Colorectal cancer screening issues: a role for CT colonography?

Colorectal cancer is the third most common cancer in the United States and will cause 56,700 deaths in 2001, despite the availability of screening tests capable of detecting the disease at earlier stages and reducing mortality. This article reviews the natural history of colorectal cancer, common risk factors and prevention strategies, and the strengths, limitations, and cost effectiveness of available screening tests. Although reminders to undergo colorectal cancer screening have become commonplace in the popular media, compliance with screening guidelines remains poor. Although still an unproven technology for widespread screening, computed tomographic (CT) colonography has several attractive characteristics for a screening test. For example, CT scanners are widely available, in contrast to limited numbers of gastroenterologists and radiologists' declining skill and interest in barium enema examinations. Also, patients may be less reluctant to undergo CT colonography than screening colonoscopy. Development of virtual bowel cleansing could further increase compliance and thereby reduce mortality from colorectal cancer. Other articles in this Feature Section discuss technical details of CT colonography and its methodologic challenges.

Pancreatic cancer: cost-effectiveness of imaging technologies for assessing resectability

PURPOSE

To evaluate the cost-effectiveness of imaging strategies for the assessment of resectability in patients with pancreatic cancer.

MATERIALS AND METHODS

A decision model was developed to calculate costs and benefits (survival) accruing to hypothetical cohorts of patients with known or suspected pancreatic cancer. Results are presented as cost per life-year gained under various scenarios and assumptions of diagnostic test characteristics, surgical mortality, disease characteristics, and costs.

RESULTS

With best estimates for all data inputs, the strategy of computed tomography (CT) followed by laparoscopy and laparoscopic ultrasonography (US) had an incremental cost-effectiveness ratio of $87,502 per life-year gained, compared with best supportive care. This strategy was significantly more cost-effective than CT followed by magnetic resonance (MR) imaging and was significantly less expensive than other imaging strategies while providing a statistically and clinically insignificant difference in life-year gains. A strategy involving no imaging (immediate surgery) was more expensive but less effective than all imaging strategies. A hypothetical perfect test with cost equal to that of CT followed by MR had an incremental cost-effectiveness ratio of $64,401 per life-year gained, compared to best supportive care.

CONCLUSION

Most available imaging tests for assessing resectability of pancreatic cancer do not differ in effectiveness, but a strategy of CT, laparoscopy, and laparoscopic US would consistently result in significantly lower costs than other imaging tests under a wide range of scenarios.

Potential influence of acute CT on inpatient costs in patients with ischemic stroke

RATIONALE AND OBJECTIVES

Patients presenting with ischemic brain symptoms have widely variable outcomes dependent to some degree on the pathologic basis of their stroke syndrome. The purpose of this study was to determine the cost implications of the emergency use of a computed tomographic (CT) protocol comprising unenhanced CT, head and neck CT angiography, and whole-brain CT perfusion.

MATERIALS AND METHODS

By using a retrospective patient database from a tertiary care facility and publicly available cost data, the authors derived the potential savings from the use of CT angiography. CT perfusion, or both at hospital arrival by means of a cost model. The cost of the CT angiography-CT perfusion protocol was determined from Medicare reimbursement rates and compared with that of traditional imaging protocols. Cost savings were estimated as a decrease in the length of stay for most stroke patients, whereas the most benign (lacunar) strokes were assumed to be managed in a non-acute setting. Misdiagnosis cost (erroneously not admitting a patient with nonlacunar stroke) was calculated as the cost of a severe complication. Sensitivity testing included varying the percentage of misdiagnosed patients and admitting patients with lacunar stroke.

RESULTS

The nationwide net savings that would result from the adoption of the CT angiography-CT perfusion protocol are in the $1.2 billion range (-$154 million to $2.1 billion) when patients with lacunar strokes are treated nonacutely and $1.8 billion when those patients are admitted for acute care.

CONCLUSION

The results demonstrate the potential effect of implementing a CT angiography-CT perfusion protocol. In particular, prompt CT angiography-CT perfusion imaging could have an effect on the cost of acute care in the treatment of stroke.

Hospital costs for elective endovascular and surgical repairs of infrarenal abdominal aortic aneurysms

PURPOSE

To determine and compare the average in-hospital costs of elective open surgical and endovascular repairs of infrarenal abdominal aortic aneurysms.

