Affiliates' Research in Medical Journals, Fall 2020

Changes in the way health insurers pay healthcare providers may not only directly affect the insurers’ patients but may change the providers’ behavior in ways that also affect patients covered by other insurers. Using Medicare data from 2013–2017, the researchers tested for such spillovers in the context of a nationwide Medicare bundled payment reform for hip and knee replacements that was implemented in some areas of the country but not in others, via random assignment. The researchers estimated that the payment reform—which targeted traditional Medicare patients—had effects of similar magnitude and direction on the healthcare experience of nontargeted, privately insured Medicare Advantage patients. They found that the payment reform reduced the share of both traditional Medicare and Medicare Advantage patients being discharged to institutional post-acute care. The fact that providers change their treatment of nontargeted patients suggests that effects on these nontargeted patients need to be accounted for in analyses of a policy’s impact or optimal design. Study results may also be biased if the ‘control group’ of patients not targeted by the policy are also indirectly affected.

Contributions of Public Health, Pharmaceuticals, and Other Medical Care to US Life Expectancy Changes, 1990-2015
Buxbaum JD, Chernew ME, Fendrick AM, Cutler DM. Health Affairs 39(9), September 2020, pp. 1546–1556.

Life expectancy in the US increased 3.3 years between 1990 and 2015. To better understand the drivers of this increase, this study used vital statistics data and cause-deletion analysis to identify the conditions most responsible for changing life expectancy and quantified how public health, pharmaceuticals, other (nonpharmaceutical) medical care, and other/unknown factors contributed to the improvement. The researchers found that 12 conditions most responsible for changing life expectancy explained 2.9 years of net improvement (85 percent of the total). Ischemic heart disease was the largest positive contributor to life expectancy, and accidental poisoning or drug overdose was the largest negative contributor. Medications with the largest impacts included antiretroviral therapy for HIV, statins for ischemic heart disease, and surfactant and antenatal steroids for low-birthweight babies. Public health improvements were driven by smoking reduction, and increased adoption of known risk reduction practices such as seatbelt usage, putting infants to sleep on their backs, and traffic safety. Forty-four percent of improved life expectancy was attributable to public health, 35 percent was attributable to pharmaceuticals, 13 percent was attributable to other medical care, and -7 percent was attributable to other/unknown factors. These findings emphasize the crucial role of public health advances, as well as pharmaceutical innovation, in explaining improvements in life expectancy.