These findings support hypoglutamatergic hypotheses of schizophrenia and suggest a novel approach for the pharmacotherapy of negative symptoms associated with this illness.

Neighborhood type was a predictor of cognitive impairment. Education affected MMSE scores similarly in both ethnic groups. MMSE scores <24, indicative of cognitive impairment, were uniformly associated with functional impairment in both the Mexican Americans and European Americans. Among older Mexican Americans, MMSE-classified cognitive impairment was significantly associated with poorer performance on timed tasks with varying levels of cognitive demand independent of other correlates. A similar pattern of association was observed in European Americans. Thus, the MMSE appears to be a valid indicator of cognitive impairment in survey research in both older Mexican Americans and European Americans.

Two instruments for the detection of hearing impairment, the Welch-Allyn audioscope (Welch-Allyn Inc, Skaneateles Falls, NY) and the Hearing Handicap Inventory for the Elderly--Screening Version (HHIE-S), were validated against pure tone audiometry in 178 patients over 65 years old screened in primary care practice. The prevalence of hearing impairment in this sample was 30%. The audioscope yielded reproducible results in the physicians' offices and a hearing center. The sensitivity of the audioscope was 94% in both locations, while its specificity was 90% in the hearing center and 72% in the physicians' offices. The HHIE-S yielded reproducible results between the two test locations. An HHIE-S score from 0 to 8 resulted in a likelihood ratio of 0.36 (95% confidence interval, 0.19 to 0.68), and a score of 26 or more yielded a likelihood ratio of 12.00 (95% confidence interval, 2.62 to 55.00) for predicting the presence of hearing impairment. Used together, the two instruments had a test accuracy of 83%. The audioscope and HHIE-S are valid, reliable, inexpensive tools for detecting hearing impairment in the elderly.