Factors associated with non-adherence to the treatment of vivax malaria in a rural community from the Brazilian Amazon Basin

Abstract

Introduction:We investigated the association between demographic and behavioral factors and non-adherence to antimalarial therapy. Methods: A demographic questionnaire and 5-item self-reported questionnaire regarding non-adherence were completed by 135 patients after treatment for Plasmodium vivax. Results: Treatment interruption, but not demographic factors, was significantly associated with non-adherence to therapy. The likelihood of non-adherence was 5.16 times higher when the patients felt better than when they felt worse. The relative risk of parasitic resurgence was 3.04 times higher in non-adherent patients. Conclusions: Treatment interruption is significantly associated with treatment adherence.Keywords: Malaria. Resurgence. Adherence.The failure of chloroquine and primaquine to treat malaria by Plasmodium vivax has recently increased worldwide, including in the Brazilian Amazon Basin, where the treatment is not effective for an estimated 4-15% of patients. Parasitic resurgence after treatment completion is commonly associated with resistance of P. vivax strains against antimalarial drugs, the relapse of hypnozoites, reinfection in endemic areas, or inadequate exposure to antimalarial drugs, which can be the result of low-quality drugs, incorrect dosage, drug interactions, vomiting or other gastrointestinal disorders, and non-adherence to the prescribed regimen (4) (5) (6) .The latter is a challenge for the control and eradication of the disease, because the exposure of the parasite to subtherapeutic concentrations of antimalarial drugs can lead to infection recrudescence and the selection of resistant strains. Non-adherence has been associated with demographic and behavioral variables, such as education level, gender, age, level of knowledge about the disease and its prevention, adverse effects, poor interaction between patients and their dispensers, loss of drugs, perceived ineffectiveness of the drug, and difficulty accessing health facilities (4) (5) (6) .In a previous study that aimed to validate a 5-item selfreported questionnaire for the estimation of non-adherence to antimalarial drugs, 33.2% of the participants in the riverside community of the Amazon Basin were non-adherent; however, the factors responsible for the non-adherence were not determined (7) . To improve disease control and eradication efforts, it would be helpful to understand the causes of non-adherence (5) ; therefore, the current study aimed to evaluate the association between non-adherence and demographic and behavioral factors and to estimate the risk of parasitic resurgence in non-adherent patients during the follow-up period.A prospective study was conducted from September to October 2012 at the Basic Unit Health in Anajas, State of Pará, a rural municipality on Marajo Island (0º59'21" S and 49º56'24" W), where the transmission of malaria is intense, with some seasonal fluctuations throughout the year. We randomly recruited adults with slide-confirmed infection by P. vivax among those who spontaneously sought care in...

Publics’ Malaria Knowledge, Prevention and Treatment Practices, A Cross-sectional Survey From Khartoum, Sudan

“…The results showed that there was no signi cant relationship between patients demographics and their compliance with antimalarial drugs treatment and that was consistent with the ndings of a study carried out in Uganda [28]. Stopping treatment after symptoms improvement [29] and upon the development of ADRs [30] was shown in some studies and it was found that drug knowledge and previous experience of drug use were signi cant predictors of adherence to treatment [31]. Patient education on noncompliance to treatment and its drawbacks not only for the patients but also for the whole country as a risk of drug resistance is very crucial.…”

Evaluation of the Effect of Supervised Antimalarial Treatment on P. Vivax Malaria Recurrences

“…In Pará, Brazil, the relative risk of parasitic resurgence was 3.04 times higher in non-adherent patients (19). Other study reported that adherence frequency was 86.4% (81.7%-90.1%) (20).…”

Evaluation of the effect of supervised anti-malarial treatment on recurrences of Plasmodium vivax malaria

“…In the Brazilian Amazon region, treatment is not supervised and there are few studies that discuss the importance of adherence and the often-precarious conditions of dispensing and storing medications can contribute negatively [ 19 ]. In the state of Pará, Brazil, one study reported that the relative risk of parasitic resurgence was 3.04 times higher in patients that did not adequately adhere to treatment, and also reported that adherence frequency was 86.4% (81.7%–90.1%) [ 20 ].…”