Biomedical subjects

F Gilliland

Publications and source records attributed to F Gilliland.

8 recordsLinked to original sources

PubMed2000

Association between air pollution and lung function growth in southern California children.

Average growth of lung function over a 4-yr period, in three cohorts of southern California children who were in the fourth, seventh, or tenth grade in 1993, was modeled as a function of average exposure to ambient air pollutants. In the fourth-grade cohort, significant deficits in growth of lung function (FEV(1), FVC, maximal midexpiratory flow [MMEF], and FEF(75)) were associated with exposure to particles with aerodynamic diameter less than 10 micrometer (PM(10)), PM(2.5), PM(10)-PM(2.5), NO(2), and inorganic acid vapor (p < 0.05). No significant associations were observed with ozone. The estimated growth rate for children in the most polluted of the communities as compared with the least polluted was predicted to result in a cumulative reduction of 3.4% in FEV(1) and 5.0% in MMEF over the 4-yr study period. The estimated deficits were generally larger for children spending more time outdoors. In the seventh- and tenth-grade cohorts, the estimated pollutant effects were also negative for most lung function measures, but sample sizes were lower in these groups and none achieved statistical significance. The results suggest that significant negative effects on lung function growth in children occur at current ambient concentrations of particles, NO(2), and inorganic acid vapor.

Adolescent↗

PubMed2000

Sex-specific effects of asthma on pulmonary function in children.

To evaluate the effects on lung function of asthma, time since diagnosis of asthma, and age at diagnosis of asthma, we examined school children in a cohort of 2,277 fourth- and seventh-graders at least twice during a 4-yr follow-up period. Sex-specific models for each lung function were fitted through mixed-effects models that used regression splines and captured age-dependent trends in the effect of asthma on lung function. In males, a history of asthma was associated with large and statistically significant deficits in maximum midexpiratory flow (MMEF) (-4.89%) and forced expiratory flow at 75% of expired FVC (FEF(75)) (-6.62%), whereas in females these deficits were smaller (-1.93% and -2.45%, respectively) and were not statistically significant. However, larger deficits were seen in both males and females with longer time since diagnosis. In males with more than 6 yr since diagnosis, there were significant deficits in FEV(1) (-3.91%), MMEF (-7.39%), FEF(75) (-8.12%), and peak expiratory flow rate (PEFR) (-4.65%) as compared with children with less than 3 yr since diagnosis. There were fewer females with more than 6 yr since diagnosis, but deficits were similar to those of males for FEV(1) (-2.52%), MMEF (-9.26%), and FEF(75) (-14.28%). Large deficits in flow rates in both large and small airways were observed in males and females for whom asthma was reported to have been diagnosed before age 3 yr. There was little evidence that lung growth in children with asthma "catches up" at older ages. Therefore, because a constant percent deficit in lung function implies an increasingly large absolute deficit in older children with larger lungs, these results are consistent with prior evidence that lung function deficits in children with asthma persist into adulthood. We also suggest that in children, commonly observed differences between sexes in the impact of asthma on lung function may reflect differences in the duration and age of onset of asthma in males and females.

Age of Onset↗

PubMed2000

Patient and tumor characteristics of colon cancers with microsatellite instability: a population-based study.

Molecular screening for microsatellite instability (MSI) in colon cancers has been proposed to identify individuals with hereditary nonpolyposis colorectal cancer. To date, most reports of MSI in colorectal cancer have been based on studies of clinical case series or high-risk families. We examined the proportion of incident colon cancers in the general population that exhibit MSI by patient and tumor characteristics. We interviewed 201 colon cancer cases ascertained by the New Mexico Tumor Registry in the metropolitan Albuquerque area for demographic information, lifestyle factors, medical history, and family cancer history. Paired normal and tumor tissue specimens were obtained for each case. Three microsatellite markers were used; instability was defined as observed alteration at two or more loci. Overall, 37 of 201 (18%) colon cancers exhibited instability. MSI was more common among cases >70 years (26%) and most common among cases >80 years (38%). MSI was significantly associated with tumors in the proximal colon and with later stage and poor differentiation among cases >70 years. MSI was not associated with a history of polyps. Family history of colorectal cancer was associated with MSI only among cases <50 years. When all factors were analyzed jointly in a regression model, proximal subsite and poor differentiation remained significantly associated with MSI. One patient, whose tumor exhibited MSI, fulfilled the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer. Our study provides a population-based estimate of MSI in colon tumors and a representative estimate of the proportion of colorectal cancer patients in the general population who consent to be interviewed for family cancer history and to have biological samples analyzed.

