Does smoking status affect baseline symptom severity and patient-reported outcomes and satisfaction in patients with cervical myelopathy at 24 months? A Quality Outcomes Database study.

Abstract

It is not clear whether smoking impacts patient-reported outcomes (PROs) in patients with cervical spondylotic myelopathy (CSM). The aim of this study was to explore the impact of smoking status on baseline symptom severity and the rate of achieving satisfaction and the minimal clinically important differences (MCIDs) for PROs in patients with CSM. This study was an analysis of the prospective Quality Outcomes Database CSM module. Patients aged ≥ 18 years diagnosed with primary CSM who underwent elective surgery were included. PROs (visual analog scale [VAS] neck and arm pain, Neck Disability Index [NDI], modified Japanese Orthopaedic Association [mJOA], and EQ-5D scores and North American Spine Society [NASS] patient satisfaction) were collected at baseline and 24 months of follow-up. Of the 1141 patients with CSM, 202 (17.7%) were smokers and 939 (82.3%) were nonsmokers. Compared with the nonsmokers, smokers were younger (56.3 ± 11.3 years vs 61.5 ± 11.7 years, p < 0.01) and had a lower BMI (29.3 ± 6.8 vs 30.3 ± 6.3, p = 0.04). A higher proportion of smokers had depression, anxiety, and chronic obstructive pulmonary disease (all p < 0.01). At baseline, smokers had worse pain (VAS neck pain score: 6.0 ± 3.2 vs 5.1 ± 3.3; VAS arm pain score: 5.7 ± 3.2 vs 4.7 ± 3.5), disability (NDI score: 45.2 ± 20.0 vs 37.1 ± 20.6), myelopathy (mJOA score: 11.5 ± 2.9 vs 12.2 ± 2.8), and quality of life (EQ-5D score: 0.51 ± 0.23 vs 0.57 ± 0.22) (all p < 0.01). At the 24-month follow-up, a higher proportion of smokers achieved the MCID in mJOA (69.4% vs 56.6%, p < 0.01) compared with nonsmokers. However, after accounting for significant covariates, there was no significant difference in the baseline disease severity. There was also no difference between the PROs at the 24-month follow-up. The two groups also achieved similar MCIDs for most PROs and were similarly satisfied (NASS score of 1 or 2: smoker 81.2% vs nonsmoker 84.6%, p = 0.29) 24 months after surgery. Smokers and nonsmokers with CSM had similar baseline disease severity and 24-month PROs. They also achieved similar rates of MCIDs for PROs and satisfaction after surgery. Numerous previous studies have documented the association between tobacco usage and inferior clinical outcomes after spine surgery. However, in the context of severe and debilitating spinal disorders such as cervical myelopathy, meaningful and impactful improvements are still seen in properly selected patients.