A study published this week in Mayo Clinic Proceedings confirms that Parkinson’s disease can, perhaps surprisingly, increase the risk of melanoma. The researchers also show that the link is a two-way relationship, with melanoma also suspected to increase the risk of Parkinson’s. The study was carried out by Mayo clinic researchers. Their analysis showed that individuals with Parkinson’s disease were four times more likely to have a history of melanoma. Also, people with melanoma had four times the risk of developing Parkinson’s.