Health-related quality of life of Malaysian patients with chronic non-malignant pain and its associated factors: a cross-sectional study.

Background: Chronic pain has a major impact on a patient's quality of life, affecting physical and psychological functioning. It has debilitating consequences on social and economic aspects too. This study aimed to explore the status of health-related quality of life (HRQoL) of Malaysian patients suffering from chronic non-malignant pain.

Methods: Four hospitals offering pain clinic services were involved in this multicentre cross-sectional study conducted between June and September 2020. Adult patients who had been diagnosed with non-malignant chronic pain lasting for at least three months and able to communicate in English or Malay language were recruited in this study. Participants were informed about the study and were made aware that their participation was entirely voluntary. A battery of questionnaires consists of the EuroQol-5 dimensions-5 levels questionnaire (EQ-5D-5L) and the EuroQol visual analogue scale (EQ VAS), the Pain Self-Efficacy questionnaire (PSEQ) and the Pain Catastrophizing Scale (PCS) were self-administered by the patients. Besides, a structured questionnaire was used to collect their socio-demographic information, pain condition, sleep quality and working status. Participants' usage of pain medications was quantified using the Quantitative Analgesic Questionnaire (QAQ).

Results: A total of 255 patients participated in this study. A median EQ-5D index value of 0.669 (IQR: 0.475, 0.799) and a median EQ VAS score of 60.0 (IQR: 50.0, 80.0) were recorded. Malay ethnicity (Adj. B: 0.77; 95% CI: 0.029, 0.126; p = 0.002) and a higher level of self-efficacy (Adj. B: 0.008; 95% CI: 0.006, 0.011; p < 0.001) were predictors of a better HRQoL, while suffering from pain in the back and lower limb region (Adj. B: -0.089; 95% CI: - 0.142, - 0.036; p = 0.001), the use of a larger amount of pain medications (Adj. B: -0.013; 95% CI: - 0.019, - 0.006; p < 0.001), and a higher degree of pain magnification (Adj. B: -0.015; 95% CI: - 0.023, - 0.008; p < 0.001) were associated with a poorer HRQoL.

Conclusions: These findings suggested that Malay ethnicity and a higher level of self-efficacy were predictors of a better HRQoL in patients with chronic pain, whereas pain-related factors such as higher usage of medication, specific pain site and pain magnification style were predictors of poorer HRQoL.