Measurement characteristics of two asthma symptom diary scales for use in clinical trials

The measurement characteristics of two asthma symptom diary scales developed for use as health outcome measures in clinical trials of asthma therapy were investigated. A daytime diary scale was designed to capture the frequency and inconvenience of daytime asthma symptoms and their effects on activities, and a nocturnal asthma symptom diary scale was designed to capture awakenings with asthma symptoms. The internal consistency, reliability, validity and responsiveness of both asthma diary scales were assessed in 346 adult asthma patients in two placebo-controlled clinical trials of an investigational asthma therapy, a leukotriene biosynthesis inhibitor. The daytime symptom scale showed sufficient internal consistency (0.90-0.92), and the daytime and nocturnal symptom scales showed sufficient test retest reliability (0.69-0.87). Construct validity was demonstrated by generally moderate-to-strong correlations for changes in the diary scales with changes in other measures of asthma status, such as forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and puffs of beta-agonist inhaler. Both scales demonstrated significant responsiveness to change in asthma due to therapy in one of the clinical trials. Based on these results, the daytime and nocturnal asthma symptom diary scales show measurement characteristics appropriate for use as asthma outcome measures in clinical trials of asthma therapy.

Measurement characteristics of two asthma symptom diary scales for use in clinical trials

The measurement characteristics of two asthma symptom diary scales developed for use as health outcome measures in clinical trials of asthma therapy were investigated. A daytime diary scale was designed to capture the frequency and inconvenience of daytime asthma symptoms and their effects on activities, and a nocturnal asthma symptom diary scale was designed to capture awakenings with asthma symptoms. The internal consistency, reliability, validity and responsiveness of both asthma diary scales were assessed in 346 adult asthma patients in two placebo-controlled clinical trials of an investigational asthma therapy, a leukotriene biosynthesis inhibitor. The daytime symptom scale showed sufficient internal consistency (0.90-0.92), and the daytime and nocturnal symptom scales showed sufficient test retest reliability (0.69-0.87). Construct validity was demonstrated by generally moderate-to-strong correlations for changes in the diary scales with changes in other measures of asthma status, such as forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and puffs of beta-agonist inhaler. Both scales demonstrated significant responsiveness to change in asthma due to therapy in one of the clinical trials. Based on these results, the daytime and nocturnal asthma symptom diary scales show measurement characteristics appropriate for use as asthma outcome measures in clinical trials of asthma therapy.

Pharmacokinetic and pharmacodynamic analysis of a novel leukotriene biosynthesis inhibitor, MK-0591, in healthy volunteers

1. The pharmacokinetic and pharmacodynamic properties of a novel 2-indolealkanoic acid derivative (MK-0591), a potent inhibitor of leukotriene biosynthesis, were investigated in healthy male Japanese volunteers. Single oral doses of 50, 125, 250 and 500 mg and multiple oral doses of 125 mg twice daily for 9.5 days and 250 mg once daily for 10 days were administered. 2. After the single-dose administration following overnight fasting, Cmax and AUC of MK-0591 in plasma increased in a dose-dependent manner, while elimination half-life remained constant (11.2-13.2 h) irrespective of dose. Food intake decreased Cmax and AUC by 71% and 68%, respectively, at a dose of 250 mg. With respect to multiple-dose administration before meals, there were no significant differences in the pharmacokinetic parameters between the first and last days, indicating a lack of significant accumulation of MK-0591 in plasma. Urinary recovery as the unchanged form was negligible throughout the study. 3. Ionophore-stimulated production of leukotriene B4 (LTB4) in blood ex vivo was inhibited significantly from 1 h until 12 to 48 h after single-dose administration as compared with predose value. In parallel, the urinary excretion of endogenous leukotriene E4 (LTE4) was significantly decreased from 4 to 8 h until 48 to 72 h after drug administration. Reduction of ionophore-stimulated LTB4 biosynthesis and urinary excretion of LTE4 following single administration of MK-0591 was statistically significant as compared with placebo group, and the duration of inhibition of LTB4 biosynthesis was dose-related.(ABSTRACT TRUNCATED AT 250 WORDS)

