TOKYO, Aug. 24 (Reuters) - Japan's Prime Minister Shinzo Abe wants to take care of his health and do his utmost at his job, he said on Monday (Aug 24), after a second hospital visit within days sparked concern whether he could stay on as leader of the world's third-biggest economy.

The visit came as Japan's longest-serving prime minister surpassed a record for longest consecutive tenure as premier set by his great-uncle Eisaku Sato half a century ago, adding to speculation Abe could resign after reaching the milestone.

Abe, criticised for his handling of the coronavirus outbreak and some scandals, has suffered a slide in voter support to one of the lowest levels since returning to office for a second term in 2012 with promises to revive the economy and bolster defence.

"I'd like to take care of my health and do my best at my job," Abe told reporters at his official residence, after visiting a Tokyo hospital where he said he had received results of an exam done last week and undergone additional examinations.

Abe, who turns 66 next month, also said he wanted to speak again later about his medical tests.

Earlier, government spokesman Yoshihide Suga said Abe was having a follow-up to a check a week ago when his examination lasted 7 1/2 hours, fuelling worries about his health.

But major broadcaster Nippon TV said Abe was being treated for a chronic illness rather than a check-up, citing multiple unidentified government and ruling party sources.

Abe has been prime minister since 2012 in his second stint after a troubled term from which he resigned abruptly in 2007, because of struggles with ulcerative colitis, a disease he now keeps in check with medicine that was not previously available.