Volume 18, Number 2—February 2012
Declining Guillain-Barré Syndrome after Campylobacteriosis Control, New Zealand, 1988–2010
|Initial hospitalization condition||ICD-9 codes||ICD-10 codes||Denominator population†||Subsequent GBS hospitalizations (concurrent hospitalizations)‡||Crude rate§||Age-standardized rate¶ (95% CI)||Age-standardized rate ratio (95% CI)|
|Infectious diseases (ICD chapter 1)||001–139||A00–B99||732,254||56 (273)||90.7||87.0 (56.9–116.4)||34.3 (29.2–40.3)|
|Pneumonia and influenza||480–488||J09–J18||250,399||19 (82)||91.1||96.2 (25.1–167.3)||37.9 (26.5–54.3)|
|Enteric diseases#||001–002 004–008.42 008.44–009.3||A00–A01 A03–A04.4 A04.6–A09||77,793||6 (21)||93.3||132.0 (1.2–262.7)||52.0 (32.2–84.2|
|Campylobacteriosis||008.43||A04.5||8,448||5 (29)||710.2||810.0 (41.4–1,578.7)||319.4 (201.5–506.4)|
|New Zealand population GBS rate||NA||NA||53,617,400||1,320||2.5||2.5 (2.4–2.7)||Referent|
*GBS, Guillain-Barré syndrome; ICD, International Classification of Diseases; ICD-9, ICD 9th Revision; ICD-10, ICD 10th Revision; NA, not applicable.
†Denominator population based on either 1) incident hospitalizations for specific condition (number of acute and arranged first overnight hospitalizations as principal or additional diagnosis); or 2) total New Zealand population person-years for July 1995– December 2008 for calculating the New Zealand population GBS rate.
‡First hospitalization of GBS either 1) among those with a previous hospitalization in the preceding 30 d and excluding those with concurrent diagnoses (numbers in parentheses); or 2) in the total New Zealand population for July 1995–December 2008.
§Rate per 100,000 person-years at risk. For GBS hospitalizations after specific conditions, monthly rate has been multiplied by 12 to convert to annual rate.
¶Standard population is population of New Zealand according to the New Zealand 2006 Census of Population and Dwellings (www.stats.govt.nz/Census/2006CensusHomePage/classification-counts-tables/about-people/age.aspx).
#Excluding campylobacteriosis and salmonellosis.