The relation of psychological status and type D personality with central sensitization in knee osteoarthritis: everything is in your mind!

To evaluate the relation of psychosocial parameters and type D personality with central sensitization in knee osteoarthritis (OA). The study included 126 patients with knee OA according to the American College of Rheumatology criteria. Sociodemographic variables (age, gender, education, marital status, annual income), alcohol consumption/smoking, body mass index, comorbidities, and duration of symptoms were noted. Radiographic evaluation was performed according to the Kellgren-Lawrence grading system. The Western Ontario and McMaster Universities Osteoarthritis Index was used for clinical evaluation. Type D personality, negative affectivity, and social inhibition were evaluated using the type D Scale-14 (DS14). Central sensitization was assessed by the central sensitization inventory (CSI), while psychological status, quality of life, and sleep were assessed by the Hospital Anxiety and Depression Scale (HADS), an abbreviated version of the World Health Organization Quality of Life Instrument (WHOQOL-BREF), and the Jenkins Sleep Evaluation Scale (JSS), respectively. The effect of type D personality on study parameters including central sensitization, as well as the risk factors for the development of central sensitization were assessed by regression analyses. Patients with type D personality had higher CSI, HADS scores and lower WHOQOL-BREF scores for psychological health, social relationship, environment and general quality of life. Linear regression analysis showed that the DS14 total score has a significant positive relation with CSI (β = 0.4, p < 0.05), HADS-depression (β = 0.4, p < 0.05), HADS-anxiety (β = 0.5, p < 0.05), and HADS-total scores (β = 0.5, p < 0.05). It also had a significant negative effect on all domains of WHOQOL-BREF (p < 0.05 for all). Logistic regression analysis revealed that JSS [Odds ratio (OR) 0.83, 95% CI 0.73-0.94; p = 0.003] and negative affectivity (OR 0.78, 95% CI 0.65-0.94; p = 0.008) were independent risk factors for the development of central sensitization in knee OA. Type D personality has an impact on quality of life, central sensitization, and psychological health, with negative affectivity and sleep impairment serving as independent risk factors for central sensitization. While managing patients with knee OA, these intimate relationships should be taken into consideration.