Age-Related Changes in the Clinical Picture of Long COVID

Background: This study evaluated the impact of aging on the frequency and prevalent symptoms of Long COVID, also termed post-acute sequelae of SARS-CoV-2, using a previously developed Long COVID research index (LCRI) of 41 self-reported symptoms in which those with 12 or more points were classified as likely to have Long COVID. Methods: We analyzed community-dwelling participants ≥ 60 years old (2662 with prior infection, 461 controls) compared to participants 18–59 years (7549 infected, 728 controls) in the Researching COVID to Enhance Recovery adult (RECOVER-Adult) cohort ≥ 135 days post-onset. Results: Compared to the Age 18–39 group, the adjusted odds of LCRI ≥ 12 were higher for the Age 40–49 group (odds ratio [OR] = 1.40, 95% confidence intervals [CI] = 1.21–1.61, p < 0.001) and 50–59 group (OR = 1.31, CI = 1.14–1.51, p < 0.001), similar for the Age 60–69 group (OR = 1.09, CI = 0.93–1.27, p = 0.299), and lower for the ≥ 70 group (OR = 0.68, CI = 0.54–0.85, p < 0.001). Participants ≥ 70 years had smaller adjusted differences between infected and uninfected symptom prevalence rates than those aged 18–39 for the following symptoms: hearing loss, fatigue, pain (including joint, back, chest pain and headache), post-exertional malaise, sleep disturbance, hair loss, palpitations, and sexual desire/capacity, making these symptoms less discriminating for Long COVID in older adults than in younger. Symptom clustering, as described in Thaweethai et al. (JAMA 2023) also exhibited age-related shifts: clusters 1 (anosmia and ageusia) and 2 (gastrointestinal, chronic cough and palpitations, without anosmia, ageusia or brain fog) were more likely, and clusters 3 (brain fog, but no loss of smell or taste) and 4 (a mix of symptoms) less likely to be found in older adults (relative risk ratios for clusters 3–4 ranging from 0.10–0.34, p < 0.001 vs. 18–39 year-olds). Conclusions: Within the limits of this observational study, we conclude that in community-dwelling older adults, aging alters the prevalence and pattern of reported Long COVID.