MATERIALS AND METHODS

Total actual cost data for patients undergoing elective endovascular (n = 181) or open surgical (n = 273) repair of abdominal aortic aneurysms between 1997 and 1999 were retrieved. The mean total hospital cost (including stent-graft costs and excluding attending physician fees) and mean postoperative length of stay were calculated for each treatment group. Costs were expressed in 1999 U.S. dollars.

RESULTS

Endovascular repair yielded a shorter postoperative length of stay than did open surgery (mean stay, 3.4 vs 8.0 days; P <.001) and a lower proportion of patients who were admitted to the intensive care unit for 1 full day or longer (2.8% vs 36.3%; P <.001). The mean total hospital cost was significantly higher for endovascular repair than for open surgery ($20,716 vs $18,484; P <.001).

CONCLUSION

Hospital costs were higher for endovascular repair than for open surgical repair. However, endovascular repair was associated with a decreased length of stay and fewer intensive care unit admissions. The increased mean hospital cost for endovascular repair was smaller than one would expect, considering the higher costs of endovascular grafts, as compared with those for surgical grafts (approximately $6,400 according to literature data).

Cost-effectiveness of colorectal cancer screening

PURPOSE

To determine the most cost-effective colorectal cancer screening strategy costing less than $100,000 per life-year saved and to determine how available strategies compare with each other.

MATERIALS AND METHODS

Standardized methods were used to calculate incremental cost-effectiveness ratios (ICERs) from published estimates of cost and effectiveness of colorectal cancer screening strategies, and the direction and magnitude of any effect on the ratio from parameter estimate adjustments based on literature values were estimated.

RESULTS

Strategies in which double-contrast barium enema examination was performed emerged as optimal from all studies included. In average-risk individuals, screening with double-contrast barium enema examination every 3 years, or every 5 years with annual fecal occult blood testing, had an ICER of less than $55,600 per life-year saved. However, double-contrast barium enema examination screening every 3 years plus annual fecal occult blood testing had an ICER of more than $100,000 per life-year saved. Colonoscopic screening had an ICER of more than $100,000 per life-year saved, was dominated by other screening strategies, and offered less benefit than did double-contrast barium enema examination screening.

CONCLUSION

Double-contrast barium enema examination can be a cost-effective component of colorectal cancer screening, but further modeling efforts are necessary.

Cost-effectiveness of functional imaging tests in the diagnosis of Alzheimer disease

PURPOSE

To evaluate the cost-effectiveness of functional neuroimaging in the work-up of patients at specialized Alzheimer disease clinics.

MATERIALS AND METHODS

A decision model was used to calculate costs and benefits (in quality-adjusted life-years [QALYs]) that accrued to hypothetical cohorts of patients at presentation to an Alzheimer disease center. Sensitivity analysis was performed to examine the effects of diagnostic test characteristics, therapeutic efficacy, disease severity, and costs on cost-effectiveness.

RESULTS

The incremental cost-effectiveness ratio of dynamic susceptibility contrast material-enhanced magnetic resonance (MR) imaging was $479,500 per QALY (compared with the usual diagnostic work-up), while visual or quantitative single photon emission computed tomography (SPECT) was dominated (higher costs, lower effectiveness) by the usual diagnostic work-up. These results depend critically on the sensitivity and specificity of the standard diagnostic work-up, the effectiveness of drug treatment, and the disease severity. Varying these parameters resulted in estimates of incremental cost-effectiveness for dynamic susceptibility contrast-enhanced MR imaging of $24,680 to $8.6 million per QALY. SPECT either was dominated by the usual diagnostic work-up or had cost-effectiveness ratios of $180,200 to $6 million per QALY.

CONCLUSION

The addition of functional neuroimaging to the usual diagnostic regimen at Alzheimer disease clinics is not cost-effective given the effectiveness of currently available therapies.

Sexual violence and reproductive health

Sexual violence is a significant public health problem, and has been linked to adverse effects on women's physical and mental health. Although some advances in the research have been made, more scientific exploration is needed to understand the potential association between sexual violence and women's reproductive health, and to identify measures that could be implemented in reproductive health care settings to assist women who have experienced sexual violence. Three general areas needing further study include (1) expansion of the theoretical frameworks and analytic models used in future research, (2) the reproductive health care needs of women who have experienced sexual violence, (3) and intervention strategies that could be implemented most effectively in reproductive health care settings.

