Stopping treatment or prescribing drugs that will shorten the patient's life is also being done in the US, so if you want to inflate the suicide numbers, you have to do it for all.
Don't they have health insurance ? Well, yes, but the Dutch government unilaterally changed the terms of national health insurance to no longer cover any treatment that isn't likely to "significantly" extend life, on average, and measured in percentage (and not for a particular patient). Of course significantly extending life is measured as a percentage, and if you're 80 ... Basic cheap treatment like dialysis is stopped at ~69 years old. And while it is true that it's unlikely to extend a patient's life by 10% from that point, stopping that treatment will be fatal in ~48 hours in some cases, and it'll be a painful death.