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S M Lai

Publications and source records attributed to S M Lai.

At least 37 records · Page 2Linked to original sources
PubMed1999

Evaluation of the American Heart Association Stroke Outcome Classification.

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the concurrent validity of the American Heart Association Stroke Outcome Classification (AHA.SOC) and compare performance of its function classification with that of the Modified Rankin Scale. METHODS: The individuals in this study included the last 105 consecutive subjects who were part of a cohort of 459 stroke patients in the Kansas City Stroke Study. The patients were evaluated with a variety of standardized assessments at enrollment (within 14 days of stroke onset) and followed at 1, 3, and 6 months after stroke. Specifically, we examined validity of AHA.SOC by comparing its 3 domains (ie, Domain, Severe, and Function) with stroke severity. We correlated AHA.SOC-Function with scores of the Barthel Index, Lawton Instrumental Activities of Daily Living (IADL) Scale, and Medical Outcome Study 36-Item Short-Form Health Survey (SF-36) measures of physical function and mental health. Finally, we compared the discriminant ability of AHA.SOC-Function and the Modified Rankin Scale in assessing disability and handicap. These data were analyzed with the use of Spearman rank correlations and Kruskal-Wallis tests. RESULTS: All 3 domains of the AHA.SOC were significantly associated with stroke severity and scores of Barthel Index, Lawton IADL, and SF-36 physical function (all P<0.001). Both AHA.SOC-Function and the Modified Rankin Scale discriminated well the disabilities and handicap measured by Barthel Index, Lawton IADL, and SF-36 physical function (all P<0.001). CONCLUSIONS: The AHA.SOC was able to capture impairments, disabilities, and handicap after stroke. The AHA. SOC-Function performed equally as well as the Modified Rankin Scale in assessing disabilities related to basic activities of daily living but differentiated slightly better than the Modified Rankin Scale in assessing disabilities/handicap related to instrumental activities of daily living. Neither the AHA.SOC-Function nor the Modified Rankin Scale captured differences in mental health after stroke.

Aged↗
PubMed1999

Development of a comprehensive assessment toolbox for stroke.

Comprehensive databases for the assessment of individuals with stroke are essential for clinical management and evaluation of outcomes for quality management and research. The purpose of this article is to describe a comprehensive data system or "toolbox" developed by clinicians and researchers at the Center on Aging at the University of Kansas Medical Center. The choice of assessments for the toolbox resulted from the Agency for Health Care Policy and Research Post-Stroke Rehabilitation Guidelines, results of the Kansas City Stroke Study, and the authors' work to develop a new stroke measure-the Stroke Impact Scale.

Aged↗
PubMed1998

Disposition after acute stroke: who is not sent home from hospital?

BACKGROUND: Known demographic and clinical characteristics of stroke survivors that affect selection of the facility to which they are discharged after hospitalization for an acute stroke are, for the most part, not population based and therefore may be unrepresentative. We present an analysis of such characteristics using the Lehigh Valley stroke cohort which is population based. METHOD: We enrolled patients within 1 month of onset of their initial acute stroke who were hospitalized between 1987 and 1989 at one of the eight hospitals in the Lehigh Valley, and 662 patients were discharged alive. The facility to which they were discharged was known for 660. Data on age, sex, presence of five selected comorbidities (hypertension, myocardial infarction, cardiac arrhythmia, diabetes mellitus and transient ischemic attacks), length of hospitalization and neurologic deficits from the stroke were systematically collected on standardized forms. Polytomous logistic regression was used to determine the factors associated with not being discharged home. Relative risk (RR) associated with discharge to a nursing or rehabilitation facility for each independent predictor was calculated using as the referent, those who went home. RESULTS: Older age was a statistically significant predictor of not being sent home (RR = 1.2 for nursing home placement), but gender and living with a spouse were not. Having a selected comorbidity did not increase the RR of not being sent home regardless of the type, nor did risk of not being sent home increase with more than one illness. Considering neurologic deficits from the stroke, patients with lower extremity weakness had a 2.6- and 3.5-fold risk of being sent to a nursing or a rehabilitation facility, respectively, compared to those without such weakness while for those with upper extremity weakness, the RR was 1.5 and 4.9, respectively. Language deficit imposed a RR of 3.1 and 2.3 of going to a nursing or rehabilitation facility, respectively. Right facial weakness also emerged as a significant risk factor for not being discharged home, perhaps because of its association with language deficit. The longer a patient was hospitalized after a stroke, the less likely it was that such a patient would go home (RR = 1.1/hospitalization day). CONCLUSION: Using population-based data on stroke survivors, our study showed the characteristics of patients who are less likely to be discharged home and, instead, are discharged to a nursing or a rehabilitation facility. Data like ours which were population based may be useful in discharge planning for stroke patients by policy makers and health care providers.

