Increased risk for incident thyroid diseases in people with psoriatic disease: A cohort study

Background: The association between psoriasis and thyroid diseases is unclear. Objective: To examine the risk for thyroid diseases among psoriasis patients. Methods: We used Taiwan's National Health Insurance Research Database to conduct a nationwide cohort study. We examined the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for incident thyroid diseases in relation to psoriasis and psoriatic arthritis. Results: We identified 13,266 patients with psoriatic arthritis (psoriatic arthritis group), 149,576 with psoriasis alone (psoriasis group), and 162,842 nonpsoriasis controls. Compared with the nonpsoriasis controls, the psoriatic arthritis and psoriasis groups had increased risk for incident hyperthyroidism (aHR 1.32, 95% CI 1.07-1.65 [psoriatic arthritis]; aHR 1.22, 95% CI 1.11-1.33 [psoriasis]) and Graves disease (aHR 1.38, 95% CI 1.07-1.79 [psoriatic arthritis]; aHR 1.26, 95% CI 1.13-1.41 [psoriasis]). Both groups also had increased risk for incident hypothyroidism (aHR 1.74, 95% CI 1.34-2.27 [psoriatic arthritis]; aHR 1.38, 95% CI 1.23-1.56 [psoriasis]) and Hashimoto thyroiditis (aHR 2.09, 95% CI 1.34-3.24 [psoriatic arthritis]; aHR 1.47, 95% CI 1.18-1.82 [psoriasis]). Limitations: Lack of data on psoriasis severity. Conclusion: People with psoriatic disease are associated with an increased incident thyroid diseases, including hyperthyroidism, hypothyroidism, thyroiditis, Graves disease, and Hashimoto thyroiditis. Endocrinology consultation may be considered when psoriasis patients present with thyroid symptoms.