Commentary

Arthritis and psychiatric disorders: Disentangling the relationship

The purpose of this study is to determine the impact of total knee arthroplasty (TKA) on mental health.

A total of 205 patients who underwent primary TKA with baseline and 1-year postoperative Short Form-12 Mental Component Score (MCS) were included in this retrospective analysis. Eighty-five (41%) patients had a preoperative MCS less than 50 points, while 120 (59%) patients had a preoperative MCS over 50 points. Two groups were assigned to the patients based on their preoperative MCS: low MCS <50 and high MCS >50.

A preoperative MCS less than 50 points was predictive of greater improvement in MCS at 1 year after TKA (P < .001). Patients with low MCS improved by a mean of 10.6 points from 39.1 ± 8.6 points preoperatively to mean of 49.7 ± 10.7 points 1 year after TKA (P < .001). Patients with a high MCS decreased by a mean of 3.5 points from 60.01 ± 6.0 points preoperatively to mean of 56.6 ± 6.8 points 1 year after TKA (P < .001). This remained higher than the postoperative MCS of the patients with a low MCS, 49.7 ± 10.7 (P < .001). The patients with a high MCS had greater improvement in the Short Form-12-Physical domain (14.8 points) than the patients with a low MCS (9.2 points, P < .001).

Patients with lower baseline mental health had greater improvement in postoperative mental health following TKA than patients with higher baseline mental health. Low preoperative MCS was associated with less improvement in patient-reported outcome measures. Patients with lower baseline mental health scores before TKA benefit mentally and physically from the procedure.

We investigated the associations between DSM-IV mental disorders and subsequent arthritis onset, with and without mental disorder comorbidity adjustment. We aimed to determine whether specific types of mental disorders and increasing numbers of mental disorders were associated with the onset of arthritis later in life.

Data were collected using face-to-face household surveys, conducted in 19 countries from different regions of the world (n = 52,095). Lifetime prevalence and age at onset of 16 DSM-IV mental disorders were assessed retrospectively with the World Health Organization (WHO) Composite International Diagnostic Interview (WHO-CIDI). Arthritis was assessed by self-report of lifetime history of arthritis and age at onset. Survival analyses estimated the association of initial onset of mental disorders with subsequent onset of arthritis.

After adjusting for comorbidity, the number of mood, anxiety, impulse-control, and substance disorders remained significantly associated with arthritis onset showing odds ratios (ORs) ranging from 1.2 to 1.4. Additionally, the risk of developing arthritis increased as the number of mental disorders increased from one to five or more disorders.

This study suggests links between mental disorders and subsequent arthritis onset using a large, multi-country dataset. These associations lend support to the idea that it may be possible to reduce the severity of mental disorder–arthritis comorbidity through early identification and effective treatment of mental disorders.

To examine the relationships between physical, psychological, and social factors and health-related quality of life (HRQOL) and disability in rheumatoid arthritis (RA).

A sample of 106 patients with rheumatoid arthritis (RA) completed measures of self-reported disease activity and psychosocial functioning, including coping, personal mastery, social network, perceived stress, illness beliefs, the SF-36 and Health Assessment Questionnaire Disability Index (HAQ-DI). In addition, physician-based assessment of disease activity using the Disease Activity Scale (DAS-28) was obtained. Hierarchical multiple regression analyses were used to evaluate the relationships between psychosocial factors and scores on the SF-36 and HAQ-DI.

Lower self-reported disease activity was associated with higher SF-36 physical functioning scores, while the contribution of active coping, passive coping, and helplessness was significant only as a block. Lower self-reported disease activity, higher personal mastery, and lower perceived stress contributed to higher SF-36 mental health functioning, and higher self-reported disease activity and lower helplessness were associated with greater disability, as indexed by the HAQ-DI. The DAS-28, an objective of measure of disease activity, was unrelated to any of these outcomes.

The findings highlight the importance of targeting psychological factors to enhance HRQOL and disability in the clinical management of RA patients.