Bipolar spectrum, hypothyroidism, and their association with chronic fatigue/myalgic encephalomyelitis-like syndrome in long COVID: could they be identified as early determinants? — CFSMEATLAS
Bipolar spectrum, hypothyroidism, and their association with chronic fatigue/myalgic encephalomyelitis-like syndrome in long COVID: could they be identified as early determinants?
Tusconi, Massimo, Dursun, Serdar M, Pegreffi, Francesco et al. · Frontiers in psychiatry · 2025 · DOI
Quick Summary
This study found that people with long COVID who developed ME/CFS-like symptoms were much more likely to have had hypothyroidism (an underactive thyroid) or bipolar spectrum disorders before getting sick compared to people from before the pandemic. The researchers suggest these pre-existing conditions might make someone more vulnerable to developing ME/CFS after COVID-19, possibly because they affect sleep rhythms and immune function.
Why It Matters
Identifying potential risk factors for ME/CFS development in long COVID could enable earlier recognition and intervention for vulnerable populations. Understanding whether thyroid function and mood regulation disorders contribute to ME/CFS susceptibility may inform preventive strategies and personalized treatment approaches for at-risk long COVID patients.
Observed Findings
Hypothyroidism was present in 27.78% of long COVID-CFS/ME patients versus 1.14% in pre-pandemic controls.
Bipolar spectrum disorders were found in 16.67% of cases versus 0.2% in controls.
Depressive symptoms (PHQ-9 score >9) occurred in 55.5% of CFS/ME cases versus 4.16% of controls.
All comparisons showed p<0.0001, indicating highly statistically significant differences.
Odds ratios were substantial: 33.07 for hypothyroidism and 138.4 for bipolar spectrum disorders.
Inferred Conclusions
Hypothyroidism and bipolar spectrum disorders may act as predisposing factors for ME/CFS development in long COVID patients.
These pre-existing conditions may influence biorhythm regulation and immune function in ways that increase vulnerability to persistent ME/CFS after COVID-19.
Early identification of hypothyroidism and bipolar spectrum disorders could facilitate targeted intervention strategies in at-risk long COVID populations.
Remaining Questions
Is the association causal or correlational? Do these conditions directly increase ME/CFS risk, or do they share common underlying mechanisms?
Would early thyroid optimization or psychiatric treatment in at-risk long COVID patients prevent or reduce ME/CFS development?
What This Study Does Not Prove
This study cannot prove that hypothyroidism or bipolar spectrum disorders cause ME/CFS—only that they are more common in people who developed it. The retrospective design and reliance on clinical trial participants (rather than population-based sampling) may not represent all long COVID patients. The significantly smaller case group (n=36) compared to historical controls limits generalizability.
Tags
Symptom:Cognitive DysfunctionFatigue
Phenotype:Long COVID Overlap
Method Flag:PEM Not DefinedWeak Case DefinitionExploratory Only