Symptomatic treatment of the cough in whooping cough
Bettiol, S and Wang, K and Thompson, MJ and Roberts, NW and Perera, R and Heneghan, CJ and Harnden, A, Symptomatic treatment of the cough in whooping cough, Cochrane Database of Systematic Reviews, (5) Article CD003257. ISSN 1469-493X (2012) [Refereed Article]
The worldwide incidence of whooping cough (pertussis) has been estimated at 48.5 million cases and nearly 295,000 deaths per year.
In low-income countries, the case-fatality rate among infants may be as high as 4%. Much of the morbidity of whooping cough in
children and adults is due to the effects of the paroxysmal cough. Cough treatments proposed include corticosteroids, beta 2-adrenergic
agonists, pertussis-specific immunoglobulin, antihistamines and possibly leukotriene receptor antagonists (LTRAs).
To assess the effectiveness and safety of interventions to reduce the severity of paroxysmal cough in whooping cough in children and
We updated searches of the Cochrane Central Register of Controlled Trials (CENTRAL Issue 2, 2012), which contains the Cochrane
Acute Respiratory Infections Groupís Specialised Register, theDatabase of Abstracts of Reviews of Effects (DARE Issue 2, 2012) accessed
from The Cochrane Library, MEDLINE (1950 to January 2012), EMBASE (1980 to January 2012), AMED (1985 to January 2012),
CINAHL (1980 to January 2012) and LILACS (January 2012). We searched Current Controlled Trials to identify trials in progress.
We selected randomised controlled trials (RCTs) and quasi-RCTs of any intervention (excluding antibiotics and vaccines) to suppress
the cough in whooping cough.
Data collection and analysis
Two review authors (SB, MT) independently selected trials, extracted data and assessed the quality of each trial for this review in
2009. Two review authors (SB, KW) independently reviewed additional studies identified by the updated search in 2012. The primary
outcome was frequency of paroxysms of coughing. Secondary outcomes were frequency of vomiting, frequency of whoop, frequency
of cyanosis (turning blue), development of serious complications, mortality from any cause, side effects due to medication, admission
to hospital and duration of hospital stay.Main results
Ten trials were included of varying sample sizes (N = 9 to 135) from high-income countries. Study quality was generally poor. Included
studies did not show a statistically significant benefit for any of the interventions. Only six trials including a total of 196 participants
reported data in sufficient detail for analysis. Diphenhydramine did not change coughing episodes; the mean difference (MD) of
coughing spells per 24 hours was 1.9; 95% confidence interval (CI) - 4.7 to 8.5. One study on pertussis immunoglobulin reported
a possible mean reduction of -3.1 whoops per 24 hours (95% CI -6.2 to 0.02) but no change in hospital stay (MD -0.7 days; 95%
CI -3.8 to 2.4). Dexamethasone did not show a clear decrease in length of hospital stay (MD -3.5 days; 95% CI -15.3 to 8.4) and
salbutamol showed no change in coughing paroxysms per 24 hours (MD -0.2; 95% CI -4.1 to 3.7). Only one trial comparing pertussis
immunoglobulin versus placebo reported data on adverse events: 4.3% in the treatment group (rash) versus 5.3% in the placebo group
(loose stools, pain and swelling at injection site).
There is insufficient evidence to draw conclusions about the effectiveness of interventions for the cough in whooping cough.