Psychological factors in people at ultra-high risk of psychosis: comparisons with non-patients and associations with symptoms

BACKGROUND: There have been recent advances in the ability to identify people at high risk of developing psychosis. This has led to interest in the possibility of preventing the development of psychosis and provides the opportunity to investigate psychological mechanisms that may confer vulnerability to psychosis. METHOD: Fifty-eight patients at ultra-high risk of developing a first episode of psychosis were compared with 56 non-patients matched for age and occupational status on measures of meta-cognition, schizotypal traits, dysfunctional attitudes and distress. RESULTS: Analyses of covariance revealed that people at high risk of developing psychosis scored higher on measures of cognitive vulnerability, including negative meta-cognitive beliefs, beliefs about rejection and criticism from others, and discrepancies in self-perception, schizotypal traits and general mental distress. Correlational analyses revealed that negative meta-cognitive beliefs, dysfunctional attitudes and beliefs about rejection and criticism from others were positively associated with several dimensions of symptomatology in at-risk mental states (ARMS) patients. CONCLUSIONS: Cognitive and personality factors appear to characterize people at high-risk of developing psychosis and are associated with their distressing experiences. The clinical implications of these findings are discussed.     

Epidemiology of Spotted Fever Group and Typhus Group Rickettsial Infection in the Amazon Basin of Peru

A seroprevalence study for IgG antibodies against spotted fever group (SFGR) and typhus group (TGR) Rickettsia among humans and domestic pets was conducted in the city of Iquitos, located in the Amazon basin of Peru. Of 1,195 human sera analyzed, 521 (43.6%) and 123 (10.3%) were positive for SFGR and TGR antibodies, respectively. District of residence and participant age were associated with antibody positivity for both groups, whereas rodent sightings in the home were associated with TGR antibody positivity. Of the 71 canines tested, 42 (59.2%) were positive for SFGR antibodies, and two (2.8%) were positive for TGR antibodies; one active SFGR infection was detected by polymerase chain reaction. An uncharacterized SFGR species was detected in 95.9% (71/74) of Ctenocephalides felis pools collected from domestic pets. These data suggest that rickettsial transmission is widespread in Iquitos. Rickettsia species should be further explored as potential causes of acute febrile illnesses in the region.     

A measurement of the efficacy of nosocomial infection control using the 95 per cent confidence interval for infection rates

From 1981 through 1985, the authors studied the changes in monthly nosocomial infection rates at the University of Virginia Hospital in Charlottesville, Virginia using the 95% confidence interval for infection rates as a marker of the efficacy of infection control activities. For a 99-month baseline period, monthly infection rates were calculated and the 95% confidence interval was established. In the 60 study months, each monthly rate was compared with the 95% confidence interval for that particular month. At the end of each study year, the monthly infection rates were incorporated into the existing confidence interval. Of 60 monthly rates during the study period, 30 were below the confidence interval (p less than 0.00001), two were above the confidence interval (p = 0.23), and 28 were within the confidence interval. Since there was no reduction in surveillance activity, patient case-mix index, or laboratory sensitivity for organism recovery, these results suggest that monthly nosocomial infection rates at this hospital have decreased when compared with the baseline period. The use of the 95% confidence interval may provide a measure of the efficacy of infection control activities, suggest temporal intervals requiring more intensive infection surveillance, and provide a method for examining the variability in monthly infection rates.     

CVA3 Adherence to Hypertension Therapy: The Effect of Initial Drug Choice

Health-care case management places pressure on decision makers to adopt treatment strategies that promote economic efficiency and hence profitability. Traditional costeffectiveness analysis (CEA), where the objective is to calculate cost-effectiveness ratios, can better inform decision making in markets where prices and efficacy vary widely. However, the threshold at which a given therapy becomes economically efficient relative to competing therapies is not evident from cost-effictiveness ratios alone.
OBJECTIVE: To illustrate the use of spatial techniques for identifying efficient treatment options, using statin therapy in secondary prevention of coronary heart disease (CHD) as a case study.
METHODS: We used a Markov model of CHD epidemiology and treatment to estimate cost-effectivness of 13 statin regimens versus no therapy in secondary prevention of CHD. Comparative efficacy was assessed using data from a recent trial (CURVES) that included these regimens. Patients were assumed to have a history of CHD with risk factors similar to those observed in the trial. CHD event risk was estimated using new subsequent-event risk equations from the Framingham Heart Study. Effectiveness was measured alternatively as gain in life expectancy and CHD events averted.
RESULTS: At usual starting doses, atorvastatin therapy provided the largest life expectancy gain and CHD event avoidance at the lowest cost per life-year gained ($12,900 and $23,400 for men and women, respectively), followed by simvastatin ($17,700 and $31,700), lovastatin ($18,800 and $33,700), pravastatin ($22,600 and $40,200), and fluvastatin ($23,800 and $42,000). Any desired level of effectiveness can be obtained at lowest cost with atorvastatin.
CONCLUSION: Economic efficiency is enhanced when atorvastatin is used to treat some or all patients requiring statin therapy in secondary prevention of CHD.     

Huntington disease in County Donegal: epidemiological trends over four decades.

The prevalence rate of Huntington disease in County Donegal between 1961 and 1991 showed a decrease from 4.4 to 1.6 per 100,000 population. Emigration and reduction in family size probably account for the progressive decline in prevalence. Over the same time period in the rest of Europe, prevalence has declined only gradually, or has remained static.     

A soluble activin type IIB receptor improves function in a mouse model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurologic disease characterized by progressive weakness that results in death within a few years of onset by respiratory failure. Myostatin is a member of the TGF-β superfamily that is predominantly expressed in muscle and acts as a negative regulator of muscle growth. Attenuating myostatin has previously been shown to produce increased muscle mass and strength in normal and disease animal models. In this study, a mouse model of ALS (SOD1^G93A transgenic mice) was treated with a soluble activin receptor, type IIB (ActRIIB.mFc) which is a putative endogenous signaling receptor for myostatin in addition to other ligands of the TGF-β superfamily. ActRIIB.mFc treatment produces a delay in the onset of weakness, an increase in body weight and grip strength, and an enlargement of muscle size whether initiated pre-symptomatically or after symptom onset. Treatment with ActRIIB.mFc did not increase survival or neuromuscular junction innervation in SOD1^G93A transgenic mice. Pharmacologic treatment with ActRIIB.mFc was superior in all measurements to genetic deletion of myostatin in SOD1^G93A transgenic mice. The improved function of SOD1^G93A transgenic mice following treatment with ActRIIB.mFc is encouraging for the development of TGF-β pathway inhibitors to increase muscle strength in patients with ALS.     

Cultured motor neurons possess calcium-permeable AMPA/kainate receptors

We examined the biology of AMPA/kainate-induced motor neuron degeneration using dissociated spinal cord cultures and motor neuron-specific antibodies which enable characterization of individual motor neurons in culture. Cobalt, which is thought to pass through Ca2+-permeable AMPA/kainate receptors following kainate exposure, labeled motor neurons in spinal cord cultures. The analysis of AMPA subunit distribution in dissociated motor neurons revealed a unique pattern of glutamate receptor (GluR) subunits in those cells; the GluR1 subunit was found in all spinal cord neurons, but the GluR2 subunit was not found in identified dissociated motor neurons. These data suggest that selective sensitivity of motor neurons to non-NMDA receptor activation is due, at least in part, to the presence of Ca2+-permeable AMPA/kainate receptors.