BACKGROUND: Common measures of adherence to prescribed medications derived from administrative databases reflect both patients' and physicians' behavior, even if the measures are often interpreted as reflecting only the patient's adherence. Adherence to inhaled corticosteroids (ICSs) has been shown to be low among patients with asthma.

OBJECTIVE: To develop a new measure of patients' adherence adjusted for prescription patterns and to evaluate the extent to which the low use of ICSs in asthma is due to patients' nonadherence or suboptimal prescribing practices.

METHODS: The new measure of adherence, called the proportion of prescribed days covered (PPDC), is defined as the ratio of the total days' supply dispensed to the total days' supply prescribed during the study period. The PPDC is a modification of an existing adherence measure, the proportion of days covered (PDC).The PPDC and PDC for ICSs, therapy that should be prescribed for chronic daily use to patients with persistent asthma, were compared within a cohort of 4190 ICS-naïve patients with asthma aged 18-45 years derived from the administrative health databases of Quebec, Canada. We estimated the mean and the 95% confidence interval of the PPDC and PDC for ICSs over 1 year, and we calculated the part of nonadherence attributed to patients when measured with the PDC that can be attributed to nonoptimal prescribing of ICSs for chronic daily use with the following formula: [(1 - PDC) - (1 - PPDC)] / (1 - PDC).

RESULTS: The mean PPDC and PDC during the 1-year study were 52.6% (95% CI 51.6 to 53.6) and 19.1% (95% CI 18.6 to 19.6), respectively. Forty-one percent of nonadherence attributed to patients when measured with the PDC could be, in fact, attributed to nonprescribing of ICSs for chronic daily use.

CONCLUSIONS: Our new adherence measure, the PPDC, may be considered as another way to assess patient adherence, taking into account differing prescribing patterns.

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BACKGROUND: A significant proportion of patients with asthma have persistent symptoms despite treatment with inhaled glucocorticosteroids.

OBJECTIVE: We hypothesized that in these patients, the alveolar parenchyma is subjected to mast cell-associated alterations.

METHODS: Bronchial and transbronchial biopsies from healthy controls (n = 8), patients with allergic rhinitis (n = 8), and patients with atopic uncontrolled asthma (symptoms despite treatment with inhaled glucocorticosteroids; mean dose, 743 μg/d; n = 14) were processed for immunohistochemical identification of mast cell subtypes and mast cell expression of FcεRI and surface-bound IgE.

RESULTS: Whereas no difference in density of total bronchial mast cells was observed between patients with asthma and healthy controls, the total alveolar mast cell density was increased in the patients with asthma (P < .01). Division into mast cell subtypes revealed that in bronchi of patients with asthma, tryptase positive mast cells (MC(T)) numbers decreased compared with controls (P ≤ .05), whereas tryptase and chymase positive mast cells (MC(TC)) increased (P ≤ .05). In the alveolar parenchyma from patients with asthma, an increased density was found for both MC(T) (P ≤ .05) and MC(TC) (P ≤ .05). The increased alveolar mast cell densities were paralleled by an increased mast cell expression of FcεRI (P < .001) compared with the controls. The patients with asthma also had increased numbers (P < .001) and proportions (P < .001) of alveolar mast cells with surface-bound IgE. Similar increases in densities, FcεRI expression, and surface-bound IgE were not seen in separate explorations of alveolar mast cells in patients with allergic rhinitis.

CONCLUSION: Our data suggest that patients with atopic uncontrolled asthma have an increased parenchymal infiltration of MC(T) and MC(TC) populations with increased expression of FcεRI and surface-bound IgE compared with atopic and nonatopic controls.

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Adequate assessment of adherence to medical treatment is critical for both research purposes and clinical practice. This study examined the factor structure and longitudinal invariance of the Medication Adherence Report Scale (MARS-A10) in a sample of asthmatic patients.

We examined longitudinal data from 294 inner-city, adult participants with moderate to severe asthma. Because of ambiguous evidence regarding the dimensionality of the MARS-A10, the data was analysed with exploratory structural equation modelling. We first proceeded by determining the dimensionality of the scale at baseline and examined whether the structure, loadings, intercepts and errors were invariant over the four assessments points. Results indicated that a two-factor structure (factor 1: non-adherence based on experiential changes; factor 2: non-adherence based on intentional medication avoidance) had the best fit to the data (χ(2)(25) = 37.69, p = 0.05). Longitudinal analyses revealed that the nine items assessing intentional non-adherence were invariant over time. The evidence from the factor analysis suggests that intentional non-adherence is a multidimensional construct.

Additionally, longitudinal data provided strong evidence that the items examining intentional non-adherence are invariant over time, indicating that changes in non-adherence scores can be validly attributed to changes in behaviour.

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Most lung cancer patients with skeletal metastases have a short survival and it is difficult to identify those patients who will benefit from palliative surgery.

We report complication and survival rates in a consecutive series of lung cancer patients who were operated for symptomatic skeletal metastases.

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