Risk of hospitalization and death from COVID-19 infection in patients with chronic plaque psoriasis receiving a biologic treatment and renal transplant recipients in maintenance immunosuppressive treatment.

To the Editor: There is uncertainty concerning the outcome of COVID-19 infection in patients receiving systemic therapies such as biologics and immunosuppressive drugs. Whether biologics for psoriasis should be interrupted for preventing severe complications of COVID-19 infection is debated. ,

We performed a retrospective observational study to determine whether patients with chronic plaque psoriasis on biologic or other immunosuppressive therapy and patients who had received a renal transplant had a higher risk of hospitalization or death from COVID-19 infection compared with the general population of Verona during the observation period from February 20 to April 10, 2020. Inclusion criteria for patients with psoriasis and transplant were being regularly monitored at the Division of Dermatology and Nephrology of the Azienda Ospedaliera Universitaria Integrata Verona, respectively, being treated with a biologic or immunosuppressive medication, and being a resident in Verona. Data were obtained by consulting the electronic medical records of the hospital and compared with the Verona population (n = 257,353) (Table I ). The overall study population resides in Verona, so that the reference hospital is the same. Data of Verona residents were derived from the national public database and are expressed as means ± SD or percentages. Statistical analyses for comparison between patients and the general population included the unpaired t test and the χ2 test.

Table I

Study population including patients with psoriasis on biologic therapy, renal transplant recipients, and general population∗

Parameter†	Patients with PsO on biologic therapy (n = 980)	Renal transplant recipients (n = 247)	General population (n = 257,353)	P
Individuals positive for COVID-19	…‡	…‡	3199 (1.2)
Hospitalized for COVID-19–related disease	0	1 (0.4)	589 (0.2)
Died of COVID-19–related disease	0	0	227 (0.08)
Male sex	568 (58)	157 (63.5)	133,823 (52)	<.05
Age, y	56.4 ± 12.4	57.7 ± 13.1	44	<.05
Obesity	294 (30)	25 (10)	25,220 (9.8)	<.05
Cardiovascular disease	137 (12)	164 (66)	20,588 (8)	<.05
Hypertension	333 (34)	200 (81)	48,897 (19)	<.05
Diabetes	117 (12)	32 (13)	9779 (3.8)	<.05
Psoriatic arthritis	303 (31)	-	-
Biologic or immunosuppressive therapy	Anti TNF-α inhibitors: 490 (50)	CNI monotherapy: 18 (7)
	IL-17 inhibitors: 274 (28)	CNI plus antimetabolite: 195 (79)	-
	IL-12/23 inhibitor: 166 (17)	mTORi monotherapy: 4 (1.6)	-
	IL-23 inhibitors: 49 (5)	mTORi + CNI: 12 (4.8)	-
		Antimetabolite monotherapy: 6 (2.4)	-
		Antimetabolite + mTORi: 11 (4.4)	-

CNI, Calcineurin inhibitors; IL, interleukin; mTORi, mammalian target of rapamycin inhibitor; TNF, tumor necrosis factor; PsO, psoriasis.

Data of patients with psoriasis and transplant recipients are derived from the hospital's electronic medical record. Data of the general population are derived from https://www.azero.veneto.it/-/emergenza-coronavirus, https://www.epicentro.iss.it, and http://demo.istat.it, accessed on April 10, 2020.

Data are presented as number (%) or as mean ± SD.

Asymptomatic individuals were not tested, so the true number of patients positive for COVID-19 is unknown.

As of April 10, 2020, 3199 patients (1.2% of population) in Verona were positive for COVID 19 (including those who did not require hospitalization or die). Among 980 patients with chronic plaque psoriasis on biologics, no hospitalization or death was documented. Among 243 patients who had received a renal transplant, 1 required hospitalization for fever and pneumonia but fully recovered. The prevalence of obesity, hypertension, diabetes, and positive history of cardiovascular diseases was higher in patients with psoriasis and those who had received a transplant than the general population. The mean age and prevalence of male sex was higher in patients than in controls.

We acknowledge the limitations of this preliminary study, including the absence of molecular or serologic testing for COVID-19 infection in our study population, because current criteria for performing diagnostic tests for COVID-19 exclude general asymptomatic individuals. The large difference in sample size between patients and the general population and the very low number of hospitalizations and deaths in the patients group do not permit us to draw any inferential statistics. However, the objective of the study was not investigating the prevalence of COVID-19 infection in our patients, but rather reporting the occurrence of the severe outcomes, such as hospitalization and death, related to the COVID-19 infection.

The strength of the study is that we have access to the full medical records of the patients, so that if there had been a case of hospitalization or death from COVID-19, it would have been detected.

Although patients with psoriasis and transplant recipients are older, burdened by metabolic and cardiovascular comorbidities, and above all, immunosuppressed, there is no early signal of an increased hospitalization or death from COVID-19. We acknowledge that patients on biologics or immunosuppressive drugs may have self-isolated more effectively and focused on improved hygiene, thus limiting their own infection risk.