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Biomedical subjects

R Y Demers

Publications and source records attributed to R Y Demers.

At least 37 records · Page 2Linked to original sources
PubMed1991

Lymphocytopenia, T-lymphocyte subsets, and colorectal polyps in automotive pattern and model makers.

Several studies have found pattern and model makers to be at increased risk for colorectal polyps and colorectal cancers. One study found an increased prevalence of lymphocytopenia. The association of total lymphocyte, CD4 (T-helper cell), CD8 (T-suppressor cell), CD2 (total T-cell), and CD16 (natural killer cell) counts with biopsy-proved colorectal polyp status was investigated in 70 patternmakers participating in one or more of four sequential screenings. In logistic regression analyses after adjusting for age or trade years, pack-years smoked, and material worked with most, a history of any type of polyp was significantly associated with total lymphocyte count (odds ratio of 2.01 for a 500 cell/cc decrease, P = 0.03), and somewhat associated with decreased CD4 and CD2 counts (P values of 0.06 and 0.07, respectively). In linear regression models adjusted for age, pattern and model makers had (regardless of polyp status) significantly lower CD4, CD8, CD2, and CD16 counts than did laboratory reference controls (P value less than 0.01 for each comparison). These findings appear consistent with a sequence of carcinogenesis initiated by pattern and model makers' work-place exposures that depress immune surveillance thus promoting the development of colorectal polyps as a precursor of carcinoma.

Adenocarcinoma↗
PubMed1990

Respiratory morbidity of pattern and model makers exposed to wood, plastic, and metal products.

Pattern and model makers are skilled tradespersons who may be exposed to hardwoods, softwoods, phenol-formaldehyde resin-impregnated woods, epoxy and polyester/styrene resin systems, and welding and metal-casting fumes. The relationship of respiratory symptoms (wheezing, chronic bronchitis, dyspnea) and pulmonary function (FVC% predicted, FEV1% predicted, FEV1/FVC% predicted) with interview-derived cumulative exposure estimates to specific workplace agents and to all work with wood, plastic, or metal products was investigated in 751 pattern and model makers in southeast Michigan. In stratified analyses and age- and smoking-adjusted linear and logistic regression models, measures of cumulative wood exposures were associated with decrements in pulmonary function and dyspnea, but not with other symptoms. In similar analyses, measures of cumulative plastic exposures were associated with wheezing, chronic bronchitis, and dyspnea, but not with decrements in pulmonary function. Prior studies of exposure levels among pattern and model makers and of respiratory health effects of specific agents among other occupational groups support the plausibility of wood-related effects more strongly than that of plastic-related effects.

Adult↗
PubMed1990

Asbestos-related pulmonary disease in boilermakers.

Boilermakers are skilled building tradesmen who construct, repair, and dismantle boilers. The present study reports on the evaluation of members of a Michigan boilermaker's union for the presence of signs and symptoms of chronic pulmonary disease. Study variables included standardized evaluations of chest x-ray findings, pulmonary function testing, physical examination, and respiratory symptoms. An overall participation rate of 69% was achieved. A non-participant survey identified no significant differences between participants and non-participants in dyspnea, cough, age, or smoking history. Among participants with greater than 20 years experience in the trade, the mean FVC was 91% of predicted; the FEV1 was 86% of predicted; 25% showed at least a 1/0 profusion of interstitial markings on chest x-ray; 30% had bilateral pleural abnormalities; and 52% had audible inspiratory rales on physical examination. Forced vital capacity and forced expiratory volume at one second both decreased with years in the trade. Chest x-ray findings of interstitial fibrosis and pleural plaques were related to ten or more years in the trade, as were respiratory symptoms of pulmonary rales, wheeze, and dyspnea.

Age Factors↗
PubMed1990

Incongruence between self-reported symptoms and objective evidence of respiratory disease among construction workers.

In clinical settings, self-reported symptoms and objective evidence of disease may be poorly correlated. In the present study, symptoms and objective evidence of pulmonary disease were compared in a community sample of construction workers with occupational exposure to asbestos. Symptoms of dyspnea and cough were assessed by a standardized questionnaire. The clinical examination included a chest X-ray, pulmonary function testing (PFT), and a physical examination. Both symptoms and objective clinical findings were strongly related to years in these trades. However, less than 1% of workers reported symptoms in the absence of any clinical evidence of disease. A similar low percentage of workers denied any symptoms yet produced clear evidence of pulmonary disease on clinical examination. Results were interpreted in terms of the variety of factors which have been associated with patients' readiness, and conversely, reluctance to report symptoms. The comparatively low frequency of incongruence between symptoms and objective clinical findings in this study suggests over emphasis of malingering by other authors. Health care might be improved if more attention is given by clinicians and researchers to patients who fail to report symptoms in the presence of disease.

Adult↗
PubMed1990

The impact of physicians' brief smoking cessation counseling: a MIRNET study.

