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Biomedical subjects

C H Patrick

Publications and source records attributed to C H Patrick.

17 recordsLinked to original sources
PubMed1999

Frailty bias in comorbidity risk adjustments of community-dwelling elderly populations.

Our objective was to describe distortion in outcome studies due to "frailty bias" or differential susceptibility to adverse health outcomes due to frailties but attributed to other factors. We linked an administrative database to survey data (n = 5934) containing functional, condition, and outcome measures. The disease classification scheme of an empirically derived mortality model was used to categorize 7500 ICD-9-CM codes into five risk levels. Cox and logistic regressions were used to compare outcomes. Commonly employed measures differ in their sensitivity to detect and control frailty bias across a spectrum of major chronic diseases. Survival is inversely related to increasing functional impairment after adjusting for age, race, gender, education, number of comorbid conditions, and highest disease risk occurring during follow-up. Functional status appears to be a superior and essential element for control of the frailty bias that threatens comparability of outcome measures across community-dwelling populations containing chronically-ill disabled elderly.

Activities of Daily Living↗
PubMed1995

Therapeutic drug monitoring in neonates.

Therapeutic drug monitoring in neonates is challenging but valuable. Neonates have unique drug disposition that makes the use of adult guidelines sometimes inappropriate. This article reviews basic pharmacodynamics, unique neonatal factors, and the clinical applications of these principles. Factors that must be considered include different volumes of distribution, changing renal status, limited hepatic metabolism, and unique drug administration methods. Suggestions for altering drug dosages to achieve therapeutic and/or nontoxic blood concentrations are offered. An awareness of these principles makes drug monitoring in neonates rational and effective.

Drug Monitoring↗
PubMed1993

Long-term survival of veterans with traumatic spinal cord injury.

OBJECTIVE: To investigate the long-term survival of veterans with traumatic spinal cord injury (SCI). DESIGN: Survival in a retrospective inception cohort of veterans suffering service-connected traumatic SCI is compared with survival among veterans disabled by other conditions, survival among nondisabled veterans, and a population-based life table. SETTING: Subjects were identified from a national census of veterans with service-connected disabilities, using a selection algorithm based on disability codes. PATIENTS: A retrospective cohort of 5545 male veterans with traumatic SCI, surviving at least 3 months after injury, is compared with a stratified random sample of 7077 disabled veterans without SCI, a stratified random sample of 6967 nondisabled veterans, and a life table formed from similarly aged American males. MAIN OUTCOME MEASURE: Survival curves, extending from 3 months to 40 years after injury. RESULTS: The mean life expectancy of veterans suffering traumatic SCI and surviving at least 3 months is an additional 39 years after injury, 85% that of similarly aged American males. Although survival with traumatic SCI was comparable to that of the disabled control subjects for approximately 20 years after onset, a clear deficit occurred beyond this point. Older age at injury is a stronger predictor of poorer long-term survival than is complete quadriplegia. CONCLUSIONS: Among patients who survive the acute phase of their traumatic SCI, long-term survival is relatively good. Health care planners, providers, and communities should anticipate an increasing number of persons aging with SCI.

Adult↗
PubMed1992

Relatedness of strains of methicillin-resistant coagulase-negative Staphylococcus colonizing hospital personnel and producing bacteremias in a neonatal intensive care unit.

The emergence of methicillin-resistant coagulase-negative Staphylococcus as a major bacterial pathogen in neonatal intensive care units has stimulated interest in the epidemiology of spread of the organism. During a 12-month "epidemic" of bacteremias with methicillin-resistant coagulase-negative Staphylococcus we compared the characteristics of bacteremic and personnel nasally-carried strains by traditional and biomolecular methods. Sixty-two percent of neonatal intensive care unit nurses were colonized with methicillin-resistant coagulase-negative Staphylococcus with similar speciation to bacteremic strains. Inspection of plasmid profiles revealed a moderate degree of similarity between bacteremic and colonizing strains although genomic DNA restriction patterns showed diversity. Ribotype patterns were highly conserved (90%) in personnel strains. A 2.6-kilobase plasmid DNA probe hybridized to similarly sized plasmids and larger plasmids in one-half of the strains. We hypothesize that related methicillin-resistant strains may be transferred among personnel and neonates in the neonatal intensive care unit. Epidemiologic studies of coagulase-negative staphylococci should consider multiple molecular techniques to relate strains.

Bacteremia↗
PubMed1991

Prenatal care and prematurity: is there an association in uncomplicated pregnancies?

