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R Roubenoff

Publications and source records attributed to R Roubenoff.

At least 91 records · Page 5Linked to original sources
PubMed1994

Sensitivities of noninvasive tests for central nervous system vasculitis: a comparison of lumbar puncture, computed tomography, and magnetic resonance imaging.

OBJECTIVE: To determine the sensitivities of lumbar puncture (LP), computed tomography (CT), and magnetic resonance imaging (MRI) for central nervous system (CNS) vasculitis. METHODS: We reviewed the charts and radiologic studies of 20 patients with angiogram positive CNS vasculitis. RESULTS: The patients ranged in age from 7-72 years, with a mean of 43.7 +/- 15.5 years. Twelve patients (60%) were women; 8 (40%) were men. Seven had primary angiitis of the CNS (PACNS), 8 had rheumatological illnesses (4 had systemic lupus erythematosus), and 5 had vasculitis due to other diverse etiologies, including 2 who had CNS infections. LP was positive in 8/15 angiographically proven cases, for a sensitivity of 53% [95% confidence interval (CI): 27-79]. The sensitivity of CT was 65% (11/17) (95% CI: 38-86), and that of MRI 75% (12/16) (CI: 48-93). The use of LP plus either CT or MRI was more sensitive than LP alone: for LP and CT, the sensitivity was 92% (11/12) (CI: 62-100), and for LP and MRI, 100% (12/12) (CI: 74-100). The combination of CT and MRI was not more sensitive than either test alone. CONCLUSION: The sensitivities of LP, CT, and MRI for angiogram positive vasculitis are only modest. CT and MRI may be completely normal in cases of CNS vasculitis when the angiogram is positive. LP and either CT or MRI are of additive benefit in the diagnosis of CNS vasculitis, and should be done before angiography; and, in a patient with both a normal LP and a normal CT or MRI, a CNS angiogram is unlikely to be positive for vasculitis.

Adolescent↗
PubMed1993

Advantage of knee height over height as an index of stature in expression of body composition in adults.

It is not clear how body composition should best be compared between subjects, but it is accepted that simply comparing total mass or percentage fat-free mass (FFM) or fat mass (FM) is not adequate. Indexing body composition to stature seems more appropriate, but the decline in height with age or osteoporosis could confound comparisons of body composition across age or disease groups. Using bioimpedance data from 600 adults in the Framingham Offspring Study, we examined the ability of height and knee height indexes to correctly describe the loss of FFM seen with increasing age between 28 and 75 y. Indexing body composition to height obscured the loss of FFM with age (r = -0.065, P < 0.26 for men; r = -0.050, P < 0.394 for women), whereas indexing body composition to knee height preserved the correct information (r = -0.154, P < 0.007 for men; r = -0.161, P < 0.006 for women). These data suggest that knee height is a reliable surrogate for stature and should be used to adjust body composition measurements when bioimpedance is used to estimate body composition.

Adult↗
PubMed1993

Hormones, cytokines and body composition: can lessons from illness be applied to aging?

Loss of lean body mass (LBM) is a hallmark of aging and of acute and chronic illness. Loss of more than 40% of lean mass is not compatible with life. The causes of loss of LBM in aging remain obscure, although changes in growth hormone production, physical activity and the cytokines interleukin-1 beta and tumor necrosis factor-alpha may play a role. The usefulness of a disease model based on rheumatoid arthritis (RA) is considered, in which all these changes occur to a greater degree and independently of age. RA is a common autoimmune condition in which cytokine production is increased, LBM is reduced and mortality is greatly accelerated. These observations suggest that, with respect to body composition at least, RA represents a model of "accelerated" aging. A hypothesis is presented that unifies metabolic and immunologic observations and changes in body composition. The interrelationship of the immune system and body composition is an important area that deserves further investigation.

Adult↗
PubMed1993

Humoral mediation of changing body composition during aging and chronic inflammation.

A decline in lean body mass and an accompanying increase in fat mass are known to occur during aging. The consequences of these changes in body composition may include decreased strength and physical activity, altered energy metabolism, and impaired resistance to infection. The mechanisms behind these age-related events remain unknown, but they may include changes in some of the hormonal and cytokine mediators that seem to regulate body composition. The common inflammatory condition rheumatoid arthritis could provide a useful model of these phenomena dissociated from chronological aging. This article reviews changes in neuroendocrine and immune modulators of metabolism and their consequences during aging and chronic inflammation.

Aging↗
PubMed1993

Interactions between nutrition and infection with human immunodeficiency virus.

Nutritional status is severely compromised in persons infected with the human immunodeficiency virus (HIV). One or a combination of several disease-related factors can contribute to substantial weight loss and malnutrition, accelerating the downhill course of the disease. Efforts to prevent weight loss should include early intervention aimed at appetite stimulation, nutritional supplementation with high-calorie, high-protein oral supplements, and diagnosis and treatment of underlying infections and malabsorption. Although enteral or parenteral feedings may be warranted, these forms of nutritional support pose special problems in HIV-infected persons, and the ultimate benefits of these measures are not yet clear. The recent use of pharmacologic agents to stimulate appetite or improve body composition shows promise, but more research is needed before these drugs can be widely recommended as adjuncts to therapy. In general, unproven remedies should be avoided, as their risks may well outweigh their benefits.

