Constipation and hypofunction of the thyroid gland Myth or reality?

Abstract

Thyroid disorders are very common diseases. Their prevalence increases with age, and women are affected more often. The wide range of clinical symptoms traditionally includes evacuation disorders, i.e. constipation in patients with hypothyroidism and diarrhoea in patients with thyretoxicosis. However, a search of literature reveals that there is a paucity of evidence-based publications confirming constipation as a frequent symptom of hypothyroidism. In order to find a causal relationship between hypothyroidism and constipation, three conditions would have to be present: a higher prevalence of constipation in patients with hypothyroidism, the presence of specific abnormalities such as longer transit time in patients with hypothyroidism, and finally the effectiveness of substitution therapy. However, the data fulfilling these three conditions are missing in evidence-based medicine. Neither do our data confirm constipation as a frequent symptom of hypothyroidism. In summary, hypothyroidism is a rare finding in patients with isolated constipation and testing of the thyroid function in these patients is not beneficial.