Publications

Although fecal immunochemical tests (FITs) have been used for colorectal cancer (CRC) screening in several countries for years, this has not been the case in the United States. The reasons for this are multifactorial, but if the United States hopes to increase screening rates, the evidence is in regarding FIT's benefits and potential. A publication in this issue of the American Journal of Gastroenterology provides "gold standard" evidence of its superiority over the standard guaiac test and opens opportunities for investigators to discover the most effective uses of this test for population screening.

Ventricular tachycardia (VT) may be monomorphic or polymorphic. Although commonly related to organic heart disease, a significant percentage of VTs are idiopathic (occurring in patients with otherwise normal hearts). Correctly identifying the substrate and mechanism of the tachycardia is essential for proper management. Although therapy for monomorphic VT associated with structural heart disease focuses on tachycardia suppression and reduction of sudden cardiac death (SCD) risk, idiopathic monomorphic VT generally does not entail an increased risk of SCD and treatment is aimed primarily at symptom reduction. Polymorphic VT associated with ischemia or an acquired precipitant that prolongs the QT interval should prompt reversal of underlying cause, in contrast to the congenital arrhythmia syndromes, which demand genetic testing to define the underlying problem. This review describes the diagnosis, mechanisms, etiology, and management of monomorphic and polymorphic VT, with attention to recent advances in biological understanding and the most current therapeutic recommendations.

Although kidney disease has been a recognized complication of HIV infection since the beginning of the HIV epidemic, its epidemiology, underlying causes and treatment have evolved in developed countries where HAART has been widely available. HIV-associated nephropathy and HIV immune complex-mediated kidney disease were the prominent renal diagnoses in the earlier period of the HIV epidemic. While HIV immune complex-mediated kidney disease remains a common finding among HIV-infected individuals with kidney disease, the incidence of HIV-associated nephropathy has been diminishing in developed countries. The role of the metabolic effects of long-term HAART exposure and nephrotoxicity of certain antiretroviral medications on the development and progression of chronic kidney disease is now of increasing concern. The long-term clinical implications of acute kidney injury among HIV-infected persons are increasingly recognized. Kidney disease in HIV-infected persons continues to be a major risk factor for morbidity and mortality in this patient population; therefore, early recognition and treatment of kidney disease are imperative in lessening the impact of kidney disease on the health of HIV-infected individuals. This review focuses on recent developments and ongoing challenges in the understanding, diagnosis and management of HIV-related kidney disease.

BACKGROUND

Patient handling is a major risk factor for musculoskeletal (MS) injury among nurses. The aims of the study were to describe nurses' work behaviors related to safe patient handling and identify factors influencing their safe work behaviors, including the use of lifting equipment.

METHODS

A cross-sectional study using a mailed questionnaire with a nationwide random sample of 361 critical care nurses. Nurses reported on the physical, psychosocial, and organizational characteristics of their jobs and on their MS symptoms, risk perception, work behaviors, and demographics. Hierarchical multiple linear regression analyses were used to identify significant factors.

RESULTS

More than half of participants had no lifting equipment on their unit, and 74% reported that they performed all patient lift or transfer tasks manually. Significant factors for safer work behavior included better safety climate, higher effort-reward imbalance, less overcommitment, greater social support, and day shift work. Physical workload, personal risk perception, or MS symptom experiences were not associated with safe work behavior.

CONCLUSIONS

Safe work behaviors are best understood as socio-cultural phenomena influenced by organizational, psychosocial, and job factors but, counter to extant theories of health behaviors, do not appear to be related to personal risk perception. Management efforts to improve working conditions and enhance safety culture in hospitals could prove to be crucial in promoting nurses' safe work behavior and reducing risk of MS injury.

Laboratory and epidemiologic evidence suggests that pathogen-specific factors may affect multidrug-resistant (MDR) tuberculosis (TB) transmission and pathogenesis. To identify demographic and clinical characteristics of MDR TB case clustering and to estimate the effect of specific isoniazid resistance-conferring mutations and strain lineage on genotypic clustering, we conducted a population-based cohort study of all MDR TB cases reported in California from January 1, 2004, through December 31, 2007. Of 8,899 incident culture-positive cases for which drug susceptibility information was available, 141 (2%) were MDR. Of 123 (87%) strains with genotype data, 25 (20%) were aggregated in 8 clusters; 113 (92%) of all MDR TB cases and 21 (84%) of clustered MDR TB cases occurred among foreign-born patients. In multivariate analysis, the katG S315T mutation (odds ratio 11.2, 95% confidence interval 2.2-Yen; p = 0.004), but not strain lineage, was independently associated with case clustering.