Blockade of leukotriene production by a single oral dose of MK-0591 in active ulcerative colitis

BACKGROUND

5-Lipoxygenase products of arachidonic acid metabolism are thought to play a central role in the secondary amplification of the inflammatory response in a number of human inflammatory diseases, such as ulcerative colitis. MK-0591 (3-(1((4-chlorophenyl)methyl)-3((1,1-dimethyl-ethyl)thio)-5(quinolin+ ++-2ylmethyl-oxy)-1H-indol-2yl)-2,2-dimethyl-propanoate) exerts its effect by binding to the 5-lipoxygenase activating protein, thereby inhibiting the translocation and activation of 5-lipoxygenase.

METHODS

Concentrations of leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) in rectal dialysis fluid, ex vivo biosynthesis of LTB4 in whole blood, and urinary excretion of leukotriene E4 (LTE4) from 16 patients with mild to moderately active distally located ulcerative colitis were measured by use of radioimmunoassays in a double-blind, placebo-controlled parallel-design study before and after oral administration of a 250 mg dose of MK-0591 or placebo.

RESULTS

The mean LTB4 concentration in rectal dialysis fluid was lowered after MK-0591 by > 90% (p < 0.05) from 4 to 8 hours, with a maximum inhibition of 97.5% +/- 3.4% (mean +/- SD) at 20 to 24 hours after dosing, whereas PGE2 was unchanged. In whole blood, MK-0591 decreased ex vivo biosynthesis of LTB4 (p < 0.01), with a maximum inhibition of 96.4% +/- 2.1% at 4 hours after dosing. Urinary excretion of LTE4 was reduced by more than 85% (p < 0.001) from 4 to 48 hours. No adverse events were observed.

CONCLUSION

These findings show that a single oral 250 mg dose of MK-0591 results in nearly complete blockade of systemic leukotriene production and LTB4 formation in the target tissue of inflammation (the rectum). Controlled multiple-dose trials to assess the clinical efficacy of this novel 5-lipoxygenase-activating protein inhibitor seem to be worthwhile.

The effect of MK-0591, a novel 5-lipoxygenase activating protein inhibitor, on leukotriene biosynthesis and allergen-induced airway responses in asthmatic subjects in vivo

BACKGROUND

The 5-lipoxygenase metabolites of arachidonic acid are likely to be involved in the pathophysiology of atopic asthma. We investigated the effect of pretreatment with MK-0591, a novel 5-lipoxygenase activating protein inhibitor, on allergen-induced early asthmatic reactions (EARs) and late asthmatic reactions (LARs), and subsequent airway hyperresponsiveness to histamine.

METHODS

Eight atopic men with mild to moderate asthma aged 19 to 31 years, (forced expiratory volume in 1 second [FEV1] > or = 67% of predicted value, histamine provocative concentration causing a 20% fall in FEV1 [PC20] < 4 mg/ml) and documented EAR and LAR to house dust mite extract participated in a two-period, double-blind, placebo-controlled, crossover study. During each study period histamine PC20 was measured 2 days before and 1 day after a standardized allergen inhalation challenge test. MK-0591 was administered in 3 oral doses of 250 mg each at 24, 12, and 1.5 hours before inhalation of allergen. Biochemical activity of MK-0591 was determined by calcium ionophore A-23187-stimulated leukotriene (LT)B4 biosynthesis in whole blood ex vivo and by urinary LTE4 excretion. Airway response to allergen was measured by FEV1 (percent fall from baseline). The EAR (0 to 3 hours) and the LAR (3 to 8 hours) were expressed as corresponding areas under the time-response curves.

