Predictors of Resilience and Vulnerability to Chronic Pain Syndromes and Chronic Fatigue – The Cheshire Oro-facial Pain Prospective Population Study

Problem

Our previously published population based cross-sectional study showed, for the first time, that frequently unexplained chronic pain syndromes including chronic fatigue co-occur in the general population. However, it remains unclear what factors predict persistence of these co-morbid conditions and also factors that predict resilience to the same. Understanding protective factors for resilience and risk factors for vulnerability can help tailor interventions for these common co-morbid conditions.

Approach

We conducted a prospective population based study. A total of 1735 subjects who had completed a baseline questionnaire and had consented to further follow-up were eligible to participate in the follow-up phase. All subjects were randomly selected from a general medical practice in North West England and were assessed at baseline and 24 month follow-up for the presence of chronic widespread pain, chronic orofacial pain, irritable bowel syndrome and chronic fatigue. Subjects completed validated scales assessing levels of anxiety and depression (Hospital Anxiety and Depression Scale), illness behaviour (Illness Behaviour Scale), life stressors (life events inventory), reporting of somatic symptoms (Somatic Symptom Checklist) and sleep disturbance. Logistic regression was used to determine relative risks with 95% confidence intervals for each of these factors in predicting persistence of co-morbid syndromes (vulnerability) and also risks associated with absence of co-mobidities (resilience). Multivariate analyses was used to determine the strongest predictors for resilience and vulnerability whilst taking into account confounding factors (demographic and psychosocial).

Findings

1315 subjects returned completed questionnaires (response rate 84% after adjusting for those who had migrated, deceased, had moved house or were not on the electoral register, n = 177). 232 (21%) had 2 or more syndromes at baselines and follow-up and were defined as vulnerable. 592 (73%) had no symptoms at baseline or follow-up and were defined as resilient. Multivariate analyses using logistic regression showed that the strongest predictors of vulnerability to multiple syndromes were depression (Relative Risk (RR) 8.2, 95% CI 4.0-17.0) and sleep disturbance (RR 3.4, 95% CI 2.0-5.9). Other predictors included being female, having high levels of health anxiety and reporting of somatic symptoms and adverse life events all of which had a 2 fold increased risk.The strongest protective factor for being resilient to multiple syndromes was having low levels of depression (RR 0.1, 95% CI 0.03-0.3). Other protective factors included being male, having low levels of sleep disturbance and health anxiety, fewer adverse life events and somatic symptoms.

Consequences

The findings from this prospective population-based study have identified high levels of depression and sleep disturbance as key predictors for vulnerability to continued persistence of multiple co-morbid pain disorders including chronic fatigue. Low levels of the same factors were protective towards absence of these syndromes. Future interventions targeted towards management of these syndromes need to incorporate components that target both depression and sleep disturbance to determine whether they improve outcomes for patients presenting with these syndromes.