The need to improve detection and treatment of physical pain of homeless people with schizophrenia and bipolar disorders. Results from the French Housing First Study.

Objective: The aim of this study was to investigate the prevalence and associated factors of physical pain in a large multicenter sample of Homeless Schizophrenia and Bipolar (HSB) patients.

Methods: This multicenter study was conducted in 4 French cities: Lille, Marseille, Paris and Toulouse. Pain was measured by EQ5D-3 L questionnaire with no specified period or location. In addition, sociodemographic information, duration of homelessness, illness severity using the Modified Colorado Symptom Index (MCSI) and drug information were collected.

Results: Overall, 655 HSB patients, mean age 38.8 years and 82.6% men were included, 448 (68.9%) were diagnosed with schizophrenia and 202 (31.1%) with bipolar disorder. More than half patients (N = 337, 51.5%) reported moderate to extreme physical pain while only 2.7% were administered analgesic drugs. In the multivariate analysis, self-reported moderate to extreme physical pain was associated with antidepressant consumption (adjusted odd ratio aOR = 2.56[1.25;5.26], p = .01), female gender (aOR = 1.72[1.03;2.86], p = .04), bipolar disorders (vs. schizophrenia) (aOR = 1.81[1.19;2.77], p = .006), older age (aOR = 1.03 [1.01;1.05], p = .01), with higher MCSI psychotic score (a0R = 1.04[1.01;1.06],p = .002), independently of the number of days in the street during the last 180 days, MCSI depression score, alcohol and substance use disorders, psychotropic drugs and analgesic treatments. No association with education level, antipsychotics, mood stabilizers, anxiolytic, hypnotic or medication adherence was found (all p > .05).

Conclusion: Physical pain was highly reported in homeless patients with severe mental illness with insufficient care. Physical pain should be systematically explored and treated in this population. Bipolar disorders, antidepressant consumption and female gender may be targeted in priority. Age and psychotic symptomatology were found to influence self-reported pain in a marginal way.