and those from earlier studies provide no support for the hypothesis that parental cigarette smoking influences the risk of brain tumors in children.

Occupational health problems among migrant and seasonal farm workers

Migrant and seasonal farm workers are one of the most underserved and understudied populations in the United States. The total US population of such farm workers has been estimated at 5 million, of whom about 20% live or work in California. Farm workers perform strenuous tasks and are exposed to a wide variety of occupational risks and hazards. Low socioeconomic status and poor access to health care also contribute to existing health problems in this population. Potential farm work-related health problems include accidents, pesticide-related illnesses, musculoskeletal and soft-tissue disorders, dermatitis, noninfectious respiratory conditions, reproductive health problems, health problems of children of farm workers, climate-caused illnesses, communicable diseases, bladder and kidney disorders, and eye and ear problems. Few epidemiologic studies exist of these occupational health problems. No comprehensive epidemiologic studies have assessed the magnitude of occupational health problems among migrant and seasonal farm workers and their dependents. Although the migratory nature of this population makes long-term studies difficult, the development of standardized data collection instruments for health consequences and scientific assessment of farm work exposures and working conditions are vital to characterize and reduce the occupational health risks in farm workers.

Occupational medicine: electromagnetic field exposure and risks of cancer in children

The Scientific Board of the California Medical Association presents the following inventory of items of progress in occupational medicine. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established both as to scientific fact and important clinical significance. The items are presented in simple epitome and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, research workers, or scholars to stay abreast of these items of progress in occupational medicine that have recently achieved substantial degree of authoritative acceptance, whether in their own field of special interest or another.The items of progress listed below were selected by the Advisory Panel to the Section on Occupational Medicine of the California Medical Association, and the summaries were prepared under its direction.

Estrogen and androgen levels in women treated with radiation for cervical cancer--possible influence on breast cancer risk

In 1984-1985, estrogen and androgen levels in blood sera were measured in 320 women who had been treated for cervical cancer in the early 1960s. Study subjects were from US clinics in Baltimore, Maryland; Boston and Norfolk, Massachusetts; Buffalo, New York; Houston, Texas; and San Juan, Puerto Rico. These clinics had participated in a larger international follow-up study of cervical cancer in which a 20-30% reduction in breast cancer risk was linked to prior pelvic irradiation, even when treatment occurred after menopause. Overall, the 203 irradiated and 117 nonirradiated women had similar mean levels of estradiol, estrone, androstenedione, and testosterone. However, there appeared to be negative, albeit inconsistent, trends for androstenedione, testosterone, and estrone, suggesting that the irradiated women had lower levels of these hormones when compared with the nonirradiated women. These differences did not reach the level of statistical significance. While chance could partially explain these findings, it is plausible that the frequently observed protective association of breast cancer with pelvic irradiation could be due in part to a decrease in steroid hormones that is secondary, perhaps, to adrenal irradiation.

Methodological considerations in the study of parental occupational exposures and congenital malformations in offspring

The existence of hazardous substances in the workplace has raised concerns about the potential of these substances for adverse reproductive effects. Identification of associations between parental occupational exposures and congenital malformations in the offspring may provide the opportunity for preventing such exposures and thus reduce the risk of malformations. However, there are many methodological considerations inherent in studying the potential relation between parental occupational exposures and congenital malformations in the offspring. Considerations relating to outcome include methods and timing of ascertaining cases with malformations, diagnostic criteria, and problems in grouping malformations for purposes of analysis. With regard to measuring exposures, issues include methods for obtaining valid estimates of the nature, duration, timing of exposure, and exposure-response relationship. Other methodological issues discussed include selection of appropriate reference groups, sample size, and multiple hypothesis testing.

Sensitive and specific monoclonal antibody recognition of human lung cancer antigen on preserved sputum cells: a new approach to early lung cancer detection

Murine monoclonal antibodies (Mabs) to a glycolipid antigen of small-cell (SCC) and a protein antigen of non-small-cell lung cancer (NSCC) were applied to preserved sputum specimens from individuals who participated in The Johns Hopkins Lung Project (JHLP). In that study, undertaken in 1973 to evaluate the efficacy of sputum cytology screening, half of the high-risk participants (5,226 men, greater than or equal to 45 years of age, currently smoking greater than or equal to 1 pack of cigarettes per day) were randomly assigned to produce specimens for cytopathological analysis. During regular screenings over the next 5 to 8 years, 626 (12%) showed moderate (or greater) atypia. Sixty-nine of these (26 who progressed to cancer, 43 who did not) were randomly selected for a blinded improved Mab immunostaining protocol in the present study. Satisfactory specimens with morphologic atypia immunostained positively in 14 of the 22 patients who eventually progressed to cancer (sensitivity 64%), and were nonreactive in 35 of the 40 patients who did not progress to lung cancer (specificity 88%). Review of the true positive specimens (14/22 atypias) showed that they were collected 24 months in advance of diagnosis. In contrast, the 8/22 false negative atypias (failure to stain) showed that they were collected for an average of 57 months preceding the diagnosis of cancer. Subsequent specimens (average, 26 months before cancer) from participants who were originally considered "false negative" did stain positively improving sensitivity to 91% among specimens collected for an average of 2 years in advance of the clinical appearance of lung cancer. Specificity remained at 88%. Recognition of neoplastic antigen expression 2 years in advance of clinical cancer may be a valuable intermediate end point in studies of lung cancer prevention, detection, and therapy.

