Use of inpatient psychiatric care at a VA medical center after implementation of a prospective payment system.

A retrospective audit of patients' utilization of inpatient psychiatric care at a Department of Veterans Affairs medical center before and after implementation of a prospective payment system compared patterns of utilization by chronic and nonchronic patients. It also examined changes over time in the size of the two groups, total number of bed days used, mean number of admissions, mean length of stay, and mean cumulative two-year length of stay. Four years after implementation of the prospective payment system, chronic patients constituted 3 percent of the patient population but used 15.2 percent of all bed days. Both chronic and nonchronic patients had a similar decrease in mean length of stay over the period, but chronic patients' mean number of admissions rose by more than 70 percent. The mean cumulative two-year length of stay of chronic patients remained stable over the period while that of the nonchronic patients decreased by 33.2 percent.     

Data‐driven analyses of an fMRI study of a subject experiencing phosphenes

Purpose:

To compare two data‐driven methods of statistical image analysis, principal and independent component analysis (PCA, ICA), in identifying neural networks related to the transient occurrence of phosphenes experienced by a female patient subsequent to a brain infarct.

Materials and Methods:

An initial functional magnetic resonance imaging (fMRI) session consisted of two acquisitions: one of the patient experiencing phosphenes and a second responding to a well‐defined visual stimulation paradigm. A second fMRI session 6 months later, when the patient no longer experienced phosphenes, consisted of an acquisition in which no stimulation was presented. Analysis of correlations between the temporal expression coefficients and models of the hemodynamic response identified salient components. Spectral analysis confirmed the identification. The phosphene model was based solely on the subjective report of the patient.

Results:

Both methods revealed occipital cortical and subcortical areas known to be sites for visual information‐processing during stimulation, as did SPM. In addition, higher‐order visual areas such as the precuneus and the lateral parietal cortex were implicated in the PCA of the phosphenes.

Conclusion:

The analyses suggest the capability of data‐driven approaches to identify the brain structures involved in these transient, spontaneous visual events. J. Magn. Reson. Imaging 2010;31:821–828. ©2010 Wiley‐Liss, Inc.     

The role of acetaldehyde in upper digestive tract cancer in alcoholics

Chronic excessive alcohol consumption is the strongest risk factor for upper aerodigestive tract (UADT) cancer. Multiple mechanisms are involved in alcohol-associated cancer development of the UADT, including acetaldehyde (AA) effects. AA is toxic, mutagenic, and carcinogenic. Evidence of the role of AA in alcohol-associated carcinogenesis derived from genetic linkage studies in alcoholics. Polymorphism or mutation in genes coding for AA generation or detoxification enzymes are associated with increased cancer risk. It has been clearly shown in Asians that individuals carrying the acetaldehyde dehydrogenase 2*2 (ALDH2*2) allele have a significantly increased cancer risk when they consume alcohol. In Caucasians, alcohol dehydrogenase 1*1 (ADH1C*1) allele encodes for an alcohol dehydrogenase (ADH) isoenzyme, which produces 2.5 times more AA than the corresponding allele ADH1C*2. The authors found that the ADH1C*1 allele frequency and rate of homozygosity was significantly associated with an increased risk for alcohol-related cancer. AA seems to be an important factor in alcohol-associated carcinogenesis of the UADT.