Although many family physicians may discuss smoking cessation with their patients, few do so consistently. A common belief among many physicians is that such efforts will not deter their patients from smoking. Others believe the time commitment required for a successful intervention is excessive. The present study addressed the above issues by examining the effect of a 3- to 5-minute unstructured physician discussion encouraging smoking cessation with family practice patients. Cigarette-smoking patients of two busy family practices in southeast Michigan were randomly assigned to either a control group receiving routine care or an intervention group receiving, in addition to routine care, smoking cessation counseling from their physician. A third comparison group was drawn from smokers in practices not involved in delivering the intervention. Two hundred thirty-eight patients from the intervention group, 178 from the control group, and 47 from the comparison group were followed up with a telephone interview at 6 months. Intervention group patients made significantly more quit attempts than did those in the control group (P less than .001), which was similar to the comparison group. At the 6-month follow-up, 8% of intervention group members, and 4% of both the comparison and control groups reportedly were abstinent from smoking. Among those contacted at the 1-year follow-up, the respective percentages abstinent were 8%, 3%, and 4%. Although these differences in quit rates were not statistically significant, the findings suggest that physicians can positively affect patient smoking cessation. This intervention was feasible in busy family practices, highlighting its generalizability and applicability to other family practice settings in the United States.

Adult↗
PubMed1990

Termination of health benefits for Pittston mine workers: impact on the health and security of miners and their families.

Mine workers represented by the United Mine Workers of America (UMWA) have had comprehensive medical care coverage since 1950. On February 1, 1988, UMWA employees of the Pittston Coal Group had their health care benefits abruptly terminated. Renewal of these benefits became a major reason for the subsequent UMWA strike against Pittston. In December, 1989, physician interviewers were organized to document the human experience of this termination of health care benefits. This report summarizes these interviews, and concludes that the UMWA experience in the Pittston coal fields is one example of the barriers to health care experienced by an increasing proportion of the United States population.

Adolescent↗
PubMed1990

Pathologist agreement in the interpretation of colorectal polyps.

Practicing physicians commonly perform flexible sigmoidoscopy in their offices. Polyploid lesions are frequently biopsied and sent to community hospitals for pathological interpretation. The pathologist's opinion often determines the course of medical follow-up for the patient, especially in cases in which early malignancy is suspected. This paper addresses the agreement of community-based pathologists regarding the interpretation of colorectal polyp pathology. Ten pathological slide sections were sent to 22 different community-based pathologists in southeast Michigan. These pathologists were asked to record their diagnosis of the specific histologies represented in each of the slides. The results indicated a high level of agreement of histologies in the dichotomous categories of hyperplasia versus adenoma. However, there was considerable disagreement on the presence of moderate or severe atypia. The results of this study indicate that clinicians performing biopsies on patients at risk for colorectal cancer should be aware of the potential for diagnostic variability among pathologists, and should plan follow-up strategies which may include seeking second pathological opinions when a significant patient management decision must be made.

Adenoma↗
PubMed1989

Glycosylated hemoglobin levels and self-reported stress in adults with diabetes.

This study examined the relationship between glycosylated hemoglobin and self-reported stress in a sample of adult Type II diabetics. The study sample was drawn from participants in a randomized clinical trial of the comparative effectiveness of two oral antihyperglycemic drugs in the treatment of non-insulin-dependent diabetes. The 19 study participants were asked to complete a brief questionnaire on recent stress. Stress scores were then compared with levels of glycosylated hemoglobin. Correlations between glycosylated hemoglobin and stress scores were highly significant, a finding of particular clinical relevance in view of the relatively small number of participants. These findings suggest that sustained stress may contribute to poor glucose control in diabetics. Individuals interested in stress-related research may find glycosylated hemoglobin a useful marker of physiological stress.

Adult↗
PubMed1989

Compliance with colorectal cancer screening in a high-risk occupational group.

A Detroit-area union offers an early detection colorectal cancer screening program consistent with that recommended by the American Cancer Society. Analyses compared men who have complied with the American Cancer Society recommendations with men who have not so complied. Older men, nonsmokers, and woodworkers were most likely to participate in all screening examinations. Primary reasons for nonparticipation were the belief that the examination was unnecessary, anxiety/affective concerns; and time/motivation problems. Particularly important to the success of such programs is a sensitive health education component to address personal concerns related to the procedure, and also the dissemination of information about the efficacy of the examination for early detection of colorectal cancer.

Adult↗
PubMed1988

Serum cholesterol and colorectal polyps.

Colorectal cancer and hypocholesterolemia have recently been associated, and colorectal polyps have a known relationship with colorectal cancer. In order to establish further evidence regarding the nature of the serum cholesterol-colorectal cancer relationship, this study investigated the hypothesis that men with colorectal polyps would have lower serum cholesterol levels than men without polyps. Of the 1380 men screened by sigmoidoscopy for colorectal polyps, 246 had at least one polyp. The men with polyps were older than those without, and also had higher cholesterol levels, but after controlling for age, there were no serum cholesterol differences. These data suggest that low serum cholesterol is not etiologically linked to cancer. Analyses of potentially confounding variables showed smoking to be strongly related to the presence of polyps.

