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D Degnan

Publications and source records attributed to D Degnan.

10 recordsLinked to original sources
PubMed2001

Plasma 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) levels and immune response.

For determination of whether plasma 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) pesticide levels (< or =1-32 ppb) are associated with immune suppression or DNA damage in lymphocytes, 302 individuals residing in Moore County, North Carolina, in 1994-1996 provided a blood specimen, underwent a skin test, and answered a questionnaire concerning factors affecting plasma organochlorine pesticide levels and the immune system. The blood specimens were analyzed for levels of plasma DDE (a metabolite of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), numbers and types of blood cells, immunoglobulin levels, mitogen-induced lymphoproliferative activity, and lymphocyte micronuclei. When DDE levels were categorized as 1 or less, more than 1 to 2, more than 2 to 4.3, more than 4.3 to 7.6, and more than 7.6 ppb, individuals with higher plasma DDE levels had lowered mitogen-induced lymphoproliferative activity (concanavalin A, range: 74,218 dropping to 55,880 counts per minute, p = 0.03) and modestly increased total lymphocytes (range: 2.0-2.3 x 10(3)/microl, p = 0.05) and immunoglobulin A levels (range: 210-252 mg/dl, p = 0.04). There were no consistent differences in response to the skin tests by plasma DDE levels. Plasma DDE levels were not associated with a higher frequency of micronuclei. The authors conclude that relatively low levels of plasma DDE are associated with statistically significant changes in immune markers, although the magnitude of the effects are of uncertain clinical importance.

Adolescent↗
PubMed2000

Effects on the immune system associated with living near a pesticide dump site.

In this paper, we report results of the second phase of a larger study designed to evaluate the effects on the immune system of living near a Superfund site containing organochlorine pesticides, volatile organic compounds, and metals. Phase II was conducted to determine whether living near the site, consisting of six locations in Aberdeen, North Carolina, is associated with higher plasma organochlorine levels, immune suppression, or DNA damage. Each of 302 residents of Aberdeen and neighboring communities provided a blood specimen, underwent a skin test, and answered a questionnaire. Blood specimens were analyzed for organochlorine pesticides, immune markers, and micronuclei. Of 20 organochlorines tested, only DDE was detected in the blood of participants (except for one individual). Age-adjusted mean plasma DDE levels were 4.05 ppb for Aberdeen residents and 2.95 ppb (p = 0.01) for residents of neighboring communities. Residents of 40-59 years of age who lived within a mile of any site, but particularly the Farm Chemicals site, had higher plasma DDE levels than residents who lived farther away. Residents who lived near the Farm Chemicals site before versus after 1985 also had higher plasma DDE levels. Overall, there were few differences in immune markers between residents of Aberdeen and the neighboring communities. However, residents who lived closer to the dump sites had statistically significantly lower mitogen-induced lymphoproliferative activity than residents who lived farther away (p < 0.05). Residential location was not consistently associated with frequency of micronuclei or skin test responses. Although some statistically significant differences in immune markers were noted in association with residential location, the magnitude of effects are of uncertain clinical importance.

Adolescent↗
PubMed1997

Geographic information systems: their use in environmental epidemiologic research.

Advances in geographic information system (GIS) technology, developed by geographers, provide new opportunities for environmental epidemiologists to study associations between environmental exposures and the spatial distribution of disease. A GIS is a powerful computer mapping and analysis technology capable of integrating large quantities of geographic (spatial) data as well as linking geographic with nongeographic data (e.g., demographic information, environmental exposure levels). In this paper we provide an overview of some of the capabilities and limitations of GIS technology; we illustrate, through practical examples, the use of several functions of a GIS including automated address matching, distance functions, buffer analysis, spatial query, and polygon overlay; we discuss methods and limitations of address geocoding, often central to the use of a GIS in environmental epidemiologic research; and we suggest ways to facilitate its use in future studies. Collaborative efforts between epidemiologists, biostatisticians, environmental scientists, GIS specialists, and medical geographers are needed to realize the full potential of GIS technology in environmental health research and may lead to innovative solutions to complex questions.

