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Biomedical subjects

R B Rothenberg

Publications and source records attributed to R B Rothenberg.

At least 37 records · Page 2Linked to original sources
PubMed1995

The natural history of exercise: a 10-yr follow-up of a cohort of runners.

To determine the pattern of exercise and associated adverse events, including injuries, a mail survey was conducted on participants in the 1980 Peachtree Road Race Study for whom we were able to obtain current addresses. A total of 535 persons responded, 326 men and 209 women, representing 72% of those with identifiable addresses. Although only 56% of respondents reported that they were still running in 1990, 81% reported that they were still exercising regularly. The cumulative probability for continuing to run was 0.71 for men and 0.56 for women. Injury (31%) was the chief reason given by men for stopping permanently. For women, 28% stopped because they chose another form of exercise. Fifty-three percent of respondents had at least one injury during the 10-yr interval. The probability of experiencing an injury was associated with higher weekly mileage. The knee was the most frequently injured site. Thirty-nine percent of women and 35% of men reported being verbally assaulted. Approximately 10% of persons were hit by thrown objects or bitten by a dog. In a group of recreational runners, almost half had stopped running 10 yr later, but over 80% were still physically active. Many runners sustain injuries or suffer hazards related to their exercise.

Adult↗
PubMed1994

Competing mortality and progress against cancer.

The decline in ischemic heart disease (IHD) mortality in the United States in recent years is thought to have contributed to increases in cancer mortality. To estimate the interrelation between these competing causes of death between 1970 and 1988, I constructed a hypothetical population schedule by assuming that age-specific IHD mortality risks had not declined. The difference between the actual population and the hypothetical population represents persons who did not die from IHD and were thus available to die from cancer. Using observed age-specific cancer risks over the entire interval, 153,207 of the 7,649,058 cancer deaths (2.0%) in persons age 20-85 years occurred in IHD survivors; in 1988, 24,053 of the 482,490 cancer deaths (5.0%) occurred in IHD survivors. Among 55 to 85 year olds in 1988, IHD survivors accounted for 5.5% of the cancer deaths. Alternative assumptions about the susceptibility of IHD survivors to cancer have little impact on the contribution of IHD survivors to cancer deaths. Results from a separate analysis demonstrated that the proportional contribution of true cancer risk to the increase in cancer cases tripled in the interval 1970-1988 compared with the interval 1930-1970. These observations indicate that the contribution of the IHD mortality decline to the increase in cancer mortality has been small and does not account for the increasing age-specific risks for cancer among older persons.

Adult↗
PubMed1994

Mapping a social network of heterosexuals at high risk for HIV infection.

OBJECTIVE: To determine how heterosexuals at risk for HIV infection interconnect in social networks and how such relationships affect HIV transmission. DESIGN: Cross-sectional study with face-to-face interviews to ascertain sociosexual connections; serologic testing. PARTICIPANTS: Prostitute women (n = 133), their paying (n = 129) and non-paying (n = 47) male partners; injecting drug users (n = 200) and their sex partners (n = 41). Participants were recruited in sexually transmitted disease and methadone clinics, an HIV-testing site, and through street outreach in Colorado Springs, Colorado, USA. MAIN OUTCOME MEASURES: Reported behaviors, risk perceptions, sociosexual linkages, and HIV prevalence. RESULTS: Respondents were well informed, but reported engaging in high-risk behaviors frequently. Nevertheless, over 70% of respondents perceived themselves to be at low risk for HIV infection. The 595 respondents identified a social network of 5162 people to which they belonged. Network analytic methods indicated 147 separate connected components of this network; eight of the 19 HIV-positive individuals in the network were located in smaller components remote from the largest connected component. CONCLUSION: The isolated position of HIV-positive individuals may serve as a barrier to HIV transmission and may account for the lack of diffusion of HIV in heterosexual populations in this region. Network analysis appears useful for understanding the dynamics of disease transmission and warrants further development as a tool for intervention and control.

Adult↗
PubMed1993

AIDS in Colorado Springs: is there an epidemic?

OBJECTIVE: To analyze trends and patterns of HIV infection in a medium-sized community in the United States. METHODS: Surveillance for AIDS and HIV infection was conducted by private physicians, military and public clinics, and blood and plasma donation centers. HIV-positive individuals were contacted and asked to refer their sex and injection partners for HIV-antibody testing. Prostitutes, injecting drug users and their sex partners were studied. Selected physicians were surveyed to assess under-reporting. RESULTS: The 740 HIV-infected adults (67 with documented seroconversion) included 506 with no evidence of AIDS, 58 living with AIDS, and 176 who had died. Of the 126 patients cared for by local physicians, 107 (85%) had been reported. No major changes in behavioral risk factors or increases in the number of HIV-infected individuals occurred between 1986 (128) and 1992 (95). CONCLUSIONS: Characteristics of individuals at risk and incidence of HIV infection have remained stable from 1981 to 1992. Analysis of data from the comprehensive surveillance and control program established in Colorado Springs in response to the AIDS epidemic suggests that, unlike the nation's epicenters, HIV incidence in this location is neither widespread nor rapidly increasing. The age distribution of reported cases is slowly increasing, and the ratio of newly reported cases to deaths is declining, implying stable or decreasing incidence; deaths may soon exceed new cases. Using data routinely available to public health officials, we conclude that the epidemiologic picture of AIDS--like the clinical one--must be heterogeneous, and that rational planning for the impact of AIDS should be based on the collection and analysis of local data.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Excess deaths from nine chronic diseases in the United States, 1986.

