An Alzheimer's drug may ease fatigue and depression in ~63% of long COVID patients with a reactivated herpesvirus

Key Findings

⌚ Long COVID is linked to measurably worse heart and fitness metrics — nearly 2 years later

• Among 1,475 participants a median of 21 months after SARS-CoV-2 infection, 34% (498 people) had high long COVID symptom burden.

• Compared to low-symptom participants, the high-symptom group had lower heart rate variability (-4.4 ms), higher resting heart rate (+1.5 beats/min), ~1,624 fewer steps per day, and 96 fewer metabolic equivalent minutes per week — all measured by wearable sensors over 6 months.

• Two subgroups with abnormal cardiovascular patterns were also linked to lower quality of life scores.

🧬 Cellular 'aging' signals appear early in people who go on to develop long COVID

• Senescence-associated genes (genes linked to a state where cells stop dividing but release inflammatory signals) were significantly more active in early post-infection blood samples from 56 people who later developed long COVID, compared to 104 who did not (normalized enrichment score = 6.04, p = 0.001).

• The same pattern held for 32 people who developed long-term cognitive impairment vs. 40 who did not (NES = 2.58, p = 0.032), and for 26 with persistent breathlessness vs. 53 without (NES = 6.29, p = 0.001).

• One gene, ETS2, was elevated across all long COVID symptom types, while other senescence-linked genes varied by symptom profile.

🧠 Inflammation markers and vitamin D levels are linked to cognitive decline in long COVID

• In a 2-year study of 108 long COVID patients (54 per group, matched by age, sex, and neurological history), elevated neutrophil-to-lymphocyte ratio (NLR — a blood marker of inflammation) was a significant predictor of cognitive decline in both groups: OR = 1.586 in those starting with normal cognition, OR = 5.944 in those already cognitively impaired.

• Severe initial COVID-19 illness (OR = 2.211) and autoimmune conditions (OR = 1.676–4.987) were also independently linked to cognitive worsening.

• Vitamin D levels were significantly associated with cognitive scores in both groups.

📊 Long COVID symptom 'clusters' shift dramatically depending on which algorithm you use

• Researchers applied three different machine learning clustering methods to symptom data from 6,031 long COVID patients (each reporting presence or absence of 162 symptoms) — and got substantially different patient groupings from each method.

• All three methods consistently identified one high-symptom group with more severe post-exertional malaise (worsening of symptoms after activity), but the specific cluster boundaries differed across approaches.

• The overall symptom landscape appeared largely continuous — meaning there may not be truly distinct 'types' of long COVID, but rather a spectrum of severity.

🩸 A blood clotting marker (D-dimer) is linked to symptom severity — and stays elevated months later

• Among 197 long COVID patients (mean age 37.3), 25.4% had elevated D-dimer and 21.8% had elevated fibrinogen (both are markers of clotting activity) at baseline.

• Patients with elevated D-dimer had a 3x higher relative risk of severe symptoms; elevated fibrinogen was linked to a 2.34x higher risk.

• At 3-month follow-up among the 63 patients with abnormal baseline markers, D-dimer remained elevated in 50.8% and fibrinogen in 47.6%.

🫁 A simple breathing device improved breathlessness and function in long COVID patients

• In a controlled trial of 85 long COVID patients in Taiwan, 6 weeks of daily incentive spirometer training (a handheld device that guides deep breathing) significantly improved breathlessness scores across all four experimental groups — including patients 9–12 months post-infection.

• The waiting control group (no device) showed no significant change in dyspnea (p = 0.463) or functional status (p = 0.343).

• Patients who started training within 3 months of recovery showed the largest improvements, but gains were seen even in the latest-recovery group.