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PubMed1997

Prostate cancer incidence and mortality rates among white and black men.

This paper presents prostate cancer incidence and mortality rates in the United States by factors associated with the disease at diagnosis and explores racial differences in these rates. The analysis is based on population-based cancer data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. Incidence rates increased sharply from 1973 to 1992 (more so among whites), with the increase attributed to screening and preferential finding of low-risk, slow-growing tumors (that is, length bias). Mortality rates increased slightly (more so among blacks). The 1988-1992 white and black prostate cancer mortality rates comprise cases diagnosed as early as 1973. These rates remained fairly constant for each stage category at diagnosis, except for black men diagnosed with localized or unstaged disease, in whom the rates increased. Of the white prostate cancer cases, 33% are diagnosed with localized disease, 16% are diagnosed with regional disease, and 38% are diagnosed with distant disease. The corresponding percentage for black patients are 31, 12, and 45%. Prostate cancer mortality rates for blacks diagnosed with localized, regional, distant, and unstaged disease are 1.9, 1.5, 2.4, and 2.0 times those of whites. The time from diagnosis to death depends on the stage and age at diagnosis, with the time somewhat longer for whites than blacks. This longer time period is due, in part, to better staging and length bias. The effect of therapy on prostate cancer mortality rates is unclear.

Adult↗
PubMed2006

Difference in the incidence trend of nasopharyngeal and oropharyngeal carcinomas in Taiwan: implication from age-period-cohort analysis.

Lifestyle factors are considered important for the pathogenesis of both nasopharyngeal and oropharyngeal carcinomas. In Taiwan, the incidence of nasopharyngeal carcinoma gradually decreased over the past 20 years, whereas that of oropharyngeal carcinoma increased rapidly. To compare the incidence trends of nasopharyngeal and oropharyngeal carcinomas in Taiwan, the age-period-cohort model was used to analyze epidemiologic data from 1981 to 2000 obtained from the Taiwan Cancer Registry. The calendar time period of 1986 to 1990 and the 1931 to 1940 birth cohort were used as reference groups for estimates of relative risk. For nasopharyngeal carcinoma, the incidence seemed to decrease in most age groups and was more prominent in women (30%) than in men (23%). For oropharyngeal carcinoma, the incidence increased in all age groups and was more prominent in men (391.4%) than in women (59.2%). Cohort effect was found for both nasopharyngeal and oropharyngeal carcinomas. The relative risk of nasopharyngeal carcinoma for the 1971 to 1980 birth cohort was 0.38 for women and 0.68 for men. The relative risk of oropharyngeal carcinoma for the 1971 to 1980 cohort was 45.67 for men and 2.69 for women. Change in lifestyle seemed to be an important factor for the difference in the incidence trend between nasopharyngeal and oropharyngeal carcinomas and between men and women.

Adult↗
PubMed2004

[Recent changes in prostate cancer mortality in Chile. Trends analysis from 1955 to 2001].

BACKGROUND: By the year 2000, prostate cancer became the second leading cause of cancer death in Chilean men of all ages and is the leading cause of cancer deaths in men of eighty years of age or older. AIM: To analyze the trends in mortality rates from prostate cancer in Chile in a fifty years series, estimating the rate of increase of such rates and their changes in time. MATERIAL AND METHODS: A trend analysis for age standardized mortality rates was performed, using join point regression analysis, which allows estimation of the annual percent change of rates and to find significant changes in such trend. RESULTS: Age standardized mortality rates in Chile reached their peak value in 1996, becoming apparently stable from then on. Crude rates have had a steady increase during the whole period. The trends analysis identified three different periods in the growth of the age standardized rates: a first one of slot increase in rates between 1955 and 1981 (0.9% annual increase), a second one of more aggressive growth starting in 1981 (2.6% annual increase), and a third period starting in 1996, in which rates slowly decline at an annual rate of 1%. CONCLUSIONS: The tendency of prostate cancer seen in Chile resembles that of industrialized countries, with an increase in its age standardized death rates that suffers a downturn by the end of the past decade. Besides early detection techniques, a substantial part of the reduction in mortality from prostate cancer could be explained by therapeutic improvements.

