Objectives

To evaluate disease activity in the joints and skin during pregnancy and the first year postpartum in patients with psoriatic arthritis (PsA).

Methods

Women with PsA who were pregnant between 1990 and 2015 with at least one clinic visit during pregnancy were identified from the Toronto PsA database. The course of joint and skin disease activity was defined by 5 states: improvement, worsening, stable low, stable high or a mixed. As controls, 67 non-pregnant PsA women were identified and evaluated over a similar timeframe.

Results

29 PsA women with 42 pregnancies were identified. Of the 42 pregnancies 40 (95%) resulted in normal live birth. Arthritis improved or was stable low activity in 24 (58.5%) of pregnancies. During the postpartum period, 21 (52.5%) had either improvement or stable low PsA activity, while 16 (40%) had either worsening or stable high disease activity. The skin activity during pregnancy either improved or stayed in a stable low state in 30 (88.2%), and in the postpartum period there was worsening in 15 (42.9%). A logistic regression analysis revealed a favourable skin disease course during the pregnancy period in the pregnant group compared to the control group (OR 6.8, p=0.004), but not in joint disease.

Conclusions

The outcome of pregnancy among patients with PsA is excellent. Arthritis activity trends toward a favourable course while the skin disease shows a favorable course during pregnancy. When compared to controls, pregnancy period has significant beneficial influence only on the skin but not on the joints in PsA.