Search PubMed⌕ Search

Biomedical subjects

P Boyle

Publications and source records attributed to P Boyle.

At least 181 records · Page 10Linked to original sources
PubMed1996

Time trend and age-period-cohort effect on incidence of bladder cancer in Connecticut, 1935-1992.

Earlier studies indicated that the incidence rates for bladder cancers rose rapidly in both the United States and Europe. Tobacco smoking is considered to be the major risk factor for urinary bladder cancer, and recent studies from Connecticut show that several smoking-related cancers have started leveling off or decreasing. The time trend for bladder cancer, however, is not clear in Connecticut. The current study examined the long-term trend of bladder cancer in Connecticut. Our results show that urinary bladder cancer has been increasing, with a marked increase among males. The rate of increase, however, has slowed since the early 1980s. Birth-cohort examination shows that the rates have leveled off for those born after about 1935 in both males and females. Age-period-cohort modeling results also show that the birth-cohort patterns of bladder cancer are somewhat similar to those observed for lung cancer in Connecticut, thus supporting the findings from analytical epidemiologic studies which indicate that cigarette smoking is one of the major risk factors for urinary bladder cancer. Our results also suggest that the difference in environmental and occupational exposures between males and females may be responsible for the large difference in the incidence rate of bladder cancer seen between the sexes.

Adult↗
PubMed1996

Time trend and age-period-cohort effect on incidence of thyroid cancer in Connecticut, 1935-1992.

Recent studies from Europe suggest a continuing increase in thyroid cancer, but it is unclear whether this trend also applies to the United States. The current study examined the long-term trend of thyroid cancer in Connecticut. Our results show that the overall age-adjusted incidence rate of thyroid cancer has been increasing in Connecticut, from 1.30/100,000 in 1935-1939 to 5.78/100,000 in 1990-1992 in females, and from 0.30/100,000 in 1935-1939 to 2.77/100,000 in 1990-1992 in males. The increase mainly comes from papillary carcinoma of the thyroid. The birth cohort analyses indicate that the increase in thyroid cancer occurred among cohorts born between 1915 and 1945, which experienced an increase of 31.4% every 5 years in males and 17.3% in females over the period 1960-1979. For those born since the 1945 cohort, the incidence has been decreasing, at rates of 9.3% and 8.3% every 5 years over the period 1975-1992 in males and females, respectively. Age-period-cohort modeling results also suggest a strong birth cohort effect on the observed time trend in both sexes, which closely follows the introduction of radiation treatment of benign childhood conditions in the head and neck between 1920 and the 1950s in the United States. Our results are consistent with the suggested radiation hypothesis, indicating that radiation treatment of benign childhood conditions in the head and neck is largely responsible for the observed increase of thyroid cancer in Connecticut.

Adenocarcinoma, Follicular↗
PubMed1996

Cigarette smoking and pancreas cancer: a case control study of the search programme of the IARC.

A multi-centre case-control study of pancreas cancer, designed to be population-based, to use a random sample of local populations as controls and to use a common protocol and core questionnaire, was conducted as the first study of the SEARCH programme of the International Agency for Research on Cancer. "Ever-smokers" were found to be at increased risk for pancreas cancer compared with "never-smokers" consistently in all strata of gender, response status and centre. Risk of pancreas cancer was found to increase with increasing lifetime consumption of cigarettes, the relative risk rising to 2.70 (95% C.I. 1.95 to 3.74) in the highest intake category. The overall trend in risk was highly significant and the association was found consistently in each stratum of gender, response status and centre. Fifteen years had to pass from quitting cigarette smoking until the risk fell to a level compatible with that in never-smokers among the heaviest group of smokers; among the 2 lowest tertiles this happened within 5 years. Further, reported smoking habits more than 15 years before diagnosis appeared to have no influence on pancreas-cancer risk, irrespective of amount smoked. The results are consistent with a causal role for cigarette smoking in the aetiology of pancreas cancer and illustrate that ceasing to smoke cigarettes can lead to reductions in the elevated risk of pancreas cancer produced by this habit.

Case-Control Studies↗
PubMed1996

Cancer among patients on renal replacement therapy: a population-based survey in Lombardy, Italy.

