Hi Kathy,
Mr. Gracie's primary cause of death was diabetes and he spent his final days in a diabetic coma. Apparently he was never well after the Titanic experience and although it would be quite a stretch to claim that that "caused" diabetes, the stress of the whole thing may have served to exacerbate other infirmities. In a legal document I obtained concerning his wife,Constance--and this document was filed many years after her husband died--there is a notation stating "husband died Dec. 4th, 1913 (sic) in New York City after being wrecked in SS Titanic disaster." There was probably an element on her part of "wanting" to associate her husband's death with the tragedy as well. After all, death associated with Titanic would be much more dramatic/heroic than stating something like "my husband succumbed to diabetes at the age of 63."
I hope this helps.
Phillip