Incidence and risk factors of hypothyroidism in patients with hematological malignancies compared to healthy population: a systematic review and meta-analysis

Previous literature has reported hypothyroidism as a long-term endocrine complication in hematological malignancy (HM) patients. Nevertheless, there is a lack of a comprehensive study determining the incidence of hypothyroidism in this population. We aimed to systematically investigate the incidence compared to the healthy population and determine the significant risk factors. We conducted a systematic search of PubMed, Scopus, and Web of Science for studies published up to April 2025. Eligible studies were analyzed using a random-effects model to estimate pooled incidence rates. Heterogeneity across studies was assessed using the I² statistic. Subgroup analyses were performed to explore the impact of specific risk factors, and publication bias was evaluated using funnel plots and Egger’s test. This study included 32 studies and revealed a significantly higher incidence of hypothyroidism in HM patients with pooled risk estimates of 5.47 (95% CI: 3.11; 9.61, P-value < 0.0001), with the highest pooled risk estimates in patients with lymphoma with an HR of 8.62 (95% CI: 3.79; 19.57, P-value < 0.0001). Additionally, several significant risk factors, such as female sex, chemotherapy, radiotherapy (RT), total body irradiation (TBI), and white ethnicity, have been identified as significantly associated with hypothyroidism incidence. In contrast, no significant correlation between cGVHD, alkylating agent, cyclophosphamide, donor source, nodular sclerosing, the stage, and stem cell source and incidence of hypothyroidism was observed. This meta-analysis demonstrates that patients with HMs are at significantly increased risk for developing hypothyroidism. These findings highlight the importance of early screening and endocrine management in high-risk patients.