Which factors can aid clinicians to identify a risk of pain during the following month in patients with bone metastases? A longitudinal analyses

PurposeExplore clinical factors associated with higher pain intensity and future pain in patients with bone metastases to identify patients who can benefit from closer follow-up or pain-modifying interventions.MethodsThis is a secondary analysis of 606 patients with bone metastases included in a multicenter longitudinal study. The dependent variables were average pain and worst pain in the last 24h (0-10 NRS). Twenty independent variables with potential association to pain intensity were selected based on previous literature. Cross-sectional analyses were performed with multiple linear regression to explore factors associated with pain intensity at baseline. Longitudinal data were analyzed with a generalized equation models to explore current factors associated with pain intensity at the next visit in 1month.ResultsCurrent pain intensity (p<0.001), sleep disturbances (p 0.01 and 0.006), drowsiness (p 0.003 and 0.033) and male gender (p 0.045 and 0.001) were associated with higher average and worst pain intensity in 1month. In addition, breakthrough pain was related to higher worst pain intensity (p 0.003) in 1month. The same variables were also associated with higher average pain intensity at baseline.ConclusionHigher current pain intensity, sleep disturbances, drowsiness, male gender, and breakthrough pain are factors associated with higher pain intensity in patients with bone metastases at the next follow-up in 1month. These factors should be assessed in clinical practice and may aid clinicians in identifying patients that can benefit from closer follow-up or interventions to prevent lack of future pain control.Trial registration in clinicaltrials.govNCT01362816.