Acute Disease↗
PubMed1998

Prediction of functional outcome after stroke: comparison of the Orpington Prognostic Scale and the NIH Stroke Scale.

BACKGROUND AND PURPOSE: This study compared the ability of 2 stroke impairment scales, Orpington Prognostic Scale and National Institutes of Health (NIH) Stroke Scale, to predict disability as measured by the Barthel activities of daily living (ADL) Index and higher level of self-reported physical functioning as measured by the SF-36 physical functioning index (PFI) at 1, 3, and 6 months after stroke. METHODS: The participants in this ongoing study are 184 individuals who sustained an eligible stroke and were recruited for the Kansas City Stroke Study. All patients were prospectively evaluated using standardized assessments at enrollment (within 14 days of stroke onset) and followed at 1, 3, and 6 months after stroke. Coefficient of determination (R2) was used to assess the ability of the 2 stroke scales to prognosticate outcomes. RESULTS: Means and SDs of the Orpington Prognostic Scale and NIH Stroke Scale measured at baseline were 3.6+/-1.31 and 5.5+/-4.58, respectively. The Spearman's rank correlation between the 2 baseline measures was 0.83 (P=0.0001). The Orpington Prognostic Scale and the NIH Stroke Scale explained well the variance in Barthel ADL Index (P<0.001). However, the Orpington Prognostic Scale explained more variance than did the NIH Stroke Scale. Similarly, the Orpington Prognostic Score explained more variance in higher level of physical function than did the NIH Stroke Scale. The amount of variance in Barthel ADL Index and SF-36 PFI, which were explained by both stroke severity measures, decreased over time. CONCLUSIONS: Our results demonstrate that in a sample of mostly mild and moderate strokes, the Orpington Prognostic Scale compared with the NIH Stroke Scale is simpler to use and is a slightly better predictor of ADL and higher levels of physical function.

Activities of Daily Living↗
PubMed1997

Synaptic relationships between corticocuneate terminals and glycine-immunoreactive neurons in the rat cuneate nucleus.

The present study describes the ultrastructural synaptic relationships between corticocuneate terminals (CCTs) and glycine-immunoreactive (glycine-IR) neurons in the cuneate nucleus of rats using anterograde tract-tracing of wheatgerm agglutinin conjugated with horseradish peroxidase (WGA-HRP) and anti-glycine immunoperoxidase labeling methods. The HRP-labeled CCTs made axodendritic synapses preferentially in the ventral part of the cuneate nucleus near the obex. In a total of 182 CCTs surveyed, 14 of them made direct synaptic contacts with immunoperoxidase-labeled glycine-IR dendrites. The present results suggest that cortical modulation on the sensory transmission of cuneate nucleus may be mediated through glycine-IR neurons.

Animals↗
PubMed1997

Cancer cluster investigation in a school district.

Because of concern about a possible cancer cluster among employees of an elementary school, an industrial hygiene survey and health investigation were completed. An indoor-air quality survey was conducted by a certified industrial hygienist (CIH). A separate health survey concerning cancer occurrence was conducted by the authors among current (1995) and former (back to 1990) employees. Cancer data from the state health department registry were used to supplement self-reports. The number of observed cancers were compared to those expected based on statewide and county data. A marginally significant increased risk was found for breast cancer among female employees who had worked for the school. No other excess in cancers was found. This excess of breast cancer was unlikely to have been related to an occupational exposure. Based on the study supported by the school district, which prefers to remain anonymous, this paper discusses the conduct of cancer cluster investigations in schools and recommends that screening and education for breast cancer be conducted in schools.

