The rise in health care prices at a faster rate than inflation started in 1968, coincidentally with the arrival of Medicare/Medicaid (an attempt to reduce costs).
After 1980 US really took off though. In 1980 US spend 8.2% of GDP, Germany 8.1%, Denmark 8.4%
By 1990 US was 11.2%, Germany and Denmark 8%
US plataued in 1993 about 12%, lasting until 2000 when it took off again, reaching 16% in 2009, then was mostly flat (slightly reducing) until 2013.
Also 1986 was the emergency room mandate, which used Medicare payments as leverage. And of course the obesity epidemic and the low-fat diet (blaming fat for heart disease) started around then. The ACA started in 2010 but phased in over four years.