Longer and better survival of End-Stage Renal Disease (ESRD) patients undergoing renal replacement therapy (RRT) is now associated with a higher prevalence of new elderly patients receiving renal replacement therapy (dialysis). In order to help clarify the association of cancer risk with RRT, the incidence of cancer in a population-based cohort of uraemic patients in the Region of Lombardy, northern Italy, was undertaken using data from the Lombardy Regional Dialysis and Renal Transplant Registry. A total of 479 cases of cancer of all sites was recorded in this population. There were statistically significantly elevated risks of primary liver cancer, kidney cancer, thyroid cancer, lymphoma and multiple myeloma. When the data were examined according to primary renal diseases, there did not appear to be any particular association between excess cancer risk and the underlying pathology. While some caution must be expressed in interpreting these data, due to the relatively small numbers of cases expected in many of the disease entities, the results indicate an excess of renal-cell and liver carcinomas and lymphomas in patients receiving RRT and highlight the necessity of careful follow-up and awareness of these associations, together with the need for early detection of such tumours.

Aged↗
PubMed1996

Continuing increase in incidence of germ-cell testis cancer in young adults: experience from Connecticut, USA, 1935-1992.

The current study is designed to examine long-term trends by histologic types of testis cancer in Connecticut. A regression model was used to identify age, period, or cohort as determinants of the time-trend on histologic types of testis cancer. The results from this descriptive epidemiologic study show that the overall age-adjusted incidence rate of testis cancer has increased 3.5-fold in Connecticut during the past nearly 60 years of cancer registration. The rates for seminoma and non-seminoma have been increasing since the mid-1950s and increase in a similar manner for those aged 15 to 49. The largest increase was observed in the age groups 20 to 44 for seminoma and 15 to 34 for non-seminoma. The observed increase was limited to whites. The results from age-period-cohort modeling suggest that the observed increase in seminoma before 1950s could be largely attributable to a period effect, while the increase for cohorts born after about 1910 both for seminoma and for non-seminoma are mainly explained by a strong birth-cohort effect. Therefore, the observed increase in germ-cell testis cancer in this population is likely to continue in the coming years. Thus far, the proposed hypotheses, such as exposure to DES in utero, earlier lifetime exposure to viruses, trauma or unusual amounts of heat to the testis, cannot adequately explain the observed incidence patterns of testis cancer. Analytical epidemiologic studies with large sample size are urgently needed to examine the risk factors responsible for the increase.

Adolescent↗
PubMed1996

Inhibition of nitric oxide with aminoguanidine reduces bacterial translocation after endotoxin challenge in vivo.

BACKGROUND: Administration of lipopolysaccharide (LPS) has been shown to increase bacterial translocation (BT) in vivo and in vitro. In addition, LPS upregulates inducible nitric oxide synthase expression in the intestinal epithelium-a phenomenon that can either enhance microbial killing, or alternatively, promote BT by impairing the gut barrier. OBJECTIVE: To determine the effect, if any, of an inhibitor of nitric oxide synthase, namely, aminoguanidine (AG), on BT after LPS challenge. DESIGN: Sprague-Dawley rats were randomized to receive either AG or normal saline solution via subcutaneously placed osmotic pumps (Alzet), followed 18 hours later by LPS injection (5 mg/kg or 20 mg/kg intraperitoneally). Quantitative cultures of the cecum, mesenteric lymph nodes, liver, and spleen were obtained, and plasma nitrite and nitrate levels were measured at 24 hours. Transmembrane potential difference and mucosal permeability to fluorescein isothiocyanate-labeled dextran and fluorescein isothiocyanate-labeled Escherichia coli C25 were measured in the Using chamber. The intestinal membrane was examined by light, transmission electron, and confocal laser microscopy. RESULTS: Rats that were given high-dose LPS had elevated levels of nitrite and nitrate and a 100% incidence of BT. In contrast, AG infusion significantly reduced both BT (22%) and nitrite and nitrate levels. Animals that received LPS and normal saline solution had a significantly lower transmembrane potential difference than those that received LPS and AG. High-dose LPS resulted in sloughing of the apical enterocytes at the villus tips where bacterial entry seemed to occur, as seen with confocal laser microscopy. CONCLUSIONS: Inhibition of nitric oxide production with AG decreases BT after high-dose LPS challenge. The mechanism may involve increased cellular viability and decreased damage to the gut mucosal barrier in rats that receive AG.