Age Distribution↗
PubMed2000

The impact of HIV infection on recurrence of tuberculosis in South African gold miners.

UNLABELLED: DESIGN AND OBJECTIVES: Potential risk factors for recurrence of tuberculosis (TB) were investigated in a retrospective cohort study of 305 human immunodeficiency virus (HIV) positive and 984 HIV-negative South African gold miners treated for TB with directly-observed, rifampicin-based regimens. Standard treatment changed from rifampicin, isoniazid and pyrazinamide (RHZ) to RHZ plus ethambutol (RHZE) during the study period. RESULTS: Recurrence occurred in 37 HIV-positive and 46 HIV-negative men. HIV infection was associated with a significantly higher recurrence rate (8.2 vs 2.2 per 100 person-years; multivariate-adjusted incidence rate ratio [IRR] 4.9, 95% confidence interval [CI] 3.0-8.1), as were post-tuberculous scarring (multivariate-adjusted IRR 1.6 for one or two scarred lung zones, 4.0 for three or more zones; test for trend P < 0.001) and drug resistance (multivariate-adjusted IRR 2.7, 95%CI 1.01-7.4). The recurrence rate was significantly higher following treatment with RHZ than RHZE (multivariate-adjusted IRR 2.1, 95%CI 1.1-4.0). The difference between regimens needs to be interpreted with caution, however, as allocation was not randomised. CONCLUSION: The high recurrence rate among HIV-positive men requires further investigation to distinguish relapse from re-infection as the predominant cause, leading to consideration of further intensification of the initial regimen or use of secondary prophylaxis.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Ecological studies].

Explore the source record for details and available documents.

Air Pollution↗
PubMed1992

Testing the null hypothesis in small area analysis.

The goal of small area analysis is often to demonstrate that hospital admission rates or procedure rates vary greatly among regions, suggesting the occurrence of unnecessary admissions or procedures in some regions. Recent articles have shown that such variation may be largely due to chance, even if no underlying differences exist among the small areas; thus, it is important to test if the observed variation is larger than expected by chance. In this article we discuss how the appropriate method for testing the null hypothesis depends on the distribution of the number of admissions at the person level. If it is not possible for an individual to have more than one admission for a given procedure, the appropriate test is a simple chi-square test. If multiple admissions are possible, a modified chi-square test can be used to account for the excess variability due to multiple admissions. Failure to make the correct modification to the chi-square test in this latter case can result in spurious results. This underscores the importance of collecting data on multiple admissions in order to estimate the distribution of the number of admissions at the individual-patient level.

Analysis of Variance↗
PubMed1990

Covariance in parasite burdens: the effect of predisposition to infection.

Recently the phenomenon of predisposition to helminth infection has been reported in a number of studies: those individuals which are heavily infected before treatment with an anthelmintic tend also to acquire heavy parasite burdens following a period of reinfection. This correlation between parasite burdens in initial and reinfections is generated by differences between hosts in their exposure to infective stages and in their susceptibility to infection. Inter-host differences in these factors also generate the aggregated or over-dispersed parasite distributions that are usually observed. This paper uses probability theory to predict the correlation between initial and reinfection parasite burdens assuming that those inter-host differences which generate over-dispersion remain constant for a given individual between initial and reinfection periods. The predicted correlation is considerably greater than is observed in most published data sets. Over-dispersion is thus generated by variability between hosts which has components that remain constant between initial and reinfection and also components which vary between infection periods. The model is modified to account for those two sources of variability, and the result applied to published data to determine the contributions made by short and long-term factors to the observed distributions.

