Comparison of the effect of two types of short message service (interactive and non-interactive) on anticoagulant adherence of patients with prosthetic heart valves

One of the major complications of valve replacement، is valve dysfunction wich occurs in thrombolytic complication and systemic embolism. Therefore، these patients should take anticoagulant with warfarin. Incorrect use of anticoagulant is the cause of thrombotic complications and bleeding in patients with mechanical valves due to very low levels of adherence to the medication. This research was done with the perpose of comparison of the effect of two types of short message service (interactive and non-interactive) on patient compliance with anticoagulant regimens in patients with prosthetic heart valves. This study is a clinical trial performed on 90 eligible patients referred to Imam Khomeini hospital in Tehran، Iran for a perdiod of three months. The patients were divided into three groups of 30 patients، contorol، interactive and non-interactive. Self-report questionnaires were completed and International Normalized Ratio (INR) levels were recorded. Educational leaflets were given to all of the patients، their phone numbers were taken and they were instructed about using short message service. The control group did not receive SMS. Four educational messages were sent to the non-interactive group every week for a period of three months. In the interactive group، in addition to sending educational messages، patients were able to communicate with the researcher and ask their questions. After three months، all three groups completed the self-report questionnaires again. Then anticoagulant adherence was evaluated using questionnaire and INR levels. Data were analysed using fisher exact test، Chi-Square، paired T test، and analysis of variance. Before the intervention all three groups did not have a significant difference in the mean of drug (P=0. 43) and diet (P=0. 84) adherence. But three months after intervention، three groups had significant differnece in the mean of the anticoagulant adherence (P≤0/001). The mean of adherence in interactive group was higher than the other two groups after intervention. PT and INR between three groups did not indicated any significant differences (P=0. 18). Paired T test results showed that after the intevention PT and INR in the non-interactive with (P=0. 008) and in interactive group with (P≤0/001) had significant mean and in control group the differences was not significant (P=0. 9). Using interactive short message service can increase anticoagulant adherence of patients with prosthetic heart valves.