When the latest hiatus was first announced last August 2014, the reason cited was that the manga author was experiencing severe back pains and that the hiatus will only last 2 weeks.
However, a week later, Jump! announced that the hiatus will last longer because Togashi was still experiencing back pains, though they did say that he is already receiving medication.
After some time, the manga’s return to last “indefinitely,” which fans kinda expected as the name Yoshihiro Togashi is known for his long and frequent hiatuses which often last for more years.
But regardless of what you believe, whether you believe he is truly having health problems or you believe he is just priming up his next “excuse” for is next hiatus, Hunter x Hunter readers are now worried that the manga might go into another long hiatus given the trend of Togashi’s author comments.