Screening for colorectal cancer

Colorectal cancer is the third most commonly diagnosed cancer and the second leading cause of cancer deaths in the United States. Fortunately, both the incidence and mortality associated with the disease have declined during the past 2 decades. This is likely due, at least in part, to improved efforts at screening and more aggressive removal of adenomatous polyps. However, colorectal cancer screening is still generally underutilized. This article reviews the current status and future outlook for colorectal cancer screening, including a discussion of risk factors for the disease, its anatomic distribution, proposed mechanisms of development from adenomatous polyps, rationale for screening, and screening options. Published literature concerning the cost-effectiveness of colorectal cancer screening is also summarized. The article concludes with a discussion of the emerging consensus regarding the importance of and approaches to screening.

The public health approach to the prevention of sexual violence

This paper presents the public health approach to the prevention of sexual violence. The public health approach addresses primary, secondary, and tertiary levels of prevention. An explanation of each level of prevention is given as it relates to the area of sexual violence. Additionally, the public health approach attempts to shift the focus of prevention from potential victims to potential perpetrators. The four steps of the public health model are presented with examples of how the Centers for Disease Control and Prevention are applying this model to sexual violence prevention.

Unintended pregnancy among adult women exposed to abuse or household dysfunction during their childhood

CONTEXT

Studies have identified childhood sexual and physical abuse as a risk factor for adolescent pregnancy but the relationship between exposure to childhood abuse and unintended pregnancy in adulthood has, to our knowledge, not been studied.

OBJECTIVE

To assess whether unintended pregnancy during adulthood is associated with exposure to psychological, physical, or sexual abuse or household dysfunction during childhood.

DESIGN AND SETTING

Analysis of data from the Adverse Childhood Experiences Study, a survey mailed to members of a large health maintenance organization who visited a clinic in San Diego, Calif, between August and November 1995 and January and March 1996. The survey had a 63.4% response rate among the target population for this study.

PARTICIPANTS

A total of 1193 women aged 20 to 50 years whose first pregnancy occurred at or after age 20 years.

MAIN OUTCOME MEASURE

Risk of unintended first pregnancy by type of abuse (psychological, physical, or sexual abuse; peer sexual assault) and type of household dysfunction (physical abuse of mother by her partner, substance abuse by a household member, mental illness of a household member).

RESULTS

More than 45% of the women reported that their first pregnancy was unintended, and 65.8% reported exposure to 2 or more types of childhood abuse or household dysfunction. After adjustment for confounders (marital status at first pregnancy and age at first pregnancy), the strongest associations between childhood experiences and unintended first pregnancy included frequent psychological abuse (risk ratio [RR], 1.4; 95% confidence interval [CI], 1.2-1.6), frequent physical abuse of the mother by her partner (RR, 1.4; 95% CI, 1.1-1.7), and frequent physical abuse (RR, 1.5; 95% CI, 1.2-1.8). Women who experienced 4 or more types of abuse during their childhood were 1.5 times (95% CI, 1.2-1.8) more likely to have an unintended first pregnancy during adulthood than women who did not experience any abuse.

CONCLUSIONS

This study indicates that there may be a dose-response association between exposure to childhood abuse or household dysfunction and unintended first pregnancy in adulthood. Additional research is needed to fully understand the causal pathway of this association.

Child sexual abuse as a public health issue: recommendations of an expert panel

Child sexual abuse (CSA) is a widespread problem that has been associated with a variety of negative health outcomes. There has been a call for prevention of first occurrences of CSA. Public health provides a unique framework for conceptualizing and implementing these prevention efforts. This article explains a model of the public health approach to prevention and illustrates the applicability of this model to CSA. The Centers for Disease Control and Prevention convened a panel of experts to advise the agency about raising awareness of CSA as a public health problem. A summary of the recommendations developed by this expert panel is presented.