Body Composition↗
PubMed1992

Cutaneous manifestations of the eosinophilia-myalgia syndrome.

We report the cutaneous manifestations of the eosinophilia-myalgia syndrome in 10 patients, with specific reference to their clinical course, histopathological features, and immunogenetic studies. Cutaneous manifestations could be classified into three groups: morphoea-like sclerosis, urticarial and papular lesions, and generalized sclerosis. Despite this polymorphic clinical presentation, the histopathological abnormalities in all cases were strikingly similar, and consisted of superficial and deep perivascular lymphocytic dermal infiltrates, mucin deposition, and fascial inflammation (often in the absence of sclerosis). Immunoperoxidase studies revealed increased numbers of factor XIIIa- and MAC 387-positive cells in the inflammatory infiltrate. Immunogenetic studies demonstrated that 77% (7/9) of patients possessed the HLA-DR3 or HLA-DR4 phenotypes. Mean follow-up of 24 months after discontinuation of L-tryptophan revealed the presence of persistent severe disabling disease in 30% of patients.

Adult↗
PubMed1992

Rheumatoid cachexia: depletion of lean body mass in rheumatoid arthritis. Possible association with tumor necrosis factor.

OBJECTIVE: To investigate body composition and serum tumor necrosis factor (TNF) levels in a series of 24 patients with rheumatoid arthritis (RA). METHODS: Body composition assessment by anthropometric measures and bioelectrical impedance. Cytokine determination in serum by ELISA: RESULTS: When compared to United States population norms, 16 of the subjects (67%) were cachectic. In regression models, lean body mass (LBM) was inversely associated with the number of swollen joints (p < 0.025). Elevated TNF-alpha was found in 3 of 5 flaring patients vs 0 of 18 patients with less active disease (p = 0.001). These 3 were all cachectic, while the 2 flaring patients without detectable TNF had normal LBM (p < 0.03). Among the whole group, there was a trend toward increasing disability with decreased LBM after adjusting for joint pain and disease duration (p < 0.07). CONCLUSION: Cachexia is common in RA, and may be cytokine driven. Given the prognostic impact of LBM wasting in other diseases, the effect of rheumatoid cachexia on outcome in RA deserves further study.

Adult↗
PubMed1992

Central nervous system angiography: safety and predictors of a positive result in 125 consecutive patients evaluated for possible vasculitis.

To determine the complication rate of cerebral angiography and to identify variables associated with angiograms positive for vasculitis, we retrospectively evaluated 125 consecutive patients who had angiography because of possible central nervous system (CNS) vasculitis. Sixteen of 125 (12.8%) had angiograms positive for CNS vasculitis. Fourteen (11.5%) experienced a transient and 1 (0.8%) had a persistent neurologic deficit due to angiography. The complication rates between patients who were angiogram positive and angiogram negative did not differ (p greater than 0.05). Two clinical variables were significant risk factors for having an angiogram positive for CNS vasculitis: a preexisting rheumatic disease diagnosis (relative odds 3.39, 95% CI 1.08-10.62, p less than 0.033) and an abnormal lumbar puncture (relative odds 5.50, 95% CI 1.13-26.64, p less than 0.031). We conclude that the risk of persistent neurologic complications from angiography is low in patients who have or are suspected of having CNS vasculitis.

Adult↗
PubMed1991

Incidence and risk factors for gout in white men.

OBJECTIVE: To identify potentially modifiable risk factors for the development of gout. DESIGN: Longitudinal cohort study (The Johns Hopkins Precursors Study). PARTICIPANTS: Of 1337 eligible medical students, 1271 (95%) received a standardized medical examination and questionnaire during medical school. The participants were predominantly male (91%), white (97%), and young (median age, 22 years) at cohort entry. OUTCOME MEASURE: The development of gout. RESULTS: Sixty cases of gout (47 primary and 13 secondary) were identified among 1216 men; none occurred among 121 women (P = .01). The cumulative incidence of all gout was 8.6% among men (95% confidence interval, 5.9% to 11.3%). Body mass index at age 35 years (P = .01), excessive weight gain (greater than 1.88 kg/m2) between cohort entry and age 35 years (P = .007), and development of hypertension (P = .004) were significant risk factors for all gout in univariate analysis. Multivariate Cox proportional hazards models confirmed the association of body mass index at age 35 years (relative risk [RR] = 1.12; P = .02), excessive weight gain (RR = 2.07; P = .02), and hypertension (RR = 3.26; P = .002) as risk factors for all gout. Hypertension, however, was not a significant risk factor for primary gout. CONCLUSIONS: Obesity, excessive weight gain in young adulthood, and hypertension are risk factors for the development of gout. Prevention of obesity and hypertension may decrease the incidence of and morbidity from gout; studies of weight reduction in the primary and secondary prevention of gout are indicated.

Adult↗
PubMed1991

The meaning and measurement of lean body mass.

