HTLV-1 infection and its association with long-term chronic disease progression: evidenced by a 10-year follow-up study

Human T-lymphotropic virus type 1 (HTLV-1), a delta retrovirus, infects 10–20 million people worldwide. Persistent infection can cause systemic inflammation, increasing susceptibility to comorbidities. While research has focused on cardiovascular disease (CVD), HTLV-1’s association with other chronic conditions remains unclear. The current study aims to investigate long-term disease progression in HTLV-1 patients to address this gap. This cohort study was conducted on the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD study). This information pertains to a sample of 7,560 participants who completed the follow-up. These participants included 7,320 healthy individuals and 241 patients who had contracted HTLV-1. After ten years of follow-up, various chronic health conditions were measured and analyzed. The results of the present study indicated that subjects with HTLV-1 had a higher risk of CVD and chronic kidney disease (CKD). No significant differences were observed between HTLV-1-positive and HTLV-1-negative participants in the incidence of diabetes, anemia, metabolic syndrome, obesity, anxiety, or depression. The risk of CVD and CKD among HTLV-1-positive individuals was 1.420 (RR: 95% CI 1.013–2.002, P = 0.04) and 1.281 (OR: 95% CI 1.080–1.521, P = 0.003), respectively. HTLV-1 infection increases the risk of chronic disease, especially CVD and CKD. In this regard, it seems that following subjects with HTLV-1 is necessary. Further research is needed to elucidate the mechanisms by which HTLV-1 contributes to chronic diseases, and prevention strategies are necessary to reduce the incidence of these chronic diseases.