The prevalence of breast implants among women in the United States.

Estimates of the number of women with breast implants have varied from less than one million to over three million. Most of these appear to be extrapolations from either industry production figures or reports of surgical procedures. In late 1989 under contract to the Dow Corning Corporation, Market Facts, Inc. conducted a mail survey of 40,000 households selected to be representative of the population of the United States. They received responses from 70.7%. Based upon the data collected, 8.08 per 1,000 women in the United States reported ever having had some type of breast implant. Approximately 60% of the procedures had been done for cosmetic reasons. Most of the women were White (94.6%) and rates were highest in the South or West. Although younger women were more likely to have had implants for augmentation and older women for reconstruction presumptively following breast cancer surgery, the largest prevalences for either of the two procedures were in the 45 to 54 year old age group. Breast implant prevalence also increased in direct proportion to household income with the largest increases being related to cosmetic augmentation. Based upon the data collected in this survey, the total number of women in the United States in late 1989 who had ever had breast implants was estimated to be 815,700 (95% confidence interval: 715,757-924,729).

HIV antibody testing in young, urban adults.

We surveyed men and women aged 21 to 34 years to determine the rates of human immunodeficiency virus (HIV) antibody testing in blacks and whites of diverse education levels in four US cities. Responses to the anonymous, mailed questionnaire were received from 90% of 777 white women, 64% of 734 black women, 79% of 677 white men, and 48% of 541 black men. The percentages reporting HIV testing for these four race-gender groups were 29%, 22%, 30%, and 38%, respectively. The percentages reporting testing that was voluntarily sought (ie, not in connection with blood donation, military service) were 16%, 14%, 18%, and 22%, respectively. In each race-gender group, roughly half of those who had not been tested said they "might have a blood test for the AIDS virus in the future". Education level was not correlated with HIV-testing frequency. Blacks were significantly less likely than whites to be aware of "a blood test that can detect the AIDS virus infection" (58% vs 77%), but blacks who knew of the test were more likely than whites to have been tested (47% vs 37%). Eleven percent of subjects reported at least one major risk factor for HIV infection. In these people, HIV testing was most common among homosexually active men (56% tested; 52% voluntarily sought), intermediate among injection drug users (40% tested; 31% voluntarily sought), and least common among the sexual partners of injection-drug users (21% tested; 11% voluntarily sought). Health education programs need to communicate the availability of, and need for, anonymous HIV testing.

Risk factors for gestational diabetes in black population.

In a long-term longitudinal study of gestational diabetes mellitus in Black women, risk factors that were identified were age, obesity, a family history of diabetes, and the presence of hypertension. Poor predictors were a history of a previous large-for-date infant, parity, and age at first pregnancy. The prevalence of smooth muscle and nuclear autoantibodies was higher in gestational diabetic subjects. Gestational diabetic subjects who required insulin for glycemic control were more obese, had a lower frequency of the Bf-F phenotype and a higher frequency of the Bf-F1 phenotype, and had a lower frequency of the type 2 allele at the polymorphic locus adjacent to the insulin gene. Restriction-fragment-length polymorphisms flanking the insulin and apolipoprotein A-I and C-III genes, although not associated with gestational diabetes mellitus, may be associated with hyperlipidemia and subsequent atherosclerosis.

Plasma homocyst(e)ine, folate, and vitamin B-12 concentrations and risk for early-onset coronary artery disease.

High plasma homocyst(e)ine (Hcy) concentrations may be a determinant of coronary artery disease (CAD). Folate and vitamin B-12 are required for the primary metabolic pathway to reduce Hcy concentrations. The interrelationships of Hcy and these two vitamin cofactors were investigated in a case-control study of 101 white males aged 30-50 y with angiographically demonstrated CAD, and 108 white male, similarly aged, control subjects living in the same community as the patients. The odds ratio (OR) of CAD per quartile increase of plasma Hcy concentration based on control values was 1.6 (95% CI: 1.3, 2.1). After age, HDL and LDL cholesterol, body mass index, smoking, hypertension, and diabetes were controlled for, Hcy remained an independent risk factor (OR: 1.4; 95% CI: 1.0, 2.0). The OR change per quartile increase of folate concentration was 0.8 (95% CI: 0.6, 1.0). This difference was reduced (OR: 0.9; 95% CI: 0.7, 1.2) after Hcy adjustment. No difference in the geometric mean of vitamin B-12 concentration was found between patients and control subjects, both 5.8 nmol/L. However, after Hcy and the other CAD risk factors were controlled for, the OR per quartile increase in vitamin B-12 concentration was 1.5 (95% CI: 1.0, 1.8). Reduction in plasma Hcy by interventions to increase plasma folate concentration may decrease CAD risk.

