Gender Differences in Subjective and Objective Measures for Patients with Lumbar Degenerative Disc Disease

Abstract

Background: It has been observed that gender differences exist for the perception of pain. However, the genetic, biochemical, and developmental reasons behind this phenomenon remain unclear. This work aims to elucidate gender differences in subjective and objective measures of pain, functional disability, and health-related quality of life (hrQoL) in patients with lumbar degenerative disc disease (DDD). Methods: In a prospective two-center study, back and leg pain (using the visual analogue scale [VAS]), functional disability scores (Oswestry Disability Index [ODI] and Roland–Morris Disability Index [RMDI]), and hrQoL evaluation (using the EuroQol 5D (Eq. 5D) and Short-Form (SF-12)) were recorded for 253 consecutive patients scheduled for lumbar spine surgery (study group). In addition, objective functional disability was measured using the timed-up-and-go (TUG) test. The same examinations were applied to a healthy cohort of n = 110 subjects (control group). Results: One-hundred thirty-seven patients (46 females) had a microdiscectomy, 80 (42 females) a decompression, and 36 (19 females) a fusion procedure. Female patients were slightly older than male patients (61.0 vs. 56.6 years, p = 0.0306). All other baseline demographic data (body mass index [BMI], smoking status, ASA score, and Charlson comorbidity index [CCI]) were similar in both female and male patients (p > 0.0931). The mean TUG test time was 12.9 seconds in female and 10.1 seconds in male patients (p = 0.0004). Mean VAS back and leg pain was 4.5 and 5.3 in female patients compared with 3.5 and 4.5 in male patients (p = 0.0021 and 0.0246). The ODI was higher in female patients (51.2 vs. 46.3, p = 0.0042) and, correspondingly, the SF-12 PCS lower in female patients (28.8 vs. 31.3, p = 0.0060). All other subjective preoperative measures (RMDI, Eq. 5D, VAS and Eq. 5D Index, and SF-12 MCS) did not differ between female and male patients. In the healthy control group, female subjects took a mean of 1.1 seconds longer than males (6.5 vs. 5.4 seconds, p < 0.0001). There was no difference in the subjective measures between female and male controls subjects. Conclusions: We found significant gender differences in subjective and objective measures of pain intensity, functional disability, and hrQoL in patients with lumbar DDD. Female patients reported higher pain, higher disability, and more reduced hrQoL as compared with male patients. Correspondingly, the TUG test was significantly longer in female patients/controls.