The aim of this review was to summarize the evidence on the effectiveness of Leech therapy in treatment of cardiovascuLar diseases. This assessment is based on the analysis of results of clinical trials conducted in 2000-2015 and published in peer-reviewed literature indexed in PubMed, ISI Web of Science, Scopus, E-library.ru and E-library.kz databases. The paper presents a review of the current controlled and uncontrolled studies ensured evidence-based information about the effectiveness of leech therapy in the treatment and prevention of complications of coronary heart disease, hypertension, chronic heart failure and stroke. In discussion, we demonstrate the rationale for leech therapy from the evidence-based point of view. We conclude that the current evidence is considered sufficient for using leech therapy as a complementary method in treatment of cardiovascular diseases and prevention of their complications as a part of the conventional therapy. According to the official recommendations on the use of leech therapy in healthcare issued by the Ministry of Health of the Russian Federation from 2002, the list of indications for leech therapy include coronary heart disease, early stages of heart failure, cardiosclerosis, cardialgias, dyscirculatory encelopathy and arterial hypertension. However, leech therapy should not be used as a substitute for standard treatment schemes of the abovementioned conditions.

Leech therapy is one of the most commonly used methods of complementary medicine. In Kazakhstan, leech therapy is officially recognized method of rehabilitation, however, no studies describing patients of leech therapy clinics or factors associated with compliance with this treatment with original data from Kazakhstan have been published yet. The aim of this study is to present socio-demographic characteristics of patients receiving leech therapy and assess factors associated with compliance with leech therapy in Kazakhstan. This is a cross-sectional study which includes all patients who attended the clinic "Hirudo" (Almaty, Kazakhstan) from July 2012 through December 2014. Data were collected from medical records and by interviews performed by the first author. Independent associations between predictors and the compliance to treatment were assessed by multiple binary logistic regression. Adjusted odds ratios (aOR) with 95 % confidence intervals (CI) were calculated. Cardiovascular patients comprised 67,5 % of all patients during the study period. Pensioners were the most common social group (41,7 %). The main factors associated with compliance with leech therapy were lower costs compared to standard treatment (aOR = 25,3; 95 % CI: 17,2-37,3), satisfaction by the quality of care (aOR = 4,0; 95 % CI: 1,8-19,6) male gender (aOR = 1,5; 95 % CI: 1,0-2,2) and married status (aOR = 6,4; 95 % CI: 4,1-10,2). We also observed an inverse association between patients' age and compliance. Thus, compliance with leech therapy among Kazakhstani patients is mainly determined by lower costs compared to standard treatment and subjective satisfaction by the quality of care. Men and married patients are also more likely to comply with this treatment. However, we emphasize that the evidence needed for such an extensive use of leech therapy as in Kazakhstan is still missing warranting further research by means of well-designed clinical trials.