Author | Study design, year | Country | Age in years (mean or range) | Percentage male | Identification of diabetic patients | Predominantly circulating influenza (sub)strains | Study size (n) |
---|---|---|---|---|---|---|---|
Cohort studies | Â | Â | Â | Â | Â | Â | Â |
Hak [29] | Prospective, 1996/1997 and 1997/1998 | US | ≥65, but not reported for diabetic sub-cohort | Not reported for diabetic sub-cohort | ICD-9 codes, database of managed care organizations | A(H3N2) in both seasons | 14,915 in 96/97 |
21,991 in 97/98 | |||||||
Heymann [21] | Retrospective, 2000/2001 | Israel | Vacc., 72.8 ± 0.6 | Vacc., 51.8 | ICD-9 codes, diabetes register of healthcare service | Not reported | 16,383 |
Non-vacc., 73.1 ± 0.5 | Non-vacc., 42.1 | ||||||
Isotani [31] | Retrospective, 1999/2000 | Japan | Not reported | Not reported | Outpatient clinic, unclear | Influenza A | 450 |
Rodriguez-Blanco [32] | Retrospective, 2002–2005 | Spain | Vacc., 75.2 ± 6.5 | Vacc., 39.8 | ICD-9 codes, clinical records | A(H3N2) | 2,650 |
Non-vacc., 73.1 ± 6.9 | Non-vacc., 42.2 | ||||||
Selvais [33] | Prospective, 1995/96 | Belgium | 56.3 ± 15.9 years | 55 | Diabetes clinic, unclear | Not reported | 432 |
Schade [34] | Retrospective, 1995–1997 | US | 65 to 114 years | Not reported | ICD-9 codes, hospital discharge | Not reported | 26,443 in 96/97 |
23,839 in 97/98 | |||||||
Case–control studies |  |  |  |  |  |  | |
Colquhoun [36] | not matched, 1989 and 1993 | UK | ≤19–85 years | Cases, n = 59 | ICD-9 codes, diabetes register | 1989, A(H3N2) | 114 (37 cases, 77 controls) |
Controls, n = 55 | 1993, A(H3N2) and B | ||||||
Gasparini [37] | Matched, 2010/11 | Italy | Not reported for diabetic sub-cohort | Not reported for diabetic sub-cohort | ICD-9 codes, hospital discharge | A(H1N1)pdm, and B | 78 (46 cases, 32 controls) |
Lau2 [35] | Nested, 2000–2008 | Canada | Working-age, 53 | Working age, 52 elderly, 47 | ICD-9/10 codes, administrative database | Not reported | 91,605 |
Elderly, 741 | |||||||
Looijmans [38] | Nested, 1999/2000 | Netherlands | Cases, 68.1 ± 13.7 | Cases, 51.6 controls, 38.3 | ICPC codes, general practitioners | A(H3N2) | 1,753 (192 cases, 1,561 controls) |
Controls, 69.8 ± 12.6 | |||||||
Wang [39] | Nested, 2001–2009 | Taiwan | Vacc., 73.1 ± 5.9 | Vacc, 50.0 | ICD-9 codes, NHRI-database | Not reported | 9,025 (4,571 vacc., 4,454 non-vacc.) |
Non-vacc., 73.2 ± 6.8 | Non-vacc., 49.5 | ||||||
Total population | Â | Â | Â | Â | Â | 170,924 3 |