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Seasonal variation in the occurrence of delirium in patients admitted to medical units of a general hospital in Italy

Published online by Cambridge University Press:  26 February 2013

Massimo Gallerani  and
Roberto Manfredini
Massimo Gallerani*
Affiliation:
Department of Internal Medicine, Hospital of Ferrara, Ferrara, Italy
Roberto Manfredini
Affiliation:
Clinica Medica, Department of Medical Sciences and Vascular Diseases Centre, University of Ferrara, Ferrara, Italy
*
Massimo Gallerani, MD, Department of Internal Medicine, Hospital of Ferrara, Corso Giovecca 203, 44100 Ferrara, Italy. Tel: +39‐0532‐236294Fax: +39‐0532‐236736 E‐mail: m.gallerani@ospfe.it
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Abstract

Objective

Delirium syndrome is common in the hospitalised population. However, data on its aetiological factors are scarce. Clinical observations suggest a relationship between delirium occurrence and seasons. The aim of study was to determine whether a seasonal variation exists in the occurrence of delirium events in‐hospital patients.

Methods

The study included all admissions to the medical units of the Hospital of Ferrara, Italy, between January 2002 and December 2010. On the basis of date admission, cases have been analysed for seasonal variation (four 3‐month intervals by seasons) by means of conventional statistics. Moreover, cases categorised into twelve 1‐month intervals were also analysed by means of a validated chronobiologic inferential method (single cosinor) to search for cyclic variability.

Results

During the analysed period, the hospital database contained 74 379 records referring to 42 625 subjects (52.7% females). Delirium diagnoses were 1300 (1.7% of total sample), 668 of whom in females (51.4%) and 632 in males (48.6%). Events of delirium were more frequent in winter and autumn (26.6 and 26.5%, respectively) than in spring (23.5%) and summer (23.4%). Chronobiological analysis yielded a significant peak of delirium events in January, when considering both the total raw number of cases and the percent of admissions.

Conclusions

The study seems to indicate in patients hospitalised in medical units, a higher rate of occurrence of delirium in autumn‐winter, similar to that reported for acute medical diseases. The role of possible underlying favouring or triggering factors deserves further research.

Keywords

chronobiologydeliriummedical unitsseasons
Type
Short Communications
Information
Acta Neuropsychiatrica , Volume 25 , Issue 3 , June 2013 , pp. 179 - 183
Copyright
Copyright © Scandinavian College of Neuropsychopharmacology 2013 

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References

1McCusker, J, Cole, M, Abrahamowicz, M, Primeau, F, Belzile, E. Delirium predicts 12‐month mortality. Arch Intern Med 2002;162:457–463.Google Scholar
2Lundström, M, Edlund, A, Karlsson, S, Brännström, B, Bucht, G, Gustafson, Y. A multifactorial intervention program reduces the duration of delirium, length of hospitalization, and mortality in delirious patients. J Am Geriatr Soc 2005;53:622–628.Google Scholar
3Siddiqi, N, House, AO, Holmes, JD. Occurrence and outcome of delirium in medical in‐patients: a systematic literature review. Age Ageing 2006;35:350–364.CrossRefGoogle ScholarPubMed
4Yang, FM, Marcantonio, ER, Inouye, SK et al. Phenomenological subtypes of delirium in older persons: patterns, prevalence, and prognosis. Psychosomatics 2009;50:248–254.Google Scholar
5Saxena, S, Lawley, D. Delirium in the elderly: a clinical review. Postgrad Med J 2009;85:405–413.Google Scholar
6Mittal, V, Muralee, S, Williamson, D et al. Review: delirium in the elderly: a comprehensive review. Am J Alzheimers Dis Other Demen 2011;26:97–109.Google Scholar
7Balan, S, Leibovitz, A, Freedman, L et al. Seasonal variation in the incidence of delirium among the patients of a geriatric hospital. Arch Gerontol Geriatr 2001;33:287–293.Google Scholar
8Mojòn, A, Fernàndez, JR, Hermida, RC. Chronolab: an interactive software package for chronobiologic time series analysis written for the Macintosh computer. Chronobiol Int 1992;9:403–412.Google Scholar
9Bachman, D, Rabins, P. “Sundowning” and other temporally associated agitation states in dementia patients. Annu Rev Med 2006;57:499–511.Google Scholar
10Dodek, PM, Norena, M, Keenan, SP, Teja, A, Wong, H. Intensive care unit admissions for community‐acquired pneumonia are seasonal but are not associated with weather or reports of influenza‐like illness in the community. J Crit Care 2011;26:228–233.Google Scholar
11Donaldson, GC, Goldring, JJ, Wedzicha, JA. Influence of season on exarcebation characteristics in patients with COPD. Chest 2012;141:94–100.Google Scholar
12Manfredini, R, Manfredini, F, Boari, B et al. Seasonal and weekly patterns of hospital admissions for nonfatal and fatal myocardial infarction. Am J Emerg Med 2009;27:1097–1103.Google Scholar
13Barnett, AG, de Looper, M, Fraser, JF. The seasonality in heart failure deaths and total cardiovascular deaths. Aust N Z J Public Health 2008;32:408–413.Google Scholar
14Gallerani, M, Boari, B, Manfredini, F, Manfredini, R. Seasonal variation in heart failure hospitalization. Clin Cardiol 2011;34:389–394.Google Scholar
15Gallerani, M, Boari, B, Smolensky, MH et al. Seasonal variation in occurrence of pulmonary embolism: analysis of the database of the Emilia‐Romagna region, Italy. Chronobiol Int 2007;24:143–160.Google Scholar
16Manfredini, R, Manfredini, F, Boari, B et al. Temporal patterns of hospital admissions for transient ischemic attack. A retrospective population‐based study in the Emilia‐Romagna region of Italy. Clin Appl Thromb Hemost 2010;16:153–160.Google Scholar
17Gallerani, M, Manfredini, R, Ricci, L et al. Chronobiological aspects of acute cerebrovascular diseases. Acta Neurol Scand 1993;87:482–487.Google Scholar
18Spencer, FA, Goldberg, RJ, Becker, RC, Gore, JM. Seasonal distribution of acute myocardial infarction in the second National Registry of Myocardial Infarction. J Am Coll Cardiol 1998;31:1226–1233.Google Scholar
19Boulay, F, Berthier, F, Sisteron, O, Gendreike, Y, Gibelin, P. Seasonal variation in chronic heart failure hospitalizations and mortality in France. Circulation 1999;100:280–286.Google Scholar
20Dentali, F, Ageno, W, Rancan, E et al. Seasonal and monthly variability in the incidence of venous thromboembolism: a systematic review and a meta‐analysis of the literature. Thromb Haemost 2011;106:439–447.Google Scholar
21Anderson, JE. Seasonality of symptomatic bacterial urinary infections in women. J Epidemiol Community Health 1983;37:286–290.Google Scholar
22Freeman, JT, Anderson, DJ, Sexton, DJ. Seasonal peaks in Escherichia coli infections: possible explanations and implications. Clin Microbiol Infect 2009;15:951–953.Google Scholar
23Chazan, B, Colodner, R, Edelstein, H, Raz, R. Seasonal variation in Escherichia coli blood stream infections in northern Israel. Clin Microbiol Infect 2011;17:851–854.Google Scholar
24Inouye, SK. Delirium in older persons. N Engl J Med 2006;354:1157–1165.Google Scholar
25Lin, RY, Heacock, LC, Bhargave, GA, Fogel, JF. Clinical associations of delirium in hospitalized adult patients and the role of on admission presentation. Int J Geriatr Psychiatry 2010;25:1022–1029.Google Scholar