PubMed Health⌕ Search

Biomedical subjects

D J Lanska

Publications and source records attributed to D J Lanska.

At least 73 records · Page 4Linked to original sources
PubMed1996

Interobserver variability in the classification of neonatal seizures based on medical record data.

This population-based, retrospective cohort study of neonatal seizures included all 16,428 neonates born to residents of Fayette County, Kentucky, from 1985 to 1989. Eighty potential cases were ascertained by computer search of hospital-based medical record systems, birth certificate data files, and multiple-cause-of-death mortality data files. Medical records for potential cases were abstracted, and relevant portions were reviewed independently by three neurologists using prospectively determined criteria. Both unweighted and weighted kappa statistics were used to measure agreement between each pair of observers in the classification of potential cases as seizures, possible seizures, or not seizures, adjusting for the proportion of agreement expected by chance. Agreement in the classification of potential cases was excellent (kappa = 0.72-0.79, average = 0.76; weighted kappa = 0.85-0.88, average = 0.87). The kappa extension statistic of Kraemer was used to assess agreement in the classification of seizure types by a simplification of the classification scheme of Volpe. This documented excellent agreement between raters in the classification of seizure types (kappa e = 0.72). Experienced raters can reliably classify potential cases of neonatal seizures using seizure descriptions transcribed from medical records.

Cohort Studies↗
PubMed1996

Neonatal seizures in the United States: results of the National Hospital Discharge Survey, 1980-1991.

We present nationally representative estimates of neonatal seizure risk by gender, race and geographic region of the United States. National Hospital Discharge Survey data were analyzed for the period 1980-1991. Birth-weight-adjusted risks of neonatal seizures were calculated by the direct method for each gender or race group and for each census region by 4-year intervals. The overall risk of neonatal seizures was 2.84 per 1,000 live births. Risk estimates were consistently higher in low-birth-weight infants (relative risk 3.9). Unadjusted risks were similar across race and gender groups; birth weight adjustment had very little effect. No clear temporal trend was apparent over the 12-year study period. National Hospital Discharge Survey data provide reasonable, although conservative, estimates of neonatal seizure risks nationwide. Underascertainment of neonatal seizures, particularly among sick low-birth-weight infants, is likely due to data collection limitations of the National Hospital Discharge Survey.

Birth Weight↗
PubMed1996

Results of a computerized screening of stroke patients for unjustified hospital stay.

BACKGROUND AND PURPOSE: Effective methods to monitor length of stay can help reduce unnecessary hospital stay without adversely affecting the quality of care. In this study a clinical algorithm for assessing unjustified hospital stay in stroke patients was computerized and tested. METHODS: An algorithm was developed by the authors to estimate the number of medically justified and unjustified hospital days for patients admitted with a primary diagnosis of ischemic stroke. Data for the algorithm were obtained from 177 stroke patients from an acute-care teaching hospital. The performance of the algorithm was evaluated on a subset of 46 patients by comparing the number of medically unjustified hospital days determined by the algorithm with the consensus determination of two neurologists. RESULTS: The algorithm classified 68% of the 177 patients as having some unjustified hospital days and 41% of all hospital days as unjustified. With the neurologists as the gold standard, the sensitivity of the algorithm was .89 and the specificity was .91. The correlation between the number of unjustified days determined by the algorithm and the neurologists was .76. CONCLUSIONS: There is considerable unjustified length of stay for stroke patients. Physicians can develop simple clinical algorithms for detecting unjustified hospital stay in stroke patients that provide a reasonable approximation of complex clinical judgment.

Algorithms↗
PubMed1996

Comparison of additive and multiplicative models of regional variation in the decline of stroke mortality in the United States.

BACKGROUND AND PURPOSE: Although previous studies have shown that geographic variation in the decline of stroke mortality rates may be an important contributor to the changing geographic distribution of stroke mortality in the United States, some concern has been raised that this phenomenon may be model dependent. This study examines the geographic variation in the decline of stroke mortality rates in the United States with the use of both additive and multiplicative models. METHODS: National Center for Health Statistics and Bureau of the Census data were used to assess regional-level temporal trends of underlying-cause stroke mortality rates in the United States for 1979 through 1989. Both additive and multiplicative models were fit to the data. RESULTS: Underlying-cause stroke mortality rates have declined fairly steadily in all regions of the United States and for all race-sex groups, although there was significant regional variation in the rate of decline during the period 1979 through 1989. The South, which initially had the highest rates, had the most rapid decline for all race-sex groups when either additive or multiplicative models were used. CONCLUSIONS: From 1979 through 1989 there was significant geographic variation in the rate of decline of stroke mortality rates, with the most rapid rates of decline in the South. As a result, there has been a decrease in interregional variation in stroke mortality rates.

Age Factors↗
PubMed1996

Stages in the recognition of epidemic pellagra in the United States: 1865-1960.

