I think yes. What kind of problems he was having, I don't know....
In the video Loving The Alien, he has a nosebleed in one scene, and is shaking, presumably from cocaine. I always wondered at this. Was it just a reference to: his past cocaine use; how his drug use in the '70's still haunts him; that he was using cocaine at the time?? It's not unbelievable.....he's rich, so he can certainly get it, and I don't believe he came out of Berlin completely cured. My guess is he's had a few relapses.
There were rumours of drug use during NLMD. Like that one lyric (from Time Will Crawl?): I saw a stream full of wide-eyed fish, and a man with no eyes at all. Or something like that. That seems to suggest drug use to me(hallucinations.)
Ashes to Ashes is about drug use too, and that was in 1980.
I don't know half of you half as well as I should like; and I like less than half of you half as well as you deserve