The pain characteristics of respondents with LBP are reported in Table 3. Frequency of pain was highly associated with its severity; for example, only 17.59% of patients with mild pain reported daily pain compared with 37.94% of those with moderate pain and 63.21% of those with severe pain (P,0.05). Prescription medication use was uncommon overall (only 20% of all LBP respondents used a prescription treatment), whether in isolation or in combination with an over-the-counter treatment), though rates of use increased significantly by severity (from 10.05% to 40.71% in patients with mild to severe pain, respectively) (P,0.05). Opioid use was extremely uncommon but also increased by level of severity (0.40% to 2.86%) (P,0.05).
Prior to covariate adjustment, levels of health status for respondents with LBP were significantly worse than for matched no LBP controls and decreased concomitantly with increasing severity (Table 4). Similarly, levels of work impairment, activity impairment, and health care provider visits were also significantly higher than in matched controls and increased along with severity (all P,0.05). No significant differences were observed in terms of the number of ER visits or hospitalizations in the past 6 months.