Adult↗
PubMed1997

Stroke recurrence in diabetics. Does control of blood glucose reduce risk?

BACKGROUND AND PURPOSE: Patients with diabetes are at increased risk of stroke. Risk might be reduced if blood glucose level were controlled. METHODS: In a population-based study, we enrolled 621 patients within a month of an initial ischemic stroke and followed them regularly twice annually; 198 were diabetic. We monitored blood glucose level in 142 (72%) using glycosylated hemoglobin (HbAlc). Recurrent stroke frequency was determined by history, examination, and medical records. Cox proportional hazards models were used to examine the relationship between risk of recurrent stroke and HbAlc level. The models included interaction with time-dependent HbAlc level and history of diabetes, selected medical comorbidities, age, and sex. HbAlc level was analyzed as both a continuous and a dichotomous variable (ie, controlled versus uncontrolled); "controlled" was defined with different cut points. RESULTS: All but 17 patients (12%) whose blood glucose was monitored were well controlled (HbAlc < 8%). HbAlc level was not associated with increased risk of stroke recurrence (hazard ratio [HR], 0.87 per 1% increment in HbAlc; 95% confidence interval [CI], 0.623 to 1.219), nor was there a trend toward increased risk of recurrent stroke as the cut point defining "controlled" increased: with HbAlc at < 6%, the HR for the uncontrolled group was 0.51 (95% CI, 0.176 to 1.503); at < 7%, it was 0.43 (95% CI, 0.089 to 1.923); and at < 8%, it was also 0.43 (95% CI, 0.057 to 3.317). CONCLUSIONS: Among diabetic patients with an initial stroke, no association between HbAlc level over time and risk of stroke recurrence was found. However, most patients in this cohort were well controlled, and any adverse effect of poor control could not be adequately tested.

Aged↗
PubMed1995

Prognosis for survival after an initial stroke.

BACKGROUND AND PURPOSE: We studied prognosis for survival after an initial stroke in 662 patients who survived at least 30 days after onset while taking into account age, sex, the number of neurological deficits from the initial stroke, stroke type, and five selected medical conditions: hypertension, myocardial infarction, cardiac arrhythmia, diabetes mellitus, and history of transient ischemic attacks. METHODS: All patients were enrolled between July 1, 1987, and August 1, 1989, and were followed regularly at about 6-month intervals until death or the end of the study (mean of 24 months). RESULTS: At 6 months, 90.8% of the 30-day stroke survivors were still alive. At 1, 2, 3, and 4 years, the cumulative survival rates were 86.9%, 78.7%, 73.2%, and 72.0%, respectively. Older age and the number of neurological deficits at onset of initial stroke increased risk of death. Compared with patients of the same age, sex, number of neurological deficits, and comorbidities, increased risk of death is present among those with myocardial infarction, cardiac arrhythmia, and diabetes mellitus. Hazard ratios were 1.7 (P = .006), 1.5 (P = .023), and 1.4 (P = .059), respectively. Hypertension and transient ischemic attacks were not significantly associated with increased mortality. CONCLUSIONS: This study clarifies prognosis for survival after an initial stroke by taking into account other confounding variables that could also contribute to risk of death.

Age Factors↗
PubMed1994

Lymph node classification systems in cutaneous T-cell lymphoma. Evidence for the utility of the Working Formulation of Non-Hodgkin's Lymphomas for Clinical Usage.

