Background:

An increased risk of cardiovascular diseases (CVD) has been reported among patients with Ankylosing Spondylitis (AS). As of today, little is known what causes this increase.

Objectives: The aim of this study was to evaluate whether traditional CVD risk factors, such as smoking, diet, physical activity and atherogenic blood lipids, differ among AS patients in comparison to the general population.

Methods: Eighty-nine patients diagnosed with AS by fulfilling the modified New York criteria were identified in the databases of a community intervention programme, the Västerbotten Intervention Programme (VIP). The patients were compared with 356 controls matched for age, sex and study period. As part of the VIP, participants have completed questionnaires regarding diet, physical activity and smoking. Additionally, the VIP included measurement of blood pressure, height and weight, and blood samples analysed for cholesterol, serum triglycerides and blood glucose.

Results: Levels of serum triglycerides (p<0.01) and cholesterol (p<0.01) were significantly lower in the patient group. Among the patients, the level of triglycerides was inversely correlated to the intake of total fat (r_s = -0.25, p<0.05), monounsaturated fats (r_s = -0.29, p<0.05) and positively correlated to the intake of carbohydrates (r_s =0.26, p<0.05). These correlations were not seen among the controls. No significant differences were found between patients and controls regarding diet, physical activity, exercise frequency or smoking habits nor in measurements of body mass index (BMI), weight or blood pressure.

Conclusions: The patients exhibited significantly lower levels of cholesterol and triglycerides compared with controls. There were correlations between diet and atherogenic blood lipids among the patients which were not found in the control group. The results suggest that there may be differences in fat metabolism among patients with AS in comparison with the general population.