DEVELOPMENT of giant cell arteritis (GCA) was associated with higher levels of apolipoprotein A-I (ApoA-I) at baseline, according to new research.
“Previous work from our group indicated that obesity and diabetes were associated with a reduced risk for GCA, and that there was also an inverse relation with total cholesterol,” explained study author Carl Turesson, Lund University, Sweden. To investigate the potential association between GCA and ApoA-I, Turesson and colleagues conducted a nested case-control study, using patient data from the Malmö Diet Cancer Study (n=30,447; mean age: 58 years; 60.2% female).
A total of 100 patients from the study developed GCA (81% female; mean age at diagnosis: 73.6 years), and were matched to four control individuals randomly selected from the cohort. Concentrations of ApoA-I and apolipoprotein B in stored serum were collected at baseline, and potential predictors of GCA were examined in conditional logistic regression models.
Results showed that patients who later developed GCA had significantly higher ApoA-I levels at baseline compared to controls, with a mean level of 168.7 mg/dL versus 160.9 mg/dL (odds ratio [OR]: 1.57; 95% confidence interval [CI]: 1.18–2.10). Apolipoprotein B levels were similar between cases and controls, with a mean level of 109.3 versus 110.4 mg/dL (OR: 0.99; 95% CI: 0.74–1.32). The association between ApoA-I and GCA development remained significant in analysis adjusted for BMI and physical activity (OR: 1.48; 95% CI: 1.09–1.99).
Limitations of the study included the fact that apolipoprotein levels were only measured at one point in time. Furthermore, the number of male patients in the study was limited, and the team noted that results should be interpreted with caution.
The researchers concluded that subsequent development of GCA was associated with significantly higher ApoA-I levels at baseline. Taken together with previous observations on lower BMI and fasting glucose levels in individuals who develop GCA, the study findings suggest that a healthier metabolic profile, associated with lower risk of cardiovascular disease, may predispose to GCA.
