Background Helminth infection may influence cardiometabolic risk through effects on inflammation and metabolism. We hypothesised that helminths are protective and their treatment detrimental to metabolic outcomes. Methods We conducted a cluster-randomised trial in 26 fishing communities, Lake Victoria, Uganda. We investigated effects of community-wide intensive (quarterly single-dose praziquantel, triple dose albendazole) versus standard (annual single-dose praziquantel, six-monthly single-dose albendazole) anthelminthic treatment on metabolic outcomes, and observational associations between helminth infection and metabolic outcomes. The primary outcome, homeostatic model assessment of insulin resistance (HOMA-IR) and secondary outcomes (including blood pressure, fasting blood glucose and lipids) were assessed in a survey conducted after four years of intervention among individuals ≥10 years. Results We analysed 1898 participants. The intervention had no effect on HOMA-IR (adjusted geometric mean ratio [95%CI] 0.96 [0.86,1.07] p=0.42) but resulted in higher mean LDL-cholesterol in the intensive arm (2.86 vs 2.60 mmol/L, adjusted mean difference [95%CI] 0.26 [-0.03,0.56] p=0.08). Lower LDL-cholesterol levels were observed in S. mansoni (2.37 vs 2.80 mmol/L, -0.25 [-0.49,-0.02] p=0.04) and Strongyloides infected (2.34 vs 2.69mmol/L, -0.32 [-0.53,-0.12] p=0.003) participants compared with uninfected. S. mansoni infection was associated with lower total cholesterol levels (4.24 vs 4.64 mmol/L, -0.25 [-0.44,-0.07] p=0.01). Participants with moderate to heavy S. mansoni infection had lower triglycerides, LDL-cholesterol and diastolic blood pressure levels. Conclusions Helminth infections improve lipid profiles and may lower blood pressure. Further studies to confirm causality and investigate mechanisms will contribute to understanding the epidemiological transition and may suggest new approaches to prevent cardiometabolic disease. Clinical trials registration ISRCTN47196031

BACKGROUND: Rheumatic heart disease (RHD) remains a major public health concern in developing countries, and routine screening has the potential to improve outcomes. Standard portable echocardiography (STAND) is far more sensitive than auscultation for the detection of RHD but remains cost-prohibitive in resource-limited settings. Handheld echocardiography (HAND) is a lower-cost alternative. The purpose of this study was to assess the incremental value of HAND over auscultation to identify RHD.

Despite reductions in S. mansoni intensity and hookworm prevalence, intensive MDA had no effect on atopy, allergy-related disease or helminth-related pathology. This could be due to sustained low-intensity infections, thus a causal link between helminths and allergy outcomes cannot be discounted. Intensive community-based MDA has limited impact in high-schistosomiasis-transmission fishing communities, in the absence of other interventions.