Factors Associated With PIM use in the Frail Elderly: A Cross-sectional Study

Background: The use of potentially inappropriate medications (PIM) by the elderly is commonly studied, but studies evaluating the use of PIM by frail elderly covered by prepaid health plans are still lacking. Objective: To identify the prevalence of use and the factors associated with the use of PIM by the elderly patients with high and moderate risk of clinical-functional vulnerability, according to the Beers criteria 2019. Methods: A cross-sectional study was developed with elderly people from a private health plan in Vitória-ES, Brazil. Socioeconomic, demographic and clinical data were collected through a digital platform and a structured questionnaire through an interview, from October 2018 to June 2019. The association between the use of PIM and independent variables was verified by univariate logistic regression with their respective confidence intervals (CI) 95%. The Multiple Model included the variables with P ≤ .20. Results: 332 elderly patients were interviewed (mean age 81.5 years, gender 237 female, 95 male). A 65% prevalence of PIM use was identified. In the multiple logistic regression model, the variables associated with the use of PIM were self-medication (P = .004), high risk of clinical-functional vulnerability (P = .022), use of psychotropic medications (P = .000001), musculoskeletal medications (P = .04) and alimentary tract medications (P = .03). Physical exercises were considered a protection factor (P = .02). Conclusion: The high prevalence of PIM use indicates the need for improvement in elderly private health care, to increase pharmacotherapy safety for this population.

Immunomodulatory activity of Tityus serrulatus scorpion venom on human T lymphocytes

Background

Tityus serrulatus scorpion venom (TsV) contains toxins that act on K⁺ and Na⁺ channels and account for the venom’s toxic effects. TsV can activate murine peritoneal macrophages, but its effects on human lymphocytes have been poorly investigated. Considering that lymphocytes may play an important role in envenomation, we assessed whether TsV affects the expression of phenotypic (CD3, CD4, and CD8) and activation (CD69, CD25, and HLA-DR) markers, cell proliferation, and cytokine production in peripheral blood mononuclear cells.

Methods

Cytotoxicity of TsV was evaluated via the MTT assay. Cell proliferation, expression of phenotypic and activation markers, and release of cytokines were assessed using flow cytometry, after treatment with non-cytotoxic concentrations of TsV. The combined use of carboxyfluorescein diacetate succinimidyl ester and monoclonal antibodies against phenotypic and activation markers enabled us to simultaneously assess cell proliferation extent and cell activation status, and to discriminate among cell subpopulations.

Results

TsV at concentrations of 25 to 100 μg/mL were not cytotoxic towards peripheral blood mononuclear cells. TsV did not induce significant changes in lymphocyte subpopulations or in the expression of activation markers on CD4⁺ and CD8⁺ T cells. TsV inhibited the phytohemagglutinin-stimulated lymphocyte proliferation, particularly in the CD8⁺ CD25⁺ T lymphocyte subset. TsV alone, at 50 and 100 μg/mL, did not induce peripheral blood mononuclear cell proliferation, but elicited the production and release of IL-6, a proinflammatory cytokine that plays an important role in innate and adaptive immune responses.

Conclusions

TsV is a potential source of molecules with immunomodulatory action on human T lymphocytes.

Electronic supplementary material

The online version of this article (doi:10.1186/s40409-015-0046-3) contains supplementary material, which is available to authorized users.