One possible second order effect: when people's parents are alive longer, they feel happier and more connected to society and are more productive.

There could be many other potential second-order effects (and third-order, etc).

I would think healthier populations improves the economy. The people with the most disposable income are usually the ones who either never had kids or whose kids have all grown up.

More people alive spending money helps the economy.

Increased productive years are, though.