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D K Li

Publications and source records attributed to D K Li.

At least 55 records · Page 3Linked to original sources
PubMed1995

Score for neonatal acute physiology: validation in three Kaiser Permanente neonatal intensive care units.

BACKGROUND: Measurement of the severity of illness is a research area of growing importance in neonatal intensive care. Most severity of illness scales have been developed in tertiary care settings. Their applicability in community neonatal intensive care units has not been tested. OBJECTIVES: Our goal was to assess the operational characteristics of the score for neonatal acute physiology (SNAP): the relationship to birth weight, the length of total hospital stay, and in-hospital mortality. METHODS: We assigned SNAP scores prospectively to all inborn admissions at three community neonatal intensive care units during an 11-month period. Data on other neonatal predictors (eg, birth weight and the presence of congenital heart disease) were also collected. We measured in-hospital mortality, the experience of interhospital transport to a higher level of care, and total hospital stay. RESULTS: We found that the SNAP's relationship to birth weight was similar to previous reports. The SNAP's perinatal extension is a reliable predictor of newborn in-hospital mortality, with an area under the receiver operator characteristic curve of 0.95. The SNAP is also a good predictor of total hospital length of stay, whether by itself (by which it can explain 31% of the total stay) or in combination with other variables. Its predictive ability is better among infants of low birth weight (<2500 g) than among those of normal birth weight (> or = 2500 g). The SNAP's predictive power was most limited among infants admitted to rule out sepsis. The predictive ability of a model containing birth weight, the SNAP, and transport status was not improved by the inclusion of two major diagnostic categories, the presence of congenital heart disease or complex illness. CONCLUSION: Although it has definite limitations among infants who weight 2500 g or more, the SNAP is a potent tool for outcomes research. Modification of some of its parameters could result in a multifunctional scale suitable for use with all birth weights.

Birth Weight↗
PubMed1993

The effect of parity on the relation between maternal history of spontaneous pregnancy loss and the risk of sudden infant death syndrome in offspring.

We conducted a population-based case-control study, using the 1984-1989 linked Washington State birth and death certificate data, to determine whether maternal prior spontaneous pregnancy loss was associated with the risk of sudden infant death syndrome (SIDS). We identified 872 autopsied SIDS cases and 3,704 controls matched to cases on year of birth. To reduce the confounding from unmeasured socioeconomic and behavioral factors, we analyzed the data separately for infants with and without father's race provided on the birth certificate. Among infants whose father's race was known, those of multiparous women with a prior spontaneous pregnancy loss before 20 weeks gestational age were at reduced risk of SIDS, after adjustment for maternal age, prenatal smoking,a nd gravidity. An increased number of prior pregnancy losses was associated with a further reduction in the risk of SIDS: one prior pregnancy loss was associated with a 25% decrease [odds ratio (OR) = 0.75; 95% confidence interval (CI) = 0.52-1.08], and two or more prior pregnancy losses was associated with a 47% decrease (OR = 0.53; 95% CI = 0.30-0.94). There was no such association, however, among infants of women with no prior livebirth. Similar associations were observed between prior spontaneous pregnancy loss during the entire gestational period and the risk of SIDS in offspring. To explain the different associations between maternal prior pregnancy loss and the risk of SIDS observed among infants of women with and without a prior livebirth, we hypothesize an upward bias resulting from the presence of a larger proportion of infants of human leukocyte antigen-compatible couples among first liveborn infants.

Abortion, Spontaneous↗
PubMed1993

Maternal prior pregnancy loss and the sex ratio among infants with sudden infant death syndrome.

It has been reported that the offspring of human leukocyte antigen (HLA)-compatible parents may have a high male/female sex ratio. To study the hypothesis that parental HLA compatibility is related to sudden infant death syndrome (SIDS), I conducted a population-based case-control study using 1982-1990 linked Washington State birth and death certificate data to compare the sex ratio of SIDS cases and controls. SIDS cases were identified by the International Classification of Diseases, 9th revision, CM code 798.0, on the death certificate, and four controls born in the same year as the case were randomly selected for each case. I categorized the infants according to maternal parity and history of pregnancy loss. There was a high risk of SIDS in males relative to females among first liveborn infants whose mothers had had two or more prior pregnancy losses (odds ratio = 7.6, 95% confidence interval = 1.5-39). I had hypothesized a priori that this group would have the largest proportion of infants of HLA-compatible parents. No similar association was observed among infants with a prior liveborn sibling. In addition to the findings from two previous studies, this finding provides further evidence that parental HLA compatibility may be related to the risk of SIDS in offspring.

