New Study Contradicts Previous Findings on Psoriatic Arthritis, Cardiovascular Comorbidity

A new matched cohort analysis contradicts several prior studies that conclude patients with psoriatic arthritis face an increased risk of cardiovascular comorbidity.

Investigators matched 4 otherwise similar to people to all patients diagnosed with psoriatic arthritis, psoriasis or ankylosing spondylitis at a British primary care practice between 1999 and 2009. They then used Fisher’s exact test to compare cardiovascular outcomes between the matched patients and the 106 psoriatic arthritis patients, 290 psoriasis patients and 94 ankylosing spondylitis patients.

Psoriatic arthritis patients did suffer significantly higher rates of hypertension than their matched cohorts: 41 psoriatic arthritis patients (38.7 %) vs. 114 matched patients (26.9 %); p = 0.02. The only other significant finding was an elevated risk of hypertension among ankylosing spondylitis patients: 35 ankylosing spondylitis patients (37.2 %) vs. 96 matched patients (25.5 %); p = 0.03.

Psoriasis patients did not experience significantly elevated rates of hypertension, and none of the study patients experienced significantly elevated rates of ischemic heart disease, hyperlipidemia or diabetes mellitus.

“Our findings provide UK comparisons of cardiovascular disease-related comorbidities in patients with ankylosing spondylitis, psoriatic arthritis and psoriasis alone; specifically, demonstrating increased prevalence of hypertension in ankylosing spondylitis and psoriatic arthritis cohorts compared to their matched cohorts,” the study authors wrote in Clinical Rheumatology. “This further supports the argument for more evidence in the need for screening and intervention around cardiovascular disease comorbidities in inflammatory conditions.”

Some prior research does support the conclusions of the new study.

For example, a 2011 paper compared cardiovascular comorbidities in 611 psoriatic arthritis patients and 449 psoriasis-only patients. Univariate analysis found that psoriatic arthritis patients had significantly higher rates of hypertension, obesity, hyperlipidemia, type 2 diabetes mellitus, and at least 1 cardiovascular event. (The odds ratio [OR] for these conditions ranged from 1.54 to 2.59.) However — when investigators adjusted for age, sex, education, smoking status, severity and duration of psoriasis, medication status, and other comorbidities — the only comorbidity that remained significantly elevated was hypertension (adjusted OR, 2.17).

The split between the adjusted and unadjusted findings led the study authors to an ambiguous conclusion.

“The results suggest that inflammatory joint disease may play a role in both cardiovascular and non-cardiovascular morbidity in psoriatic arthritis,” they wrote.

A number of other studies have reached somewhat ambiguous conclusions, but the balance of evidence indicates a link between psoriatic arthritis and cardiovascular co-morbidity and disease, according to a 2011 research review that appeared in Annals of the Rheumatic Diseases.

“Most studies point towards an increased cardiovascular risk in psoriatic arthritis, broadly on a par with the risk level in rheumatoid arthritis, emphasizing the need for similar cardiovascular risk management in both conditions,” wrote the review’s authors, who had gathered and analyzed 28 previous articles.

“Studies on all-cause mortality revealed mixed results. Available data on cardiovascular disease appeared more consistent, indicating an increased cardiovascular mortality and morbidity in psoriatic arthritis. Commensurate with this, surrogate markers of subclinical atherosclerosis, arterial stiffness and cardiovascular risk factors, for example hypertension, dyslipidemia, obesity and metabolic-related factors, were more prominent in psoriatic arthritis compared with controls.”

The new study appears just weeks after a paper in the International Journal of Angiology, which found evidence that psoriatic arthritis is independently linked to cardiovascular disease.