Inflammation is associated with incident hypertension in patients with axial spondyloarthritis: A longitudinal cohort study

KEY MESSAGES What is already known about this subject? center dot Patients with axial spondyloarthritis (axSpA) have a higher risk of cardiovascular (CV) disease compared with the general population. Hypertension (HT) is one of the most important modifiable risk factors. Whether increased inflammatory pathways or the use of anti-inflammatory therapies contribute toward the increased prevalence of HT in axSpA remained controversial. What does this study add? center dot First, higher inflammatory burden as reflected by a longer baseline disease duration, delay in diagnosis and higher ESR levels were predictors of incident HT (IHT) after adjusting for traditional CV risk factors in axSpA. Second, IHTrisk was significantly increased in pati\ents with disease duration >5 years. How might this impact on clinical practice or future developments? center dot Early diagnosis and adequate control of systematic inflammation may be important to prevent the development of HT. Routine screening for hypertension in axSpA patients should be considered, especially in patients with longer disease duration. Objectives To elucidate the risk factors for the development of incident hypertension (IHT) in patients with axial spondyloarthritis (axSpA). Methods We conducted a retrospective cohort study in axSpA patients who were recruited from 2001 to 2019 from a university clinic in Hong Kong. Patients with HT and/or anti-hypertensive drug use at baseline were excluded. They were followed until the end of 2020. The outcome was IHT, defined by a diagnosis and a prescription for an antihypertensive drug. Baseline and time-varying Cox regression analyses adjusting for age, sex, and body mass index (BMI), were used to assess the relationship between drug use, inflammatory burden, and IHT. Results Four hundred and thirteen patients [age: 34(25-43) years, male: 319 (77.2%)] were recruited. After a median follow-up of 12 (6-17) years, 58 patients (14%) developed IHT (IHT+group). Among all the baseline variables, disease duration and delay in diagnosis were the independent predictors for IHT based on the Cox regression model. In the multivariate Cox regression analysis, baseline disease duration, delay in diagnosis and time-varying ESR levels were independent predictors associated with an increased risk of IHT. IHT risk was significantly increased in patients with disease duration >5 years. The use of anti-inflammatory drugs was not associated with the development of IHT. Conclusion Higher inflammatory burden as reflected by a longer disease duration, delay diagnosis and higher ESR levels, were predictors associated with IHT after adjusting for traditional CV risk factors. These data support routine screening for hypertension in axSpA patients, especially those with longer disease duration.