Contrast media: anaphylaxis risk was increased with beta-blockers or asthma.

Clinical bottom line (level 3b)

  1. Patients on beta-blockers or with asthma were at an increased risk of anaphylaxis during contrast media studies (NNH = 290 at unknown) and (NNH = 170 at unknown) , respectively.
Lang et al: Annals of Internal Medicine 1991; 115 (4): 270-276
Expires February 2003

The study

Case-control study with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: university hospital, USA

189 patients (aged ?, ?% male) having intravenous contrast media studies
Cases: 63 patients (% male, mean age ): adverse reactions
Controls: 126 patients (% male, mean age ): no adverse reactions


Outcomes studied:
  • anaphylaxis - occurrence within 20 minutes of infusion of one or more of: urticaria, angioedema, throat constriction or stridor, bronchospasm, hypotension (systolic drop 30 mmHg or more), syncope, cardiac dysrhythmia or arrest associated with urticaria or angioedema

    • Cases and controls were similar in antihistamine and corticosteroid use.

    The evidence

    Patient expected event rate for anaphylaxis: 0.17%
    risk factor anaphylaxis
    present    		 anaphylaxis
    absent    		 unadjusted OR
    (95% CI)    		 NNH
    (95% CI)
    beta-blocker or asthma 19 13 3.43
    (1.45 to 8.15)     		250
    (84 to 1300)
    no beta-blocker or asthma 30 68

    risk factor anaphylaxis
    present    		 anaphylaxis
    absent    		 unadjusted OR
    (95% CI)    		 NNH
    (95% CI)
    beta-blocker 13 10 3.07
    (1.15 to 8.21)     		290
    (83 to 4000)
    no beta-blocker 36 71

    risk factor anaphylaxis
    present    		 anaphylaxis
    absent    		 unadjusted OR
    (95% CI)    		 NNH
    (95% CI)
    asthma 5 3 4.54
    (1.03 to 20.1)     		170
    (32 to 20000)
    no asthma 44 78

    • 69% of anaphylactoid reactions were severe, and 10% of patients were admitted.

    Citation

    1. Lang DM, Alpern MB, Visintainer PF, et al: Increased risk for anaphylactoid reaction from contrast media in patients on beta-adrenergic blockers or with asthma. Annals of Internal Medicine 1991; 115 (4): 270-276
    Contributor: Chris Ball and Clare Wotton, June 2000
    Reviewer: Richard Koopmans

    Clinical Question.
    Patient having iv contrast media studies
    Intervention or Exposure beta-blocker or asthma
    Outcome adverse reactions