Can thyroid nodules cause hypothyroidism?

Occur together: It is probably more likely that the nodules happen to occur along with hypothyroidism, i.e., whatever caused the hypothyroidism cause the nodules as well. Multinodular goiter is a possibility along with prior thyroiditis.

Nodules hypothyroid: The most common cause of low thyroid is autoimmune Hashimoto's thyroiditis. The lumps in the thyroid can and do exist with the Hashimoto's but don't cause the underlying problem. It is possible that a thyroid gland can become so full of thyroid nodules that it becomes unfunctional, but this is unusual.