RESULTS

MK-0591 and placebo did not differ in their effects on prechallenge FEV1 (p = 0.10). As compared with the value before pretreatment, MK-0591 blocked LTB4 biosynthesis and LTE4 excretion by a mean of 98% (range, 96% to 99%; p < 0.002) and 87% (range, 84% to 96%; p < 0.046), respectively, from 0 to 24 hours after allergen challenge. Both the EAR and the LAR were significantly reduced after administration of MK-0591 as compared with placebo, with a mean inhibition of 79% (p = 0.011) and 39% (p = 0.040), respectively. Allergen-induced airway hyperresponsiveness was not significantly different between the two pretreatment periods (p = 0.37).

CONCLUSIONS

In this study oral MK-0591 prevented leukotriene biosynthesis after allergen challenge in patients with mild to moderate asthma. The results of our study indicate that 5-lipoxygenase products play an important role during the EAR, whereas their contribution to the pathophysiology of the LAR seems to be of less importance.

A clinicopathologic study of ten patients with recurrent unexplained flushing

We describe the clinicopathologic features of 10 patients with recurrent unexplained flushing. These patients were referred to the National Institutes of Health with a diagnosis of mastocytosis or idiopathic anaphylaxis. Both diagnoses were eliminated after evaluation. Patients reported attacks of flushing lasting 15 minutes to 2 days and associated with such symptoms as anxiety, chest tightness, paresthesia, slurred speech, weakness, and pruritus. Abdominal pain was a constant feature, often associated with cramping and an increase in stool frequency. Attacks witnessed by physicians consisted of an exaggerated blush response of the face and upper part of the chest, and were sometimes associated with tachycardia, mild hypertension, and tachypnea. Hives, angioedema, wheezing, and hypotension were not observed. Routine laboratory studies and 5-hydroxyindoleacetic acid, vanillylmandelic acid, and plasma histamine levels were normal. Plasma histamine levels did not elevate during attacks. When performed, results of bone marrow examinations, skin biopsies, and bone scans were normal. Psychiatric examinations frequently revealed somatization disorders. Patients had often been prescribed a wide variety of medications including antihistamines, nonsteroidal anti-inflammatory drugs, and steroids, with little or no benefit. Despite the benign nature of the clinical and laboratory findings, patients had undergone repeated, often invasive, examinations for several years. Whether such patients have a prominent flush response exaggerated through a somatization disorder or a relatively benign flushing disorder associated with putative mediator release remains to be determined. Recognition of this category of patients with unexplained flushing will avoid subjecting such patients to unwarranted repeated examinations, procedures, and inappropriate therapy.

Comparison of azelastine and chlorpheniramine in the treatment of mastocytosis

BACKGROUND

Azelastine, a novel antiallergic medication, was compared with chlorpheniramine maleate for efficacy and safety in the treatment of systemic mastocytosis.

METHODS

Fifteen subjects with mastocytosis participated in a double-blind, randomized, three-period, crossover trial, which compared an azelastine regimen of 4 mg or 8 mg every 12 hours with a chlorpheniramine regimen of 12 mg every 12 hours. Response to therapy was assessed by daily symptom scores, extinction dilution skin tests, plasma histamine levels, and global evaluations.

RESULTS

Subjects' mean wheal area responses provoked by histamine or morphine sulfate were significantly lowered by azelastine when compared with chlorpheniramine. Plasma histamine levels in subjects receiving azelastine or chlorpheniramine were not significantly different. There were no significant differences between azelastine and chlorpheniramine in individual symptom scores or global evaluations except that azelastine at both doses significantly relieved pruritus and at 4 mg significantly relieved abdominal pain and that chlorpheniramine was associated with less fatigue in comparison to azelastine at 8 mg.

CONCLUSIONS

It thus appears that azelastine is superior to chlorpheniramine in suppressing skin responses to histamine and morphine sulfate and in suppressing pruritus in patients with mastocytosis. However, when all parameters are considered, neither drug is clearly superior for the treatment of patients with mastocytosis.