Domestic violence and sexual abuse in women physicians: associated medical, psychiatric, and professional difficulties

Physicians have been called on to identify victims of domestic violence (DV) and sexual abuse (SA). Few data exist, however, on the prevalence of DV and SA in physicians themselves or on the personal or professional sequelae of such experiences. We determined the reported lifetime prevalence of DV and SA among women physicians and the personal characteristics, health-related factors, and work-related factors associated with these forms of abuse. We used data from the Women Physicians' Health Study, a large (n = 4501 respondents), nationally distributed questionnaire study that included questions on DV and SA histories, personal characteristics, and psychiatric, medical, and work-related histories. We compared the characteristics of women physicians with and without histories of DV or SA. The logistic models indicate that women physicians reporting DV histories (3.7% of the population) were significantly (p < 0.05) less likely to be single and significantly more likely to report depression histories, suicide attempts, substance abuse, current or past cigarette smoking, severe daily stress at home, chronic fatigue syndrome, and DV experienced by their mothers. Women physicians reporting SA histories (4.7% of the population) were significantly more likely to be younger than 60 years, identify themselves as homosexual or bisexual, to have specialized in psychiatry, obstetrics and gynecology, or emergency medicine, and to report histories of depression, suicide attempts, eating disorders, and fair or poor perceived health status. Although the reported lifetime prevalence of DV and SA among women physicians is below other reported figures, such experiences are associated with medical and psychiatric difficulties that could negatively affect them personally and professionally.

Forced sexual intercourse and associated health-risk behaviors among female college students in the United States

This study analyzed data from the 1995 National College Health Risk Behavior Survey (NCHRBS) to assess the prevalence of lifetime rape among female college students and to examine the association between rape and health-risk behaviors. The NCHRBS used a mail questionnaire to assess health-risk behaviors among a nationally representative sample of undergraduate students. Twenty percent of female students reported ever having been forced to have sexual intercourse, most often during adolescence. When analyses controlled for demographic characteristics, female students who had ever been raped were significantly more likely than those who had not to report a wide range of health-risk behaviors. These results highlight a need to improve rape prevention and treatment programs for female adolescents.

Forced sexual intercourse and associated health-risk behaviors among female college students in the United States

This study analyzed data from the 1995 National College Health Risk Behavior Survey (NCHRBS) to assess the prevalence of lifetime rape among female college students and to examine the association between rape and health-risk behaviors. The NCHRBS used a mail questionnaire to assess health-risk behaviors among a nationally representative sample of undergraduate students. Twenty percent of female students reported ever having been forced to have sexual intercourse, most often during adolescence. When analyses controlled for demographic characteristics, female students who had ever been raped were significantly more likely than those who had not to report a wide range of health-risk behaviors. These results highlight a need to improve rape prevention and treatment programs for female adolescents.

The Safe Dates Project: theoretical basis, evaluation design, and selected baseline findings

Approximately 20% of adolescents have experienced violence from a dating partner. The Safe Dates Project tests the effects of a program on the primary and secondary prevention of dating violence among adolescents living in a rural North Carolina county. The program being evaluated aims to prevent dating violence by changing dating violence norms, gender stereotyping, conflict-management skills, help-seeking, and cognitive factors associated with help-seeking. School activities include a theater production, a 10-session curriculum, and a poster contest. Community activities include special services for adolescents in violent relationships and community service provider training. A pretest-posttest experimental design with random allocation of 14 schools to treatment condition was used to test study hypotheses. Data were collected in schools using self-administered questionnaires. Eighty-one percent (n = 1,967) of the eighth- and ninth-graders in the county completed baseline questionnaires, and 91% of those adolescents completed follow-up questionnaires. The sample is 75.9% Caucasian and 50.4% female. Baseline data indicate that 25.4% and 8.0% of this sample have been victims of nonsexual and sexual dating violence, respectively, and 14.0% and 2.0% have been perpetrators of nonsexual and sexual dating violence, respectively. Consistent with other adolescent dating violence studies, both boys and girls report being victims and perpetrators of dating violence. Control and treatment groups are similar at baseline on all demographic, mediating, and outcome variables. Findings suggest that dating violence is prevalent among adolescents and that prevention programs are warranted.

Observed sleep/wakefulness and severity of dementia in an Alzheimer's disease special care unit

BACKGROUND

This study tested the hypothesis that behaviorally defined sleep disturbance among residents in a Special Care Unit (SCU) for Alzheimer's disease (AD) was related to the severity of their dementia. Previously, sleep laboratory studies have reported such relationships when sleep has been recorded polysomnographically over several nights. Observational studies of sleep have not shown such relationships, presumably because of the impression involved in determining sleep/wake state behaviorally.