Recognition of the U.S. pellagra "epidemic" in the early part of this century occurred in stages. The recognition process distorted impressions of magnitude, rate of spread, and virulence. Unrecognized cases: Endemic pellagra developed from dietary deficiencies after the Civil War. Initially, cases were misdiagnosed as other more traditional disorders. Tradition and authority inhibited recognition. Recognition of severe cases: Beginning in 1907, outbreaks were reported in asylums. Existing severe cases came rapidly to medical attention, inflating the apparent rate of spread. Recognized cases had a fulminant course and a high case fatality. Expanded spectrum: Milder cases were increasingly recognized, leading to an exaggerated rate of increase in number of cases and a decrease in case fatality and apparent virulence. Greater sensitivity resulted largely from a shift in diagnostic thresholds, with loss of specificity and increase in false positive diagnoses. Standardization of diagnosis: Although no suitable diagnostic marker test was developed, diagnosis was ultimately standardized by development of a workable case definition and by assessment of response to an effective therapy (nicotinic acid) applied to presumptive cases.

Disease Outbreaks↗
PubMed1995

A population-based study of neonatal seizures in Fayette County, Kentucky: comparison of ascertainment using different health data systems.

Based on a population-based, retrospective cohort study of neonatal seizures in Fayette County, Kentucky, from 1985 to 1989, estimates of neonatal seizure risk were calculated from computerized databases including hospital medical records, birth certificates, and death certificates. Computerized tabulations of hospital discharge diagnoses identified 97% of cases with a positive predictive value of 75%. Birth certificates had poor sensitivity for neonatal seizures overall (37%), but identified 67% of infants who seized on the first day of life. However, careless completion of the birth certificate produced a high number of false positives. Death certificates identified no infants with neonatal seizures.

Birth Certificates↗
PubMed1995

Geographic variation in reporting of stroke deaths to underlying or contributing causes in the United States.

BACKGROUND AND PURPOSE: This study examines the geographic variation in the reporting of deaths with stroke as the underlying or contributing cause in the United States. METHODS: Data from the National Center for Health Statistics and Bureau of the Census were used to map the geographic distribution of race- and race/sex-specific, underlying-, contributing-, and multiple-cause age-adjusted stroke mortality rates in the United States by state for 1979 through 1981. RESULTS: Underlying-, contributing-, and multiple-cause age-adjusted stroke mortality rates were significantly clustered for both whites and blacks. However, the spatial distributions of underlying- and contributing-cause rates differed; there was no association between underlying- and contributing-cause rates for either racial group or for the various race/sex groups. There was no association between nonstroke mortality and stroke mortality rates. There was also very little spatial variation and no spatial clustering of the median number of contributing causes reported. CONCLUSIONS: The overall large-scale spatial distribution of resident underlying-cause stroke mortality rates cannot be explained by geographic variation in the selection of the underlying cause of death from among all causes reported on the death certificate, by different area-dependent tendencies for mortality generally, or by different tendencies to consider stroke as the cause of death when death occurs. Geographic variation in contributing-cause rates is not explained by variation in tendency to report contributing causes of death.

Age Factors↗
PubMed1995

Effects of interstate migration on the geographic distribution of stroke mortality in the United States.

BACKGROUND AND PURPOSE: This study examines the effects of lifetime net interstate migration on the geographic distribution of stroke mortality in the United States. METHODS: National Center for Health Statistics and Bureau of the Census data were used to map the geographic distribution of age-adjusted, race-, and race/sex-specific stroke mortality rates by interstate migration status for natives, outmigrants, nonmigrants, inmigrants, and residents in the United States for 1979 to 1981. RESULTS: High age-adjusted stroke mortality rates were significantly clustered in the southeastern United States for both whites and blacks; in addition, for whites, low-rate states were concentrated in some Mountain and northeastern states. Migrant status did not change this large-scale pattern, but individual states showed significant migration effects, which varied in magnitude and direction. Among whites, states that benefited from migration, with markedly lower stroke mortality rates among residents than natives, included Arizona, Colorado, District of Columbia, and Florida, whereas states that suffered from migration included California, Idaho, Montana, North Dakota, Nevada, and Oklahoma. Among blacks, only Colorado showed an apparent large benefit from migration, whereas 21 states suffered from migration. CONCLUSIONS: Although the overall large-scale spatial distribution of resident stroke mortality rates cannot be explained by migration effects, some individual states had rates that were strongly influenced by migration. Patterns of mortality among migrant groups in Sun Belt retirement destination states probably result from differential selection effects for retirement migration in older adults. Patterns of mortality for black migrants to the North are probably influenced by "carryover" effects from their origin states.

Adult↗
PubMed1995

Geographic variation in the decline of stroke mortality in the United States.