A retrospective investigation examined patterns of use of prenatal care and pregnancy outcomes (low birthweight and preterm births) in 6176 pregnancies without antepartum medical complications. Prenatal care use patterns differed significantly by mother's age, marital status, race, education, method of payment, and gravidity. By controlling for these differences through a logistic regression procedure, results showed that prenatal care was associated with significant reductions in the number of infants who were delivered preterm or had low birthweight. Fewer very low-birthweight (less than 1500 g) infants were among the preterm infants delivered to mothers with prenatal care compared with women who received no prenatal care. These data suggest that significant improvements in pregnancy outcomes are seen among women who use prenatal care, and these benefits occur in the absence of antepartum complications.

Adolescent↗
PubMed1990

The effect of bacteremia on automated platelet measurements in neonates.

Platelet volume measurements have been used to differentiate consumptive and hypoplastic thrombocytopenia. Since thrombocytopenia is a frequent complication of neonatal sepsis, the authors explored the utility of correlating mean platelet volume (MVP) and platelet distribution width (PDW) with bacteremia. In a sample of 156 infants, there was a significantly increased presence of bacteremia in those infants with MPV greater than 10.8 fL and/or PDW greater than 19.1%. High MPV and PDW showed high specificity for detecting bacteremia (95% and 79%, respectively), and had good negative predictive value. Neonates with blood cultures positive at birth (early infection) tended to have normal platelet volumes, while those infected after three days of age (late infection) had dramatic increases in MPV and PDW. Changes in MPV and PDW should be noted when the diagnosis of late sepsis is considered.

Age Factors↗
PubMed1988

Complication of prolonged transpyloric feeding: formation of an enterocutaneous fistula.

Enteral feeding tubes have been associated with perforations of the gastrointestinal tract, usually requiring surgical repair. A neonate with centronuclear myopathy developed an enterocutaneous fistula from the duodenum following prolonged placement of a transpyloric catheter. He did not require surgery and died later of unrelated complications.

Duodenal Diseases↗
PubMed1988

Stool water loss in very-low-birth-weight neonates.

Fluid requirements in very-low-birth-weight (VLBW) infants include compensation for renal, insensible (skin and lung), and stool losses and provision for fluid retained for growth. Current estimates of stool water losses in VLBW infants are based on measurements established in term neonates. Therefore, the water content of 24-hour stool collections were determined in 11 healthy VLBW male infants on full enteral feeds and compared to the working norms. The neonates in this study were less than 2 weeks old with a mean +/- SD birth weight and gestational age of 1,311 +/- 112 g and 30.8 +/- 1.5 weeks, respectively. They were receiving only enteral formula feedings of 100 ml/kg/day or more with no parenteral fluid supplementation. The mean +/- SD number of stools and water content of the stools was 2.7 +/- 2.0/day and 7.2 +/- 4.0 ml/kg/day, respectively. There was a significant correlation (r = 0.696, p less than 0.02) between gestational age at birth and number of stools per day, but the correlation between stool water loss per day, gestational age, volume of feedings per day, and birthweight was not significant. Based on this study, 7 ml/kg/day is a reasonable estimate of daily stool water loss in VLBW babies.

Feces↗
PubMed1987

Mean platelet volume and platelet distribution width in the neonate.

Normal values for mean platelet volume (MPV) and platelet distribution width (PDW) have not been firmly established for term and preterm neonates. Cord blood samples from 143 healthy newborns (78 full term and 65 premature) were analyzed with the Coulter counter. Platelet count and MPV were significantly greater (p less than 0.05 and p less than 0.001, respectively) in term versus preterm infants, while PDW was significantly less in term infants (p less than 0.001). Platelet count and MPV correlated with gestational age, and platelet count also correlated with birth weight. There was a significant (p less than 0.001) negative correlation of PDW with gestational age and birth weight. These data represent normal reference ranges for neonates and demonstrate significant variation with gestational age.

Blood Platelets↗
PubMed1987

Health differentials between blacks and whites: recent trends in mortality and morbidity.

Black Americans continue to have large numbers of premature and excess deaths, measured against white experience, from seven major causes. Major differences in chronic disease, disability and case fatality rates persist despite similarities in the amount of health care received; the nature and quality of care is likely to be dissimilar. Epidemiological and clinical evidence suggests various strategies to reduce these differentials through well-designed public health efforts at prevention. These will have to deal with harsh realities of sociocultural, economic, and political contexts.

Black or African American↗
PubMed1982

Sex differences in declining cohort death rates from heart disease.

We examined cohort mortality from heart disease (HD) at ages 40 and over for White men and women in the United States between 1945 and 1975. For each successive birth cohort from 1886 to 1890 and 1906 to 1910, female HD mortality rates exhibit a continuous decline with parallel slopes which shows no sign of abating in recent years. Among men, cohort HD mortality rates were increasing prior to 1965; since 1965, there has been a reversal of prior trends, i.e., each successive cohort has shown a decrease in HD mortality rates. None of the various hypotheses put forward to explain the recent decline in HD mortality provides a cogent explantation for the differential effects in men and women.