Analysis of Variance↗
PubMed1996

Measurement of airborne 218Po--a Bayesian approach.

The standard mathematical treatment of the buildup and decay of airborne radionuclides on a filter paper uses the solutions of the so-called Bateman equations adapted to the sampling process. These equations can be interpreted as differential equations for the expectation of an underlying stochastic process, which describes the random fluctuations in the accumulation and decay of the sampled radioactive atoms. The process for the buildup and decay of airborne 218Po can be characterized as an "immigration-death process" in the widely adopted, biologically based jargon. The probability distribution for the number of 218Po atoms, accumulated after sampling time t, is Poisson. We show that the distribution of the number of counts, registered by a detector with efficiency epsilon during a counting period T after the end of sampling, is also Poisson, with mean dependent on epsilon, t, T, the flowrate and N(o), the number of airborne 218Po atoms per unit volume. This Poisson distribution was used to construct the likelihood given the observed number of counts. After inversion with Bayes' Theorem we obtained the posterior density for N(o). This density characterizes the remaining uncertainty about the measured number of 218Po atoms per unit volume of air.

Air Pollution, Radioactive↗
PubMed2006

What "Dr. Mom" ordered: a community-based exploratory study of parental self-care responses to children's ADHD symptoms.

Little is known about family initiated self-care interventions in response to symptoms of attention deficit/hyperactivity disorder (ADHD), and how self-care may co-exist with professional treatments. This paper explores parental self-care strategies for children with hyperactivity or attention problems, and examines factors and domains that influence their use from the mixed method perspective. As part of a longitudinal cohort study of ADHD detection and service use, caregivers of a representative US community sample of 266 children at high risk for ADHD completed a questionnaire that assessed five self-care strategies (behavior modification, coping, diet, over-the-counter medication use and religious practices), and made open-ended inquiry about discipline changes in response to behavioral concerns. Questionnaire responses were analyzed using logistic regression approaches. Open-ended answers were open coded; secondary analysis followed Spradley's model of domain analysis. Quantitative findings showed that behavior modification was the most commonly tried self-care strategy, followed by coping, diet, and religious practices. Over-the-counter trial was least common. The parents of professionally treated children were more likely to have employed behavior modification, coping strategies and over-the-counter medications than the parents of untreated children. Two-thirds of parents had changed their disciplinary action within three domains that were identified through qualitative analysis, including changes related to (a) the prevention of disciplinary problems (e.g., sustain eye contact, activation, consistency, clear instructions), (b) the solution of disciplinary problems (e.g., time-outs; privilege removal), and (c) parental coping associated with disciplinary problems (e.g., control own emotions, become less judgmental and more tolerant, and develop more appropriate expectations). These findings suggest that self-care strategies are commonly employed and appear to co-exist with professional treatment. Therefore, healthcare providers should actively explore parents' use of such strategies as some of them may interfere with prescribed treatments (e.g., over-the-counter) or absorb parental resources without likely benefit (e.g., diet).

Adaptation, Psychological↗
PubMed1992

The role of nematode parasites in Soay sheep (Ovis aries L.) mortality during a population crash.

In early 1989, two-thirds of the Soay sheep population on St Kilda died over 12 weeks. Post-mortem examinations revealed emaciated carcasses and considerable nematode burdens, with protein-energy malnutrition as the probable cause of death. Haematological and blood biochemical changes in the sheep, as well as fecundity of gastrointestinal nematodes, suggested the hosts were immunosuppressed. In parallel, laboratory experiments in which Soay sheep on a high plane of nutrition were artificially infected with Ostertagia circumcincta, showed no clinical signs or mortality when supporting worm burdens similar to those recorded in dead sheep on St Kilda. Anthelmintic treatment of a group of animals increased daily survival rates in ewes and male lambs, although treated animals became re-infected as the 'crash' progressed. It is suggested that parasites contribute to mortality in malnourished hosts, exacerbating the effects of food shortage.

