Objective

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.

Method

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.

Results

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.

Conclusion

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.

Background

Traumatic events are common globally; however, comprehensive population-based cross-national data on the epidemiology of posttraumatic stress disorder (PTSD), the paradigmatic trauma-related mental disorder, are lacking.

Methods

Data were analyzed from 26 population surveys in the World Health Organization World Mental Health Surveys. A total of 71 083 respondents ages 18+ participated. The Composite International Diagnostic Interview assessed exposure to traumatic events as well as 30-day, 12-month, and lifetime PTSD. Respondents were also assessed for treatment in the 12 months preceding the survey. Age of onset distributions were examined by country income level. Associations of PTSD were examined with country income, world region, and respondent demographics.

Results

The cross-national lifetime prevalence of PTSD was 3.9% in the total sample and 5.6% among the trauma exposed. Half of respondents with PTSD reported persistent symptoms. Treatment seeking in high-income countries (53.5%) was roughly double that in low-lower middle income (22.8%) and upper-middle income (28.7%) countries. Social disadvantage, including younger age, female sex, being unmarried, being less educated, having lower household income, and being unemployed, was associated with increased risk of lifetime PTSD among the trauma exposed.

Conclusions

PTSD is prevalent cross-nationally, with half of all global cases being persistent. Only half of those with severe PTSD report receiving any treatment and only a minority receive specialty mental health care. Striking disparities in PTSD treatment exist by country income level. Increasing access to effective treatment, especially in low- and middle-income countries, remains critical for reducing the population burden of PTSD.