Care networks designed to improve outcomes and cut overhead costs might be doing neither for elderly patients with complex conditions, according to a new study.

Accountable care organizations’ self-reported management and coordination activities were not associated with improved outcomes or lower spending for elderly patients with multiple diagnoses, according to a Dartmouth Institute for Health Policy & Clinical Practice study published in JAMA Network Open in early July.

There was no significant difference between the ACOs providing the most coordination and those providing the least, researchers said.

They examined records for 1.4 million Medicare beneficiaries who had frailty or multiple chronic conditions and were assigned to various ACOs. Researchers then compared outcomes.

Overall, Medicare beneficiaries who remain in the same accountable care organization over a four-year period have been found to have 10% lower healthcare costs.

But a June report from the Medicare Payment Advisory Commission showed that costs skyrocketed for ACO beneficiaries who had a catastrophic health event.

The Dartmouth researchers said providers should reassess whether approaches used in more general settings work for patients with complex needs.