Adult↗
PubMed1987

Physician accuracy in diagnosing colorectal polyps.

Since the medical management of persons with adenomatous colorectal polyps differs from that of those with hyperplastic polyps, accuracy of diagnosis is essential. Although many physicians have grown confident that their skills of visual diagnosis are adequate, few data exist to support this confidence. In order to examine the accuracy of physicians' judgments regarding colorectal polyp histology, the visual diagnosis of physicians experienced in endoscopy was compared with the histologic report. Eighty-one polyps were discovered by flexible sigmoidoscopy among 718 participants in a colon cancer screening program. Eighty percent of all polyps were detected accurately. The diagnostic sensitivity of detecting adenomas was 69 percent, while specificity (accurate diagnosis of hyperplastic polyps) was 86 percent, and there were an additional eight false negative and eight false positive diagnoses. Further analyses revealed that there are individual patterns of diagnostic mistakes made by physicians and that mistakes frequently are related to polyp size. These findings are particularly important in light of the expanding numbers of relatively inexperienced primary care providers performing flexible sigmoidoscopy whose diagnoses may be strongly dependent on polyp size.

Adenoma↗
PubMed1985

Relative sensitivity of the fecal occult blood test and flexible sigmoidoscopy in detecting polyps.

A group of 1,002 male pattern and model makers, an occupational group at high risk for colorectal cancers, was screened for the presence of polyps and malignancies of the lower gastrointestinal tract. Flexible sigmoidoscopy and serial fecal occult blood testing were both performed on 988 of the participants, and 165 were found to have at least one colorectal polyp. Only 3% of all men with visualized polyps showed Hemoccult-positive stools. Only 2 (4%) of the 51 men with histologically proven adenomatous polyps were Hemoccult positive. Adenomatous polyps of 1 cm or greater in diameter are malignant 8% of the time. This study concludes that the fecal occult blood test sensitivity in detecting colorectal polyps is unacceptably low. It should be supplemented by more rigorous procedures, especially in populations at high risk for colorectal cancer.

Adolescent↗
PubMed1985

Prevalence of colorectal polyps among Michigan pattern and model makers.

A group of 902 pattern and model makers were screened for colorectal cancer and polyps using a 60-cm flexible sigmoidoscope. Three recent mortality studies have found a significant excess of colorectal malignant neoplasms in this occupational group. Four adenocarcinomas, two carcinoids, and two cancers in situ were found. In addition, 150 (17%) of the individuals were found to have polyps. Among white males 40 to 70 years of age, the prevalence rate was found to be 23%. The prevalence of colorectal polyps among the pattern and model makers was compared with that of four previously studied asymptomatic populations who were also examined using a 60-cm flexible sigmoidoscope. Polyp rates were found to be significantly greater among pattern and model makers than among three of the four comparison populations. The odds ratios between these three populations and the study population ranged from 1.9 to 2.7 and closely approximate the ratios found in previous studies evaluating colon cancer in this occupational group.

Adenocarcinoma↗
PubMed1985

Leptospiral exposure in Detroit rodent control workers.

Antibody levels to L. icterohemorrhagiae of rodent control workers and two control groups were compared with antibodies against five other leptospiral serotypes carried predominantly by species other than rats. Rodent control workers contact urban rats, 77 per cent of which are carriers of leptospiral organisms. Rodent control workers had higher antibody levels against L. icterohemorrhagiae than control groups (OR 4.37, 99 per cent CI = 3.0, 6.3 and OR 11.08, 99 per cent CI = 5.6, 22). Antibodies against the other five serotypes were almost non-existent in the study group.

Adult↗
PubMed1984

Mortality among pulp and paper workers.

Mortality among 2,113 U.S. and Canadian members of the Pulp, Sulfite, and Paper Workers' Union, 1935 through 1964, was studied using a proportionate mortality analysis. Mortality due to gastric cancer was found to be elevated in all jurisdictions, but only in mills using sulfate or sulfite pulping. An excess of mortality due to kidney cancer was limited to mills in Oregon and Washington. Excesses of deaths due to leukemia, Hodgkin's disease, and lymphosarcoma were observed only in mills in Oregon, Washington, and Wisconsin and the province of Quebec. Based on small numbers, excesses of deaths due to cancers of rectum, pancreas, kidney, and lymphosarcoma were seen primarily among sulfite process workers, while Hodgkin's disease deaths occurred primarily in sulfate (kraft) process workers. These findings suggest that cancer mortality in pulp and paper workers may be related both to pulping process and to tree species processed.

Canada↗