Impaired glucose tolerance in first-episode drug-naïve patients with schizophrenia: relationships with clinical phenotypes and cognitive deficits.

BACKGROUND: Schizophrenia patients have a higher prevalence of type 2 diabetes mellitus with impaired glucose tolerance (IGT) than normals. We examined the relationship between IGT and clinical phenotypes or cognitive deficits in first-episode, drug-naïve (FEDN) Han Chinese patients with schizophrenia. METHOD: A total of 175 in-patients were compared with 31 healthy controls on anthropometric measures and fasting plasma levels of glucose, insulin and lipids. They were also compared using a 75 g oral glucose tolerance test and the homeostasis model assessment of insulin resistance (HOMA-IR). Neurocognitive functioning was assessed using the MATRICS Consensus Cognitive Battery (MCCB). Patient psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). RESULTS: Of the patients, 24.5% had IGT compared with none of the controls, and they also had significantly higher levels of fasting blood glucose and 2-h glucose after an oral glucose load, and were more insulin resistant. Compared with those patients with normal glucose tolerance, the IGT patients were older, had a later age of onset, higher waist or hip circumference and body mass index, higher levels of low-density lipoprotein and triglycerides and higher insulin resistance. Furthermore, IGT patients had higher PANSS total and negative symptom subscale scores, but no greater cognitive impairment except on the emotional intelligence index of the MCCB. CONCLUSIONS: IGT occurs with greater frequency in FEDN schizophrenia, and shows association with demographic and anthropometric parameters, as well as with clinical symptoms but minimally with cognitive impairment during the early course of the disorder.

Medication-taking behaviours in young adults with schizophrenia: a pilot study.

The purpose of this prospective and observational study was to explore medication-taking behaviours in community-based young adults with schizophrenia using an electronic monitoring system and patient self-report questionnaires. The Medication Event Monitoring System (MEMS®), the Index for Medication Adherence (IMA) and the Brief Evaluation of Medication Influences and Beliefs (BEMIB) measured medication-taking behaviours. Data were collected at baseline, 4 and 8 weeks. Descriptive statistics were used in analysis. A total of 11 subjects were recruited; one dropped out. Five were male, and five were female. Average age was 32.64 (SD = 5.70) years. Four (40%) were White people; six (60%) were non-White people. The average number of medications treating schizophrenia was 1.9 (SD = 0.57). MEMS® identified 71.77% (SD = 30.47) dose adherence and 55.92% (SD = 31.27) day adherence. Most subjects took medications irregularly (early, late or missing). The BEMIB demonstrated that 50%, 20% and 30% of subjects considered themselves to be adherent to their medications at baseline, 4 weeks and 8 weeks, while the IMA reported 90%, 90% and 80% at baseline, 4 weeks and 8 weeks, respectively. Regarding the observed discrepancies between patients' reports and their actual medication-taking behaviours, clinical implications were discussed. Effective interventions improving medication adherence in schizophrenia are needed for practice and for future studies.

Impairments in frontal cortical gamma synchrony and cognitive control in schizophrenia.

A critical component of cognitive impairments in schizophrenia can be characterized as a disturbance in cognitive control, or the ability to guide and adjust cognitive processes and behavior flexibly in accordance with one's intentions and goals. Cognitive control impairments in schizophrenia are consistently linked to specific disturbances in prefrontal cortical functioning, but the underlying neurophysiologic mechanisms are not yet well characterized. Synchronous gamma-band oscillations have been associated with a wide range of perceptual and cognitive processes, raising the possibility that they may also help entrain prefrontal cortical circuits in the service of cognitive control processes. In the present study, we measured induced gamma-band activity during a task that reliably engages cognitive control processes in association with prefrontal cortical activations in imaging studies. We found that higher cognitive control demands were associated with increases in induced gamma-band activity in the prefrontal areas of healthy subjects but that control-related modulation of prefrontal gamma-band activity was absent in schizophrenia subjects. Disturbances in gamma-band activity in patients correlated with illness symptoms, and gamma-band activity correlated positively with performance in control subjects but not in schizophrenia patients. Our findings may provide a link between previously reported postmortem abnormalities in thalamofrontocortical circuitry and alterations in prefrontal activity observed in functional neuroimaging studies. They also suggest that deficits in frontal cortical gamma-band synchrony may contribute to the cognitive control impairments in schizophrenia.

