On August 28, four days after he set the record for the longest consecutive tenure of a Japanese prime minister, Shinzo Abe suddenly announced his resignation. Despite rumours about his health, he seemed to catch even his closest colleagues off guard.

In explaining his decision, Abe cited recurrence of ulcerative colitis, which also forced him to resign from his first stint in the top job in 2007. Yet a number of other factors must have weighed on Abe’s prime ministership before his health issues came to the fore.