Does healthcare affect the number of deaths, or are lifespans predetermined and not influenced by it?

Allah’s way with His creation is to link effects to their causes. He is capable of creating effects without their causes, but His sunnah (definition) (established way) has been to create the former through the latter, and to bring them into existence through these for a wisdom He knows. Allah has clarified that taking a life is contingent upon its cause, and that the deceased dies at their appointed time, not before it or without a cause. Therefore, healthcare has an effective role in the health of bodies and in combating diseases, but this is by Allah’s permission and decree, for effects are bound to their causes by divine decree and destiny.