The possible link between hypertension and osteoarthritis

Abstract

Background: The prevalence of hypertension and osteoarthritis increase with age and are frequent comorbidities. Both share another thing in common; hypertension is a vascular disease while the final pathogenesis of osteoarthritis is vascular. Hypertension is associated with a higher likelihood of vascular end-organ event (cerebral, cardiac, microvascular and renal outcomes). Osteoarthritis final pathway is a perfusion abnormality of the synovium, articular cartilage and subchondral bone. That presupposes another end organ vascular event.

Objective: To assess the prevalence of hypertension and osteoarthritis in patients attending an orthopaedic clinic, evaluate and explore commonality and possible aetiological linkages. Null hypothesis: Hypertension has no link with large joint osteoarthritis.

Methods: A retrospective review of 788 case files of patients seen in an orthopaedic clinic between January 2019 and March 2020. Five hundred and sixteen patient files had complete data and were selected for the study. The raw data were entered on a data sheet. The patient’s age, gender, weight, height, and BMI were all extracted and recorded. The Mean Arterial Blood Pressure (MAP) (calculated from the average BP value) was the main independent variable. The average BP value was taken by averaging at least three BP readings taken on different visits. The dependent variable was osteoarthritis of any major joint. Osteoarthritis was diagnosed radiologically. For statistical analysis, the study carried out the frequencies, means, Pearson correlation, odds ratio and multivariate linear regression.

Results: The overall prevalence of hypertension in the sample was 36%. Similarly, the prevalence of osteoarthritis was 17%, but much higher in the hypertensive cohort (25%, P <0.001). The mean systolic and diastolic blood pressures increased with age in men and women, although 36% of the hypertensives were below 40 years. Osteoarthritis showed to be a strong risk factor (OR = 2.2). Other risk factors included male gender (OR =1.7), and diabetes mellitus (OR = 1.7), and overweight (OR = 2.7). Stepwise logistic regression revealed large joint osteoarthritis to be a moderate predictor of hypertension (R = 0.4, P< 0.001).

Conclusion: The study reveals the risk factors of increasing age, overweight, diabetes, and osteoarthritis as significant correlates and risk factors for hypertension in the orthopaedic patient cohort. All patients attending orthopaedic outpatient clinics should have their BP taken. BP measurements should be mandatory in the elderly particularly those with osteoarthritis. Orthopaedic surgeons should have some knowledge on how to manage uncomplicated hypertension. Null hypothesis: Large joint osteoarthritis has no link with hypertension.