The influence of personality traits on perception of pain in older adults - Findings from the Swedish National Study on Aging and Care - Blekinge study.

Background and aims The experience of pain may vary in accordance with personality traits and individual characteristics. Neuroticism is demonstrated to constitute a vulnerability factor among younger and middle-aged pain patients. The combination of openness and neuroticism is associated with high anxiety/depression scores among adult individuals with chronic conditions. The aim of this study was to investigate possible associations between pain and the personality dimensions of neuroticism, extroversion, openness, agreeableness and conscientiousness among persons aged 60 years and older. An additional aim was to explore whether such associations are equally gender expressed. Methods The Swedish National Study on Aging and Care includes a randomly selected sample from the National Population Register. The data collection was conducted at four research centres and was approved by the Ethics Committees of Lund University and the Karolinska Institutet, Stockholm, Sweden. The Blekinge sample includes 1402 individuals, aged 60-96 years, of whom 769 (55%) reported pain. A total of 2312 individuals had been invited to participate. The reason for non-participation was registered. Participants underwent medical examination and testing by research personnel, conducted in two sessions, each of which lasted about 3 h. A questionnaire was completed between the two sessions. Pain was self-reported and based on the question: Have you had ache/pain during the last 4 weeks? Information on personality traits was obtained by means of the personality SGC1 questionnaire; a 60-item Swedish version of Costa & McCrae's FFM questionnaire. Personality traits were then tested based on gender by means of multivariate forward logistic regression in models adjusted for age, insomnia, financial status and educational level. Results When adjusting for covariates among women, neuroticism had a small but significant odds ratio of experiencing pain (OR 1.05, CI 1.02-1.08). Insomnia had the highest odds ratio (OR 2.19, CI 1.52-3.15) followed by low education (OR 1.59, CI 1.07-2.36), while belonging to the younger part of the older adult cohort was also associated with pain (OR 1.02, CI 1.005-1.04). In men, neuroticism (OR 1.03, CI 1.002-1.06) followed by openness (OR 1.03 CI 1.001-1.07) had a small but significant odds ratio of experiencing pain. Insomnia had the highest odds ratio (OR 1.98, CI 1.24-3.15). Conclusions Personality traits and pain were related among the older adults but there were gender differences. The relationship between pain and neuroticism in women was about the same in strength as the relation between pain and neuroticism/openness in men. Both sexes suffer from insomnia. The relationship between personality traits and pain was only affected to a minor extent by insomnia. Implications There is a need to increase awareness of the impact of personality as well as to provide improved treatment for pain and insomnia in older people.