Is psoriasis linked to other diseases?

Yes. Patients with psoriasis have a higher risk of developing skin cancers and cardiovascular disease. For this reason, it is recommended that those with psoriasis get general skin checks at least once yearly, and establish care with a primary care doctor to monitor cholesterol and be educated on heart disease prevention.
Yes . More and more it is linked to the "metabolic syndrome" including hypertension , increased lipids and obesity. Also arthritis and some auto-immune diseases.