Halsey is suffering from Lupus and a rare lymphoproliferative disorder.
The singer, 29, who was born Ashley Nicolette Frangipane and uses she/they pronouns, took to Instagram on Tuesday (June 4) to tell fans of their struggle with serious medical issues ahead of the release of their fifth studio album, but did not specify which conditions.
They have now updated fans in a thank you note for their support on Instagram by detailing what conditions they have been fighting.
Referencing the release of her new single, Halsey said: "Thank you guys for the unbelievable amount of love for The End and the support you've shown me since its release.
"I realise everyone is catching up with news I've held in for a very long time, and I wasn't sure how much I wanted to share
"You've all been so kind so I want to share a bit more. In 2022, I was first diagnosed with Lupus SLE and then a rare T-cell lymphoproliferative disorder.
"Both of which are currently being managed or in remission; and both of which I will likely have for the duration of my life.
"After a rocky start, I slowly got everything under control with the help of amazing doctors.
"After two years, I'm feeling better and I'm more grateful than ever to have music to turn to.
"I can't wait to get back where I belong: With you all (grey heart emoji) Singing and screaming my heart out."
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease in which the immune system of the body mistakenly attacks healthy tissue.
Lymphoproliferative disorders are a group of diseases that cause an uncontrolled production of lymphocytes, a type of white blood cell.
Halsey told their fans in her post on Tuesday they were "lucky to be alive" due to her ongoing health issues, alongside a carousel of images and videos that included one of them lying in hospital hooked to a drip.
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