Abortion, Spontaneous↗
PubMed1993

Concordance of parental race/ethnicity in relation to the risk of sudden infant death syndrome (SIDS).

It has been reported that parental human leukocyte antigen (HLA) compatibility is associated with certain adverse reproductive outcomes such as multiple spontaneous fetal losses and malformations, particularly among women without a prior livebirth. In order to study the relation between parental HLA compatibility and the risk of SIDS, a population-based case-control study was conducted using 1982-1990 Washington State linked birth and death certificate data. Concordance of parental race/ethnicity combined with prior maternal fetal loss was used as surrogate measures of parental HLA compatibility. The relation was evaluated separately among infants with and without a prior live-born sibling. Among first liveborn infants, those of racially discordant parents were at reduced risk of SIDS compared with those of racially concordant parents (relative risk [RR] = 0.57, 95% confidence interval = 0.34-0.96). Infants of white-minority parents were all at lower risk of SIDS than infants of white-white parents. Infants of racially concordant parents with two or more prior fetal losses were at increased risk of SIDS (RR = 2.44, 1.07-5.56), relative to infants of racially discordant parents. No such associations were observed among infants with prior live-born siblings. In fact, in this latter population, infants of racially concordant parents tended to have a lower risk of SIDS than those of discordant parents. This study suggests that a portion of SIDS cases, particularly among first live-born infants, may be due to parental HLA sharing. However, final determination of the existence of this relationship requires actual HLA typing of parents of both cases and controls.

Adult↗
PubMed1993

The use of magnetic resonance imaging in monitoring interferon therapy of multiple sclerosis.

Magnetic resonance imaging (MRI) was used to evaluate the efficacy of systemic lymphoblastoid interferon therapy in chronic progressive multiple sclerosis. The clinical outcome of this trial has been reported previously. Thirty-six patients with chronic progressive multiple sclerosis were treated with interferon daily for 6 months and 27 received placebo. Patients had MRI at the outset of the study and after 6 and 24 months. Lesion activity and changes in lesion load were determined. As the study progressed, both the interferon- and the placebo-treated group developed more active lesions. There was no difference in lesion activity between the two groups. Comparison of lesion load, however, showed a trend toward improvement after 6 months for the interferon-treated group. This difference between the two groups had disappeared by the end of the study. We conclude that lymphoblastoid interferon was not effective in decreasing active MRI-detected lesions or in decreasing MRI lesion load in patients with chronic progressive multiple sclerosis.

Adult↗
PubMed1993

Interferon beta-1b is effective in relapsing-remitting multiple sclerosis. II. MRI analysis results of a multicenter, randomized, double-blind, placebo-controlled trial. UBC MS/MRI Study Group and the IFNB Multiple Sclerosis Study Group.

We performed yearly MRI analyses on 327 of the total 372 patients in a multicenter, randomized, double-blind, placebo-controlled trial of interferon beta-1b (IFNB). Clinical results are presented in the preceding companion paper. Baseline MRI characteristics were the same in all treatment groups. Fifty-two patients at one center formed a cohort for frequent MRIs (one every 6 weeks) for analysis of disease activity. The MRI results support the clinical results in showing a significant reduction in disease activity as measured by numbers of active scans (median 80% reduction, p = 0.0082) and appearance of new lesions. In addition, there was an equally significant reduction in MRI-detected burden of disease in the treatment as compared with placebo groups (mean group difference of 23%, p = 0.001). These results demonstrate that IFNB has made a significant impact on the natural history of MS in these patients.

Adult↗
PubMed1992

Structural brain imaging abnormalities associated with schizophrenia and partial trisomy of chromosome 5.

