Rheumatoid arthritis and the incidence of influenza and influenza-related complications: a retrospective cohort study

Abstract

BackgroundPatients with rheumatoid arthritis (RA) are known to be at increased risk of infection, particularly if they are taking drugs with immunomodulatory effects. There is a need for more information on the risk of influenza in patients with RA.MethodsA retrospective cohort study was carried out using data gathered from a large US commercial health insurance database (Thomson Reuters Medstat MarketScan) from 1 January 2000 to 31 December 2007. Patients were ≥18 years of age, with at least two RA claims diagnoses. The database was scanned for incidence of seasonal influenza and its complications on or up to 30 days after an influenza diagnosis in RA patients and matched controls. Other factors accounted for included medical conditions, use of disease-modifying anti-rheumatic drugs (DMARDs), use of biological agents, influenza vaccination and high- or low-dose corticosteroids. Incidence rate ratios (IRRs) were calculated for influenza and its complications in patients with RA.Results46,030 patients with RA and a matching number of controls had a median age of 57 years. The incidence of influenza was higher in RA patients than in controls (409.33 vs 306.12 cases per 100,000 patient-years), and there was a 2.75-fold increase in incidence of complications in RA. Presence or absence of DMARDs or biologics had no significant effect. The adjusted IRR of influenza was statistically significant in patients aged 60–69 years, and especially among men. A significantly increased rate of influenza complications was observed in women and in both genders combined (but not in men only) when all age groups were combined. In general, the risk of influenza complications was similar in RA patients not receiving DMARDs or biologics to that in all RA patients. Pneumonia rates were significantly higher in women with RA. Rates of stroke/myocardial infarction (MI) were higher in men, although statistical significance was borderline.ConclusionsRA is associated with increased incidence of seasonal influenza and its complications. Gender- and age-specific subgroup data indicate that women generally have a greater rate of complications than men, but that men primarily have an increased rate of stroke and MI complications. Concomitant DMARD or biological use appears not to significantly affect the rate of influenza or its complications.

Infecciones en pacientes reumatológicos asociadas a corticosteroides y antagonistas del factor de necrosis tumoral α

“…En términos globales, los pacientes con AR tienen mayor incidencia de influenza y de complicaciones por influenza respecto a controles pero este riesgo no está asociado al uso de fármacos modificantes o corticosteroides 21 . El uso de corticosteroides como antipirético aumentó el riesgo de muerte, falla respiratoria, shock, falla multiorgánica o ingreso a UCI en pacientes que consultaron por influenza pandémica A H1N1 22 .…”

Vaccination in Rheumatology: Current Aspects

“…Частота случаев инфекции, вызванной вирусом гриппа, при РА значимо превышала таковую в контроле: относительный риск (ОР) 1,22; 95% доверительный интервал (ДИ) 1,05-1,41. При этом осложнения, обусловленные указан-ной инфекцией, среди больных РА развивались в 2,75 раза чаще, чем в контроле, и встречались преимущественно у мужчин в возрасте старше 70 лет [22].…”

Vaccination recommendations for adult patients with rheumatic diseases

“…complications of influenza were increased 2.75 folds in patients with rheumatoid arthritis than in those without the condition (11), and this risk has been reported to be independent of the drug used. The influenza vaccine has been shown to reduce the severity of the disease or attack rate regardless of the treatment given (12).…”