Analysis of Variance↗
PubMed2001

Risk factors for meningococcal disease in university halls of residence.

A retrospective ecological study was undertaken to identify social and environmental factors associated with increased incidence of meningococcal disease in university halls of residence. A standardized questionnaire was sent to UK universities and colleges of higher education outside London, for distribution to halls containing at least 50 students. Incidence rate ratios of invasive meningococcal disease were obtained for a range of social and environmental variables. Multi-variable Poisson regression analysis identified 3 factors as having a strong association: a high proportion of first year undergraduate residents (P = 0.0008), decreasing smokiness of the hall bar (P < 0.0001), and opening of hall bar before 1990 (P = 0.0001). The inverse relationship between disease incidence and smokiness of bars was an unexpected finding, and may be due to confounding factors. Universities should continue to promote awareness of meningococcal disease, encourage vaccination of first year students against serogroup C disease, and where appropriate, take measures to reduce overcrowding.

Adult↗
PubMed2003

Dental and maxillofacial injuries among older New Zealanders during the 1990s.

Not only is the number of older people increasing in New Zealand, but a greater number of them are keeping their own teeth, with predictable consequences for the costs of treating (and rehabilitating) dental and maxillofacial trauma in that group. The aim of the study was to describe the occurrence of dental and maxillofacial trauma involving New Zealanders aged 65 and over during the 1990s. The investigation was a secondary analysis of routinely collected, national-level compensation and hospital treatment data. The analysis showed that: (1) there was an increase in the rate and absolute number of injuries among older people; (2) the dental trauma rate was highest among males in the youngest age group, while the facial fracture rate was highest among older females; and (3) there was a general increase in the contribution of falls to the occurrence of trauma. Measures which aim to reduce the occurrence of falls among older people will also reduce the oral and maxillofacial trauma rate in that age group.

Accidental Falls↗
PubMed2004

The peculiar pattern of mortality of Jews in Moscow, 1993-95.

Russian Jews, particularly men, have a large mortality advantage compared with the general Russian population. We consider possible explanations for this advantage using data on 445,000 deaths in Moscow, 1993-95. Log-linear analysis of the distribution of deaths by sex, age, ethnic group, and cause of death reveals a relatively high concentration of endogenous causes and a relatively low concentration of exogenous and behaviourally induced causes among Jews. There is also a significant concentration of deaths from breast cancer among Jewish women. Mortality estimates using the 1994 micro-census population as the denominator reveal an 11-year Russian-Jewish gap in the life expectancy of males at age 20, but only a 2-year life-expectancy gap for women. Only 40 per cent of the Russian-Jewish difference for men, but the entire difference for women, can be eliminated by adjustment for educational differences between the two ethnic groups. Similarities with other Jewish populations and possible explanations are discussed.

Age Distribution↗
PubMed2001

Alcohol and suicide in 14 European countries.

AIMS: To test the hypothesis that a positive population-level relationship between alcohol and suicide is more likely to be found in dry drinking cultures (as indicated by consumption level) than in wet drinking cultures. DESIGN: Gender- and age-specific suicide rates in 14 western European countries were analysed in relation to per capita alcohol consumption employing the Box-Jenkins technique for time series analysis. The country-specific estimates were pooled into low-, medium- and high-consumption countries. MEASUREMENTS: Suicide mortality data for 5-year age groups were converted into gender- and age-specific mortality rates. Alcohol sales expressed as litres of 100% alcohol per year and inhabitants 15 years and older were used as a measure of alcohol consumption. FINDINGS: A positive and significant relationship between per capita consumption and gender- and age-specific suicide rates was revealed most often in northern Europe and found least often in southern Europe. A stronger absolute alcohol effect for men was found only in northern Europe, whereas the relative alcohol effect was somewhat stronger for women in both northern and central Europe. Also, the suicide rate in younger age groups was more often significantly related to per capita consumption than suicide among the elder in northern and central Europe but not in southern Europe. CONCLUSIONS: The population-level association between alcohol and suicide is conditioned by cultural factors. In general, the suicide rate tends to be more responsive to changes in alcohol consumption in drinking cultures characterized by a low post-war per capita consumption compared to drinking cultures with higher consumption levels. The findings give support to the hypothesis derived from previous theoretical and empirical work, suggesting that suicide and alcohol is more closely connected in dry cultures than in wet cultures.