The interaction of alcohol consumption and oral contraceptive use on lipids and lipoproteins

Oral contraceptive (OC) use and alcohol consumption have been shown to alter the levels of lipids and lipoproteins in the blood. The effect of alcohol consumption on levels of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, LDL-B, Apo-A1, the ratio of HDL cholesterol/total cholesterol, HDL cholesterol/LDL cholesterol, and the ratio of LDL cholesterol/LDL-B among normal healthy young women before initiation of oral contraceptives and after six months of oral contraceptive use are both described. Of primary interest is the mediating effect of alcohol consumption on the association between steroid usage and blood lipid values. At baseline, ethanol consumption was found to be positively associated with triglycerides, HDL-C, and Apo-A1 and negatively associated with LDL-C/LDL-B. After adjustment for several covariables, alcohol consumption was found to be positively associated with the increases in triglycerides and in Apo-A1 observed at 3 and 6 months after initiation of OCs. Since these two parameters are believed to have opposite relationships to cardiovascular disease, the effect of alcohol consumption remains uncertain.

Ectopic pregnancy and prior induced abortion

As part of the Women's Health Study, a case-control study conducted in nine cities in the United States, women hospitalized with an ectopic pregnancy and women hospitalized with non-gynecologic, medical or surgical diagnoses were interviewed concerning past reproductive history. There were 462 women meeting eligibility criteria in the ectopic pregnancy case group and 2326 women meeting the criteria for the control group. After adjustment for a number of possible confounders, the relative risk of ectopic pregnancy for women with a history of one induced abortion was 1.0 (95% confidence limits: 0.5 to 1.8) and was 0.9 (95% confidence limits: 0.8 to 1.1) for women with a history of two or more prior induced abortions. These results suggest that prior induced abortion does not significantly increase the risk of subsequent ectopic pregnancy.

The effect of physician terminology preference on coronary heart disease mortality: an artifact uncovered by the 9th revision ICD

We dual coded 2,268 deaths due to heart disease occurring in Maryland, using the 8th and 9th revisions of the International Classification of Diseases (ICDA-8, Adapted for Use in the United States, and ICD-9). Certifier preference was for generalized cardiovascular terms rather than terms specific to the heart, resulting in an artifactual change in chronic ischemic heart disease death (IHD) rates in Maryland between 1978 and 1979 because the 8th and 9th ICD revisions classified these terms differently. Medical examiners were more likely to use these generalized cardiovascular terms as were physicians who went to certain medical schools in the state. The physician's terminology preference was associated with the sex and race of the decedent and was related to aspects of the patient's medical care. The ICD should be modified in the 10th revision to allow for the separate classification of generalized cardiovascular terminology within the ischemic heart disease category.

Headache, hyperprolactinemia, and prolactinomas

The present study was undertaken to investigate whether headache in women with nonpuerperal hyperprolactinemia was related to elevated serum prolactin (PRL) levels or the presence of a PRL-secreting pituitary adenoma. The subjects were 469 women seen initially during the period of 1973 to 1979 at four clinical centers with the complaints of secondary amenorrhea and/or galactorrhea, 212 of whom were subsequently diagnosed as having a prolactinoma. Headaches were four times more frequent (relative odds = 3.92; 95% confidence interval = 1.54 to 9.97) in the presence of an adenoma than in its absence. This effect was not altered by adjustment for PRL level or study center, nor could it be explained by confounding due to age, occupation, level of education, use of oral contraceptives, cigarette smoking, ethnic group, or history of head injury. Hyperprolactinemia was associated with headache only if a prolactinoma was present (chi 2 = 9.524; P = .002) and not in the absence of a prolactinoma (chi 2 = 1.547; P = .214). These findings suggest that the space-occupying mass effect of a prolactinoma is responsible for headache in women with nonpuerperal hyperprolactinemia. Despite its nonspecific nature, headache may be a useful indicator of the presence of an occult prolactinoma in women with secondary amenorrhea and/or galactorrhea.

Race and primary open-angle glaucoma

A comparison of racial distributions for three groups of patients showed that 115 of 140 patients (81.6%) with open-angle glaucoma, 221 of 392 patients (56.4%) with ocular hypertension, and 1,028 of 2,109 patients (48.7%) in a random sample were black. Average age at diagnosis was significantly (P = .006) higher for whites than for blacks (69.1 years vs 63.7 years). Black patients with primary open-angle glaucoma had a significantly larger mean cup-disk ratio (P less than or equal to .002) and a higher but not significantly higher mean intraocular pressure at the time of diagnosis. Advanced glaucomatous visual field loss was more frequent at the time of diagnosis in blacks (43 of 129 patients or 33.3%) than in whites (five of 27 patients or 18.5%), but this difference was not significant.

Diet and other risk factors for cancer of the pancreas

The findings of a case - control study of cancer of the pancreas, which was conducted in the Baltimore metropolitan area, are reported. Two hundred one patients with pancreatic cancer were matched on age (+/- 5 years), race, and sex to hospital and non-hospital controls, the latter selected by random-digit-dialing (RDD). All subjects were interviewed regarding diet, beverage consumption, occupational and environmental exposures, and medical and surgical history. Significantly decreased risks were associated with consumption of raw fruits and vegetables and diet soda, and significantly increased risks were associated with consumption of white bread when cases were compared with hospital and RDD controls. A significantly reduced risk was associated with consumption of wine when cases were compared to RDD controls. Risk ratios for consumption of coffee were not significantly different from one, although there appeared to be a dose - response relationship in women. A moderate but statistically nonsignificant increase in relative odds was found for cigarette smoking, and cessation of smoking was associated with a marked reduction in risk. No significant associations were found with particular occupational exposures. Tonsillectomy was associated with a significantly reduced risk, a finding that has been observed for other cancers as well. The current evidence indicates that pancreatic cancer is likely to result from a complex interaction of factors and suggests that the study of its etiology requires a multidisciplinary approach involving both laboratory and epidemiologic components.