Two reports have been published suggesting an association between the personality trait of novelty seeking and the DRD4*7R allele at the D4 dopamine-receptor locus (with heterozygotes or homozygotes for DRD4*7R having higher novelty seeking). We studied novelty seeking and four coding-sequence polymorphisms affecting protein structure in the D4 dopamine-receptor gene (DRD4) in a sample of 341 American subjects, of whom 224 are of primarily European ancestry and 117 are of primarily African ancestry. These subjects had diagnoses of substance dependence or personality disorder (PD) or were screened to exclude major psychiatric diagnosis. We found that, although the substance-dependent subjects had significantly higher novelty seeking than the control and PD subjects, they did not differ in DRD4*7R allele frequency. There was no association between any DRD4 polymorphism and novelty seeking in any population or diagnostic group, except for a significant association between the DRD4*7R allele and lower novelty seeking among European American females and African American substance abusers. The novelty seeking of subjects heterozygous for a null mutation did not differ from that of subjects with two functional alleles. We conclude that the most likely explanation of these results is that the DRD4 VNTR does not influence directly the trait of novelty seeking, in these samples.

As might be expected, the OCDS questions on drinking behavior predict subsequent drinking behavior. However, the instrument does not appear to provide a general measure of alcohol-related illness. The utility of the OCDS in studies of alcoholism treatment outcome requires clearer definition.

To evaluate the validity of 2 self-report methods for estimating cocaine use, Timeline Follow-Back (TLFB) and weekly calendar reports from 65 patients with a cocaine use disorder were compared with urine drug test results. The TLFB showed fair to moderate validity, and the weekly calendar showed moderate to high validity in measuring the frequency of cocaine use. Similar results were obtained when the self-report measures were used to time specific cocaine use episodes. In addition to evidence for superiority of the weekly calendar, the validity of self-reports was inversely related to the percentage of positive urine test results. Furthermore, there was some evidence that validity increased as the time window over which the comparisons were drawn increased. Given the central role of self-reports in the clinical and research evaluation of drug use, factors affecting their validity warrant further investigation.

We conducted a cross-sectional study to determine the distribution of cognitive functioning as measured by the Mini-Mental State Examination (MMSE) among a sample of Hispanic and non-Hispanic White (NHW) residents from two counties in rural, southern Colorado. Residents aged 60 years and older (N = 1,360) were administered the full MMSE, a sociodemographic and medical interview. Protocols were developed to administer the MMSE equitably in both ethnic groups. Younger Hispanics tended to be categorized as severely impaired more than similarly aged NHWs (OR at age 70 = 4.14), however, older Hispanics and NHWs performed similarly after adjusting for education and gender (OR at age 90 = 1.00). The use of a modified MMSE scale that removed the ethnic bias demonstrated that NHWs and Hispanics had similar levels of severe impairment after full adjustment (OR = 0.93). Given the widespread use of the MMSE, these findings indicate the need for further validation of this instrument.

No abstract