Adult↗

PubMed1999

Air pollution and bronchitic symptoms in Southern California children with asthma.

The association of air pollution with the prevalence of chronic lower respiratory tract symptoms among children with a history of asthma or related symptoms was examined in a cross-sectional study. Parents of a total of 3,676 fourth, seventh, and tenth graders from classrooms in 12 communities in Southern California completed questionnaires that characterized the children's histories of respiratory illness and associated risk factors. The prevalences of bronchitis, chronic phlegm, and chronic cough were investigated among children with a history of asthma, wheeze without diagnosed asthma, and neither wheeze nor asthma. Average ambient annual exposure to ozone, particulate matter (PM(10) and PM(2.5); [less than/equal to] 10 microm and < 2.5 microm in aerodynamic diameter, respectively), acid vapor, and nitrogen dioxide (NO(2)) was estimated from monitoring stations in each community. Positive associations between air pollution and bronchitis and phlegm were observed only among children with asthma. As PM(10) increased across communities, there was a corresponding increase in the risk per interquartile range of bronchitis [odds ratio (OR) 1.4/19 microg/m(3); 95% confidence interval (CI), 1.1-1.8). Increased prevalence of phlegm was significantly associated with increasing exposure to all ambient pollutants except ozone. The strongest association was for NO(2), based on relative risk per interquartile range in the 12 communities (OR 2.7/24 ppb; CI, 1.4-5.3). The results suggest that children with a prior diagnosis of asthma are more likely to develop persistent lower respiratory tract symptoms when exposed to air pollution in Southern California.

Adolescent↗

PubMed1999

Association between outcome and telomere DNA content in prostate cancer.

PURPOSE: To perform an initial retrospective investigation of the relationship between outcome in patients with organ confined prostate adenocarcinoma and the tumor cells' content of telomere DNA. MATERIALS AND METHODS: The case-controlled study group was composed of eighteen men diagnosed with prostatic adenocarcinoma prior to 1993. The group was selected so that approximately one half died within ten years of diagnosis and one half survived ten years or longer. Archival, paraffin-embedded tumor tissue was recovered for each patient. DNA was extracted from newly cut sections, fixed to nylon membranes and hybridized with P32-labeled centromere- and telomere-specific probes. Telomere DNA contents were quantitated from the hybridized radioactivities. The relationships between telomere DNA content and survival, and telomere DNA content and disease recurrence in men receiving prostatectomies were determined. RESULTS: Death and disease recurrence were associated with reduced telomere DNA content (p <0.0001, p <0.0001, respectively). CONCLUSIONS: Telomere DNA content may differentiate high-risk patients with metastatic prostate cancer from men with indolent disease who can be spared the unnecessary side effects and expense of treatment by management with "watchful waiting."

Adenocarcinoma↗

PubMed1998

Prostate-specific antigen testing practices and outcomes.

