Implications of Drug Therapy in the Elderly

Acute salicylate poisoning: risk factors for severe outcome

CONTEXT

Salicylate poisoning remains a significant public health threat with more than 20,000 exposures reported annually in the United States.

OBJECTIVE

We aimed to establish early predictors of severe in-hospital outcomes in Emergency Department patients presenting with acute salicylate poisoning.

METHODS

This was a secondary data analysis of adult salicylate overdoses from a prospective cohort study of acute drug overdoses at two urban university teaching hospitals from 2009 to 2013. Patients were included based on confirmed salicylate ingestion and enrolled consecutively. Demographics, clinical parameters, treatment and disposition were collected from the medical record. Severe outcome was defined as a composite occurrence of acidemia (pH <7.3 or bicarbonate <16 mEq/L), hemodialysis, and/or death.

RESULTS

Out of 1997 overdoses screened, 48 patients met inclusion/exclusion criteria. Patient characteristics were 43.8% male, median age 32 (range 18-87), mean initial salicylate concentration 28.1 mg/dL (SD 26.6), and 20.8% classified as severe outcome. Univariate analysis indicated that age, respiratory rate, lactate, coma, and the presence of co-ingestions were significantly associated with severe outcome, while initial salicylate concentration alone had no association. However, when adjusted for salicylate concentration, only age (OR 1.13; 95% CI 1.02-1.26) and respiratory rate (OR 1.29; 95% CI 1.02-1.63) were independent predictors. Additionally, lactate showed excellent test characteristics to predict severe outcome, with an optimal cutpoint of 2.25 mmol/L (78% sensitivity, 67% specificity).

CONCLUSIONS

In adult Emergency Department patients with acute salicylate poisoning, independent predictors of severe outcome were older age and increased respiratory rate, as well as initial serum lactate, while initial salicylate concentration alone was not predictive.

Probing the interaction of human serum albumin with bilirubin in the presence of aspirin by multi-spectroscopic, molecular modeling and zeta potential techniques: insight on binary and ternary systems

Here, we report on the effect of aspirin (ASA), on the binding parameters with regard to bilirubin (BR) to human serum albumin (HSA). Two different classes of binding sites were detected. Binding to the first and second classes of the binding sites was dominated by hydrophobic forces in the case of HSA-BR, whereas in the case of the ternary system, binding to the first and second classes of the binding sites was achieved by electrostatic interaction. The binding constant (K(a)) and number of binding site (n) obtained were 1.6 × 10(6)M(-1) and 0.98, respectively, for the primary binding site in the case of HSA-BR, and 3.7 × 10(6)M(-1) and 0.84, respectively, in the presence of ASA (ternary complex) at λ(ex)= 280 nm. The progressive quenching of the protein fluorescence as the BR concentration increased indicated an arrangement of the domain IIA in HSA. Changes in the environment of the aromatic residues were also observed by synchronous fluorescence spectroscopy (SFS). Changes of the secondary structure of HSA involving a decrease of α-helical and β-sheet contents and increased amounts of turns and unordered conformations were mainly found at high concentrations of BR. For the first time, the relationship between the structural parameters of HSA-BR by RLS for determining the critical induced aggregation concentration (C(CIAC)) of BR in the absence and presence of ASA was investigated, and there was a more significant enhancement in the case of the ternary mixture as opposed to the binary one. Changes in the zeta potential of HSA and the HSA-ASA complex in the presence of BR demonstrated a hydrophobic adsorption of this anionic ligand onto the surface of HSA in the binary system as well as both electrostatic and hydrophobic adsorption in the case of the ternary complex. By performing docking experiments, it was found that the acting forces between BR and HSA were mainly hydrophobic > hydrogen bonding > electrostatic interactions, and consequently BR had a long storage time in blood plasma, especially in the presence of ASA. This was due to the electrostatic interaction force between the BR and HSA being stronger in (HSA-ASA) BR than in the HSA-BR complex. In addition, it was demonstrated that, in the presence of ASA, the first binding site of BR on HSA was altered, but the parameters of binding did not become significantly modified, and thus the affinity of BR barely changed with and without ASA.

Disease-Modifying Antirheumatic Drug Use in the Elderly Rheumatoid Arthritis Patient

During the 10-year period since the last review was done by Gardner and Furst, studies have furthered the knowledge of the use of disease-modifying antirheumatic drugs (DMARDs) in the elderly rheumatoid arthritis (RA) patient. This article briefly reviews the clinical pharmacology of humans as they age, and details the effects of aging on the specific pharmacokinetics and responses to commonly used DMARDs. There has been some progress in understanding the elderly RA patient; however, data are insufficient to provide much confidence in DMARDs effects in the elderly.

Disease-modifying antirheumatic drug use in the elderly rheumatoid arthritis patient

During the 10-year period since the last review was done by Gardner and Furst, studies have furthered our knowledge of use of disease-modifying antirheumatic drugs (DMARDs) in the elderly rheumatoid arthritis (RA) patient. This article will briefly review the clinical pharmacology of human as they age, and detail the effects of aging on the specific pharmacokinetics and responses to commonly used DMARDs. There has been some progress in understanding the elderly RA patient, however, there is insufficient data for much confidence in DMARDs effects in the elderly.

Clinical spectrum and treatment of rheumatic syndromes in the elderly

Rheumatic diseases in the elderly are common and may be more difficult to diagnose than in younger patients. Treatment must be tailored to the patients' needs and functional reserve. Elderly patients need to be monitored even more closely for toxicity than younger adults.

The basis for variability of response to anti-rheumatic drugs

The reasons for variability of response to anti-rheumatic drugs are myriad. All the factors that contribute to kinetic variability, for example, contribute to differences in response between individuals. Thus, differences in drug formulation, protein binding, drug metabolism and excretion, all contribute to variable responses. Further, factors which contribute to differential clinical response/toxicity must be considered. Here, age, gender, genetic background, weight, concomitant diseases and numerous environmental factors come into play. Among the environmental factors are such diverse elements as smoking, activity and diet. Finally our ability to measure change, be it in response or toxicity, is limited, introducing apparent variability (as much as real variability) into the equation. While we cannot, at present, delineate the contribution of each factor to individual variability, it is hoped that systematic, persistent effort will help us understand and then control these elements, leading to improved ability to individualize therapy and decrease the variability of response to anti-rheumatic drugs.

Drug treatment of pain in rheumatoid disorders

The relief of pain remains a delicate balance between the potential toxicity and desired effect of currently available compounds. Physician and patient need to make the optimum use of such therapies. Control of pain and stiffness in rheumatic diseases is a dynamic process. There is a constant need for re-appraisal of aims and objectives and adjustment of treatment according to variations in disease and response. Where 'specific' therapy is available, it is clearly preferable to use it rather than employ large doses of purely symptom-relieving drugs. At present toxicity is inextricably linked to efficacy, and dissociation of these two factors seems unlikely to be achieved in the near future. More efficient 'targeting' of drugs at the site of desired action should help to minimize the adverse effects of therapy. Ultimately the most efficient way of relieving pain and stiffness will be to prevent or suppress the inflammatory disorders which give rise to the symptoms. Unfortunately this is an elusive goal at present.