Electromagnetic Fields↗
PubMed1993

Increasing mammography utilization: a controlled study.

BACKGROUND: Despite the effectiveness of breast cancer screening for women older than 50 years of age, only about one third of these women in the United States receive annual mammography. PURPOSE: This study was designed to determine if a community-wide intervention could increase use of mammography screening for breast cancer. Secondary end points were determination of changes in women's knowledge and attitudes toward mammography and physicians' self-reported screening practices. METHODS: We conducted a controlled study from January 1987 through January 1990 in two eastern North Carolina communities--New Hanover County (the experimental community) and Pitt County (the control community). Before development and implementation of the intervention program in New Hanover County and after the program had been in operation for 1 year, 500 women of ages 50-74 years and all primary-care physicians in each community were interviewed by telephone. In these interviews, we determined the use of mammography for breast cancer screening and the knowledge and attitudes about it. We also established the number of screening mammograms performed in 1987 and 1989 in each county and reviewed medical records to determine the percentage of women the physicians had referred for mammograms. RESULTS: The percentage of women who reported receiving a mammogram in the previous year increased from 35% to 55% in the experimental community and from 30% to 40% in the control community (difference of differences, 10%; P = .03 after adjustment for race, education, age, and having a regular doctor; 95% confidence interval, 1%-18%). Increases were greater in New Hanover County regardless of age, race, income, and education. However, the increase was less for Black women than for White women, both overall and in most demographic subgroups. The total number of mammograms performed increased 89% in the experimental community and 45% in the control community. Women's knowledge about mammography changed little, but the intention to get a mammogram increased 30% in New Hanover County, compared with a 17% increase in Pitt County--a statistically significant difference (P < .01). Physician reports and medical record reviews in the two communities showed similar increases in the number of mammograms ordered. CONCLUSIONS: A community-wide effort to increase use of breast cancer screening was successful, but more work must be done to reach the National Cancer Institute's goal of annual mammograms for 80% of women of ages 50-74.

Age Factors↗
PubMed1992

Measuring the use of mammography: two methods compared.

Population studies often estimate mammography use using women's self-reports. In one North Carolina county, we compared self-report surveys with a second method--counting mammograms per population--for 1987 and 1989. Estimates from self-reports (35% in 1987, 55% in 1989) were considerably higher than those from mammogram counts (20% in 1987, 36% in 1989). We then confirmed 66% of self-reports in the past year. Self-reported use is more accurate regarding whether a woman has had a mammogram than when she had it, but self-reports accurately measure change over time.

Aged↗
PubMed1991

Mammography and age: are we targeting the wrong women? A community survey of women and physicians.

To determine mammography use among women with a broad range of ages, the authors surveyed women aged 30 to 74 years and physicians practicing primary care in two eastern North Carolina counties. Twenty-five percent of women in their 30s had ever had a mammogram, and 34% intended to have one in the coming year. From 45% to 52% of women in their 40s, 50s, and 60s had ever had a mammogram, and 55% to 57% intended to have one in the next year. Thirty-seven percent of women aged 70 to 74 years had ever had a mammogram, and 40% intended to have one in the following year. Nineteen percent of physicians reported screening nearly all women aged 30 to 39 years, and 14% screened few women aged 50 to 74 years. Younger women were more worried about breast cancer than older women and assessed their risk as higher, attitudes that were generally associated with higher mammography utilization. These community surveys suggest that mammography use may be excessive among younger women; older women continue to be underscreened.

Adult↗
PubMed1990

How best to teach women breast self-examination. A randomized controlled trial.

