Carol Bigelow

Temporal Trends in Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND Limited information is available on trends in the incidence of and mortality due to cardiogenic shock complicating acute myocardial infarction. We studied the incidence of cardiogenic shock complicating acute myocardial infarction and in-hospital death rates among patients with this condition in a single community from 1975 through 1997. METHODS We conducted an observational study of 9076 residents of metropolitan Worcester, Massachusetts, who were hospitalized with confirmed acute myocardial infarction in all local hospitals during 11 one-year periods between 1975 and 1997. Our study included periods before and after the advent of reperfusion therapy. RESULTS The incidence of cardiogenic shock remained relatively stable over time, averaging 7.1 percent among patients with acute myocardial infarction. The results of a multivariable regression analysis indicated that the patients hospitalized during recent study years were not at a substantially lower risk for shock than patients hospitalized in the mid-to-late 1970s. Patients in whom cardiogenic shock developed had a significantly greater risk of dying during hospitalization (71.7 percent) than those who did not have cardiogenic shock (12.0 percent, P<0.001). A significant trend toward an increase in in-hospital survival among patients with cardiogenic shock in the mid-to-late 1990s was found in crude and adjusted analyses. CONCLUSIONS Our findings indicate no significant change in the incidence of cardiogenic shock complicating acute myocardial infarction over a 23-year period. However, the short-term survival rate has increased in recent years at the same time as the use of coronary reperfusion strategies has increased.

Racial differences in tumor stage and survival for colorectal cancer in an insured population

Despite declining death rates from colorectal cancer (CRC), racial disparities have continued to increase. In this study, the authors examined disparities in a racially diverse group of insured patients.

Video display terminal workstation improvement program: I. Baseline associations between musculoskeletal discomfort and ergonomic features of workstations.

Associations between selected sites of musculoskeletal discomfort and ergonomic characteristics of the video display terminal (VDT) workstation were assessed in analyses controlling for demographic, psychosocial stress, and VDT use factors in 273 VDT users from a large administrative department. Significant associations with wrist/hand discomfort were seen for female gender; working 7+ hours at a VDT; low job satisfaction; poor keyboard position; use of new, adjustable furniture; and layout of the workstation. Significantly increased odds ratios for neck/shoulder discomfort were observed for 7+ hours at a VDT, less than complete job control, older age (40 to 49 years), and never/infrequent breaks. Lower back discomfort was related marginally to working 7+ hours at a VDT. These results demonstrate that some characteristics of VDT workstations, after accounting for psychosocial stress, can be correlated with musculoskeletal discomfort.

Outcomes of a 21-Day Drug Detoxification Program: Retention, Transfer to Further Treatment, and HIV Risk Reduction

We investigated the outcomes of a 21-day inpatient drug detoxification and rehabilitation program including length of stay, transfer to further treatment, and HIV risky behavior. Clients (n = 567) were predominantly White, male, currently unemployed, and their treatment was not covered by third party payment. 78% were detoxified with methadone. The median length of stay was 18 days. Higher education, not living with spouse or children, English as primary language, admission during fall or winter months, and greater knowledge of HIV transmission were independent predictors of greater length of stay. Among those with follow-up (n = 450), 19% were transferred to residential drug-free programs and 7% to outpatient programs. Taking into account loss to follow-up, the overall rate of treatment transfer could be as low as 21%. Greater length of stay was associated with higher rates of transfer to residential treatment. Relapse rates to either any drug use or injection drug use were lower among subjects transferred to residential treatment than either clients transferred to outpatient programs or those with no further treatment. Among subjects who continued to inject drugs at follow-up, no reduction in HIV risky behaviors was found regardless of further treatment. We conclude that detoxification programs have the potential for reducing relapse to drug use when followed by residential drug-free treatment.

Risk factors for psychological stress among international business travellers.

OBJECTIVES: This study investigated sources of self reported psychological stress among international business travellers at the World Bank, following up on a previous study showing that travellers submitted more insurance claims for psychological disorders. Hypotheses were that work, personal, family, and health concerns, as well as time zone travel, contribute to travel stress. METHODS: A travel survey was developed from focus groups and consisted of questions about these potential sources of travel stress. Surveys were sent to a random sample of staff, stratified by number of travel missions, age range, and sex. Canonical correlation analyses estimated the association between key survey items on sources of stress and two measures of travel stress. RESULTS: 498 staff completed the survey. More than a third reported high to very high travel stress. Correlations between predictors and travel stress showed that social and emotional concerns (such as impact of travel on family and sense of isolation) contributed the most to such stress, followed by health concerns, and workload upon return from travel. Surprisingly, time zone travel did not contribute to the self reported stress of these travellers. There were few modifiers of stress, although respondents suggested that a day of rest after travel and reduced workloads would help. CONCLUSIONS: The current study confirms clinical impressions about several correlates of travel stress. Similar research with travellers in other organisations could help to determine whether the findings from this study are valid and what measures can be taken to reduce the psychological health risks to travellers.