Concentrations of Lp(a) in black and white young adults: relations to risk factors for cardiovascular disease.

The purpose of this report is to compare the distribution of total lipoprotein(a) [Lp(a)] mass in a population-based sample of blacks and whites, and to investigate the association of Lp(a) with other cardiovascular risk factors. A cross-sectional study design was used. Black and white men and women (n = 4125), aged 23-35 from the Coronary Artery Risk Development in Young Adults Study had the following data collected: Lp(a), lipids and lipoproteins, other metabolic parameters, anthropometry, physical activity, dietary intake, cigarette use, and alcohol use. Blacks had concentrations of Lp(a) approximately three-fold higher than whites. Medians were: black men 21.5 mg/dL, black women 23.9 mg/dL, white men 6.1 mg/dL, and white women 6.4 mg/dL. Lp(a) concentrations were higher in women than in men. Lp(a) was not consistently associated with smoking, alcohol consumption, physical activity, dietary fat, or obesity. In stepwise regression analyses in both blacks and whites, Lp(a) was consistently associated with low-density lipoprotein (LDL) cholesterol, fibrinogen, and apoB; regression models explained about 7% of the variance in Lp(a). In whites, Lp(a) tended to be higher in those with a positive family history of myocardial infarction. The large differences in Lp(a) between blacks and whites, and the absence of association with many other variables are consistent with previous suggestions that Lp(a) concentration is in large part genetically determined. The association of Lp(a) with LDL and fibrinogen, two strong risk factors for cardiovascular disease (CVD), could represent part of the mechanism of the CVD risk associated with Lp(a) in other studies. Longitudinal data are needed to determine the extent to which Lp(a) will independently predict disease, especially in diverse ethnic groups.

Seven-year trends in plasma low-density-lipoprotein-cholesterol in young adults: the CARDIA Study.

To identify determinants of recent secular trends in lipids and characterize their influence on age-related increases in LDL-cholesterol, we examined a cohort of black and white men and women aged 18-30 in 1985-1986. Secular trends were determined by comparing participants aged 25-30 at baseline with those aged 25-30 at year 7 (2788 and 1395 participants, respectively). LDL-cholesterol was lower among those 25-30 at year 7 (5.9 to 10.2 mg/dL, depending on race-sex group; P < 0.001); weight was higher (8.3 to 12.5 lb; P < 0.001); Keys score was lower (-4.2 to -7.3 units; P < 0.001); and use of oral contraceptives was greater (white women only, P < 0.01). Among 4086 participants followed for 7 years, LDL-cholesterol changed little or decreased, despite substantial weight increases in all groups (11.6 to 19.0 lb; P < 0.001). Keys scores decreased by 6.1 to 8.0 units, and use of oral contraceptives decreased (P < 0.001). Declining secular trends in LDL-cholesterol occurred despite upward trends in weight; the decline was associated with lower dietary fat and cholesterol and offset expected age-related increases in LDL-cholesterol.

The prevalence of women with breast implants in the United States--1989.

Most estimates of the number of women with breast implants appear to be extrapolations of industry or clinical data. While both provide valuable information, the former about the total number of devices ever produced or sold and the latter about the cumulative number of surgeries performed, neither can be used to directly estimate the prevalence of women with silicone gel or saline implants. In 1989, Market Facts, Inc., conducted a mail survey of 40,000 households chosen as representative of the population of the United States and received responses from 70.7%. Overall, the prevalence was 8.08 per 1,000 women with about 60% of the devices reportedly implanted for cosmetic reasons. The procedure was more common among Whites of the higher socio-economic classes. Based upon the results of this survey, the total number of US women in 1989 with breast implants was estimated to be 815,700 (95% confidence interval: 715,757-924,729).

Symptom prevalence in the elderly. An evaluation of age, sex, disease, and medication use.

Prevalence of reported symptoms was studied in 1927 women and 1140 men over 65 years of age in an ambulatory health screening program. Reports of 28 common symptoms were obtained from a standardized questionnaire completed by participants at the time of their fourth annual visit to the program. A comparison was made of the prevalence of specific symptoms by sex, age, disease states, and drug use patterns. The most common symptoms reported by women were nocturia (80.4%), swollen feet or ankles (30.5%), cold feet and/or legs (28.6%), and irregular heartbeat (23.2%), whereas men complained most often of nocturia (79.8%), irregular heartbeat (24.8%), cold feet and/or legs (23.6%), and tinnitus (23.1%). Women reported a mean of 3.99 symptoms compared with 3.22 reported by men (P less than .0001). In women their was a statistically significant association for most symptoms in subjects reporting the use of medication compared with a group who did not use medication. In men the use of medication was less highly correlated with reports of symptoms. Nearly 100% of participants reported having at least one disease state. The number of symptoms reported was strongly related to the number of disease states, and after adjusting for diseases, women reported more symptoms than men. The best predictor of symptom prevalence was the number of disease states followed by the number of drugs used and then age.

