Restricted accessResearch articleFirst published online 2025-12
Potential barriers to timely Alzheimer's disease diagnosis and treatment: Tracer delivery and patient travel to amyloid PET scanners in the United States
Several disease-modifying Alzheimer's disease treatments are available or in clinical trials. Participation in these trials and access to approved treatments often require amyloid positron emission tomography (PET) scans. Amyloid PET requires a radioactive tracer with a short half-life so PET scanner must be near a cyclotron facility that produces and delivers viable tracers. We examined the size and composition of the US population that faces likely geographic obstacles due to travel time constraints. Our estimate that 1.5 million older Americans would drive more than one hour to a qualifying PET site raises concern for differences in access to memory care.
MintunMALoACDuggan EvansC, et al.Donanemab in early Alzheimer’s disease. N Engl J Med2021; 384: 1691–1704.
2.
Van DyckCHSwansonCJAisenP, et al.Lecanemab in early Alzheimer’s disease. N Engl J Med2023; 388: 9–21.
3.
CummingsJZhouYLeeG, et al.Alzheimer's disease drug development pipeline: 2024. Alzheimers Dement (N Y)2024; 10: e12465.
4.
BrooksMRabinoviciGDSelkoeDJ, et al. Donanemab: Appropriate use recommendations. J Prev Alzheimers Dis2025; 12: 100150.
5.
RabinoviciGDSelkoeDJSchindlerSE, et al.Donanemab: appropriate use recommendations. J Prev Alzheimers Dis2025; 12: 100150.
6.
BurusTVanHeleneADRooneyMK, et al.Travel-time disparities in access to proton beam therapy for cancer treatment. JAMA Network Open2024; 7: e2410670.
7.
ChapleauMIaccarinoLSoleimani-MeigooniD, et al.The role of amyloid PET in imaging neurodegenerative disorders: a review. J Nucl Med2022; 63: 13s–19s.
8.
LiuJLHlavkaJPHillestadR, et al.Assessing the preparedness of the U.S. health care system infrastructure for an Alzheimer's treatment. Santa Monica, CA: RAND Corporation, 2017.
9.
PattersonJC2ndMosleyML. How available is positron emission tomography in the United States?Mol Imaging Biol2005; 7: 197–200.
10.
LamJJunHChoSK, et al.Projection of budgetary savings to US state Medicaid programs from reduced nursing home use due to an Alzheimer's disease treatment. Alzheimers Dement (Amst)2021; 13: e12159.
AkinlotanMKhodakaramiNPrimmK, et al.Travel for medical or dental care by race/ethnicity and rurality in the U.S.: findings from the 2001, 2009 and 2017 National Household Travel Surveys. Prev Med Rep2023; 35: 102297.
13.
U.S. Department of Transportation. North American roads. Washington, DC: Bureau of Transportation Statistics, 2024.
U.S. Census Bureau. American Community Survey 5-year estimates, 2017–2021. https://data.census.gov/ (2022, Accessed March 11, 2025).
18.
LivingstonGHuntleyJLiuKY, et al.Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. Lancet2024; 404: 572–628.
19.
WolfeMKMcDonaldNCHolmesGM. Transportation barriers to health care in the United States: findings from the National Health Interview Survey, 1997–2017. Am J Public Health2020; 110: 815–822.
20.
JiangCYabroffKRDengL, et al.Self-reported transportation barriers to health care among US cancer survivors. JAMA Oncol2022; 8: 775–778.
21.
MullensCLCollinsRAKunnathN, et al.Trends in travel time to obtain surgical care for rural patients. JAMA2025; 333: 1453–1455.
22.
HungPDengSZahndWE, et al.Geographic disparities in residential proximity to colorectal and cervical cancer care providers. Cancer2020; 126: 1068–1076.
23.
AmbroggiMBiasiniCDel GiovaneC, et al.Distance as a barrier to cancer diagnosis and treatment: review of the literature. Oncologist2015; 20: 1378–1385.
24.
JiangCYabroffKRDengL, et al.Transportation barriers, emergency room use, and mortality risk among US adults by cancer history. J Natl Cancer Inst2023; 115: 815–821.
25.
CouchECoMAlbertynCP, et al.A qualitative study of informal caregiver perceptions of the benefits of an early dementia diagnosis. BMC Health Serv Res2024; 24: 508.
