BMJ Ment Health. 2026 Sep 2;29(1):e302777. doi: 10.1136/bmjment-2026-302777.
ABSTRACT
BACKGROUND: Somatic and psychiatric illnesses and multimorbidities increase stress-vulnerability and decrease well-being.
OBJECTIVE: We aimed to identify high-risk disorder profiles for lower well-being and well-being decline under stress, modelling COVID-19 as a natural experiment.
METHODS: The global Collaborative Outcomes Study on Health and Functioning during Infection Times survey assessed the World Health Organization-Five Well-being Index (WHO-5) (0-100) retrospectively pre-pandemic and intra-pandemically. Mixed-effects models, controlling for demographic/pandemic-related covariates, examined coprimary outcomes: total pre-pandemic WHO-5 and pre-to-intra-pandemic change (estimating β); pre-pandemic WHO-5 <50, new pre-to-intra-pandemic WHO-5 <50 and WHO-5 decrease ≥10 (estimating ORs±95% CIs). Fixed effects were self-reported somatic and psychiatric diagnoses and within-and-across multimorbidities.
FINDINGS: Altogether, 121 066 adults (female=64.0%, white=69.0%, age=42.0±15.9 years, countries=155) with illnesses (any=49.8%/somatic=44.8%/psychiatric=16.3%) and multimorbidities (any=32.8%/somatic=27.3%/psychiatric=7.4%/somatic-psychiatric=10.8%) were analysed. Well-being was 2-3-fold worse with psychiatric disorders (pre-pandemic: autism-spectrum disorder (β=-7.00±2.93/OR=1.27-2.65), schizophrenia/schizoaffective disorder (β=-5.39±3.42/OR=1.09-2.64); pre-to-intra-pandemic: major depressive disorder (β=-2.45±0.89/OR=1.25-1.55), post-traumatic stress disorder (β=-1.98±1.42/OR=1.19-1.67)) versus somatic disorders (pre-pandemic: diarrhoea (β=-3.29±2.49/OR=1.11-2.15), chronic skin disease (CSD) (β=-2.53±1.44/OR=1.11-1.65); pre-to-intra-pandemic: CSD (β=-2.31±1.47/OR=1.23-1.75), injury (β=-2.22±0.99/OR=1.11-1.40)). Multimorbidities were associated with non-linear/supra-additive adverse outcomes beyond single disorders (pre-pandemic: anorexia nervosa+schizophrenia/schizoaffective disorder (β=-27.58±12.71/OR=1.41-19.94), inflammatory bowel disease+psychosis (β=-24.89±10.59/OR=2.68-24.25), stroke+osteoarthritis (β=-13.68±7.33/OR=1.23-6.48); pre-to-intra-pandemic: haemorrhoids+obsessive-compulsive disorder (β=-8.86±6.54/OR=1.22-5.21), binge-eating disorder/bulimia nervosa+social anxiety disorder (β=-6.87±5.49/OR=0.78-2.85), back pain+retinopathy (β=-6.55±6.54/OR=1.04-4.69)). Dose-response relationships were observed between the number of disorders and poorer well-being (pre-pandemic per diagnosis: psychiatric (β=-1.22±0.23/OR=1.11-1.17), somatic (β=-0.21±0.13/OR=1.02-1.05); pre-to-intra-pandemic per diagnosis: psychiatric (β=-0.37±0.24/OR=1.04-1.10)).
CONCLUSIONS: Poor well-being and further decline under stress were observed particularly with psychiatric illnesses and complex psychiatric and mixed psychiatric-somatic multimorbidity.
CLINICAL IMPLICATIONS: The finding of supra-additive multimorbidity burden highlights a need for targeted care models, beyond individual conditions. Vulnerable groups require support during crises, beyond COVID-19.
PMID:42686352 | DOI:10.1136/bmjment-2026-302777