Cataracts in Dunedin Program participants: an evaluation of risk factors.

A geriatric health screening program in Dunedin, Florida, was used to evaluate risk factors leading to development of cataracts. A total of 2,787 participants completed the fourth yearly visit to the program. At the time of the fourth visit, 49.3% of women (mean age 75.1 years) and 38.2% of men (mean age 75.4 years) reported the presence of cataracts. Age was found to be the most significant risk factor in cataract development (P less than .0001). Both men and women with cataracts had significantly lower serum cholesterol concentrations than subjects without cataracts. After adjusting for age and sex, diazepam (P less than .03), furosemide (P less than .04), isosorbide (P less than .003), and ibuprofen (P less than .03) were found to be positively associated with cataracts; triamterene (P less than .05) had a negative association, indicating a protective relationship. Aspirin was not shown to have a protective effect on reported cataracts.

Vitamin E effect on symptoms and laboratory values in the elderly.

The effect of vitamin E use on selected medical disorders and laboratory parameters was studied in a large ambulatory elderly population. Information obtained from a standardized questionnaire concerning reports of numerous clinical disorders, such as hypertension, fatigue, and vaginal bleeding, was used to determine whether the use of vitamin E predisposed to those conditions. During a 2-year period, information was available on 369 vitamin E users and 1,861 non-users. No differences were noted in the prevalence of reported clinical disorders between the two groups, except that men using vitamin E complained more often of shortness of breath (p less than .04) and angina (p less than .03). There were no significant differences between vitamin E users and controls in any hematologic parameters studied. After the groups had been adjusted for age and sex differences, only one biochemical parameter, serum glutamic-oxaloacetic transaminase (SGOT) in men, was found to be significantly different in vitamin E users as compared with controls. Use of vitamin E by the participants in this study appeared to have little influence on clinical disorders or hematologic or biochemical parameters.

Sexually transmitted diseases among young heterosexual urban adults.

A self-administered, confidential survey of respondents' history of selected sexually transmitted disease (STD) was conducted in 1987-88 among adults enrolled in a multicenter study of cardiovascular disease. Respondents (and response rates) included 535 white men (78 percent), 694 white women (89 percent), 262 black men (48 percent), and 472 black women (64 percent), ages 21 to 40 years at the time of the survey. Among those who were heterosexually active, 43 percent of black women, 37 percent of black men, 33 percent of white women, and 21 percent of white men reported ever having had at least one STD in the survey. A history of syphilis or gonorrhea was more commonly reported by blacks than whites; a history of genital herpes, chlamydia, or genital warts was more commonly reported by women than men. Independent risk factors for having had at least one STD in the survey included female sex; use of cocaine, amphetamines, or opiates; and lifetime number of sex partners. The number of sex partners was the most predictive risk factor. Black race was a significant marker for other, unidentified STD risk factors. The data show a high prevalence of a lifetime history of STD among young heterosexual urban U.S. adults with possible implications for the future spread of human immunodeficiency virus infection.

Changes in sexual behavior by young urban heterosexual adults in response to the AIDS epidemic.

Young adults residing in four States were enrolled in the period 1985-88 in a multicenter study of cardiovascular disease risk factors. In 1989, 2,729 members of the group were given a self-administered questionnaire that included questions on changes in sexual behavior that subjects had made in response to the epidemic of acquired immunodeficiency syndrome (AIDS). The final sample of 1,601 young, heterosexual, urban respondents included 412 white men, 568 white women, 224 black men, and 397 black women, all ages 21 to 40 years. Overall, nearly 50 percent of the sample reported having made at least one change in their sexual behavior in response to the AIDS epidemic to decrease their risk of becoming infected by the human immunodeficiency virus. The mean number of changes was 0.8 for white men, 1.1 for white women, 1.6 for black men, and 1.5 for black women. Change was reported more frequently by black respondents than white, with no significant sex differences. The categories of respondents reporting behavior changes were more often young, with a history of recreational drug use, with more sex partners, or having had anal intercourse. The most commonly reported behavior changes were reducing the number of sex partners and being more careful in partner selection. Of the 54 percent of respondents who did not report any change in sexual behavior, about 70 percent reported unprotected sex with more than one partner in the previous year. Significant sexual behavior change in response to the AIDS epidemic remains a goal for health education efforts.

Refrigeration of blood samples prior to separation is essential for the accurate determination of plasma or serum zinc concentrations.