To assess excess mortality from chronic disease in the United States, state age-adjusted combined mortality rates for nine chronic diseases in 1986 were compared with three "minimum" rates--two calculated from rates actually achieved in states and a third estimated as the mortality remaining after elimination of one risk factor for each disease. Hawaii had the lowest mortality rate of combined diseases (305/100,000); state excesses ranged from 0% to 37%. The sum of lowest disease-specific rates in any state was 284 per 100,000, indicating excesses of between 7% and 41%. A minimum mortality rate of 224 per 100,000 was estimated to result from elimination of one risk factor for each of the nine diseases, indicating state excesses from 26% to 54%, or 524,000 US deaths. Reduction of US mortality from the nine diseases to the risk factor--eliminated rate is estimated to be associated with an increased life expectancy at birth of 4 years.

Chronic Disease↗
PubMed1990

Application of the Cox model as a predictor of relative risk of coronary heart disease in the Albany Study.

Patients in long term studies of coronary heart disease may have different levels of risk during the course of study. Smoking habits, blood pressure, and obesity may change drastically during this period. The multiple logistic model, the most commonly used model for the analysis of coronary heart disease studies, does not consider survival time in assessment of the dependent covariates and does not account for the censoring which usually occurs in such studies. We propose a Cox model with time-dependent covariates to model the risk of coronary heart disease in the Albany study. The Cox model we fitted evaluates the patients' risk on the basis of the data at the last visit. With this methodology, we can evaluate whether it is advantageous for individuals to modify their risk of disease by their effecting changes in their covariates, that is to stop smoking, lose weight, change diet and so on. The important covariates that explain the risk of coronary heart disease were the same in our model as in the models used in the earlier reports. The estimated relative risks were slightly higher in most cases and lend more support to the need to encourage patients to achieve a better covariate state.

Adult↗
PubMed1988

Identifying important results from multiple statistical tests.

When many statistical tests are performed simultaneously, the overall chance of a type I error (incorrect rejection of a true null hypothesis) can substantially exceed the nominal error rate used in each individual test. Numerous techniques exist to adjust results of individual tests to control this problem. In general, these techniques apply a more stringent criterion of statistical significance (a smaller P-value) to each individual test than normally needed to maintain the experimentwise type I error. With an analysis that seeks to identify results for further research, however, such a conservative technique may not be appropriate. We present a new approach that uses a mixture of several distributions to model the set of P-values or of test statistics. One component models the results consistent with a failure to reject the null hypothesis, while the other distribution(s) in the mixture represent results inconsistent with the null hypothesis. These latter results may not achieve statistical significance based on a conventional P-value. We illustrate the use of the method on national mortality data and on several data sets analysed previously.

Cause of Death↗
PubMed1985

Observations on the application of EPI cluster survey methods for estimating disease incidence.

The present study attempted to assess the incidence of target diseases of the Expanded Programme on Immunization (poliomyelitis, tetanus, measles, pertussis, neonatal tetanus, diphtheria), using cluster samples and a household interview form. The results suggest that this method can indeed serve to estimate the incidence of these diseases with reasonable precision and may also be used to demonstrate reduction in incidence for the more common diseases. Analysis of 37 surveys for poliomyelitis and neonatal tetanus in India revealed a relative uniformity in the design effect (i.e., the ratio of the variance for the cluster estimate to the variance for the binomial estimate) for diseases with low incidence and prevalence. Diseases with higher prevalence tend to have a larger design effect, which may be indicative of the epidemic and "clustered" nature of the disease. A large design effect, therefore, does not necessarily indicate a need for a larger sample size, particularly if precision is acceptable. There is no one single design that is ideal for all surveys of disease incidence and decisions must be made in the light of local conditions and available resources.

Child↗
PubMed1983

The geography of gonorrhea. Empirical demonstration of core group transmission.

The pattern of reported gonorrhea in Upstate New York (exclusive of New York City) in the years 1975-1980 is one of intense central urban concentration, with concentric circles of diminishing incidence. The relative risk for gonorrhea in these central core areas, compared to background state rates, is 19.8 for men and 15.9 for women, but as high as 40 in selected census tracts. Prevalence appears to approach 20% in some areas, the level postulated by current epidemiologic models for continuing endemic transmission. These core areas are characterized by high population density, low socioeconomic status and a male to female case ratio of one or lower. Contact investigation data suggest that sexual contact tends to exhibit geographic clustering as well. These observations provide support for narrow focusing of epidemiologic resources as a major disease control strategy.

Epidemiologic Methods↗
PubMed1980

Gonococcal pelvic inflammatory disease: case-finding observations.

During a 20 month period, 110 women with gonococcal pelvic inflammatory disease an 165 women with uncomplicated gonorrhea were provided intensive case-finding services (interviewing of patients and tracing of contacts). Approximately three contacts per case were investigated, and 24.3% of the 859 male contacts were infected. Nearly two thirds (64.6%) of the infected contacts were asymptomatic. Active public health intervention was frequently necessary to persuade asymptomatic men to seek medical attention; removal of these men from the disease pool may serve to prevent reinfection of treated women and to diminish the transmission of gonorrhea.

Colorado↗
PubMed1980

Focused interviewing in gonorrhea control.

To develop an operational approach to the identification of high risk gonorrhea transmitters, three groups of women infected with Neisseria gonorrhoeae (recent repeaters, routine discoveries, and women with pelvic inflammatory disease) were offered intensive casefinding services during an 18-month period. Approximately three contacts per case were investigated, and 27.4% of the contacts were infected. Of infected contracts, 61% were asymptomatic. Asymptomatic, remote contacts to these women appear to be important in the continuing transmission of gonorrhea. The interviewing approach used reflected that employed in syphilis (thorough, detailed, and long) rather than the more casual interviews usually employed for gonorrhea patients. During this period, gonorrhea morbidity declined 22%. Further exploration of a targeted approach to gonorrhea epidemiology is indicated.

Adolescent↗