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S R Cole

Publications and source records attributed to S R Cole.

At least 19 recordsLinked to original sources

Analysis of complex survey data using SAS.

Commonly used statistical methods and software packages typically assume that observations are independent and identically distributed and fail to account for complex sampling designs when present. I suggest an approach to analyzing complex survey data in SAS, using weighted generalized estimating equations. Limited Monte Carlo simulations support the method. An example demonstrates application of the method and compares results to those from software commonly used in the analysis of complex survey data.

Aged↗

Interaction between HLA-DR2 and abnormal brain MRI in optic neuritis and early MS. Optic Neuritis Study Group.

The association of the human leukocyte antigen (HLA)-DR2 allele with brain MRI signal abnormalities and with the development of MS was assessed in 178 patients enrolled in the Optic Neuritis Treatment Trial. HLA haplotype DR2 was present in 85 (48%) of the 178 patients. Its presence was associated with increased odds of probable or definite MS at 5 years (odds ratio, 1.92; 95% confidence interval, 1.01 to 3.67; p = 0.04). The association was most apparent among patients with signal abnormalities on baseline brain MRI.

Administration, Oral↗

Test of item-response bias in the CES-D scale. experience from the New Haven EPESE study.

We present results of item-response bias analyses of the exogenous variables age, gender, and race for all items from the Center for Epidemiologic Studies Depression (CES-D) scale using data (N = 2340) from the New Haven component of the Established Populations for Epidemiologic Studies of the Elderly (EPESE). The proportional odds of blacks responding higher on the CES-D items "people are unfriendly" and "people dislike me" were 2.29 (95% confidence interval: 1.74, 3.02) and 2.96 (95% confidence interval: 2.15, 4.07) times that of whites matched on overall depressive symptoms, respectively. In addition, the proportional odds of women responding higher on the CES-D item "crying spells" were 2.14 (95% confidence interval: 1.60, 2.82) times that of men matched on overall depressive symptoms. Our data indicate the CES-D would have greater validity among this diverse group of older men and women after removal of the crying item and two interpersonal items.

Black or African American↗

Fruit and vegetable intake and risk of cardiovascular disease: the Women's Health Study.

BACKGROUND: Prospective data relating fruit and vegetable intake to cardiovascular disease (CVD) risk are sparse, particularly for women. OBJECTIVE: In a large, prospective cohort of women, we examined the hypothesis that higher fruit and vegetable intake reduces CVD risk. DESIGN: In 1993 we assessed fruit and vegetable intake among 39876 female health professionals with no previous history of CVD or cancer by use of a detailed food-frequency questionnaire. We subsequently followed these women for an average of 5 y for incidence of nonfatal myocardial infarction (MI), stroke, percutaneous transluminal coronary angioplasty, coronary artery bypass graft, or death due to CVD. RESULTS: During 195647 person-years of follow-up, we documented 418 incident cases of CVD including 126 MIs. After adjustment for age, randomized treatment status, and smoking, we observed a significant inverse association between fruit and vegetable intake and CVD risk. For increasing quintiles of total fruit and vegetable intake (median servings/d: 2. 6, 4.1, 5.5, 7.1, and 10.2), the corresponding relative risks (RRs) were 1.0 (reference), 0.78, 0.72, 0.68, and 0.68 (95% CI comparing the 2 extreme quintiles: 0.51, 0.92; P: for trend = 0.01). An inverse, though not statistically significant, trend remained after additional adjustment for other known CVD risk factors, with RRs of 1.0, 0.75, 0.83, 0.80, and 0.85 (95% CI for extreme quintiles: 0.61, 1.17). After excluding participants with a self-reported history of diabetes, hypertension, or high cholesterol at baseline, the multivariate-adjusted RR was 0.45 when extreme quintiles were compared (95% CI: 0.22, 0.91; P: for trend = 0.09). Higher fruit and vegetable intake was also associated with a lower risk of MI, with an adjusted RR of 0.62 for extreme quintiles (95% CI: 0.37, 1.04; P: for trend = 0.07). CONCLUSION: These data suggest that higher intake of fruit and vegetables may be protective against CVD and support current dietary guidelines to increase fruit and vegetable intake.

Age Factors↗

Effects of mutant c-kit in early myeloid cells.

