Widespread Multimorbidity in a Cohort of Aging, Radiation-exposed Rhesus Macaques

Area of Science:

• Radiation biology
• Primate models
• Chronic disease research

Background:

• Delayed effects of acute radiation exposure (DEARE) manifest years after irradiation.
• Chronic diseases like cardiac issues and bone loss are common in aging populations.
• Radiation exposure may exacerbate age-related disease risks.

Purpose of the Study:

• To characterize chronic disease incidence, onset age, and multimorbidity in irradiated rhesus macaques.
• To identify excess chronic disease risk attributable to radiation-induced tissue damage.
• To investigate the impact of radiation on lifespan and disease progression over time.

Main Methods:

• Studied 226 irradiated and 51 control rhesus macaques from the Radiation Late Effects Cohort (RLEC).
• Assessed incidence and age of onset for 20 common chronic diseases.
• Analyzed lifespan, multimorbidity, and potential dose-response relationships.

Main Results:

• Irradiated macaques had a significantly shorter lifespan (average 5.1 years less).
• Radiation exposure accelerated the onset of periodontitis, cataracts, bone loss, overweight conditions, and arthritis.
• Irradiated animals exhibited higher rates of periodontitis, cataracts, testicular atrophy, tumors, diabetes, and brain lesions, with increased multimorbidity.

Conclusions:

• Radiation exposure significantly increases chronic disease burden and accelerates onset in rhesus macaques.
• Specific disease clusters related to fibrosis and bone loss were observed.
• No clear dose-effect relationship was found, suggesting individual resilience factors influence radiation response.