Regraft kidney transplant survival.

The salient features of one-year regraft transplant survival are as follows: 1. The effect of cyclosporine is less (about 7% increase in one-year graft survival) on regrafted patients than on first grafts. 2. In general we saw a HLA antigen matching effect in cyclosporine- and noncyclosporine-treated retransplant patients. 3. Patients who received living-related HLA two-haplotype matched kidneys did equally as well as a first or regraft recipient. 4. Transfusions seemed to have a minimal effect on regraft survival. 5. It is more important to match in patients who have PRA and the matching benefits translate into 61% and 75% one-year graft survival for zero DR and zero B,DR mismatched regraft patients, respectively. 6. In regrafts, female donor kidneys resulted in 15% lower one-year graft survival than male donor kidneys. 7. Retransplant patients from fair centers showed a significant 13% increase in one-year graft survival with cyclosporine. 8. Cold ischemia time, diabetes, and kidneys used locally or shipped had little effect on the regraft one-year survival. 9. The initial function of the retransplant kidney had a very large effect on the final one-year graft outcome of that kidney and was independent of the use of cyclosporine patients having a functioning kidney at one month had 75% and 72% one-year regraft survival with and without cyclosporine treatment, respectively. Patients having a nonfunctioning kidney at one month had 5% and 8% one-year regraft survival with and without cyclosporine treatment, respectively. 10. Responder and nonresponder classifications as defined by the duration of the first graft resulted in a 10 to 15% difference in regraft survival. 11. The effect of HLA-A,B matching was very strong in responder patients, i.e., there was a 32% difference in one-year regraft survival between zero mismatch and more than two antigens of mismatch. In nonresponder patients, the effect of HLA-A,B matching was only 5%. For HLA-DR locus matching, the difference was 12% for responders and 6% for nonresponders. 12. Cyclosporine use showed about a 10% increase in graft survival in responders and nonresponders. 13. Responder classification was also possible by separating patients who had initial function but no function at one month (responders) from those with function at one month (nonresponders).

Regrafts.

1. One-year patient survival rates improved markedly year by year for regrafted kidney patients reaching 93% in 1986, as compared with 96% in first grafts. 2. The graft survival rate of regrafts also showed steady improvement, but was not benefited by the introduction of CsA as much as in first grafts. One-year graft survival rate was 63% for regrafts in 1986. 3. The functional graft survival was higher with advancing recipient age in first grafts, but remained essentially constant regardless of age in regrafts. We interpret this to mean that older patients have depressed immunologic capability to reject first grafts, but those immunized patients by rejecting a first graft have undiminished reactivity. 4. A high graft survival rate of 68% at one-year was observed for patients who had been sensitized before their first transplant but lost their antibodies before the second transplant. One-year graft survival of those who were not sensitized before both first and second grafts was 60%. 5. The duration of first grafts significantly influences the outcome of second grafts (p less than 0.00001). The highest graft survival was obtained in recipients who had functioning first grafts for more than 2 years (69% at one year), followed by those for recipients whose grafts had functioned for one to 2 years, 6-12 months, and 3-6 months. Patients who lost their first grafts within 3 months had the lowest graft survival rate (44% at one year). 6. The time interval had an influence on the outcome of second grafts.(ABSTRACT TRUNCATED AT 250 WORDS)

Reliability and dimensionality of judgments of visually textured materials.

We extended perceptual studies of the Brodatz set of textured materials. In the experiments, texture perception for different texture sets, viewing distances, or lighting intensities was examined. Subjects compared one pair of textures at a time. The main task was to rapidly rate all of the texture pairs on a number scale for their overall dissimilarities first and then for their dissimilarities according to six specified attributes (e.g., texture contrast). The implied dimensionality of perceptual texture space was usually at least four, rather than three. All six attributes proved to be useful predictors of overall dissimilarity, especially coarseness and regularity. The novel attribute texture lightness, an assessment of mean surface reflectance, was important when viewing conditions were wide-ranging. We were impressed by the general validity of texture judgments across subject, texture set, and comfortable viewing distances or lighting intensities. The attributes are nonorthogonal directions in four-dimensional perceptual space and are probably not narrow linear axes. In a supplementary experiment, we studied a completely different task: identifying textures from a distance. The dimensionality for this more refined task is similar to that for rating judgments, so our findings may have general application.