Age and co-morbidities as independent risk factors of infections leading to hospital admission in the last year of life among the elderly: A retrospective registry-based study
Abstract
Background: The immune system declines with age, but the impact of chronological age may be affected by sex, co-morbidities, and sociodemographic factors.
Objective: The article aims to study infections associated with hospital admission in the elderly in their last year of life and the impact of age, sex, co-morbidities, and sociodemographic factors.
Method: A retrospective study based on registry data covering all care visits in Stockholm Region, Sweden, for 7 years was conducted. All deceased subjects with at least one hospital admission with infection as the main diagnosis in the last year of life were compared with subjects with no such admission. Subjects were categorized into three different age-groups 65–79, 80–89, and 90 years and above. Co-morbidity was measured by the Charlson Comorbidity Index (CCI) and sociodemographic factors were assessed using the ‘Mosaic-system’. Subjects living in nursing homes were analyzed separately. Uni- and multivariable logistic regressions were conducted.
Results: Of the 55,238 subjects in the study population, 14,192 (26%) had at least one hospital admission due to infection in the last year of life. The risk of having a severe infection increased with age, adjusted odds ratio (OR): 1.30 (1.25–1.36), and 1.60 (1.52–1.69) for the age-groups 80–89 and ≥ 90 compared to the age-group 65–79. The most important factor for infection was a high co-morbidity score; adjusted OR: 1.75 (1.68–1.82). Male sex and living in a less affluent area were weaker risk factors for infections.
Conclusion: Chronological age and co-morbidities are independent risk factors of infections associated with hospital admission in the last year in life while male sex and sociodemographic factors have less impact.
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References
2. Kawasuji H, Morinaga Y, Tani H, Saga Y, Kaneda M, Murai Y, et al. Age-dependent reduction in neutralization against alpha and beta variants of BNT162b2 SARS-CoV-2 vaccine-induced immunity. Microbiol Spectr. 2021;9(3):e0056121. doi: 10.1128/Spectrum.00561-21
3. Macias AE, McElhaney JE, Chaves SS, Nealon J, Nunes MC, Samson SI, et al. The disease burden of influenza beyond respiratory illness. Vaccine. 2021;39 Suppl 1:A6–14. doi: 10.1016/j.vaccine.2020.09.048
4. Falk Erhag H, Guethnadottir G, Alfredsson J, Cederholm T, Ekerstad N, Religa D, et al. The association between the clinical frailty scale and adverse health outcomes in older adults in acute clinical settings – a systematic review of the literature. Clin Interv Aging. 2023;18:249–61. doi: 10.2147/CIA.S388160
5. Rohrmann S. Epidemiology of frailty in older people. Adv Exp Med Biol. 2020;1216:21–7. doi: 10.1007/978-3-030-33330-0_3
6. Strang P, Hedman C, Adlitzer H, Schultz T. Dying from cancer with COVID-19: age, sex, socio-economic status, and comorbidities. Acta Oncol. 2021;60(8):1019–24. doi: 10.1080/0284186X.2021.1934536
7. Strang P, Schultz T. Dying with cancer and COVID-19, with special reference to lung cancer: frailty as a risk factor. Cancers (Basel). 2022;14(23). doi: 10.3390/cancers14236002
8. Grasselli G, Greco M, Zanella A, Albano G, Antonelli M, Bellani G, et al. Risk factors associated with mortality among patients with COVID-19 in intensive care units in Lombardy, Italy. JAMA Intern Med. 2020;180(10):1345–55. doi: 10.1001/jamainternmed.2020.3539
9. Dias SP, Brouwer MC, van de Beek D. Sex and gender differences in bacterial infections. Infect Immun. 2022;90(10):e0028322. doi: 10.1128/iai.00283-22
10. Jacobsen H, Klein SL. Sex differences in immunity to viral infections. Front Immunol. 2021;12:720952. doi: 10.3389/fimmu.2021.720952
11. Klein SL, Flanagan KL. Sex differences in immune responses. Nat Rev Immunol. 2016;16(10):626–38. doi: 10.1038/nri.2016.90
12. Charlson ME, Carrozzino D, Guidi J, Patierno C. Charlson comorbidity index: a critical review of clinimetric properties. Psychother Psychosom. 2022;91(1):8–35. doi: 10.1159/000521288
13. Church S, Rogers E, Rockwood K, Theou O. A scoping review of the Clinical Frailty Scale. BMC Geriatr. 2020;20(1):393. doi: 10.1186/s12877-020-01801-7
14. Gilbert T, Neuburger J, Kraindler J, Keeble E, Smith P, Ariti C, et al. Development and validation of a Hospital Frailty Risk Score focusing on older people in acute care settings using electronic hospital records: an observational study. Lancet. 2018;391(10132):1775–82. doi: 10.1016/S0140-6736(18)30668-8
15. Dahlen E, Komen J, Jonsson EW, Almqvist C, Kull I, Wettermark B. Eliminated patient fee and changes in dispensing patterns of asthma medication in children – an interrupted time series analysis. Basic Clin Pharmacol Toxicol. 2019;125(4):360–9. doi: 10.1111/bcpt.13268
16. Strang P, Furst P, Schultz T. Excess deaths from COVID-19 correlate with age and socio-economic status. A database study in the Stockholm region. Ups J Med Sci. 2020;125(4):297–304. doi: 10.1080/03009734.2020.1828513
17. Humbert M, Olofsson A, Wullimann D, Niessl J, Hodcroft EB, Cai C, et al. Functional SARS-CoV-2 cross-reactive CD4(+) T cells established in early childhood decline with age. Proc Natl Acad Sci U S A. 2023;120(12):e2220320120. doi: 10.1073/pnas.2220320120
18. Tuty Kuswardhani RA, Henrina J, Pranata R, Anthonius Lim M, Lawrensia S, Suastika K. Charlson comorbidity index and a composite of poor outcomes in COVID-19 patients: a systematic review and meta-analysis. Diabetes Metab Syndr. 2020;14(6):2103–9. doi: 10.1016/j.dsx.2020.10.022
19. Salaj D, Schultz T, Strang P. Nursing home residents with dementia at end of life: emergency department visits, hospitalizations, and acute hospital deaths. J Palliat Med. 2023. doi: 10.1089/jpm.2023.0201
20. Socialstyrelsen: Nationella principer för prioritering inom intensivvård under extraordinära förhållanden (Swe: National Principles for Prioritization in Intensive Care Units under Extraordinary Conditions). National Board of Health and Welfare (Socialstyrelsen); 2020. Available from: https://www.socialstyrelsen.se/globalassets/sharepoint-dokument/artikelkatalog/foreskrifter-och-allmanna-rad/2014-5-19.pdf [cited March 2024]
21. Elsamadicy AA, Havlik JL, Reeves B, Sherman J, Koo AB, Pennington Z, et al. Assessment of frailty indices and Charlson Comorbidity Index for predicting adverse outcomes in patients undergoing surgery for spine metastases: a national database analysis. World Neurosurg. 2022;164:e1058–70. doi: 10.1016/j.wneu.2022.05.101
22. Hersh AM, Pennington Z, Hung B, Patel J, Goldsborough E, Schilling A, et al. Comparison of frailty metrics and the Charlson Comorbidity Index for predicting adverse outcomes in patients undergoing surgery for spine metastases. J Neurosurg Spine. 2021:1–9.
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