Methods of measuring lean body mass have evolved greatly in the past decade. Because all practical methods of measurement are indirect (i.e., not involving carcass analysis), appropriate models of body composition must be applied. Today's improved precision is due both to better instrumentation and to improved models based on partition of the body into its constituent compartments. With this improved methodology has come the recognition that loss of lean body mass is associated with survival in starvation, acute illness, and aging. In addition, correlations of lean body mass with immune competence and functional status are beginning to emerge. It remains to be proven that changes in lean body mass in aging and disease independently determine outcome. Interventions that preserve or normalize lean body mass could be important for preservation of vigorous functional status.

Adult↗
PubMed1990

Oral cimetidine improves the accuracy and precision of creatinine clearance in lupus nephritis.

OBJECTIVE: To determine whether short-term use of oral cimetidine improves the precision of creatinine clearance (CCr) and reduces the overestimation of glomerular filtration rate (GFR) that occurs with this test in patients with lupus nephritis (because creatinine is secreted by injured renal tubular cells). DESIGN: Double-blind, placebo-controlled, crossover clinical trial. PATIENTS: Thirteen patients with lupus nephritis with mild renal insufficiency (mean serum creatinine, 230 mumol/L [2.6 mg/dL]; median, 106 mumol/L [1.2 mg/dL]). INTERVENTIONS: Patients were given placebo or cimetidine tablets, 400 mg four times daily for 2 days, with ambulatory 24-hour urine collection during the second 24 hours ("outpatient study"). Simultaneous 4-hour technetium-99-diethylenetriamine penta-acetic acid (Tc99-DTPA) and CCrs were measured immediately after each 24-hour collection ("simultaneous study"). MEASUREMENTS AND MAIN RESULTS: Use of cimetidine improved the accuracy of CCr, as measured by the CDTPA-to-CCr ratio (1.07 [cimetidine] compared with 1.33 [placebo]; P less than 0.05). Cimetidine use also improved the precision of CCr (P less than 0.05). In addition, when compared with standard clinical estimators of GFR, creatinine clearance with cimetidine rendered the most precise estimates of GFR and explained more of the variation in GFR estimation than did any other method (R2 = 0.78 compared with R2 = 0.52 to 0.63). These effects were shown under both simultaneous and outpatient conditions. No side effects due to cimetidine occurred. CONCLUSIONS: In patients with lupus nephritis, the cimetidine-aided CCr offers a compromise between the precise and accurate but expensive and inconvenient research techniques (inulin, iothalamate, or DTPA clearances) and the grossly inaccurate and imprecise but convenient technique (CCr) for determining GFR.

Adult↗
PubMed1990

Eosinophilia-myalgia syndrome due to L-tryptophan ingestion. Report of four cases and review of the Maryland experience.

Eosinophilia-myalgia syndrome (EMS) is a recently described clinical entity that has been ascribed to taking over-the-counter preparations of the amino acid L-tryptophan. We describe 4 patients with EMS, 3 of whom presented with eosinophilic fasciitis, and we review the epidemiology of EMS reported in Maryland and discuss the possible pathophysiology of the disease. EMS should be considered in the differential diagnosis of severe myalgia, eosinophilia, and eosinophilic fasciitis.

Administration, Oral↗
PubMed1990

Catabolic effects of high-dose corticosteroids persist despite therapeutic benefit in rheumatoid arthritis.

Although corticosteroids (CS) cause nitrogen wasting in healthy humans, it is not known whether the salutary antiinflammatory and appetite-stimulating effects of CS in inflammatory diseases mitigate this effect. We measured nitrogen balance before, during, and after 3 d of high-dose methylprednisolone therapy in nine patients with flare-ups of rheumatoid arthritis. There was evidence of preexisting somatic protein and fat depletion in seven of nine subjects. Patients were allowed to eat freely on a metabolic ward. Nitrogen balances were -0.89 +/- 1.38 g/d (means +/- SEM) before CS therapy, -5.77 +/- 1.30 g/d during therapy (P less than 0.001), and -3.54 +/- 1.38 g/d after therapy (P less than 0.01) despite increased energy and nitrogen intake and clinical resolution of inflammation during and after the pulse therapy. We conclude that patients with rheumatoid arthritis are often cachectic and high-dose CS cause nitrogen wasting in these patients despite an antiinflammatory and appetite-stimulatory benefit.

Adrenal Cortex Hormones↗
PubMed1990

Gout and hyperuricemia.

The prevalence of gout in the United States has been rising steadily for the past two decades. Hyperuricemia is considered a necessary but not sufficient precondition for gout. Known risk factors for gout include male sex, hypertension, renal insufficiency, obesity/weight gain, diuretic use, lead exposure, and family history. The association of gout and hyperuricemia with coronary artery disease is controversial. Current evidence from the Framingham Study suggests that gout is in fact an independent risk factor for CHD. These data suggest that patients with gout should be screened for modifiable risk factors for CHD, and that early intervention in such patients may be worthwhile. Finally, the effect of AHU as risk factor for CHD remains unclear but is probably a weak one.

Gout↗