Currently i'm migrating www. prefix from my urls and use htaccess to do the job. Since we have new software and cleaned database some of the old urls doesnt exists anymore.

Therefore some requests redirect to 404 page.

1. www.domain.com/old-page # htaccess redirect to non-www url, 301
2. domain.com/old-page # page does not exists, 404

Does this method have any SEO issues, or even affect pagerank?

Or should i check the page existence before redirecting and show 404 without redirect?