Intended for healthcare professionals

Rapid response to:

Papers

Randomised trial of telephone intervention in chronic heart failure: DIAL trial

BMJ 2005; 331 doi: https://doi.org/10.1136/bmj.38516.398067.E0 (Published 18 August 2005) Cite this as: BMJ 2005;331:425

Rapid Response:

Re: Close the clinics and cancel home visits in heart failure management? What do the results of the DIAL Trial really tell us?

DIAL trial results: Strength of evidence in heart failure programmes.

Grancelli Hugo, Nul Daniel, Varini Sergio, Soifer Saul, Ferrante Daniel,
Hernán Doval, for GESICA Investigators.
GESICA Foundation, Buenos Aires, Argentina.

The evidence of the effect of heart failure programs comes from
metanalysis of small studies, so the benefit of these interventions might
not be conclusive, since the majority of the studies were from single
centers, with short follow-up, methodological limitations, and low
standardization of interventions. In McAlister`s metanalysis (1), a study
of only 20 patients is included, and in Whellan`s metanalysis (2), 15 of
the 19 studies were from single centers.

DIAL trial should not be considered an addition to previous evidence. It
is a study including 51 centers, 1518 patients, optimal current therapy,
homogeneous telephone intervention (based on education, monitoring and
self-care skills) as the single strategy, with blinded evaluation of end
points by and independent event committee.

The conclusion that telephone interventions are clearly inferior to
multidisciplinary interventions might be misleading. The classification of
the studies in different mataanalysis is rather arbitrary, since the same
study can be found in different categories, for example Krumholz et al
study is classified as telephonic by Whellam and Phillips (3), and non-
telephonic by McAlister.

Moreover, it might not be valid to assume superiority of one strategy,
using results from different studies, where patients and clinical settings
are so different – ambulatory care vs. post discharge, optimal vs. non-
optimal drug therapy, etc.

The effect estimated in Clark’s et al letter is not in agreement with our
reported results, since they did not use time to event analysis.
Well designed large scale clinical trials provide the kind of evidence
that is not obtained with metaanalysis of small studies, since these
reviews are prone to methodological problems and publications biases of
original studies.

The only way to determine if one intervention is superior to another one
would be to design and conduct a large scale randomized clinical trial,
even larger than DIAL trial, comparing different strategies or their
combination.

1- McAlister FA, Stewart S, Ferrua S, McMurray JJ. Multidisciplinary
strategies for the management of heart failure patients at high risk for
admission: a systematic review of randomized trials. J Am Coll Cardiol.
2004 ;44(4):810-9.

2- Whellan DJ, Hasselblad V, Peterson E, O'Connor CM, Schulman KA.
Metaanalysis and review of heart failure disease management randomized
controlled clinical trials. Am Heart J. 2005;149(4):722-9

3- Phillips CO, Wright SM, Kern DE, Singa RM, Shepperd S, Rubin HR.
Comprehensive discharge planning with postdischarge support for older
patients with congestive heart failure: a meta-analysis. JAMA. 2004 Mar
17;291(11):1358-67.

Competing interests:
None declared

Competing interests: No competing interests

19 October 2005
Hugo O Grancelli
Investigator
Daniel Nul, Sergio Varini, Saul Soifer, Daniel Ferrante, Hernán C. Doval, for GESICA Investigators.
Rivadavia 2358 (1034) Buenos Aires ARgentina