Efficacy of probiotics in patients of cardiovascular disease risk: A systematic review and meta-analysis

This meta-analysis examined the effect of probiotics on outcomes associated with cardiovascular disease risk factors (high blood pressure, overweight BMI, high cholesterol and triglycerides, elevated HbA1c and serum glucose). All randomised controlled trials publish on PubMed, Scopus, Embase, Grey Literature and the Cochrane Central Register of Controlled Trials (CENTRAL) from 1990 to 2020 were systematically searched. The PEDro scale was used to assess the quality of studies. A total of 34 studies with 2177 adults were selected for inclusion in the analysis. The mean difference and effect size with a 95% confidence interval (CI) were analysed for the pooled results. Statistically significant pooled effects of probiotics were found in the reduction of systolic and diastolic blood pressure, total cholesterol, LDL-C, serum glucose, HbA1C and BMI; and elevation of HDL-C. No significant changes were observed in the outcome of triglycerides. Subgroup analysis revealed statistically significant effects of probiotics on the treatment of risk factors, with results favouring longer duration of treatment (> 1.5 months), use of alternate formulations (kefir and powder), higher dosage of probiotics (> 1.0 × 109 CFU), lower rate of study attrition (< 15%), double blinding of the study, diabetic patients and female populations. In summary, our meta-analysis showed a highly significant reduction in SBP, DBP associated with type 2 diabetes and in patients with diabetes mellitus, milk intake and more than 1.5 months duration intake. The effect on the reduction of total cholesterol LDL-C was associated with diabetes, hypertension, hypercholesterolemia, yoghurt intake and less than 1.5 months probiotic intake. The effect on the reduction of glucose and HbA1c was associated with diabetes, small dosage of probiotics, milk type and less than 1.5 months duration intake. Additionally, probiotic supplement had a beneficial effect in reducing BMI associated with obesity, higher dosage intake of probiotics and more than 1.5 months duration of intake.