The American population is aging and living longer. Perhaps pain management via opioids is quicker than sustained, more expensive treatments? The medical explanation leaves too much unexplained. I think that many Americans are turning to opioids (and other things) as a way of dulling the pain of disillusionment.
The late-modern period is a a time of disillusionment in the West and perhaps nowhere else is that disillusionment more acute than in America where, since at the least the early 20th century, the false promises of Modernity (human perfectibility, the universal fatherhood of God, the universal brotherhood of humanity) have proved hollow. The dreams of Modernity died in Europe in the opening months of World War I. In part because that war was not fought on American soil, the Modern dream persisted in the USA. Who can say when it died but it perhaps it was a long, slow death. The Modernists, those who assumed that man is the measure of all things, who assumed a critical stance (in the sense Marx meant “critical,” meaning, “Modern, enlightened, autonomous) toward all extrinsic authorities (God, the church, nature) laid siege to holy Scripture and did much great damage to its reception in the church. Those who continued to receive the historic, ecumenical view of Scripture were put on the defensive and spent about a century defending its truthfulness (infallibility, inerrancy) and authority while the seven sisters of the Protestant mainline (the UMC, ELCA, PCUSA, EPCUSA, ABC, UCC, and the Disciples of Christ) ingested the higher-critical toxins and began to die. The last time I looked each of them was losing about 70,000 members annually.
By the late 60s the disillusionment with and loss of confidence historic Christianity was fairly widespread. The first sexual revolution of the 1920s was followed by a second and more sustained sexual revolution in the 1960s and 70s in which marriage was implicitly re-defined. No fault divorce was adopted leading to a spike in divorce in the mid-late 70s and signalling a loss of confidence in the institution. Roe v Wade was the sacrament of the second sexual revolution, hence the implacable, unreasoning, unyielding, intransigent defense of abortion at any stage, for any reason by its supporters. In the third sexual revolution what was implicit became explicit and the Supreme Court recognized that reality (but in defiance of any genuine legal or historical basis) by announcing that marriage is now to be regarded as disconnected from nature. The minority on the court has predicted the outcome.
Today, unless the proportionally few Americans actually attend church weekly. Years ago George Barna argued that the actual figure is about 10%. More recently, The The Pew Research Center puts the number south of 35% and dropping. Even among “evangelical Protestants,” those with whom religious fervor is most closely associated, only 58% attend services weekly. Consider the state of the second service in the confessionally and (largely) culturally conservative NAPARC world. The anecdotal evidence suggests that the second service is, as they say in boxing, on the ropes.