J Korean Med Sci.  2017 Mar;32(3):407-414. 10.3346/jkms.2017.32.3.407.

Clinical Features of Influenza and Acute Respiratory Illness in Older Adults at Least 50 Years of Age in an Outpatient Setting in the Republic of Korea: a Prospective, Observational, Cohort Study

• Kim WJ
• Lee JS
• Lee CK
• Cheong HJ
• Kim M
• Monegal JS
• Carneiro R
• Kyaw MH
• Haguinet F
• Ray R
• Matias G

• KMID: 2366635
• DOI: http://doi.org/10.3346/jkms.2017.32.3.407

Abstract

Two prospective, multi-centre, observational studies (GlaxoSmithKline [GSK] identifier No. 110938 and 112519) were performed over 2 influenza seasons (2007-2008 and 2008-2009) in the Republic of Korea (ROK) with the aim to evaluate the burden of laboratory-confirmed influenza (LCI) in patients ≥ 50 years of age seeking medical attention for acute respiratory illness (ARI). The median participant age was 58 years in the 2007-2008 season and 60 years in the 2008-2009 season. LCI was observed in 101/346 (29.2%) of ARI patients in the 2007-2008 season and in 166/443 (37.5%) of ARI patients in the 2008-2009 season. Compared to patients with non-influenza ARI, those with LCI had higher rates of decreased daily activities (60.4% vs. 32.9% in 2007-2008 and 46.4% vs. 25.8% in 2008-2009), work absenteeism (51.1% vs. 25.6% and 14.4% vs. 7.7%), and longer duration of illness. These results indicated that influenza is an important cause of ARI in adults aged 50 and older causing more severe illness than non-influenza related ARI.

Keyword

Acute Respiratory Illness; Adult; Epidemiology; Influenza; Republic of Korea

MeSH Terms

Absenteeism
Adult*
Cohort Studies*
Epidemiology
Humans
Influenza, Human*
Outpatients*
Prospective Studies*
Republic of Korea*
Seasons

Figure

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  Fig. 1 Participants flow diagram. Protocol violations: did not meet the pre-defined diagnostic criteria; Other: patients enrolled outside the influenza season. ARI = acute respiratory illness, ATP = according to protocol, LCI = laboratory-confirmed influenza.

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  Fig. 2 Distribution of influenza type by age group in the 2007–2008 (A) and 2008–2009 (B) seasons.

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