Chromosomal abnormalities occurring in association with mental illness provide a unique opportunity to study the interaction of genetic abnormalities and the brain in mental illness. Four individuals from a family in which schizophrenia was found to cosegregate with a partial trisomy of chromosome 5 were studied with computed tomography and magnetic resonance imaging. Temporal lobe atrophy was found in the two trisomic males and in the asymptomatic balanced translocation female. In addition, a large cavum septum pellucidum and a cavum vergae were found in the older trisomic individual. Scans from the normal male were free of abnormalities. These results suggest that molecular studies of the translocation breakpoints in this chromosomal abnormality may be of interest, and encourage further studies of brain structure in other chromosomal abnormalities associated with psychosis.

Adult↗
PubMed1991

Maternal smoking, low birth weight, and ethnicity in relation to sudden infant death syndrome.

To determine independent effects of maternal smoking and infant low birth weight (less than 2,500 g) on risk of sudden infant death syndrome (SIDS) among different ethnic groups, the authors conducted a population-based case-control study based on the 1984-1989 Washington State birth record data. Two control groups were selected for 916 SIDS cases. The first one comprised 3,704 randomly selected controls, matched to cases by birth year, to describe the characteristics of the study population. In the second control group (n = 6,186), minorities were oversampled, by matching to cases on maternal race/ethnicity and birth year, to increase the power of analysis within each ethnic group. All subjects were classified into five groups on the basis of maternal race/ethnicity: white, black, American Indian, Asian, and Hispanic. After controlling for confounders, the authors found that maternal smoking was independently associated with SIDS among white (odds ratio (OR) = 2.2, 95% confidence interval (CI) 1.8-2.6), blacks (OR = 3.1, 95% CI 1.7-5.9), Asians (OR = 2.7, 95% CI 1.1-6.6, and Hispanics (OR = 5.5, 95% CI 1.4-22.0), but had little relation among American Indians (OR = 1.4, 95% Cl 0.9-2.4). Infant low birth weight was independently related to SIDS among whites (OR = 2.5, 95% Cl 1.8-3.4) and American Indians (OR = 5.5, 95% Cl 2.8-11.2) and to a lesser extent among blacks (OR = 1.9, 95% Cl 0.8-4.1), but not among Asians (OR = 1.1, 95% Cl 0.2-5.2) or Hispanics (OR = 1.2, 95% Cl 0.1-11.5). The misclassification that may occur because of the application of the same definition of low birth weight to all ethnic groups may be the main reason for the weaker association between infant low birth weight and SIDS among blacks and the absence of an association among Asians and Hispanics. Defining low birth weight as below population mean minus 1.96 standard deviations may provide better insight into the relation between low birth weight and SIDS. Understanding the reasons for the lack of a strong association between maternal smoking during pregnancy and SIDS among American Indians may enhance our knowledge of the etiology and pathogenesis of SIDS.

Adult↗
PubMed1991

Magnetic resonance imaging of the head in the diagnosis of multiple sclerosis: a prospective 2-year follow-up with comparison of clinical evaluation, evoked potentials, oligoclonal banding, and CT.

We previously compared the diagnostic capabilities of MRI of the head with CT, evoked potentials, and CSF oligoclonal banding (OB) analysis in a prospective evaluation of 200 patients with suspected multiple sclerosis (MS). To examine the ability of MRI and other paraclinical tests to predict the diagnosis of clinically definite MS (CDMS), we did a systematic clinical follow-up of 200 patients who were previously reported. In that study, 85 of 200 could be diagnosed as having laboratory-supported definite MS (LSDMS). In follow-up, we excluded one patient diagnosed as LSDMS who in retrospect was considered to have had CDMS at entry and 15 patients who were eventually diagnosed as having other diseases. After a mean follow-up of 2.1 years, 55 of the remaining 184 patients (30%) had developed CDMS. Thirty-eight of 84 patients with an original diagnosis of LSDMS (45%) and 17 of the remaining 100 patients with suspected MS (17%) had become CDMS. Forty-six of the 55 patients who developed CDMS in follow-up (84%) had an initial MRI that was strongly suggestive of MS. Fifty-two of those 55 CDMS patients (95%) had at least one MS-like abnormality on MRI when originally studied. In contrast, 38 of 55 (69%) had CSF OB, 38 of 55 (69%) had an abnormal VEP, 35 of 55 (64%) had an abnormal SEP, and 21 of 55 (38%) had an abnormal CT when first studied. MRI was the most sensitive single paraclinical test for predicting CDMS. CDMS developed during follow-up in 46 of the 94 patients (49%) whose initial MRI was strongly suggestive of MS.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Evaluation of cartilage lesions by magnetic resonance imaging at 0.15 T: comparison with anatomy and concordance with arthroscopy.

