I think the positive effects for physical exercise in cognition and hypertension are fairly well known.
There are other factors like alcohol consumption and stress have high correlation on the downside as well.
I have a family history of alzheimer's and have hypertension so have a personal interest in looking after my mental health.
What I can recommend from personal experience is:
1) Regular exercise with a routine designed by a fitness trainer.
2) No alcohol, moderation is not an option
3) Manage your stress, some repetitive tasks I find useful, like household chores