Oral leukotriene inhibitor (MK-886) blocks allergen-induced airway responses

To elucidate the role of leukotrienes (LT) in allergic asthma in humans the effect of MK-886, an LT biosynthesis inhibitor, was evaluated on antigen-induced early (EAR) and late (LAR) asthmatic reactions and bronchial responsiveness to histamine. Eight atopic men participated in a two-part, double-blind, placebo-controlled, crossover trial. MK-886 was administered in two oral doses of 500 mg and 250 mg, 1 h before and 2 h after allergen inhalation, respectively. Biochemical effects of MK-886 were evaluated by the inhibition of urinary LTE4 excretion and calcium ionophore-stimulated LTB4 biosynthesis in whole blood ex vivo. MK-886 significantly inhibited the EAR by 58.4% (AUC0-3 h) and the LAR by 43.6% (AUC3-7 h) when compared with placebo (p < 0.01). There was no difference in PC20 histamine 30 h post allergen challenge between MK-886 and placebo (0.33 and 0.27 doubling doses, p > 0.1). MK-886 inhibited calcium ionophore-stimulated LTB4 production in whole blood (54.2 +/- 25.6%) for up to 6 h post allergen challenge. LTE4 excretion in urine was inhibited by 51.5% during the EAR by as much as 80% during the LAR. This indicates that LT play a role in allergen-induced asthmatic reactions in humans in vivo and that LT synthesis inhibitors such as MK-886 should be further explored for the treatment of asthma.

Hematologic manifestations of systemic mast cell disease: a prospective study of laboratory and morphologic features and their relation to prognosis

PURPOSE

Systemic mast cell disease (SMCD) follows an indolent course in most patients, but a significant number of patients die of neoplastic hematologic disorders. Reviews of the literature and retrospective studies in a single institution have defined features that may be associated with a poor prognosis, but prospective studies have been lacking. Therefore, we prospectively analyzed the relationship between clinical, laboratory, and hematopathologic findings and clinical outcome in a series of 46 patients with mast cell disease. This analysis was employed to both define clinically useful prognostic variables and describe the histologic evolution of bone marrow mast cell infiltration and its relationship to hematologic neoplasia.

PATIENTS AND METHODS

Forty-six adult patients were referred to the National Institutes of Health (NIH) with clinical and/or pathologic evidence of mast cell proliferation. All patients had bone marrow examinations, and 10 patients underwent serial bone marrow biopsies. The diagnosis of SMCD required pathologic documentation of bone marrow mast cell infiltrates. The patients were followed for up to 13 years at the NIH (up to 30 years after the initial pathologic diagnosis of mast cell disease). Statistical analysis defined the correlation between variables and the presence of diagnostic bone marrow lesions. The Kaplan-Meier method was used to construct survival curves, and the effects of various variables on the survival time were examined.

RESULTS

Thirty-two of 46 patients (74%) had a bone marrow biopsy diagnostic for SMCD. The remaining 14 patients were considered to have cutaneous mast cell disease (CMCD). Univariate analysis showed that hepatosplenomegaly, alkaline phosphatase level, absolute lymphocyte count, and age at onset of symptoms were positively correlated with SMCD, whereas hemoglobin level was negatively associated with diagnostic bone marrow lesions. With multivariate analysis, only hemoglobin and absolute lymphocyte count remained as significant independent predictors of bone marrow findings. No CMCD patient died or had significant clinical deterioration in the 1- to 30-year period of follow-up (median = 8.5 years), whereas 10 of 32 SMCD patients (31%) died from 1 to 22 years after diagnosis (median = 2.5 years) (p less than 0.0001). Univariate analysis revealed the following variables as significantly increasing the risk of death in patients with SMCD: later onset of symptoms, absence of cutaneous mastocytosis, thrombocytopenia, elevated lactate dehydrogenase (LDH) level, anemia, bone marrow hypercellularity, qualitative peripheral blood smear abnormalities, elevated alkaline phosphatase level, and hepatosplenomegaly. Multivariate analysis showed that only the age at onset of symptoms and LDH levels were significant independent predictors of survival. Eight of the 10 SMCD patients who died had myeloproliferative or myelodysplastic syndromes or acute nonlymphocytic leukemia.

