The same island holds the National Sanatorium Nagashima Aiseien.

As of December 2, 2005, the Oku-Kōmyō-En housed 252 residents (131 males and 121 females).

The sanatorium, built in the Kanzaki River delta valley, was hit by the Muroto typhoon on September 21, 1934.

The storm left 2,702 dead and 334 missing, including 187 people in the sanatorium (173 patients, 3 employees, and 11 family members).

The number of inpatients in a given year depends not only on those newly hospitalized and the recently deceased, but also on other factors such as patient escapes and discharges, depending on the conditions of the times.