Risk of Cervical Dizziness in Patients With Cervical Spondylosis

Importance The dizziness associated with cervical spondylosis is a controversial topic given that many experts believe that cervical spondylosis is a common cause of dizziness, whereas others do not believe it exists. Objective To compare the risk of dizziness between patients with cervical spondylosis and matched controls (ie, patients with lumbar spondylosis after propensity score matching [PSM]). Design, Setting, and Participants This cohort study used medical claims data from the National Health Insurance Research Database of Taiwan for patients 60 years or older with cervical or lumbar spondylosis newly diagnosed in any outpatient department between January 1, 2010, and December 31, 2015. Patients diagnosed with cervical spondylosis were included as the study cohort, and those diagnosed with lumbar spondylosis who were matched to the study cohort via PSM were selected as the control cohort. Both cohorts were followed up for 1 year unless they were diagnosed with dizziness, censored by death, or withdrew from the health insurance program. Data analysis was performed from August 9 to September 20, 2022. Main Outcomes and Measures The main outcome was the date of outpatient diagnosis of dizziness. The risks of dizziness were compared between groups. The relative risk and incidence rate difference were calculated. Results A total of 3638 patients with cervical spondylosis (mean [SD] age, 67.9 [7.1] years; 2024 [55.6%] male) and 3638 patients with lumbar spondylosis (mean [SD] age, 68.0 [7.1] years; 2024 [55.6%] male) after PSM were selected as the study and control cohorts, respectively. The patients with cervical spondylosis had higher risk of dizziness than matched controls, with a 1-year relative risk of 1.20 (95% CI, 1.03-1.39). The 1-year incidence of dizziness was 10.2% (95% CI, 9.2%-11.2%) in patients with cervical spondylosis and 8.6% (95% CI, 7.7%-9.5%) in the matched group of lumbar spondylosis. The incidence rate difference between the groups was 1.6% (95% CI, 0.3%-3.0%). Conclusions and Relevance These data support the association between dizziness and cervical spondylosis, but the small difference between groups reveals that dizziness associated with cervical spondylosis is uncommon. Clinicians should be wary of diagnosing a cervical cause for dizziness based on an actual history of cervical spondylosis.