In 2018, 49 is the most common age for an American (U.S.) Denise who is registered female with the Social Security Administration. It is the 135th most common female first name for living U.S. citizens.
― Anonymous User 10/17/2018
1
It's also pretty common in the Netherlands where it's pronounced duh-NEE-suh. [noted -ed]
Also German:
https://www.beliebte-vornamen.de/4768-denise.htm
https://de.m.wikipedia.org/wiki/Denise
https://de.m.wiktionary.org/wiki/Denise
https://en.m.wiktionary.org/wiki/Denise#German
https://www.behindthename.com/name/denise/top/austria