Activating mutations in c-Kit, the receptor for Stem Cell Factor (SCF), have been identified in dysplasias and leukaemias of the mast cell lineage and have been shown to contribute to transformation in model systems. Early myeloid cells also normally express c-Kit and their survival, proliferation and differentiation is promoted by SCF. It might therefore be expected that c-Kit mutations could also be involved in some acute and/or chronic myeloid leukaemias. We have found that mutant c-Kit (and normal c-Kit in the presence of SCF) provides a strong differentiation stimulus in normal and immortalised murine early myeloid cells. Since maturation of haemopoietic cells, with the exception of mast cells, results in down-regulation of c-Kit expression, the transforming effects of mutant receptor may be self-limiting in most lineages. This is consistent with the observation that multipotential progenitor cells from some patients with systemic mastocytosis express mutant c-Kit. However, c-Kit mutations have been observed in a few cases of myelodysplastic syndromes or AML without mast cell features. Oncogenesis involves multiple genetic changes and the phenotype of malignant haemopoietic cells expressing mutant c-Kit may be influenced by co-oncogenic events. For example mutations blocking the differentiative effect of mutant c-Kit might result in AML rather than mastocytosis. Thus the extent to which c-Kit mutations contribute to malignancies of early myeloid phenotype remains unknown, and resolution of this issue is complicated by the heterogeneity of this family of diseases.

Animals↗

Amyloid goiter with parathyroid involvement: a case report and review of the literature.

Although involvement of the thyroid gland by amyloid is a relatively common phenomenon, diffuse enlargement of the gland secondary to infiltration by amyloid is infrequent. We report the pathologic findings in a case of primary amyloid goiter with involvement of a parathyroid gland in an euthyroid patient who presented to his physician with an enlarged thyroid, upper airway obstructive symptoms, and dysphagia. The clinical features of amyloid goiter, including difficulties in preoperative diagnosis and management, are discussed.

Adult↗

The National Eye Institute Visual Function Questionnaire: experience of the ONTT. Optic Neuritis Treatment Trial.

PURPOSE: To describe the health-related quality of life, measured with the National Eye Institute Visual Function Questionnaire (NEI-VFQ), of patients several years after the onset of optic neuritis, according to their neurologic and visual status; to assess the relationship between the NEI-VFQ subscales and clinical measures of visual function; and to assess the internal consistency reliability of the NEI-VFQ subscales. METHODS: The NEI-VFQ was administered to 244 patients 5 to 8 years after treatment for an episode of acute optic neuritis as part of the Optic Neuritis Treatment Trial. Visual acuity, visual field, contrast sensitivity, and color vision were measured at the same time as questionnaire completion. RESULTS: The NEI-VFQ scores generally were lower than those reported for a disease-free group. Reported dysfunction was greater when multiple sclerosis was present and when visual acuity was abnormal, supporting the construct validity of the NEI-VFQ. Rank correlations between the NEI-VFQ subscales and clinical measures of visual function were moderate at best. Internal consistency reliability was generally high for most of the NEI-VFQ subscales. CONCLUSIONS: These findings add support to the use of the NEI-VFQ as a valuable measure of self-reported visual impairment.

Acute Disease↗

Sense of exhaustion and coronary heart disease among college alumni.

Vital exhaustion, defined as a combination of fatigue, lack of energy, feelings of hopelessness, loss of libido, and increased irritability, has been proposed as a risk indicator for the development of coronary heart disease (CHD). It is unclear if the association between vital exhaustion and CHD is independent of sleep behavior, depression, and physical activity. We ascertained sense of exhaustion among 5,053 male college alumni who were free of cardiovascular disease, cancer, and chronic obstructive pulmonary disease by asking, "How often do you experience sense of exhaustion (except after exercise)?" on a health survey in 1980. Eight hundred fifteen men died during 12 years of follow-up, 25% due to CHD. After adjustment for age, body mass index, smoking status, and history of physician-diagnosed diabetes and hypertension, frequent sense of exhaustion was associated with a twofold increase in CHD mortality (rate ratio 2.07; 95% confidence interval 1.08 to 3.96). After additional adjustment for insomnia, sleep duration, use of sleeping pills and tranquilizers, physical activity, history of physician-diagnosed depression, and alcohol intake, the rate ratio was not appreciably altered; however, the association now was of borderline significance (rate ratio 2.06; 95% confidence interval: 0.98 to 4.36) because there were only 10 deaths from CHD among men who were frequently exhausted. In a prospective observational study, frequent sense of exhaustion appeared to be independently associated with increased risk of CHD mortality in men.

Adult↗

Insomnia and heart disease: a review of epidemiologic studies.

Since the discovery and successful treatment of sleep apnea, researchers seem to believe that the association between sleep disturbance and coronary heart disease (CHD) has been explained. To determine whether subjective nighttime sleep complaints (trouble sleeping, trouble falling asleep, trouble staying asleep), exclusive of apnea, predicted myocardial infarction and other coronary events, a MEDLINE search was conducted for articles published between January 1976 through August 1997. Ten studies with an explicit measure of association between an insomniac complaint and CHD were identified. Reported risk ratios for various sleep complaints and CHD events ranged from 1.0 for waking too early and CHD death in an elderly North Carolina community to 8.0 for the highest versus lowest quintile of a sleep scale in Finnish men. Higher quality studies showed risk ratios of 1.47-3.90 between trouble falling asleep and coronary events after adjusting for age and various coronary risk factors (combined effect=1.7, p<0.0001). While alternative explanations such as medication use still need to be ruled out, we theorize that a subjective insomniac complaint either may be part of a larger syndrome that includes poor health and depression, or it may be related to continual stressors, reduced slow-wave sleep, and autonomic dysfunction, which increase the risk of heart problems.

