INFORMATION ON US CITIZENS HELD IN WWII
MILITARY
There were 130,201 US Military captured and interned in WWII. As of January 1st 2002, 39,719 or 13.5% were still alive. Of the total count of US POWs in WWII 36,260 were captured and interned by the Japanese. On January 1st 2002, 6,327 were still alive (17.4%). Here is the grim news; the comparison of those POWs held by Germany versus Japan. Median age of WWII POWs on January 1st 2002 was 81.


U.S. MILITARY HELD BY NAZIS BY JAPANESE
Captured & Interned 93,941 36,260
Died While POW 1,121 (1.1%) 12,951 (35.7%)
Alive on January 1st 2002 33,392 (35.5%) 6,327 (17.4%)

CIVILIANS
There were 18,745 US Civilians captured and interned in WWII. As of January 1st 2002, 2,705 or 14.4% were still alive. Of the total civilian internees in WWII 13,996 were captured and interned by the Japanese. On January 1st 2002, only 1,290 were still alive (9.2%). Again, here are the grim statistics; the comparison of U.S. civilians interned by Germany versus those held by Japan. Median age of WWII Civilian Internees on January 1st 2002 was 84.


U.S. CIVILIANS HELD BY NAZIS BY JAPANESE
Captured & Interned 4,749 13,996
Died While POW 168 (3.5%) 1,536 (11%)
Alive on January 1st 2002 1,415 (29.7%) 1,290 (9.2%)

(These are the official figures provided by CFIR, Inc. 2002)


don't think this was exactly what you were looking for... I shall keep looking.