BACKGROUND AND PURPOSE: This study examines the geographic variation in the decline of stroke mortality rates in the United States. METHODS: National Center for Health Statistics and Bureau of the Census data were used to assess regional and state level temporal trends of stroke mortality in the United States for 1970 to 1989. RESULTS: Underlying- and multiple-cause stroke mortality rates have declined fairly steadily in all regions of the United States and for all race/sex groups, although the rates of decline were greater during 1970 to 1978 than during 1979 to 1989. The declines in underlying-cause rates could not be attributed to a shift toward reporting stroke as a contributing rather than underlying cause of death, since both underlying- and multiple-cause rates declined similarly. There was significant regional variation in the rate of decline, particularly during 1979 to 1989. The South initially had the highest rates, but it experienced the most rapid decline, so that by 1989 the South no longer had the highest rates. States with the most rapid rates of decline were significantly clustered in the South and particularly the Southeast. Most of the decline in overall stroke mortality was due to declines in ischemic stroke mortality. CONCLUSIONS: During 1970 to 1989 there was significant geographic variation in the rate of decline of stroke mortality rates, with the most rapid rates of decline concentrated in the high-rate areas of the South and particularly the Southeast. As a result, there has been a decrease in interregional and interstate variation in stroke mortality rates, which is apparently not due to an artifact of changing reporting patterns.

Age Factors↗
PubMed1995

A population-based study of neonatal seizures in Fayette County, Kentucky.

This population-based, retrospective cohort study of neonatal seizures included all neonates born to residents of Fayette County, Kentucky, from 1985 to 1989. We ascertained potential cases by computer search of hospital-based medical record systems, Kentucky Center for Health Statistics birth certificate data files, and National Center for Health Statistics multiple-cause-of-death mortality data files. Medical records for potential cases were abstracted, and relevant portions were reviewed independently by three neurologists using prospectively determined case-selection criteria. Seizures occurred in 58 of 16,428 neonates (3.5/1,000 live births). An additional 15 neonates had possible seizures, for a combined risk of 4.4/1,000 live births. Neonatal seizure risk varied inversely with birth weight: 57.5/1,000 live births among very low birth weight infants (< 1,500 grams) compared with 4.4/1,000 for infants with moderately low birth weight (1,500 to 2,499 grams), 2.8/1,000 for those with normal birth weight (2,500 to 3,999 grams), and 2.0/1,000 for those with high birth weight (4,000 or more grams). Risk varied among the four hospitals in the county with obstetric units, the university hospital having the highest risk. Risk did not differ by race or gender. A Cox proportional hazards model confirmed the results of the simpler univariate analyses. Differences in birth weight of the subpopulations served by each hospital accounted for much but not all the differences in hospital-specific risk.

Cohort Studies↗
PubMed1995

Familial progressive subcortical gliosis: presence of prions and linkage to chromosome 17.

Progressive subcortical gliosis (PSG) is a sporadic and familial dementing disease characterized pathologically by astrogliosis at the cortex-white matter junction, a feature present in some prion diseases. With immunocytochemical and Western blot analyses, we investigated the presence of deposits of the prion protein (PrP) and of the protease-resistant PrP isoform, the hallmarks of prion diseases, in six affected members of two large kindreds with PSG. The coding region of the PrP gene was sequenced and chromosomal linkage determined. We demonstrated "diffuse" PrP plaques in the cerebral cortex of two subjects from one kindred and protease-resistant PrP fragments in four of the five subjects examined. We found no mutation in the coding region of the PrP gene. Moreover, the disease was linked to chromosome 17 and not to chromosome 20, where the PrP gene resides. The familial form of PSG is the first human genetic disease characterized by the presence of protease-resistant PrP that lacks a mutation in the coding region of the PrP gene. The linkage to chromosome 17 suggests that other genes are involved in the PrP metabolism. Whether the protease-resistant PrP plays a primary or secondary role in the pathogenesis of this form of PSG remains to be determined.

Adult↗
PubMed1994

Length of hospital stay for cerebrovascular disease in the United States: Professional Activity Study, 1963-1991.

OBJECTIVE: To assess the temporal and spatial variation in length of hospital stay for cerebrovascular disease in the United States over three decades. DESIGN: Age-, region-, and stroke type-specific length-of-hospital-stay data for nearly 4 million patients admitted with cerebrovascular disease were obtained for the Professional Activity Study of the Commission on Professional and Hospital Activities for the period 1963-1991. MAIN OUTCOME MEASURE: Weighted averages and standard errors of length of stay were calculated for aggregate diagnosis groups within the category of cerebrovascular disease. Averages were age-adjusted by the direct method. RESULTS: Average length of hospital stay declined from a peak of 18 days in 1967 to 8 days in 1991. The decline accelerated sharply from 1982 to 1986 coincident with implementation of the Medicare prospective payment system. Similar declines were observed within each age group, each cerebrovascular disease diagnosis group, and each census region. There were marked and persistent differences in average length of stay between regions, with longer stays in the Northeast and shorter stays in the West. The large interregional variation was not explained by differences in age or cerebrovascular disease diagnoses. CONCLUSIONS: Implementation of the Medicare prospective payment system produced a marked decline in length of hospital stay for cerebrovascular disease, which was superimposed on a preexisting, but slower, decline. Much of the marked persistent interregional variation probably results from persistent widespread variation in patient management.

Age Factors↗