Confounding Factors, Epidemiologic↗

Simple bootstrap statistical inference using the SAS system.

Nonparametric bootstrap statistical inference is a robust computer intensive method for generating estimates of statistical variability for which formulae are not known or asymptotic assumptions are not met. A SAS macro that implements simple nonparametric bootstrap statistical inference is presented with an example. The program code is easily generalized to any SAS procedure which includes a BY statement, and to cases of clustered data.

Data Interpretation, Statistical↗

Effects of mutant c-Kit in early myeloid cells.

Activating mutations in c-Kit, the receptor for Stem Cell Factor (SCF), have been identified in dysplasias and leukaemias of the mast cell lineage and have been shown to contribute to transformation in model systems. Early myeloid cells also normally express c-Kit and their survival, proliferation and differentiation is promoted by SCE It might therefore be expected that c-Kit mutations could also be involved in some acute and/or chronic myeloid leukaemias. We have found that mutant c-Kit (and normal c-Kit in the presence of SCF) provides a strong differentiation stimulus in normal and immortalised murine early myeloid cells. Since maturation of haemopoietic cells, with the exception of mast cells, results in down-regulation of c-Kit expression, the transforming effects of mutant receptor may be self-limiting in most lineages. This is consistent with the observation that multipotential progenitor cells from some patients with systemic mastocytosis express mutant c-Kit. However, c-Kit mutations have been observed in a few cases of myelodysplastic syndromes or AML without mast cell features. Oncogenesis involves multiple genetic changes and the phenotype of malignant haemopoietic cells expressing mutant c-Kit may be influenced by co-oncogenic events. For example mutations blocking the differentiative effect of mutant c-Kit might result in AML rather than mastocytosis. Thus the extent to which c-Kit mutations contribute to malignancies of early myeloid phenotype remains unknown, and resolution of this issue is complicated by the heterogeneity of this family of diseases.

Acute Disease↗

Hypersensitivity pneumonitis: a sentinel event investigation in a wet building.

Hypersensitivity pneumonitis (HP) as a sentinel event implies a remediable exposure and an exposed cohort that require evaluation. A patient with HP convincingly related to her building led to a questionnaire survey in follow-up. Building coworkers demonstrated substantially higher symptom rates than did controls in five other buildings, although no further cases of disease were identified. It is likely that moisture sources in the building included an oversized cooling system and below-grade moisture, but the building met all applicable regulations and standards. Screening investigations for disease are not mandated by law and are often not conducted, in part because cost coverage is unclear. The absence of regulatory or professional standards that adequately address moisture in the built environment forces occupational health professionals to rely on disease documentation strategies to justify intervention.

Alveolitis, Extrinsic Allergic↗

Are sleep complaints an independent risk factor for myocardial infarction?

PURPOSE: To investigate whether subjective sleep complaints are an independent predictor of myocardial infarction (MI) in a community of older adults and to gain clues as to why the association between sleep complaints and incident MI exists. METHODS: Using longitudinal data from the Piedmont study on 2960 adults aged 65 or older who were free of symptomatic heart disease at baseline, we screened 19 potential confounders to determine if any, alone or in combination, could explain the observed relationship between incident MI and sleep complaints. RESULTS: During the three-year follow-up period, there were 152 incident MIs. Restless sleep (incidence density ratio (IDR) = 1.58, 95% confidence interval (CI) = 1.11, 2.24) and trouble falling asleep (IDR = 1.68, 95% CI = 1.09, 2.60) predicted incident MI after adjusting for age, gender, and race. IDRs were not substantially impacted by controlling for smoking, blood pressure, diabetes or obesity. After adjustment for education, number of prescription medicines, self-rated health, and depression score, all IDRs were nullified. In particular, self-rated health and depression were strong independent risk factors for MI. CONCLUSIONS: A subjective sleep complaint increases the likelihood of a first MI in older adults without overt coronary heart disease (CHD) independently of classic coronary risk factors and appears to be a marker for a syndrome of depression and malaise that may have a causal relationship to MI.

Aged↗

The predictive value of CSF oligoclonal banding for MS 5 years after optic neuritis. Optic Neuritis Study Group.

The predictive value of CSF oligoclonal banding for the development of clinically definite MS (CDMS) within 5 years after optic neuritis was assessed in 76 patients enrolled in the Optic Neuritis Treatment Trial. The presence of oligoclonal bands was associated with the development of CDMS (p = 0.02). However, the results suggest that CSF analysis is only useful in the risk assessment of optic neuritis patients when brain MRI is normal and is not of predictive value when brain MRI lesions are present at the time of optic neuritis.

Adolescent↗