Anti-TNF-α therapy improves insulin sensitivity in non-diabetic patients with psoriasis: a 6-month prospective study

Objective: Psoriasis is a chronic inflammatory disease associated with increased risk of cardiovascular death. Several studies have shown a beneficial effect of anti-TNF-α therapy on the mechanisms associated with accelerated atherogenesis in patients with inflammatory arthritis, including an improvement of insulin sensitivity. In this study, we aimed to determine for the first time whether the anti-TNF-α monoclonal antibody adalimumab may improve insulin sensitivity in non-diabetic patients with psoriasis.

Methods: Prospective study on a series of consecutive non-diabetic patients with moderate to severe psoriasis seen at the Dermatology Division of Hospital Universitario Marques de Valdecilla (Northern Spain) who completed 6 months of therapy with adalimumab (80 mg at week 0 followed by 40 mg every other week, starting 1 week after the initial dose). Patients with chronic kidney disease, hypertension or body mass index ≥ 35 kg/m(2) were excluded. Metabolic and clinical evaluation including assessment of insulin sensitivity using the Quantitative Insulin Sensitivity Check Index (QUICKI) was performed at the onset of the treatment (time 0) and at month 6.

Results: Twenty-nine patients (52% women; 38.6 ± 10.7 years) with moderate to severe psoriasis [body surface area (BSA) 37.9 ± 16.3%], Psoriasis Area and Severity Index [(PASI) 18.9 ± 7.8] were assessed. Statistically significant improvement (P=0.008) of insulin sensitivity was observed after 6 months of adalimumab therapy (QUICKI at time 0: 0.35 ± 0.04 vs. 0.37 ± 0.04 at month 6). Significant improvement of erythrocyte sedimentation rate, ultrasensitive C-reactive protein, BSA, PASI, Nail Psoriasis Severity Index, physician global assessment and psoriatic arthritis screening and evaluation questionnaire was also observed at month 6 (P < 0.05 for each variable).

Conclusion: Our results support a beneficial effect of the anti-TNF-α blockade on the mechanisms associated with accelerated atherogenesis in patients with psoriasis.