[Is breast-feeding a protective factor for infectious diseases? A case-control study].
OBJECTIVE
To analyze if breast-feeding (BF) is a protective factor against infectious diseases.


METHODS
Case-control study. Retrospective study during 1998.


METHODS
Primary care. Teaching health center. Population of 22,500 inhabitants.


METHODS
We consider an alpha risk of .05 and a beta risk of .20, unilateral hypothesis. We estimated a sample of 48 children in the "case" group and 144 in the "control" group. Random sample.


METHODS
Cases were children with 3 or more acute respiratory or digestive infectious episodes during the first year of age. Controls were children with less than 3 episodes. We analyze exposure to breast feeding (BF) and we consider it if the child had at least 3 months of BF. In other case we define as a non-exposure child. We have calculated odds ratio (OR) and its 95% confidence intervals.


RESULTS
60.4% of the children were BF after birth. But only 28.5% lasted 3 months, and only 13.9% lasted 1 year. The median of BF was 3.3 months (SD 4.2). 79.2% of the children have a respiratory infectious disease in the first year and 14.6% diarrhea. In children less than 1 year old the OR was 0.81 (95% CI, 0.40-1.63). In the period 3-6 months old we have found an OR of 0.346 (95% CI 0.161-0.744).


CONCLUSIONS
In children aged less than 1 year, we have not found protective effects of breast-feeding against acute respiratory infectious diseases. Only in the period 3-6 months old, we have found that BF protects against these diseases.
Carratalá Munuera
M C
MC
Departamento de Medicina Clínica, Universidad Miguel Hernández, Campus de San Juan, Elche, Alicante, Spain.
Gascón Pérez
E
E
Raga Ortega
M
M
D000367:Age Factors; D001942:Breast Feeding; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012141:Respiratory Tract Infections / Q000517:prevention & control*
Public Health Nutr. 2001 Dec;4(6A):1347-51
11918478
Breastfeed Rev. 2002 Nov;10(3):5-18
12592775
BMJ. 2001 Dec 8;323(7325):1358-62
11739226
Cochrane Database Syst Rev. 2002;(1):CD003517
11869667
Aten Primaria. 2002 Feb 15;29(2):79-83
11844423
JAMA. 2001 Jan 24-31;285(4):413-20
11242425
Aten Primaria. 1997 Apr 15;19(6):318-22
9264672
J Nutr. 2001 Feb;131(2):262-7
11160544
Am J Epidemiol. 1996 Jun 1;143(11):1142-8
8633604
Pediatrics. 2002 Dec;110(6):1103-9
12456906
Aten Primaria. 2002 Mar 31;29(5):268-77
11996726
An Esp Pediatr. 1999 Apr;50(4):333-40
10356823
Aten Primaria. 1999 Oct 15;24(6):337-43
10596224
Aten Primaria. 1996 Sep 15;18(4):164-7
8962995
Public Health Nutr. 2001 Apr;4(2B):631-45
11683556
BMJ. 1999 May 15;318(7194):1316-20
10323815
Aten Primaria. 1996 Sep 30;18(5):253-6
8963015
Arch Dis Child. 2003 Mar;88(3):224-8
12598384