OBJECTIVES: To characterize prostate-specific antigen (PSA) testing practices in a hospital-based primary care clinic, and to determine the outcomes of PSA testing, including urology referrals, biopsies, cancers detected, and cancer treatments. DESIGN: Retrospective cohort study. Data were obtained from computerized Department of Veterans Affairs (VA) files and the statewide New Mexico Surveillance, Epidemiology, and End Results (SEER) tumor registry. SETTING: Primary care clinics in a university-affiliated VA Medical Center. PATIENTS: Subjects were 1,448 men without cancer undergoing PSA testing in 1993 with follow-up through 1994. MAIN RESULTS: Twenty-one percent of clinic enrollees at least 40 years of age were tested with PSA, including 58 who were 75 years of age or older. By the end of 1994, 40.0% (95% confidence interval [CI] 37.2%, 42.8%) were retested; 25.6% (95% CI 21.7%, 29.5%) of initial retesting occurred within 6 months. Overall, 20.7% (95% CI 18.9%, 22.5%) of PSA tests in the cohort were for men aged 75 years or older and were repeated within 6 months. Among the 193 subjects with PSA values > or = 4.0 ng/mL, 86.0% (95% CI 81.1%, 90.9%) were followed-up in urology clinic, and 46.1% (95% CI 39.1%, 53.1%) underwent biopsy. Only 11 of 51 men aged 75 years or older who were referred to urologists for an elevated PSA underwent biopsy. Forty cancers were diagnosed-a detection rate of 2.8% (95% CI 2.0%, 3.6%). Of these, 28 were organ-confined, 7 had regional invasion, and 3 had distant metastases. CONCLUSIONS: Primary care providers frequently ordered PSA tests, but a substantial proportion of testing occurred outside recommended age ranges and screening intervals. Older patients with elevated PSA values often did not complete diagnostic workups. Better adherence to screening guidelines may limit the number of both PSA tests and urology referrals.

Adult↗

PubMed1996

Breast cancer survival among New Mexico Hispanic, American Indian, and non-Hispanic white women (1973-1992).

A study of breast cancer survival was conducted among New Mexico Hispanic and non-Hispanic white women and New Mexico and Arizona American Indian women diagnosed between 1973 and 1992. The goals were to determine whether, after adjusting for first treatment and the extent of disease at diagnosis, American Indian and Hispanic women had poorer survival than non-Hispanic whites and, if survival had improved over time, whether comparable improvements had been made for the three racial/ethnic groups. Five-year relative survival rates were calculated, and a Cox proportional hazards model was constructed to compare survival between races/ethnicities, adjusting for first treatment and the extent of disease at diagnosis. Findings indicate that during 1983-1992, breast cancer was more commonly detected at a local stage for all three groups compared to 1973-1982. Five-year relative survival improved for non-Hispanic white and American Indian women with local or regional disease, but the improvement was statistically significant only for non-Hispanic white women and for American Indian women with local disease. Despite earlier stages at diagnosis, Hispanic females showed less improvement in overall or stage-specific survival than non-Hispanic whites. The Cox model indicated that American Indian women experienced poorer survival than non-Hispanic whites during both time periods. Survival of Hispanic women with breast cancer was comparable to non-Hispanic whites during 1973-1982 but was significantly worse during 1983-1992. The significance of this lower survival is amplified by increasing breast cancer incidence among New Mexico Hispanics and American Indians.

Breast Neoplasms↗

PubMed1994

Trends in prostate cancer incidence and mortality in New Mexico are consistent with an increase in effective screening.

The increasing occurrence of prostate cancer in the United States has led to recommendations for routine prostate cancer screening in men aged 50 years and older. Although present methods of prostate cancer screening have not been shown to reduce mortality, screening using digital rectal examination or prostate-specific antigen does detect tumors at earlier stages. To assess whether trends in incidence and mortality rates are consistent with an increase in effective screening in New Mexico, we examined prostate cancer incidence rates calculated from data collected by the New Mexico Tumor Registry for the years 1969-1991, and mortality rates calculated from data collected by the New Mexico Bureau of Vital Statistics for the years 1958-1991. Population-based measures of prostate cancer screening frequency in New Mexico are not available for the period of this study; however, the proportion of prostate cancers detected by screening, as documented by a review of records from a random sample of prostate cancer cases, increased 3-fold, from 13% during the 1969-1972 period to 41% in the 1988-1991 period. During the period of study, age-adjusted incidence rates increased from 66.3 to 122.3/100,000 men. Stage migration from distant to earlier stages was apparent in the increase in the proportion of early stage cancers from 77.5 to 85.5%, and the decrease of distant stage cancers from 21.2 to 9.8%. Stage-specific incidence rates increased for local (87.3%) and regional stage cancers (283.0%), and decreased for distant stage cancers (16.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