An evaluation of refrigeration (7 degrees C) to prevent falsely high plasma or serum zinc concentrations owing to elapsed time between blood collection and centrifugation was performed. At room temperature (23 degrees C), both plasma and serum zinc concentrations increased significantly, if blood samples were stored uncentrifuged. Plasma zinc concentrations increased 6.3% at 1 h and 40.7% at 24 h, whereas serum zinc concentrations increased only 0.9% at 1 h and 12.5% at 24 h at room temperature. When blood samples were stored uncentrifuged in the refrigerator for up to 24 h, there were no significant increases in zinc concentrations in either plasma or serum. These findings suggest that plasma or serum separation should be performed immediately after blood drawing to obtain accurate zinc concentrations, and if this is not feasible, the samples should be immediately refrigerated and separation performed within eight hours.

An assessment of critical anthropometric dimensions for predicting the fit of a half-mask respirator.

The purpose of this study was to determine if facial dimensions for a group of subjects were predictive of the fit factors measured while one brand of half-mask respirator was worn. Fit factors and 12 facial dimensions measured on 30 female and 38 male subjects were analyzed by correlation coefficients; weighted, multiple linear regression; and discriminant analysis. Data were analyzed for all subjects, gender subgroups, a race subgroup (whites only), and race/gender subgroups. Significant correlation coefficients with the log-transformed fit factors were found for four dimensions; four dimensions had significant coefficients in four or more multiple linear regression models. Only two dimensions had significant coefficients in four or more discriminant analysis models. Menton-subnasale (lower face) length was the only dimension included in all three of these groups. Gender-specific regression models had very high coefficient of determination values (R2 > 0.85). Discriminant analysis of the data for all subjects and race/gender subgroups found very good predictive scores for statistical software-generated models and menton-subnasale length alone; these scores were significantly better than those for the model with the respirator test panel dimensions (face length and lip width). These analyses found that facial dimensions were good predictors of respirator fit for those subjects wearing one brand of half-mask respirator. Lower face length was consistently indicated as being correlated or associated with fit. These results would indicate that dimensions other than those currently used may be more appropriate to define a half-mask respirator test panel.

Estimating a relative risk across sparse case-control and follow-up studies: a method for meta-analysis.

Meta-analysis is the quantitative technique of combining results from different studies. There is a variety of procedures available for combining effect measures across epidemiologic studies. None of these methods provides an overall effect estimate when the data are sparse within studies and come from different study designs. In this paper we discuss the statistical relations between case-control studies and two types of follow-up studies. We use these relations to develop an exact methodology for combining results across study designs. We also use these relations to derive Mantel-Haenszel type formulae for summarizing results across studies. We illustrate these techniques with data pertaining to breast implants and connective tissue disease.

Distribution of faceseal leak sites on a half-mask respirator and their association with facial dimensions.

Faceseal leaks on one brand of half-mask respirator worn by 73 human subjects were identified by deposition of a fluorescent tracer aerosol during a standard quantitative fit test. The identified leaks were categorized according to their location and shape. It was found that about 89% of all observed leaks occurred at the nose or chin or were multiple leaks which included these sites. Fit factors for these types of leaks were significantly lower than for other types of leaks. About 73% of all leaks approximated the shape of a slit rather than a round orifice, and the prevalence of these leaks was affected by gender. Significant association of facial dimensions and leak sites were found. Most of these were attributed to differences in gender, and only a very small percentage were for the facial dimensions used to define the Los Alamos respirator test panel. Significant correlation of facial dimensions and fit factor were found for only three facial dimensions; none of which are used to define the test panel. Evidence of airflow streamlining within the facepiece was observed on 22% of the subjects. Results of this study indicate that respirator leakage is strongly affected by nose and chin leaks, that gender is a factor in how a respirator fits, and that consideration should be given to including nasal dimensions when defining a respirator test panel and selecting a respirator for an individual wearer.

A meta-analysis of breast implants and connective tissue disease.

Case reports have raised questions about an increased risk of connective tissue diseases (CTDs) among women with breast implants. From the reviews of more than 2,600 manuscripts, abstracts, and dissertations, this meta-analysis included 13 epidemiology studies that provided a relative risk (RR) estimate for the possible association between breast implants and CTDs. The meta-analysis summary RR was 0.76 for CTD in general (95% confidence interval [CI]: 0.55, 1.04; homogeneity p-value = 0.073) and was 0.98 for scleroderma (95% CI: 0.57, 1.64; homogeneity p = 0.006). Irrespective of which studies were aggregated in this meta-analysis, there was no significant increased risk for scleroderma, rheumatoid arthritis, or CTD in general. Conclusions from this study are consistent with the most recent review by the British Medical Devices Agency that found no scientific evidence to date of an increased risk of CTD associated with silicone gel breast implants.