The new england journal of medicine
n engl j med 370;9 nejm.org february 27, 2014 882
a substantial gradient in alcohol intake accord-
ing to nut consumption could overcome the as-
sumption for a strong unmeasured confounder
in the array-approach sensitivity analysis (Table
S6 in the Supplementary Appendix), which ac-
counted for a maximal difference in prevalence
of 40 percentage points between participants who
ate nuts seven or more times per week and those
who never ate nuts.
Factors such as income level and the pattern
of nut consumption (e.g., socially related con-
sumption) should have been studied and, further-
more, adjusted for in the models.
Eran Kopel, M.D., M.P.H.
Shaye Kivity, M.D.
Yechezkel Sidi, M.D.
Chaim Sheba Medical Center
Tel Hashomer, Israel
eran.kopel@mail.huji.ac.il
No potential conflict of interest relevant to this letter was re-
ported.
1. Stringhini S, Sabia S, Shipley M, et al. Association of socio-
economic position with health behaviors and mortality. JAMA
2010;303:1159-66.
DOI: 10.1056/NEJMc1315777
The authors and a colleague reply: We agree
with Elin that nuts are rich in magnesium, a fact
that may contribute to the observed inverse asso-
ciation between nut consumption and total mor-
tality. We performed an additional analysis ad-
justing for total magnesium intake and found
similar results. Hazard ratios for death among
participants who ate nuts seven or more times
per week, as compared with those who did not
eat nuts, were 0.79 in the cohort of women (95%
confidence interval [CI], 0.69 to 0.91), 0.81 in the
cohort of men (95% CI, 0.73 to 0.90), and 0.80 in
the pooled cohort (95% CI, 0.74 to 0.87).
As suggested by Kopel et al., we performed
an additional analysis adjusting for alcohol intake
as a continuous variable and found similar re-
sults. Hazard ratios for death among participants
who ate nuts seven or more times per week, as
compared with those who did not eat nuts, were
0.78 in the cohort of women (95% CI, 0.68 to
0.90), 0.78 in the cohort of men (95% CI, 0.71 to
0.87), and 0.78 in the pooled cohort (95% CI,
0.72 to 0.85). Although socioeconomic status is
related to mortality, the study participants, being
nurses and health professionals, are relatively
homogeneous.
Ying Bao, M.D., Sc.D.
Bernard A. Rosner, Ph.D.
Brigham and Women’s Hospital
Boston, MA
ying.bao@channing.harvard.edu
Charles S. Fuchs, M.D., M.P.H.
Dana–Farber Cancer Institute
Boston, MA
Dr. Rosner reports no potential conflict of interest relevant to
this letter. Since publication of their article, Drs. Bao and Fuchs
report no further potential conflict of interest.
DOI: 10.1056/NEJMc1315777
Laryngeal Mask Airway in Medical Emergencies
To the Editor: In their Video in Clinical Medi-
cine, Lighthall et al. (Nov. 14 issue)
1
illuminate
the utility of the laryngeal mask airway (LMA) in
airway management during cardiopulmonary ar-
rest. However, the existing data supporting the
emergency application of this and other supra-
glottic airway devices (e.g., the laryngeal tube)
are limited and conflicting. Lighthall et al. state
that LMA placement is usually successful on the
first attempt, but a meta-analysis showed that
the success rate for prehospital LMA insertion
was only 85%.
2
Numerous observational studies
have not shown reliable differences in outcomes
for cardiopulmonary arrest between the use of
supraglottic airway devices and tracheal intuba-
tion, and the use of any advanced airway device
has not been shown to be superior to bag-and-
mask ventilation alone.
3-5
The most effective ap-
proach to airway management probably varies
according to the characteristics of the patients,
the clinical circumstances, and the airway expe-
rience and skills of the rescuer. Prospective, con-
trolled trials would help to clarify the best ap-
proaches to emergency airway management,
particularly during cardiopulmonary arrest.
Henry E. Wang, M.D.
University of Alabama School of Medicine
Birmingham, AL
Clifton W. Callaway, M.D., Ph.D.
University of Pittsburgh School of Medicine
Pittsburgh, PA
Jasmeet Soar, M.B.
Southmead Hospital
Bristol, United Kingdom
jasmeetsoar@icloud.com
The New England Journal of Medicine
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