BACKGROUND: This study was undertaken to compare three classification schemes used to evaluate lymph nodes (LN) obtained from patients with cutaneous T-cell lymphoma (CTCL): a modified Rappaport classification, the National Cancer Institute-Veterans Administration (NCI-VA) classification based on the relative numbers of cerebriform cells in the paracortical areas, and the Dutch classification based on the presence of cerebriform cells with large nuclei in mycosis fungoides (MF) and diffuse infiltration by cerebriform cells in Sézary syndrome. METHODS: A study set of 195 LN obtained from patients with CTCL (MF, Sézary syndrome, and nonepidermotropic T-cell lymphomas) and 14 LN from patients with benign dermatoses was reviewed independently by three groups of pathologists familiar with each classification system. RESULTS: Each classification system provided useful prognostic information. However, contrary to prior reports, no significant difference in survival was apparent in patients with uneffaced LN when classified according to the NCI-VA (LN0-2 versus LN3) or Dutch (Gr0-1 versus Gr2) ratings. In addition, all classification systems demonstrated a poor survival time associated with effaced LN. By combining results from the modified Rappaport and Dutch classifications, three prognostic groups could be identified based on cell morphology: a low-grade category with a small cell histologic subtype (median survival time, 40 months); a high-grade immunoblastic subtype (median survival time, 9 months) composed of cells with an oval nucleus containing a large, usually solitary central nucleolus; and an intermediate-grade category composed of all cases without the distinctive small cell and immunoblastic morphologies (median survival time, 26 months). CONCLUSIONS: The authors propose that clearly involved LN in CTCL can be categorized on the basis of cell morphology into prognostic groups analogous to what has been proposed for the Working Formulation for Non-Hodgkin's Lymphomas for Clinical Usage.

Cell Transformation, Neoplastic↗
PubMed1994

A multifactorial analysis of risk factors for recurrence of ischemic stroke.

BACKGROUND AND PURPOSE: Risk factors for stroke recurrence have usually been evaluated as single variables. This study is a multivariate analysis of five risk factors (hypertension, myocardial infarction, cardiac arrhythmia, diabetes mellitus, and transient ischemic attacks) for second stroke after an initial ischemic stroke. METHODS: Six hundred twenty-one patients with an acute ischemic stroke were followed prospectively first at 4 months after onset and then at approximately 6-month intervals until death, recurrence of stroke, or the end of the study. The five risk factors were measured at each visit. A Cox multifactorial regression analysis was conducted using the risk factor status at enrollment and adjusted for age and sex. RESULTS: Follow-up averaged 24 months (range, 1 to 48 months). Men comprised 52% of the cohort and were slightly older; 97% of the cohort was white, and 57% had multiple risk factors. Hypertension occurred in 59%, cardiac arrhythmia in 47% (of which 16% had atrial fibrillation), diabetes mellitus in 30%, myocardial infarction in 25%, and transient ischemic attacks in 18%. Only history of hypertension and atrial fibrillation by electrocardiogram were associated with increased risk of second stroke independently and significantly (P = .01 and P = .04, respectively). CONCLUSIONS: Among the five factors analyzed, control of hypertension and atrial fibrillation appear to offer the greatest chance of reducing risk of stroke recurrence after an ischemic stroke.

Aged↗
PubMed1994

Hypertension and risk of stroke recurrence.

BACKGROUND AND PURPOSE: Hypertension is a risk factor for initial stroke, but its relation to stroke recurrence is unclear. Therefore, we sought to analyze the effect of hypertension and its control on risk of stroke recurrence. METHODS: Within 1 month of onset, a population-based cohort of 662 patients from the Lehigh Valley with an initial stroke were enrolled. Hypertension was determined at enrollment by history. Blood pressure was also measured at enrollment and at each follow-up at 4- to 6-month intervals for up to 48 months (mean, 24 months). Stroke recurrence was verified by history, examination, and review of medical reports. Various criteria for control of blood pressure were defined. History of hypertension, measured blood pressure, and its control were analyzed in relation to stroke recurrence frequency using Kaplan-Meier and univariate, multivariate, and time-dependent Cox proportional hazards models. RESULTS: At enrollment, 59.4% of the cohort had a history of hypertension and 81 patients had a second stroke. Those with a history of hypertension had a significantly higher stroke recurrence rate than those without such a history (P = .01). Among those with measured diastolic blood pressure at enrollment > or = 95 mm Hg, 43% had a stroke recurrence by the end of the study compared with only 19% below this cutoff (P = .005). Recurrence risk was reduced in a multivariate analysis as quality of diastolic blood pressure control increased (relative risk = 8.4, 3.9, and 2.0 among those with poor, fair, and good control, respectively, compared with nonhypertensive subjects). Systolic blood pressure and its control appeared less or not significantly associated with stroke recurrence. CONCLUSIONS: History of hypertension and elevated measured diastolic pressure after the initial stroke were associated with an increased risk of second stroke. Controlling diastolic pressure substantially reduced this risk.