CONCLUSION

Our prospective study has defined a number of important variables in patients with clinical evidence of mast cell proliferation that can predict both the presence of SMCD and the likelihood of fatal disease. Since recent evidence suggests that mast cells derive from a bone marrow hematopoietic progenitor, SMCD may represent a myeloproliferative condition with the propensity to evolve into a neoplastic granulocytic disorder in a significant minority of patients.

Effects of tixocortol pivalate on gastrointestinal disease in systemic mastocytosis: a preliminary study

Tixocortol pivalate is a steroid reportedly without significant adrenal-pituitary axis suppression when administered via the gastrointestinal tract. To determine whether this steroid would suppress the gastrointestinal manifestations of systemic mastocytosis, we performed an open clinical trial for safety and efficacy with tixocortal pivalate in four patients for periods of 8-15 weeks. All patients showed a decrease in the symptoms of abdominal pain and frequency of stools. Laboratory parameters of malabsorption improved in parallel with symptom relief. Histopathologic abnormalities of the small bowel improved in one patient. There was no significant suppression of the pituitary-adrenal axis. Two patients developed fluid retention while on tixocortol pivalate, which was attributed to a mineralocorticoid effect. One patient had a fall in AM cortisol. In summary, this study strongly suggests that tixocortol pivalate, when administered orally, has gastrointestinal anti-inflammatory activity comparable to conventional steroids, but may not be entirely without adrenal-suppressive effect and may lead to fluid retention in some patients. Further studies are warranted to assess the value of tixocortol pivalate in the therapy of inflammatory diseases of the upper gastrointestinal tract.

The whole is greater than the sum of its parts: the anatomy of the Department of Veterans Affairs Medical District 17 Health Services Research and Development Field Program

The Medical District 17 Health Services Research and Development (HSR&D) Field Program was funded by the Veterans Administration (now the Department of Veterans Affairs--VA) in January 1983. This article describes the organization, progress, and accomplishments of this field program, and it provides a review of the breadth of health services research that is being conducted in Medical District 17. Overall, the field program has conducted research that addresses significant problems in the delivery of health care within the VA system. Resource utilization, cost effectiveness, and the care of geriatric patients have been some of the areas in which the Medical District 17 HSR&D Field Program has provided important research findings for VA. The field program plans to continue its response to the needs of VA. Moreover, HSR&D investigators will be collaborating with researchers of other services to conduct research that is both enlightening and highly relevant to the delivery of health care to the nation's veterans. The proposal for an HSR&D field program was developed by the Edward A. Hines Jr. VA Hospital in collaboration with the Center for Health Services and Policy Research (CHSPR) of Northwestern University. The program was funded in January 1983, as the result of a national competition to establish an HSR&D field program in each of the VA regions. The goals of the Medical District 17 Field Program are to improve the health care of veterans by conducting relevant research on the processes and outcomes of patient care; to provide comprehensive technical research assistance; and to educate VA managers, planners, and clinicians, as well as the general medical community, about advances in health care delivery. The field program's commitment to excellence is strengthened by its multidisciplinary approach, which enables physicians, nurses, social workers, psychologists, sociologists, economists, statisticians, administrators, and individuals in various related disciplines to cooperate in efforts to address a wide range of topical issues. These collaborations are a major strength of the field program. Primary research priorities of the field program are cost effectiveness of VA services (e.g., patient care technologies, delivery systems), long-term care, and rehabilitation. Investigators, however, are not limited to these topics and explore many other health services research issues of particular interest to them.

Analysis of plasma histamine levels in patients with mast cell disorders

PURPOSE

The use of plasma histamine determinations as a screening tool to distinguish patients with recurrent unexplained anaphylaxis, flushing, or both from those with mastocytosis has never been evaluated. This retrospective study was designed to determine if plasma histamine levels can be used as a screening test.

