Increases in inpatient care spending actually slowed in the 1980’s . Pharma/non-durable spending continued a slow climb then. But outpatient care spending doubled in that decade. Moreover, it seems responsible for most of the spending increases since.
That’s my contribution. Who wants to dig deeper?
UPDATE: I fixed some mistakes.
UPDATE #2: Oops. Look like I misunderstood the question. It was not what happened in the 1980’s, but what happened in 1980. In that year, there was a big jump in sending/GDP in the chart Tyler linked to. Since there was no great leap in health care spending that year (look above), it must have something to do with GDP.