Age Factors↗
PubMed1993

The Lehigh Valley Recurrent Stroke Study: description of design and methods.

A community-based, prospective study was carried out in the Lehigh Valley to determine how 5 selected risk factors and their control affected the frequency of stroke recurrence and death after an initial stroke. The initial stroke was verified clinically and by computerized tomography. Between 1987 and 1989, 662 patients with an initial stroke were enrolled and followed regularly every 4-6 months for up to 7 visits. The average follow-up period was 2 years. The risk factors selected included hypertension, myocardial infarction, cardiac arrhythmia, diabetes mellitus and transient ischemic attacks. Interim death and its cause were noted. Surviving patients were interviewed and examined to determine whether a second stroke has occurred. At enrollment, 51.4% of the cohort was male. The average age of men was 69.6, while women were older, averaging 74.3 years. Stroke types were thrombosis, 14%; embolus, 23%; lacune, 9%; nonspecific infarct, 48%, and intracerebral hemorrhage, 6%. There were 138 deaths (21%) and 81 second strokes (12%) during follow-up. The frequency of risk factors at enrollment was as follows; hypertension, 59%; myocardial infarction, 25%, cardiac arrhythmia, 47% (of which 16% had atrial fibrillation); diabetes mellitus, 29%, and transient ischemic attack, 18%. Of course many patients had multiple risk factors. We analyzed whether the presence of a risk factor at enrollment and its quality of control during follow-up affected stroke recurrence frequency and the mortality rates. These results will be reported in future papers.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Lymph node histopathologic findings in cutaneous T-cell lymphoma. A prognostic classification system based on morphologic assessment.

The histopathologic features of 251 lymph nodes obtained from 200 patients with various clinical expressions of cutaneous T-cell lymphoma (mycosis fungoides and Sezary syndrome) were reviewed retrospectively. Lymphomatous involvement, defined as partial or complete effacement of lymph node architecture by malignant cells, was identified in 89 specimens (35%) and was characterized by morphologic variability from case to case. The involved specimens were classified into four major histologic subtypes according to the morphologic appearance of the malignant cells in a manner analogous to a modified Rappaport classification of diffuse non-Hodgkin's lymphomas. Although lymph node involvement was associated with a poor prognosis regardless of histologic subtype, the survival of patients with small cell (cerebriform) subtype was found to be significantly better (median survival time, 40 months) than other subtypes (median survival time, 20 months), possibly because this type of involvement sometimes preceded the development of the more aggressive mixed and large cell subtypes. Dermatopathic lymphadenopathy compared to other reactive patterns had no special prognostic importance other than its more frequent occurrence in black patients and in patients with more extensive skin involvement.

Humans↗
PubMed1992

High resolution electron microscopic investigation of atomic structural images in human atherosclerotic plaque.

Atomic structural images in the calcified matrix of human atherosclerotic plaques were characterized by high-resolution electron microscopy (HREM). The mineral elements distributed in the calcified matrix were analysed by energy dispersive X-ray microanalysis. Careful HREM observations revealed that a large number of microcrystallites and crystal particles with a broad spectrum of crystal size and perfection were embedded in the amorphous matrix of the calcified plaques. The amorphous phase in the calcified matrix was made up of a dense network of granulo-fibrillar substructures. The lattice-fringes with regular arrangement of atom columns along the lattice arrays were clearly demonstrated in the crystalline particles of the calcified plaques. A number of characteristic granulo-fibrillar substructures in the amorphous phase could be seen to be tightly connected to the lattice-fringes in the crystalline phase along the interfaces between the amorphous and crystalline phases. The crystal lattices at the boundary between two crystals were very well matched with the periodicity of visible atoms continuous through the two crystals. The mineral elements such as calcium and phosphorus were detected to be diffusely distributed in the calcified matrix of the atherosclerotic plaques. Based on these findings, it is concluded that: (1) an interlacing network of granulo-fibrillar substructures in the amorphous matrix may play a structural and/or regulatory role for the organic matrix by providing sites for nucleation; and (2) the deposition of the mineral elements may be effective for the transformation of the amorphous nucleation phase to well-crystallized nucleation phase.