PATIENTS AND METHODS

Values of plasma histamine levels, measured using a sensitive radioenzymatic assay, from 41 patients with mastocytosis, 26 patients with recurrent unexplained anaphylaxis, and 76 normal subjects were statistically analyzed to determine diagnostic usefulness and accuracy. Patients with mastocytosis were subdivided into four smaller groups on the basis of clinical and histopathologic findings: (1) isolated urticaria pigmentosa, (2) indolent systemic mastocytosis, (3) mastocytosis with dysmyelopoiesis, and (4) lymphadenopathic mastocytosis with eosinophilia.

RESULTS

The distribution of plasma histamine values among patients with unexplained anaphylaxis strongly resembled that among the normal subjects (p greater than 0.50, Smirnov test), whereas patients with mastocytosis tended to show moderate to marked elevations above the upper limit of normal (617 pg/mL). The geometric mean plasma histamine levels in mastocytosis subgroups 2, 3, and 4 were found to be quite similar (1,085, 1,976, and 1,433 pg/mL; p greater than 0.50, F-test); moreover, each mean level was significantly greater than those of the normal subjects and of patients with unexplained anaphylaxis (p less than 0.01, Scheffé multiple comparison test). Analysis of the 27 sets of plasma histamine values collected on patients with indolent systemic mastocytosis revealed that the earliest value observed fell below 617 pg/mL in eight patients (30%). A similar analysis applied to the two earlier values indicated that both values would fall below 617 pg/mL in 9% of the patients. Data in four patients with mastocytosis demonstrated a diurnal variation in plasma histamine, with the highest values observed in the early morning (approximately 2:00 A.M.) and the lowest values in the afternoon (approximately 2:00 P.M.).

CONCLUSIONS

We conclude that, on average, patients with mastocytosis have elevated plasma histamine levels, whereas patients with unexplained anaphylaxis have plasma histamine levels within the normal range during asymptomatic periods; that plasma histamine levels in patients with mastocytosis exhibit a diurnal variation; and that plasma histamine determinations alone are not useful to screen patients for mastocytosis.

Diversification of health care services: the effects of ownership, environment, and strategy

The present findings suggest that the trend toward greater diversification of hospital services is likely to be most strongly influenced by state Medicaid policies and certain hospital characteristics. Increasing Medicaid eligibility and payment levels is likely to have a positive effect on services diversification. Growth in the number of inpatient services provided and a more severe case mix are also likely to be involved with greater service diversification. Affiliation with a not-for-profit hospital system is likely to be associated with more diversified hospital services but not affiliation with an investor-owned system. There is also some indication that the overall portfolio of services which a hospital offers in regard to market share and market growth characteristics influences diversification. Specifically, a low market share portfolio is likely to be associated with less diversification. Competition is likely to be associated with more diversification; particularly for hospitals belonging to systems. The effect of competition on hospital strategy and services diversification is a particularly important area for further investigation. Increasing Medicaid payment and eligibility levels are also likely to have a positive effect on the provision of services which are usually unprofitable. Raising such levels is likely to be particularly beneficial to inner-city hospitals who are already providing a greater number of such services. However, the present data suggest that investor-owned hospitals are least likely to provide such services. Increasing Medicaid eligibility levels is also likely to be associated with fewer services for which charity care has to be provided. State regulation in the form of rate review and certificate of need is likely to be associated with more services for which hospitals provide some charity care. But such policies alone do not deal with the larger issue of how to finance care for the medically indigent. Present data suggest the charity care issue may be particularly salient in markets characterized by a relatively high degree of competition. Finally, investor-owned hospitals provide as many services involving charity care as not-for-profit system hospitals, although investor-owned system hospitals provide fewer such services than not-for-profit freestanding hospitals. Throughout, the findings indicate the importance of distinguishing between ownership and system affiliation. Previous research has failed to make a distinction between ownership form and system affiliation, thus attributing to ownership form differences which, as present findings suggest, appear to be more associated with system affiliation.(ABSTRACT TRUNCATED AT 400 WORDS)