Adolescent↗
PubMed2006

Total serum cholesterol and recovery from disability among hospitalized older adults.

BACKGROUND: The association between total serum cholesterol and health outcomes among older adults is controversial. The objective of the present study was to determine within a cohort of acutely hospitalized disabled elderly patients whether total cholesterol predicts recovery from disability in basic activities of daily living (ADL). METHODS: Patients (3150) 65 years old or older admitted to 81 acute care units in Italy and presenting with ADL disability at hospital admission were included in this study. ADL disability was defined as need of assistance or total dependence in one or more ADLs (eating, dressing, personal hygiene, transferring, and toilet use). Recovery was defined as no disability at hospital discharge in any of the five ADLs considered. RESULTS: Mean age of study participants was 80.5 +/- 7.2 years, and 1305 (41.1%) were men. The rate of recovery from ADL disability was 14.5% for participants with total cholesterol < 200 mg/dL (n = 306/2108), 20.2% for those with total cholesterol between 200 and 239 mg/dL (n = 144/713), and 23.1% for those with total cholesterol > or = 240 mg/dL (n = 76/329). After adjustment for potential confounders, relative to that of patients with cholesterol < 200 mg/dL, risk ratios for recovery were 1.31 for participants with cholesterol between 200 and 239 mg/dL (95% confidence interval [CI], 1.07-1.62) and 1.36 (95% CI, 1.04-1.79) for those with cholesterol > or = 240 mg/dL. After exclusion of 769 patients with total cholesterol < 145 mg/dL, the risk ratios (compared with those for participants with cholesterol < 200 mg/dL) for recovery were 1.33 (95% CI, 1.07-1.66) for participants with cholesterol between 200 and 239 mg/dL and 1.41 (95% CI, 1.06-1.88) for patients with cholesterol > or = 240 mg/dL. CONCLUSIONS: Among hospitalized disabled older adults, elevated levels of cholesterol are associated with increased rate of recovery from ADL disability.

Activities of Daily Living↗
PubMed2000

Cervical cancer mortality in Australia: contrasting risk by Aboriginality, age and rurality.

BACKGROUND: The poor health status of Australia's indigenous population is reflected in relatively high mortality rates from almost all causes, including preventable causes such as cervical cancer, where the rate is six to eight times that of non-Aboriginal women. However, there is little information on the geographical distribution of risk, an important issue for service deployment. This study examined the risk of death from cervical cancer in relation to Indigenous status, age and rurality. METHODS: Data from death registers from Australian states and territories who have identified Aboriginal people were examined for 1986-1997 to obtain a list of all deaths where the primary cause was cancer of the cervix. The data categorized females by 5-year age group, by metropolitan, rural or remote category and by Indigenous status. Mean age at death and standardized mortality ratios for deaths from cervical cancer were calculated for Aboriginal compared with non-Aboriginal women in metropolitan, rural and remote areas. RESULTS: The risk of death from cervical cancer for Aboriginal women compared with non-Aboriginal women increased by 4.3-fold for metropolitan areas, 9.7-fold for rural areas and 18.3-fold for remote areas. CONCLUSIONS: Aboriginal women in rural and remote areas of Australia are at significantly higher risk of death from cancer of the cervix than either Aboriginal women in metropolitan areas or non-Aboriginal women in any area. This result raises questions about access to services for prevention and early diagnosis and other factors that might impact on the incidence and natural history of the disease.

Adult↗