Aorta↗
PubMed1991

Decreased bone mineral density in patients with prolonged thyrotoxicosis before and after treatment.

To investigate the effects of prolonged thyrotoxicosis, we measured the bone mineral densities (BMD) of 24 untreated patients who had suffered from symptoms of thyrotoxicosis for at least 1 year. We also recruited 116 healthy Chinese women residing in the Taipei area as normal controls. The BMDs of these 24 patients for the whole body skeleton, lumbar spine, femoral neck, greater trochanter and Ward's triangle were all significantly lower than those of normal controls (one sample t-test, two-tailed alternative). Older patients had lower absolute values and a trend towards more severe bone loss, which was most significant at the femoral trochanter and Ward's triangle (p less than or equal to 0.05). The decrease in BMD was more pronounced in the vertebral bodies than in the proximal femur for all patients, implying predominantly trabecular bone loss in this disease. The BMDs of 10 patients were reevaluated 1 year after successful medical treatment. These 10 patients had remained euthyroid for 1 year with antithyroid drugs and showed a small, but significant, improvement in their BMDs at the lumbar spine and the proximal femur on reevaluation. However, the recovery was far from complete. Our findings suggest that thyrotoxicosis causes a remarkable loss of bone mineral, which cannot be compensated for after 1 year of successful treatment. Thus, early diagnosis and therapeutic intervention are important for preventing osteoporotic fractures, especially in elderly patients.

Adult↗
PubMed1991

Intracranial calcification and brachydactyly mimicking Albright's hereditary osteodystrophy in an adult patient with lingual thyroid and prolactinoma-like lesion.

Hyperprolactinemia and prolactinoma in patients with long-term primary hypothyroidism have been recognized for decades. We report a case of 57-year-old female patient with lingual thyroid and cretinism who had a high serum prolactin level (greater than 200 ng/ml) and a pituitary tumor with suprasellar and parasellar extension. The tumor regressed to a size undetectable by CT scan after 2 years of thyroid hormone replacement therapy, but complete normalization of the hyperprolactinemia required additional bromocriptine therapy. This patient showed generalized short metacarpal and phalangeal bones, calcification of the basal ganglia and dentate nuclei bilaterally, and subcutaneous calcification at both gluteal regions, while serum calcium, phosphorus and c-PTH levels were all normal. Thus in addition to short stature, brachydactyly, a round face, and obesity, which are related to hypothyroidism, she also presented features uniquely mimicking the Albright's hereditary osteodystrophy seen in patients with pseudohypoparathyroidism and pseudopseudohypoparathyroidism. Since she had no family history of pseudohypoparathyroidism and had a normal level of Gs alpha protein on the membrane of the red blood cells, there is no evidence of pseudopseudohypoparathyroidism. The cause of the ectopic calcification remains unknown.

Brain Diseases↗
PubMed1990

Transient ischemic attacks: their frequency in the Lehigh Valley.

The incidence of transient ischemic attacks (TIAs) in the Lehigh Valley was analyzed using the Lehigh Valley Stroke Register based on data collected between July 1, 1982, and June 30, 1986. The overall average annual incidence rate was 22.9 per 100,000 population, and 23.2 and 22.5 per 100,000 population in men and women, respectively. Men had a statistically significant higher age-specific rate of TIAs than women. Our incidence appears to be lower than that reported in earlier studies but, because of methodologic differences, only continued observations in our population and in similar populations using a standardized methodology will resolve the question of whether TIA frequency is, in fact, declining.

Adult↗