DXA-Generated Z-Scores and T-Scores May Differ Substantially and Significantly in Young Adults

Central dual-energy X-ray absorptiometry (DXA) is the gold standard for non-invasive measurement of bone mineral density (BMD). Using this value and subject demographics, DXA software calculates T-scores and Z-scores. Professional society guidelines for the management of osteoporosis are based on T-scores and Z-scores, rather than on the actual BMD value. Although one expects T-scores and Z-scores to be very similar in young men and women for any given BMD measurement, little literature exists on this issue. Our clinical experience shows that some younger adult individuals (premenopausal women and men younger than 50 yr) have larger than expected difference between their DXA T-score and Z-score. This cross-sectional study evaluates the extent of this discordance between Z-scores and T-scores in a sample of 4275 men and women aged 20–49 yr. All subjects were scanned by central DXA using equipment manufactured by GE Lunar, GE, Madison, WI, or Hologic, Inc., Bedford, MA. Significant differences between Z-scores and T-scores were seen within individuals at the lumbar spine, total hip, femoral neck, and trochanter (p value < 0.001) for both DXA systems. Although these differences were less than half a standard deviation (SD) in most instances, the magnitude of difference was substantial at times, being 1 or more SD in up to 11% of cases (range: −1.95 to +1.54 SD). The smallest differences were seen at the total hip and the largest differences were seen at the femoral neck for both technologies. This is in part because there is no single standard Z-score definition, resulting in different methods of calculation across, and even within, DXA manufacturers. Standardization of Z-score definition and method of calculation is indicated. DXA Z-scores should be interpreted with caution in men and women aged 20–50 yr.     

Neocortical gray matter volume in first-episode schizophrenia and first-episode affective psychosis: a cross-sectional and longitudinal MRI study.

BACKGROUND: Overall neocortical gray matter (NCGM) volume has not been studied in first-episode schizophrenia (FESZ) at first hospitalization or longitudinally to evaluate progression, nor has it been compared with first-episode affective psychosis (FEAFF). METHODS: Expectation-maximization/atlas-based magnetic resonance imaging (MRI) tissue segmentation into gray matter, white matter (WM), or cerebrospinal fluid (CSF) at first hospitalization of 29 FESZ and 34 FEAFF, plus 36 matched healthy control subjects (HC), and, longitudinally approximately 1.5 years later, of 17 FESZ, 21 FEAFF, and 26 HC was done. Manual editing separated NCGM and its lobar parcellation, cerebral WM (CWM), lateral ventricles (LV), and sulcal CSF (SCSF). RESULTS: At first hospitalization, FESZ and FEAFF showed smaller NCGM volumes and larger SCSF and LV than HC. Longitudinally, FESZ showed NCGM volume reduction (-1.7%), localized to frontal (-2.4%) and temporal (-2.6%) regions, and enlargement of SCSF (7.2%) and LV (10.4%). Poorer outcome was associated with these LV and NCGM changes. FEAFF showed longitudinal NCGM volume increases (3.6%) associated with lithium or valproate administration but without clinical correlations and regional localization. CONCLUSIONS: Longitudinal NCGM volume reduction and CSF component enlargement in FESZ are compatible with post-onset progression. Longitudinal NCGM volume increase in FEAFF may reflect neurotrophic effects of mood stabilizers.     

Accentuating the positive??: An analysis of teacher verbalizations with young children

One of the primary influences on the quality of child care classrooms is teacher behavior, and a critical component of teacher behavior is verbal communication. This study examined the quality of teacher verbalizations with young children in preschool classrooms. Nineteen of the teachers were enrolled in community college courses in early childhood education and child development between pre- and posttesting and fifteen were not. Results indicated that although there was significant improvement on a measure of global classroom quality for those teachers involved in college coursework, teacher verbalizations did not become more appropriate. These findings are discussed in light of current teacher education programs and policy issues.     

Hepatocyte paraffin 1 antibody does not distinguish primary ovarian tumors with hepatoid differentiation from metastatic hepatocellular carcinoma.

Anti-hepatocyte antibody, hepatocyte paraffin 1, is a monoclonal antibody that is highly specific for normal and neoplastic hepatocytes and that can differentiate hepatocytic from nonhepatocytic tumors. This marker has been rarely studied in extra-hepatic tumors and to our knowledge has not been investigated in ovarian tumors with hepatoid differentiation. We studied hepatocyte paraffin 1 immunoreactivity in a series of ovarian hepatoid carcinomas, ovarian hepatoid yolk sac tumors (YSTs), and hepatocellular carcinomas metastatic to the ovary to assess the potential utility of hepatocyte paraffin 1 in differential diagnosis. Hepatocyte paraffin 1 positivity was seen in three of seven ovarian hepatoid carcinomas, five of eight hepatoid yolk sac tumors, and six of eight metastatic hepatocellular carcinomas. The extent of positivity ranged from <25% to >50% of the tumor cells. There was strong coarsely granular cytoplasmic staining in all three tumor types without a distinctive staining pattern in any group. The degree of hepatic differentiation correlated with hepatocyte paraffin 1 positivity in the three groups: 83% of the well differentiated tumors, 50% of the moderately differentiated tumors, and none of the poorly differentiated tumors were positive. All ovarian hepatoid carcinomas were either immunoreactive for alpha-fetoprotein or had an elevated serum alpha-fetoprotein level; more than half of these tumors were hepatocyte paraffin 1 negative. All but one hepatocyte paraffin 1 negative hepatoid yolk sac tumor and ovarian hepatocellular carcinoma were also negative for alpha-fetoprotein. In conclusion, hepatocyte paraffin 1 is positive in primary ovarian tumors with hepatoid differentiation, with the degree of hepatocyte paraffin 1 positivity correlating with the degree of hepatoid differentiation. Hepatocyte paraffin 1, however, is not useful in distinguishing metastatic hepatocellular carcinoma from primary ovarian hepatoid carcinoma or hepatoid yolk sac tumor.     