Recent evidence suggests that pharmacological treatment may alter the rate of progression of cartilage damage in osteoarthritis (OA). However, a lack of accurate and precise noninvasive assessments of cartilage structure makes it difficult to answer this question directly with prospective clinical trials, prevents early diagnosis of OA and restricts assessment of treatment to evaluation of symptoms or joint function. It is important, therefore, to develop precise, noninvasive methods both for diagnosis of early OA before damage is extensive and irreversible and for evaluation of therapeutic effectiveness. Magnetic resonance imaging (MRI) allows for noninvasive, multiplanar body imaging which depends on proton density, flow, and the T1 and T2 relaxation times. Because these variables differ markedly among joint tissues, cartilage erosions are visible with MRI and it should be possible to quantify them. Our objective was to compare MRI with arthroscopy for assessing the depth of lesions in the articular cartilage of human knees to help develop and validate MRI for use in clinical trials designed to assess the effect of therapy on cartilage structure. In the first part of our study, the effect of the MRI pulse sequence variables on the images was evaluated by varying them systematically and comparing the anatomy seen with MRI with that seen at arthroscopy or arthrotomy and with the histology. In the second part, 31 patients were assessed with MRI before arthroscopy. The MRI were graded on a 4-point ordinal scale by 2 observers who were unaware of the clinical diagnosis and compared with findings at arthroscopy which were graded using the same scale.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthroscopy↗
PubMed1990

Systemic lymphoblastoid interferon therapy in chronic progressive multiple sclerosis. I. Clinical and MRI evaluation.

A randomized, double-blind, placebo-controlled, noncrossover trial determined the efficacy of lymphoblastoid interferon (IFN) in chronic progressive multiple sclerosis (CP MS). Fifty patients received 5 X 10(6) IU IFN subcutaneously daily for 6 months while 50 received placebo. After 2 years, there were no significant differences between the 2 groups based on clinical evaluations and quantitative MRI analysis of the brain, although a trend was observed in the IFN group. Clinically, the IFN group was worse at 1 and 3 months and improved at 6 to 18 months, when compared with the placebo group. Results of MRI evaluations of the brain at 6 months support this trend. This trend likely resulted from a subpopulation of 10 IFN-treated patients, characterized by a higher women:men ratio and a lower EDSS score at entry into the trial. We cannot recommend lymphoblastoid IFN as treatment for CP MS at this time.

Adult↗
PubMed1990

Secular change in birthweight among southeast Asian immigrants to the United States.

We analyzed the Washington State births in 1980-1986 to Southeast Asian parents whose birth place was coded as being outside of the US. The mean birthweight increased from 3188 grams in 1980-81 to 3283 grams in 1986, an annual increment of about 18 grams (95% CI = 11, 25 grams). The prevalence of low birthweight (less than 2500 grams) decreased from 7.2 percent in 1980-81 to 5.4 percent in 1986, an annual reduction of 6.4 percent (95% CI = 1.3, 11.2 percent). In an analysis of information ascertained from the birth certificate, the change of paternal occupational status (from student to employed) was associated with 27 percent of the reduction in the prevalence of low birthweight, independent of maternal age, infant sex, and prior gravidity. A similar temporal change of birthweight during the same period of time was not observed among infants of US-born Asian mothers. Among the women who had two consecutive births from 1984 to 1986, the improvement of birthweight for the second birth compared to the first birth was much greater in infants born to the Southeast Asian mothers than that to White mothers. Our study suggests that living in the United States after immigration from their native countries has had a positive impact on the birthweight of infants born to Southeast Asian immigrants.

Adult↗