Animals↗
PubMed1996

Nutrition and oral cancer.

Epidemiologic evidence on the relationship between nutrition and oral cancer is reviewed. Ecologic and case-control studies provide most of the evidence regarding the nutritional epidemiology of oral cancer. The ecologic evidence is that the considerable geographic variation in the incidence of oral cancer is consistent with variation in nutrition. Because incipient oral cancer is likely to affect the diets of oral cancer patients, even before diagnosis, case-control studies are limited by their ability to extract comparable information from subjects regarding their pre-illness diets. The case-control evidence is that a diet that emphasizes fruit and vegetable intake may protect against oral cancer. However, this case-control evidence is not highly consistent; individual foods that appear protective in some studies do not in others, and the effects of diet appear to be modest when compared with those of smoking and alcohol consumption. The nutritional epidemiology of oral cancer is marked by two risk factors that appear far more powerful than nutrition: tobacco use and alcohol consumption. As these likely are related to nutrition, they pose as important potential confounders. Oral hygiene also may confound the association of nutrition and oral cancer risk; it is likely to be associated with dietary practice, and it has been shown to be related to oral cancer risk. Thus, studies of nutrition in the epidemiology of oral cancer also must address the effects of tobacco and alcohol consumption and oral hygiene.

Alcohol Drinking↗
PubMed1996

The relationship between sexual life and urinary condition in the French community.

As part of a large, nationwide community-based study in France on health and urinary condition, involving 2011 men aged between 50 and 80 years, information was collected on sexual life factors (e.g., frequency of sexual desires and sexual relations, and the frequency of having difficulties with erection and ejaculation) in addition to an assessment of overall sexual life satisfaction. Data on sexual life were obtained by means of a self-administered questionnaire, while information on the frequency of urinary symptoms was obtained by a professional interviewer. The median number of sexual relations decreased with age from "once per week" in those aged 50-59 years to "less than once per week" in those aged 60-69 years to "never" in those aged over 70 years, while the percentage reporting difficulty with erection at least some of the time increased from 20 to 38% between 50-59 and 70-79 years, respectively. The number of sexual relations during the past month was by far the most important factor having an influence on overall sexual life satisfaction, with those men reporting relations less than once per week almost 10 times more likely to be dissatisfied. Severity of overall urinary symptoms (as well as many individual symptoms) was also inversely related to sexual life satisfaction, and the association persisted after taking account of the strong influence of age and the frequency of sexual relations. All other factors being equal (age, number of relations, comorbidities, and previous prostate surgery), the likelihood of men being dissatisfied with sexual life increased twofold in men with moderate symptoms and fourfold in those with severe symptoms. The results obtained in the current study should be considered preliminary, given the complexity of the relationship between these two factors and the lack of previously published evidence. They certainly call for further studies, which should include a detailed assessment of sexual function and a clinical assessment of the urinary condition.

Aged↗
PubMed1996

Epidemiology of laryngeal cancer.

Laryngeal cancer is the second most common respiratory cancer after lung cancer. Its incidence is increasing over time in much of the world and this increase is generally accepted to be related to changes in tobacco and alcohol consumption. It is a relatively common cancer in men, but rarer in women. Moreover, interesting new issues have been raised recently about the influence of other possible risk factors. Evidence from epidemiological studies which supports the involvement of new risk factors in the aetiology of larynx cancer, as well as new perspectives in therapy, must be taken into consideration in order to realise primary and tertiary prevention. However, it remains clear that, even as new evidence continues to amass about a wide range of risk factors, primary prevention of the great majority of laryngeal cancers could be achieved by elimination of tobacco smoking and reduction of consumption of alcoholic beverages. With an additional contribution from adoption of a diet rich in fruits and vegetables, the great majority of laryngeal cancer appears to be preventable within our current epidemiological knowledge.

Adult↗
PubMed1996

The microenvironment influences the pattern of bacterial translocation in formula-fed neonates.