Rural Demographics Racial/Ethnic Diversification in Metropolitan and Nonmetropolitan Population Change in the United States: Implications for Health Care Provision in Rural America

The diversification of the rural population of the United States provides substantial challenges to the current and to future health care systems in rural areas. Because of a variety of historical, discriminatory, and other factors, minority populations have had lower levels of access to health care in rural as well as urban areas and higher rates of both mortality and morbidity than nonminority populations. Although minority health issues have often been seen as primarily urban issues, this article demonstrates that minority population growth has become a major component of total population growth in rural areas in the past several decades (accounting for nearly 62% of the net growth in the nonmetropolitan population of the United States in the 1980s and for nearly 42% in the 1990s), that future US population growth is likely to be largely a product of minority population growth (nearly 89% of US net population growth from 2000 to 2100 is projected to be due to minority population growth), and that the incidence of diseases and disorders in the US population will come to increasingly involve minority populations (by 2050 roughly 43% of all disease/disorder incidences would involve minority population members). The growth of younger minority populations with disproportionately impoverished socioeconomic characteristics will pose challenges for rural areas and health care systems, which also are likely to face health issues created by disproportionately older populations.     

Asbestos disease risk communication conducted by the New Jersey department of health

Since October 1985, the New Jersey Department of Health (NJDOH) has required hospitals to report all patients with a discharge diagnosis of asbestosis. As follow-up to a needs assessment survey of these patients, the NJDOH developed an educational packet including an information bulletin titled “Asbestos Disease: Medical and Legal Facts for Employees” and a pre-stamped postcard evaluation survey. The packet was sent to 1,418 patients reported by hospitals; 433 patients returned the evaluation questionnaire. The survey assessed attitudinal responses (were the materials helpful and easy to understand?) and behavioral responses (did the respondent plan on discussing the materials with a doctor or lawyer?) to the information in the packet. Of the postcard respondents, 85% found the materials helpful, and approximately half indicated that they would discuss the materials with a doctor or lawyer. Of the 33% who were proxy respondents, half appeared not to have understood that the materials had relevance to them as family members. Modifications to the protocol for the asbestos disease educational packet were made based on the evaluation data. Limitations of the evaluation survey and the value of process evaluations in risk communication projects are discussed. © 1993 Wiley-Liss, Inc.     

National Alliance for Oral Health Consensus Conference on Medically Necessary Oral Health Care: Legal issues

This paper examines medical malpractice law as it applies to medically necessary oral health care. The basic legal concepts and reported cases involving medically necessary oral health care are reviewed. It is concluded that dental professionals and consumer advocates must advance their educational and legislative advocacy efforts so that health professional colleagues and the public will become aware of the importance of these services and insurers will routinely include coverage of medically necessary oral health care in their medical and dental policies. While failure to provide medically necessary oral health care can be violative of patient rights and legally actionable, medical malpractice litigation should always be the behavior modifier of last resort.     

The effects of X monosomy on brain development: Monozygotic twins discorcant for Turner's syndrome

Monosomy for the X chromosome is the most frequent cause of Turner's syndrome, a common clinical syndrome associated with particular physical and neurobehavioral features. The results from comprehensive assessment of prepubertal monozygotic female twins discordant for X monosomy are presented. Zygosity was established with DNA Fingerprinting and no evidence of chromosomal mosaicism was seen in either child. Physical features in the affected twin were relatively mild with respect to the full spectrum of physical malformations and disabilities associated with Turner's syndrome. The neurobehavioral phenotypes of the twins were compared. Although both sisters scored in the superior range of intelligence, the affected twin's Performance IQ was 18 points less than her sister, whereas Verbal IQ showed only a 3-point difference between the sisters. Other relative differences were noted within the executive, visuospatial, and visuomotor domains of function. Behavioral evaluation indicated greater problems with attention, hyperactivity, and anxiety in the affected twin. Quantitative analysis of brain anatomy revealed evidence of both general and regional effects of X monosomy on neurodevelopment. Cerebrospinal fluid volume was increased by 25% in the affected twin compared with her sister with a corresponding decrease in gray matter volume. The right frontal, right parietal–occipital, and left parietal-perisylvian regions showed the greatest discrepancy between the sisters with respect to increased cerebrospinal fluid and decreased gray matter volumes in the twin with X monosomy. Differences in the posterior fossa were also noted with a 50% relative increase in the volumes of the fourth ventricle and cisterna magna and a 10 to 15% relative reduction in size of the cerebellar vermis, pons, and medulla in the affected twin. The association between the neurobehavioral and neuroanatomical findings in the affected twin is discussed. The unique nature of the naturally occurring genetic phenomenon seen in this twin pair provides an opportunity to more fully elucidate the neurobehavioral phenotype associated with X monosomy and Turner's syndrome.