OBJECTIVE: To compare three methods for teaching breast self-examination. DESIGN: Randomized controlled trial with factorial design. SETTING: A general medicine group practice in a university hospital. PATIENTS: Continuing-care patients from 40 to 68 years of age. Of 456 eligible women, 156 refused participation, 300 were randomly assigned, 269 completed assigned interventions, and 260 completed the post-test 1 year later. INTERVENTIONS: One third of patients received nurse instruction stressing tactile skills (Mammacare group) (Mammatech Corporation, Gainesville, Florida); one third, traditional nurse instruction emphasizing technique (traditional group); and one third, no nurse instruction (control group). Half of each group received physician encouragement. MEASUREMENTS AND MAIN RESULTS: One year later, women in the Mammacare group found more lumps (mean, 57%; 95% CI, 54% to 60%) in manufactured breast models than did those in the traditional (mean, 47%; CI, 44% to 51%) and control (mean, 45%; CI, 42% to 48%) groups. Lump detection specificity was unaffected. Self-reported examination frequency rose in all groups, to 5.1 times per 6 months in the traditional group, 4.2 in the Mammacare group, and 3.9 in the control group. Physician encouragement did not improve sensitivity, specificity, or overall frequency. Women in the Mammacare group used more of seven examination techniques (4.9) than did those in the traditional (3.9) or control (3.2) groups (P less than 0.001). No group increased health care use or reported more overall worry about breast cancer. CONCLUSIONS: Mammacare instruction resulted in more long-term improved lump detection and examination technique use than did traditional instruction or physician encouragement. Breast self-examination instruction should emphasize lump detection skills.

Adult↗
PubMedDate not supplied

Do waste incinerators induce adverse respiratory effects? An air quality and epidemiological study of six communities.

The purpose of the study presented here was to simultaneously measure air quality and respiratory function and symptoms in populations living in the neighborhood of waste incinerators and to estimate the contribution of incinerator emissions to the particulate air mass in these neighborhoods. We studied the residents of three communities having, respectively, a biomedical and a municipal incinerator, and a liquid hazardous waste-burning industrial furnace. We compared results with three matched-comparison communities. We did not detect differences in concentrations of particulate matter among any of the three pairs of study communities. Average fine particulate (PM2.5) concentrations measured for 35 days varied across study communities from 16 to 32 micrograms/m3. Within the same community, daily concentrations of fine particulates varied by as much as eightfold, from 10 to 80 micrograms/m3, and were nearly identical within each pair of communities. Direct measurements of air quality and estimates based on a chemical mass balance receptor model showed that incinerator emissions did not have a major or even a modest impact on routinely monitored air pollutants. A onetime baseline descriptive survey (n = 6963) did not reveal consistent community differences in the prevalence of chronic or acute respiratory symptoms between incinerator and comparison communities, nor did we see a difference in baseline lung function tests or in the average peak expiratory flow rate measured over a period of 35 days. Based on this analysis of the first year of our study, we conclude that we have no evidence to reject the null hypothesis of no acute or chronic respiratory effects associated with residence in any of the three incinerator communities.

Adolescent↗
PubMedDate not supplied

Is breast self-examination predicted by knowledge, attitudes, beliefs, or sociodemographic characteristics?

The relationship of women's sociodemographic characteristics, knowledge, attitudes, and beliefs to breast self-examination (BSE) practice is not clear. We therefore studied these variables among older women at risk for developing breast cancer to determine which might be associated with the sensitivity, specificity, and frequency of BSE practice. We interviewed 300 women 40 to 68 years of age and measured BSE sensitivity and specificity using manufactured silicone breast models containing lumps. Of 54 variables and 10 scales examined univariately, six were associated with BSE sensitivity, one was negatively associated with specificity, and 10 were associated with frequency. No variable was associated with more than one component of BSE practice, and BSE frequency was not associated with BSE sensitivity or specificity. Using multivariate analysis, BSE sensitivity was best explained by type of employment, health interest, and perceived vulnerability to breast cancer, which accounted for approximately 16% of the variance. BSE frequency was best explained by intention to perform BSE, knowing how to perform BSE, using the correct method of BSE, self-confidence in the ability to perform BSE monthly, and self-confidence in the ability to find small lumps. These variables accounted for 27% of the variance. Sociodemographic characteristics, knowledge, attitudes, and beliefs poorly predicted how accurately women practiced BSE but somewhat better predicted how often women practiced BSE.

Adult↗