The authors previously demonstrated that neonatal rabbits fed conventional formula have a significantly greater incident of bacterial translocation than do neonatal rabbits fed breast milk. They hypothesized that exogenous bacteria in the formula and/or the microenvironment of the neonatal rabbit may contribute to the higher incidence of bacterial translocation. In the present study, the authors examined the incidence of bacterial translocation in neonatal rabbits fed pasteurized formula, unsterile formula, or breast milk while being housed in a clean or unsterile environment. The rabbits were divided into five groups. Groups I and II were fed pasteurized formula; groups III and IV were fed unsterile formula. In addition, groups I and III were housed in a clean environment, and groups II and IV were kept in an unsterile environment. The neonates in group V were fed breast milk and were kept in an unsterile environment. On the seventh day, the animals were killed, and the mesenteric lymph nodes, liver, and spleen were cultured for the presence of bacteria. Bacterial translocation occurred in 100% of group IV neonates. A clean environment (groups I and III) eliminated gram-negative bacterial translocation. A reduction (50%) in the overall incidence of bacterial translocation was obtained by pasteurizing the formula (group I v group III). Group II had significantly less gram-negative bacterial translocation than did group IV. None of the neonates in group V had translocation. The data show that a clean environment abrogates gram-negative bacterial translocation. Pasteurizing the formula significantly reduces the incidence of gram-negative bacterial translocation, and further reduces overall bacterial translocation in a clean environment. The authors hypothesize that control of the microenvironment can significantly influence the pattern of bacterial translocation in formula-fed neonates, and thus potentially reduce the incidence of gut-origin sepsis. Factors present in breast milk inhibit bacterial translocation, regardless of the microenvironment.

Animals↗
PubMed1996

Prostate volume predicts outcome of treatment of benign prostatic hyperplasia with finasteride: meta-analysis of randomized clinical trials.

OBJECTIVES: Six randomized clinical trials have compared at least 1 year of 5 mg finasteride to placebo in the treatment of clinical benign prostatic hyperplasia (BPH). The findings for the 2601 men in these trials provide an opportunity to investigate the heterogeneity of the effects seen in the individual studies and to identify pretreatment predictors of outcomes as expressed by symptoms or peak urinary flow rates. METHODS: A formal meta-analysis using an Empirical Bayes approach employed data from all finasteride studies which included the Phase III trials in North America and Internationally, the Prospect, Early Intervention, and SCARP trials, and the Veterans Administration Cooperative Study which compared terazosin, finasteride, and the combination of these two drugs. A pooled analysis was also undertaken on the combined dataset. RESULTS: The effect of finasteride treatment on improvements in total symptom severity, frequency score, and peak urinary flow rate was consistent across all six trials and similar among men with similar prostate volumes at baseline. Symptom severity improved by 1.8 points (95% confidence interval [CI], 0.7 to 2.9) in men with prostate volumes less than 20 cc (n = 72), while the improvement was 2.8 points (95% CI, 2.1 to 3.5) for men with volumes greater than 60 cc (n = 272) on the Quasi-IPSS Scale (range 0 to 30). Similarly, improvements in peak urinary flow rate ranged from 0.89 mL/s (95% CI, -0.05 to 1.83) for men with prostate volumes less than 20 cc to 1.84 mL/s (95% CI, 1.37 to 2.30) in men with volumes greater than 60 cc. The difference in the magnitude of improvement between finasteride and placebo becomes significant (that is, no overlap in 95% CI) for men with a baseline prostate volume assessed by either transrectal ultrasonography or magnetic resonance imaging of greater than 40 cc, which encompasses approximately 50% of the entire population. Baseline prostate volume is a key predictor of treatment outcomes: approximately 80% of the variation in the treatment effects noted between studies could be attributed to differences in mean prostate volumes at baseline. Variation in entry criteria results in large differences in baseline symptom severity status, prostate volume, and consequently apparent inconsistencies in the overall outcomes of these trials. CONCLUSIONS: This meta-analysis suggests that finasteride is most effective in men with large prostates. Men with small prostates may not be suitable candidates for finasteride therapy for BPH. The need for a careful reevaluation of the definitions and terminology used when discussing urination problems is apparent.

Enzyme Inhibitors↗
PubMed1996

The continuing increase in adenocarcinoma of the uterine cervix: a birth cohort phenomenon.

