According to the National Council of State Legislatures, as of June this year Republicans controlled 61% of state legislatures and Democrats 35%. In terms of whole state governments, Republicans controlled 46% and Democrats 12%, with 12 states divided.
The study authors also noted that American life expectancy as a whole is lower than in most high-income countries, “fall[ing] between … Cuba and Albania”.
They wrote: “The rise in working-age mortality rates in the US in recent decades largely reflects stalled declines in cardiovascular disease mortality alongside rising mortality from alcohol-induced causes, suicide and drug poisoning; and it has been especially severe in some US states. Building on recent work, this study examined whether US state policy contexts may be a central explanation.”