Impact of a selective narrow network with comprehensive patient navigation on access, utilization, expenditures, and enrollee experiences

Objective To examine the effect of enrollee switching from a broad-network accountable care organization (ACO) health maintenance organization (HMO) to a "high performance" ACO-HMO with a selective narrow network and comprehensive patient navigation system on access, utilization, expenditures, and enrollee experiences. Data Sources Secondary administrative data were obtained for 2016-2020, and primary interview and survey data in 2021. Study Design Fixed-effects instrumental variable analyses of administrative data and regression analyses of survey data. Outcomes included access, utilization, expenditures, and enrollee experience. Background information was gathered via interviews. Data Collection/Extraction Methods We obtained medical expenditure/enrollment and access data on continuously enrolled members in a broad-network ACO-HMO (n = 24,555), a subset of those who switched to a high-performance ACO-HMO in 2018 (n = 7664); interviews of organizational leaders (n = 13); and an enrollee survey (n = 512). Principal Findings Health care effectiveness data and information Set (HEDIS) access measures were not different across plans. However, annual utilization dropped by 15.5 percentage points (95% CI: 18.1, 12.9) more in the high-performance ACO-HMO, with relative annual expenditures declining by $1251 (95% CI: $1461, $1042) per person per year. High-performance ACO-HMO enrollees were 10.1 percentage points (95% CI 0.001, 0.201) more likely to access primary care usually or always as soon as needed and 11.2 percentage points (95% CI 0.007, 0.217) more likely to access specialty care usually or always as soon as needed. Plan satisfaction was 7.1 percentage points (95% CI: -0.001, 0.138) higher in the high-performance ACO-HMO. Interviewees noted the comprehensive patient navigation system was designed to ensure patients remained in the narrow network to receive care. Conclusions ACO and HMO contracts with selective narrow networks supported by comprehensive patient navigation can reduce expenditures and improve specialty access and patient satisfaction compared to broad-network plans that lack these features. Payers should consider implementing narrow networks with comprehensive support systems.