BACKGROUND: Adenocarcinoma of the uterine cervix has been reported to be increasing among young white women and earlier studies suggest a birth cohort pattern for the observed increase. No study, however, has examined the time trends of adenocarcinoma of the cervix by birth cohort. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) data through 1990, the current study is designed to examine the time trends of invasive adenocarcinoma by birth cohort. An age-period-cohort model was fitted to the annual-age-specific rates to identify the components of birth cohort and time period as determinants of the observed time trends. RESULTS: The results from this study clearly show that invasive adenocarcinoma of the uterine cervix has been increasing in both whites and blacks, but the increase is statistically significant only among whites, reaching 4.2 percent per year for those born since 1935. The results also show that the recent increase in invasive adenocarcinoma started among those born around the mid 1920s, and a strong birth cohort effect is largely responsible for the observed increase. CONCLUSION: Invasive adenocarcinoma of the uterine cervix is increasing among recent birth cohorts. Analytical epidemiological studies are urgently needed to explore the risk factors responsible for the increase. The time trends for adenocarcinoma of the cervix should also be carefully monitored in the coming years.

Adenocarcinoma↗
PubMed1996

Comparative descriptive epidemiology of oral and oesophageal cancers in Europe.

The two main determinants of oral and oesophageal cancer in Europe are alcohol and tobacco, and the two cancer sites show several similarities in their descriptive epidemiology. This study compares mortality from cancers of the oral cavity and oesophagus in European countries to evaluate similarities and differences. From official death certification numbers and population estimates, we obtained age-standardized rates for all ages and truncated (35-64 years). In most countries, rates for men tended to increase between 1955-59 and 1990-92 for both sites, although the increases were more marked for oral cancer. In the UK and Ireland, however, oral cancer decreased and oesophageal cancer increased, while in Finland and Iceland mortality for both sites decreased. The most striking increases were in Hungary, where the truncated rate in most recent calendar periods reached the highest levels in Europe. In France, rates for both cancers were extremely high: oral cancer increased from 1955-59 to the early 1980s, but started to decline afterwards. Mortality rates were much lower for women than men, and the correlation between the two sites was less marked. An age, period and cohort model, applied to the rates for men in selected European countries, suggested strong cohort effects for both cancers, generally more marked for oral cancer, with substantial increases in the cohorts born after 1920. The mortality rates of cancers of the oral cavity and oesophagus show several analogies, as expected from their relation to tobacco and alcohol; but some discrepancies suggest that other, less well-identified, factors may also influence their rates and trends in Europe.

Adult↗
PubMed1996

International comparison of the community prevalence of symptoms of prostatism in four countries.

We conducted an international comparison of the prevalence of urinary symptoms of prostatism in 4 countries, using a community-based random sampling of subjects, similar study procedures, and a single definition of cases that was based on a standardized symptom questionnaire. In Scotland 1,994 medically eligible men aged 40-79 years agreed to participate from 3 communities of the Forth Valley. In France, a nation-wide survey was conducted cross-sectionally in a representative sample of 2,011 French men aged 50-84 years. In the USA, the Olmsted County (OC) study recruited an age- and urban/rural-stratified random sample of 2,115 county residents drawn from medically eligible men aged 40-79 years. In Japan, 290 men aged 40-79 years from a fishing village participated in the study. Response rates were 55, 53, 55, and 43% in Scotland, France, OC and Japan, respectively. Urinary symptoms were assessed by the International Prostate Symptom Score (I-PSS), after metrologic validation in English and cross-cultural adaptation of the questionnaire. The prevalence of moderate to severe symptoms (I-PSS > 7) were 14, 18, 38, and 56% in France, Scotland, OC and Japan, respectively. This pattern was consistent within decades of age, and was found for most of the individual urinary symptoms. The proportion of men in Japan reporting very low I-PSS (0 or 1) was approximately 2, 4 and 8 times less frequent, than in OC, Scotland, and France, respectively. Differences in the prevalence of reported urinary symptoms might reflect between-country differences in the true prevalence of benign prostatic hyperplasia. However, cross-cultural differences in the perception and/or willingness to report urinary symptoms may play an important role in the observed differences. Further study will be required to elucidate the underlying causes of the observed differences.

Adult↗