METHODS

Nightly sleep data based on observations made every two hours by nursing staff for a period of 13 to 18 months were examined for 47 AD residents with a mean age of 80.7 +/- 6.5 years. Level of dementia and functional capacity were assessed with the Mattis Dementia Rating Scale (DRS) and the Katz Activities of Daily Living Scale (ADL).

RESULTS

Data indicated that these SCU residents experienced a moderately disturbed night of sleep an average of 24% +/- 10% of their nights in the facility and a severely disturbed night of sleep on 7% +/- 6% of those nights. More profound dementia was associated with more sleep disturbance; however, incapacity in ADLs, age, gender, and psychoactive medications were unrelated to such disturbances.

CONCLUSIONS

The results indicate that patterns of relationships noted between laboratory-based measures of sleep and variables such as severity of dementia can be detected using behavioral observations of sleep, provided that the number of nights of observation are sufficiently large to offset the measurement error involved in their use.

gamma-Aminobutyric acid concentrations are maintained in anoxic turtle brain

Changes in gamma-aminobutyric acid (GABA) concentrations in the turtle (Pseudemys scripta elegans) brain were studied in situ during prolonged anoxia. With the onset of anoxia, the well-documented rapid increases in GABA found in mammalian brains were not observed in the turtle brain. Although not statistically significant, mean GABA concentrations in the turtle brain were reduced from anesthetized control values during the first 30 min of anoxia. During this initial period brain glutamate content declined. Even after 2 h of nitrogen respiration, GABA in the turtle brain still did not rise above control levels. By the 4th h of anoxia, however, GABA had increased to 147% of control values.

Mock trial jury decisions as a function of adolescent juror guilt and hostility

A fictitious court case involving child abuse was presented to 277 male adolescent jurors (138 college freshmen, means age = 19.25 years, 139 junior high school males, means age = 13.47 years) in an effort to determine if the tendency to deal harshly with alleged criminals is dependent upon certain personality characteristics of adolescent jurors. The Mosher Hostility Guilt Scale and the Siegel Manifest Hostility Scale were used to detect the presence of such trends. The results indicate that older adolescents attributed more of the responsibility for the crime to the defendant and administered less severe sentences than younger adolescent jurors. Hostility guilt and manifest hostility levels were not significantly related to attribution of responsibility for a criminal act; however, Ss scoring high in hostility guilt tended to give significantly shorter sentences, while Ss scoring high in manifest hostility tended to give longer sentences. Implications for adolescent peer practices are discussed.

Determination of creatine phosphate levels in brain tissue by isocratic reverse-phase, ion-paired high-performance liquid chromatography

The utilization of isocratic, reverse-phase, ion-paired high-performance liquid chromatography for analysis of creatine phosphate allows for rapid quantification of multiple samples. Cryogenic sample handling and the addition of ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid as a Ca2+ sequestering agent during perchloric acid extraction enhance maximal recovery of creatine phosphate from brain samples. Peak identification is supported by a complete enzymatic shift with a phosphocreatine kinase, hexokinase, and glucose-6-phosphate dehydrogenase system.

Defendant characteristics and judgment behaviors of adolescent mock jurors

Fictitious court cases involving child abuse were presented to 140 male undergraduates and 140 male junior high school students to determine if the tendency to deal harshly with alleged criminals is dependent upon certain defendant characteristics. Results indicate that younger adolescent jurors give longer sentences than older adolescent jurors, and male defendants receive longer sentences than female defendants. While no significant main effects for case content were found, younger jurors gave longer sentences and attributed more responsibility to a parent who beat his/her child, while older adolescent jurors attributed more responsibility and prescribed longer sentences to a parent who burned the child. Implications for future research with adolescent jurors are discussed.

Coordination of perspectives: the importance of stimulus dimensionality

An evaluation of the importance of the dimensionality of the spatial stimuli in a coordination of perspectives task is presented. It was hypothesized that using three-dimensional comparison stimuli and two-dimensional choice stimuli might result in the tapping of different cognitive skills than when both sets of stimuli are two-dimensional. Children (N = 96) aged between 5 and 12 years as well as college students (n = 24) were tested with either two-dimensional or three-dimensional comparison stimuli and two-dimensional choice stimuli. The lowest error rates for all except the kindergarten groups were found in the two-dimensional condition. It was concluded that the three-dimensional condition may have created a cognitive overload that lessened the likelihood of making correct perspective-taking judgments.