Repression of mammary stem/progenitor cells by p53 is mediated by notch and separable from apoptotic activity

Breast cancer is the most common tumor among women with inherited mutations in the p53 gene (Li‐Fraumeni syndrome). The tumors represent the basal‐like subtype, which has been suggested to originate from mammary stem/progenitor cells. In mouse mammary epithelium, mammosphere‐forming potential was increased with decreased dosage of the gene encoding the p53 tumor suppressor protein (Trp53). Limiting dilution transplantation also showed a 3.3‐fold increase in the frequency of long‐term regenerative mammary stem cells in Trp53−/− mice. The repression of mammospheres by p53 was apparent despite the absence of apoptotic responses to radiation indicating a dissociation of these two activities of p53. The effects of p53 on progenitor cells were also observed in TM40A cells using both mammosphere‐forming assays and the DsRed‐let7c‐sensor. The frequency of long‐term label‐retaining epithelial cells was decreased in Trp53−/− mammary glands indicating that asymmetric segregation of DNA is diminished and contributes to the expansion of the mammary stem cells. Treatment with an inhibitor of γ‐secretase (N‐[N‐(3,5‐difluorophenacetyl)‐L‐alanyl]‐S‐phenylglycine t‐butyl ester) reduced the number of Trp53−/− mammospheres to the level found in Trp53+/+ cells. These results demonstrate that basal levels of p53 restrict mammary stem/progenitor cells through Notch and that the Notch pathway is a therapeutic target to prevent expansion of this vulnerable pool of cells. STEM CELLS 2011;29:119–127

Video display terminal workstation improvement program: II. Ergonomic intervention and reduction of musculoskeletal discomfort.

The effects of an ergonomic intervention on musculoskeletal discomfort in 118 video display terminal (VDT) users were assessed 1 year after intervention. The intervention consisted of recommended changes to workstations, which were based on the evaluation of 15 ergonomic characteristics. Compliance with the intervention was at least 75% for most workstation characteristics. Reduction in discomfort was substantial and was highest for the wrist/hand (57%), lower back (43%), and neck/shoulder (41%) severity of discomfort outcomes. Neither compliance with intervention on individual workstation characteristics nor summary intervention scores were associated with reduction in discomfort. Our results demonstrate that although reduction of musculoskeletal discomfort may be observed in the context of an intervention study, it may be difficult to link these benefits to specific interventions.

Radioimmunoassay of hair for determination of cocaine, heroin, and marijuana exposure : comparison with self-report

Radioimmunoassay of hair (RIAH) was compared with self-report for cocaine, heroin, and marijuana in two populations: 109 persons entering residential drug user treatment and 86 at follow-up posttreatment. Among treatment entrants, 89% of 87 RIAH cocaine-positives and 96% of 45 RIAH heroin-positives were confirmed by self-report. However, among those followed-up posttreatment, only 51% of 43 RIAH cocaine-positives and 67% of 18 RIAH heroin-positives were so confirmed. Whereas 95% of 104 self-reports of cocaine use in the combined population were confirmed by RIAH, only 69% of 80 self-reports of heroin use were. Self-report and RIAH for marijuana were weakly associated.

The effectiveness of alternative planned durations of residential drug abuse treatment.

Randomized controlled trials were conducted at two residential drug abuse treatment facilities to compare programs that differed in planned duration. One trial compared a 6-month and a 12-month therapeutic community program (n = 184), and the second compared a 3-month and a 6-month relapse prevention program (n = 444). Retention rates over comparable time periods differed minimally by planned treatment duration, and the longer programs had lower completion rates. There was no effect in either trial of planned treatment duration on changes in psychosocial variables between admission and exit or on rates or patterns of drug use at follow-up between 2 and 6 months after exit.

Modeling Nonlinear Dose-Response Relationships in Epidemiologic Studies: Statistical Approaches and Practical Challenges

Non-linear dose response relationships pose statistical challenges for their discovery. Even when an initial linear approximation is followed by other approaches, the results may be misleading and, possibly, preclude altogether the discovery of the nonlinear relationship under investigation. We review a variety of straightforward statistical approaches for detecting nonlinear relationships and discuss several factors that hinder their detection. Our specific context is that of epidemiologic studies of exposure-outcome associations and we focus on threshold and J-effect dose response relationships. The examples presented reveal that no single approach is universally appropriate; rather, these (and possibly other) nonlinearities require for their discovery a variety of both graphical and numeric techniques.