AIMS

Individuals with asthma may be at increased risk of depression, but few studies have identified precursors to the onset of depression. The study goal was to identify risk factors for depression onset among a community-based sample of adults with asthma.

METHODS

Data were obtained from three telephone interviews conducted at 2-yearly intervals on a longitudinal cohort of adults with asthma (n=439). The Center for Epidemiologic Studies Depression scale (CESD) was used to measure depressive symptoms. Multiple regression analyses tested associations of sociodemographic and health-related variables with depression prevalence (cross-sectional analyses) and incident depression (longitudinal analyses).

RESULTS

15% of subjects were classified as "depressed" (CESD> or =23) at each interview. Individuals depressed at baseline were more likely to drop out (OR=1.76 [95% CI 1.05, 2.96]). Low perceived control of asthma (measured with the Perceived Control of Asthma Questionnaire [PCAQ]) exhibited the most consistent association with depression. Lower PCAQ was cross-sectionally associated with depression (OR=0.51 per 0.5 SD difference in PCAQ [0.35, 0.75]). Onset of depression was noted in 38 individuals. Decrease in perceived control at follow-up was associated with depression onset (OR=7.47 [2.15, 26.01]).

CONCLUSIONS

Low perceived control of asthma predicted depression onset among adults with asthma. This risk factor may respond to self-management education.

RATIONALE

Although cigarette smoking is the most important cause of chronic obstructive pulmonary disease (COPD), a substantial proportion of COPD cases cannot be explained by smoking alone.

OBJECTIVES

To evaluate the risk factors for COPD besides personal cigarette smoking.

METHODS

We constituted an ad hoc subcommittee of the American Thoracic Society Environmental and Occupational Health Assembly. An international group of members was invited, based on their scientific expertise in a specific risk factor for COPD. For each risk factor area, the committee reviewed the literature, summarized the evidence, and developed conclusions about the likelihood of it causing COPD. All conclusions were based on unanimous consensus.

MEASUREMENTS AND MAIN RESULTS

The population-attributable fraction for smoking as a cause of COPD ranged from 9.7 to 97.9%, but was less than 80% in most studies, indicating a substantial burden of disease attributable to nonsmoking risk factors. On the basis of our review, we concluded that specific genetic syndromes and occupational exposures were causally related to the development of COPD. Traffic and other outdoor pollution, secondhand smoke, biomass smoke, and dietary factors are associated with COPD, but sufficient criteria for causation were not met. Chronic asthma and tuberculosis are associated with irreversible loss of lung function, but there remains uncertainty about whether there are important phenotypic differences compared with COPD as it is typically encountered in clinical settings.

CONCLUSIONS

In public health terms, a substantive burden of COPD is attributable to risk factors other than smoking. To prevent COPD-related disability and mortality, efforts must focus on prevention and cessation of exposure to smoking and these other, less well-recognized risk factors.

PURPOSE

Personalized medicine is changing oncology practice and challenging decision making. A key challenge is the limited clinical evidence for many personalized medicine technologies. We describe the strategies private payers employed to develop coverage policy for personalized medicine using the example of the 21-gene assay in breast cancer.

METHODS

We examined the coverage policies of six private payers for the 21-gene assay. We then interviewed senior executives (n = 7) from these payers to elucidate factors informing coverage decisions. We additionally focused on the timing of payer decisions compared with the timing of evidence development, measured by publication of primary studies and relevant clinical guidelines.

RESULTS

The 21-gene assay became commercially available in 2004. The interviewed payers granted coverage between 2005 and 2008. Their policies varied in structure (eg, whether prior authorization was required). All payers reported clinical evidence as the most important factor in decision making, but all used some health care system factors (eg, physician adoption or medical society endorsement) to inform decision making as well. Payers had different perceptions about the strength of clinical evidence at the time of the coverage decision.

CONCLUSION

Coverage of the 21-gene assay is currently widespread, but policies differ in timing and structure. A key approach private payers use to develop coverage policies for novel technologies is considering both clinical evidence and health care system factors. Policy variation may emerge from the range of factors used and perception of the evidence. Future research should examine the role of health care system factors in policy development and related policy variations.