Adult↗
PubMed1980

Population impact of mortality reduction: the effects of elimination of major causes of death on the 'saved' population.

In this paper we examine the effects on life expectancy of elimination of 4 major causes of death. Methodologically, we compare the results of cause elimination under assumptions of pattern of failure elimination and assumptions of underlying cause elimination in a modified multiple-decrement life table framework for the segment of the population impacted. The 4 diseases selected for analysis are cancer, ischaemic heart disease, stroke, and diabetes, major killers among the elderly population. The degree to which life expectancy changes occur within the population from elimination of a given cause if a function of 3 factors: 1) distribution of age at death by cause for persons who die of that cause, 2) the gain in person years lived for those 'saved' from dying from that cause which has been eliminated, and 3) the proportion of all deaths which are due to the specific cause which is eliminated. Mortality data from the 1969 U.S. multiple cause mortality tapes from NCHS are analysed to determine the impact of life expectancy for males and females of both races when one of these 4 specific causes of death is eliminated.

Adolescent↗
PubMedDate not supplied

The Emory cubicle bed: an alternative to restraints for agitated traumatically brain injured clients.

As traumatically brain injured (TBI) clients emerge from coma, there may be transitory periods of agitation during which they pull at feeding tubes and intravenous catheters and thrash about, thus placing themselves at high risk of injury. During these periods, staff traditionally have resorted to restraints. But chemical restraints actually may be detrimental to cognitive recovery, and physical restraints often serve to increase agitation and foster dependence. Another approach is to modify the environment. The Emory cubicle bed, a modification of the Craig bed used at Craig Hospital in Colorado, allows for freedom of movement while blocking the client's field of vision. In reducing both tactile and visual stimulation, the bed also reduces agitation.

Beds↗
PubMedDate not supplied

Mortality model based on delays in progression of chronic diseases: alternative to cause elimination model.

For the analysis of the impact of major chronic diseases on a population, a life table model is proposed in which the age at death due to specific cause (chronic disease) is postponed. Even though many of the major causes of death related to intrinsic aging processes are impossible to eliminate, these causes might be significantly delayed or retarded. To illustrate the use of this model, the effects of a delay of 5, 10, and 15 years in deaths due to three chronic degenerative diseases (cancer, ischemic heart disease, and stroke) are calculated for specific race-sex components of the U.S. population in 1969. These calculations show that even moderate delays in the progression of major chronic diseases will yield a sizable portion of the total gain in longevity that would be available if the diseases were totally eliminated. Thus, they demonstrate that a life table model based on cause delay provides a more biomedically plausible representation of the health impact of a chronic disease on a population than does the cause elimination life table model. Additionally, the cause-delay model provides a mechanism for incorporating the likely effects of medical innovation on survival.

Actuarial Analysis↗
PubMedDate not supplied

Alterations in von Willebrand factor antigen in premature infants with respiratory distress syndrome and chronic lung disease.

Elevated levels of von Willebrand Factor Antigen (vWF:Ag) may occur in the presence of endothelial injury, a component in the pathology of acute pulmonary insufficiency. The vWF:Ag levels were examined in 13 well infants (controls) and 20 infants with respiratory distress syndrome (RDS), nine of whom developed bronchopulmonary dysplasia (BPD). All infants were very low birth weight (730 to 1500 g) and premature (25 to 34 weeks estimated gestational age). Plasma samples were obtained at birth and weekly through 28 days of age and frozen at -70 degrees C. The vWF:Ag was quantified by the enzyme linked immunosorbent assay (ELISA) method for 138 plasma specimens; in addition, 77 samples were analyzed for multimer pattern by SDS-agarose (1.7 percent) electrophoresis and densitometric scanning. All groups had elevated mean levels of vWF:Ag, compared to adults. Although levels remained stable over the four week period, the group of infants with BPD had a significantly high mean level of vWF:Ag at 21 days than those groups without BPD (p < 0.05). Visual examination of vWF multimer patterns revealed absence of unusually large vWF multimers and triplet patterns suggestive of increased proteolytic degradation of von Willebrand factor. However, densitometer scanning revealed that samples with higher vWF:Ag levels (> 200 percent) had increased amounts of moderate to smaller sized multimers, regardless of presence or absence of BPD. It is our conclusion that von Willebrand factor antigen levels are nonspecifically elevated in premature infants and that chronic lung disease is associated with even higher plasma values, possibly owing to pulmonary endothelial injury.

Antigens↗