Medicina Intensiva  (English Edition) Medicina Intensiva  (English Edition)
Med Intensiva 2018;42:258-60 - Vol. 42 Num.4 DOI: 10.1016/j.medine.2017.03.012
Scientific Letter
Elderly patients in a Mexican intensive care unit: A retrospective analysis
El adulto mayor en una unidad de cuidados intensivos mexicana, análisis retrospectivo
L.A. Sánchez-Hurtadoa,b,, , B.C. Tejeda-Huezoa, S.S. Gómez-Floresa, A. Esquivel-Cháveza, A.A. Cano-Oviedoa, J.Á. Baltazar-Torresa
a Unidad de Cuidados Intensivos, Hospital de Especialidades Dr. Antonio Fraga Mouret, Centro Médico Nacional La Raza, Instituto Mexicano del Seguro Social, Mexico City, Mexico
b Unidad de Cuidados Intensivos, Instituto Nacional de Cancerología, Mexico City, Mexico
Dear Sir,

The world population is experiencing an aging process.1 Elderly people are defined as those that have reached 65 years of age.2 In Mexico such people represent 9% of the population—a figure that is expected to increase to about 28% by the year 2050.2 A longer life expectancy in turn is associated to an increased demand for medical care due to chronic diseases and their complications—in some cases within the setting of the Intensive Care Unit (ICU).1

In developed countries, elderly people can represent up to 50% of all admissions to the ICU.1,3,4 In Mexico the information referred to this age group is limited.

The present study describes the characteristics upon admission and their association to the outcome of elderly patients in the ICU of a tertiary hospital.

A retrospective observational study was carried out in patients of either gender aged 65 years or older and admitted to the ICU of a public hospital in the period between January 2015 and August 2016. Patients with first admission to the ICU were eligible for inclusion in the study, while readmissions were excluded. The following characteristics were recorded: age, gender, comorbidities, body mass index (BMI), reason for admission to the ICU, hospital stay prior to admission to the ICU, type of patient (surgical or medical), ICU stay, severity of disease as assessed by the APACHE II and SOFA scores, organ dysfunction upon admission as evaluated by the SOFA scale, need for and duration of mechanical ventilation, need for renal replacement therapy, and nosocomial infections. The follow-up endpoint was patient discharge from the ICU.

Quantitative variables were reported as the mean and standard deviation (SD) or median and interquartile range (IQR). Nominal variables were expressed as percentages. Continuous variables were compared using the Student's t-test or Mann–Whitney U-test, while nominal variables were compared using the chi-squared test or Fisher exact test. Statistical significance was considered for p<0.05. Multiple logistic regression analysis was performed with the different patient clinical characteristics and patient clinical condition at ICU discharge as outcome, with estimation of the respective odds ratio (OR) and corresponding 95% confidence interval (95%CI). The study was approved by the local research committee (R 2016-3501-9).

During the follow-up period a total of 929 patients were admitted to the ICU; of these, 243 (26.16%) were 65 years of age or older. A total of 230 subjects were considered for analysis while 13 were excluded due to readmission to intensive care. The mean patient age was 72.86±6.01 years; 69.1% (n=159) were males and 30.9% (n=71) females. The median BMI was 26.76kg/m2 (IQR 24.9–30.9). The main reasons for admission to the ICU were ischemic heart disease (37.82%; n=87), septic shock (19.56%; n=45), aortic surgery (12.17%; n=28), hemorrhagic shock (11.74%; n=27) and high-risk surgery (9.56%; n=22). The patients were grouped according to clinical condition at discharge from the ICU (Table 1). The patients that died in the ICU were older (p=0.0001), had more severe acute disease as rated by the APACHE II scale (p=0.0001), and suffered greater organ dysfunction upon admission as evidenced by the SOFA score (p=0.0001). The most frequent organ dysfunctions among the patients that died were of a neurological, hemodynamic, renal and hematological nature. The need for and duration of mechanical ventilation were greater among the patients that died (p<0.0001). Renal replacement therapy was used in only 10.43% of the cases (n=24), and the mortality rate was higher among those patients that required such therapy (p=0.04). The mortality rate in the ICU was 24.3% (n=56). Lastly, nosocomial infections were more prevalent among the patients that died (p=0.01).

Table 1.

General characteristics of the study sample.

  Total  Survivors  Deceased  p-Value 
  n=230  n=174  n=56   
Age in years, mean±SD  72.86±6.00  71.91±5.69  75.80±6.02  0.0001a 
Males, n (%)  159 (69.1)  119 (68.4)  40 (71.4)  0.67b 
Medical patients admitted, n (%)  105 (45.7)  84 (48.3)  21 (37.5)  0.16b 
Comorbidities, n (%)  195 (84.8)  151 (86.78)  44 (78.57)  0.13b 
Systemic arterial hypertension  150 (65.2)  117 (67.2)  33 (58.9)  0.26b 
Diabetes mellitus  91 (39.6)  68 (39.1)  23 (41.1)  0.79b 
Heart disease  87 (37.8)  64 (36.8)  23 (41.1)  0.57b 
COPD  38 (16.5)  25 (14.4)  13 (23.2)  0.12b 
Chronic renal failure  27 (11.7)  17 (9.8)  10 (17.9)  0.1b 
Cancer  15 (6.5)  11 (6.3)  4 (7.1)  0.76c 
APACHE II upon admission to ICU, median (IQR)  14 (9–21)  13 (8–18)  22 (12–26.75)  0.0001d 
SOFA upon admission to ICU, median (IQR)  4 (2–8)  3 (2–6)  8 (4–11)  0.0001d 
Organ dysfunction upon admission to ICU, n (%)
Neurological  42 (18.3)  25 (14.4)  17 (30.4)  0.007b 
Respiratory  179 (77.8)  133 (76.4)  38 (67.9)  0.37b 
Hemodynamic  111 (48.3)  73 (42)  46 (82.1)  0.01b 
Renal  91 (39.6)  62 (53.6)  39 (51.8)  0.03b 
Hepatic  30 (13)  22 (12.6)  8 (14.3)  0.75b 
Hematological  64 (27.8)  41 (23.6)  23 (41.1)  0.01b 
Need for mechanical ventilation, n (%)  156 (67.8)  101 (58)  55 (98.2)  0.0001b 
Days of mechanical ventilation, median (IQR)  1 (0–3)  1 (0–2)  2 (1–4)  0.0001d 
Need for renal replacement therapy, n (%)  24 (10.43)  13 (7)  9 (16.1)  0.04b 
Nosocomial infection, n (%)  24 (10.4)  13 (7.5)  11 (19.6)  0.01a 
Days of ICU stay, median (IQR)  2 (1–4)  2 (2–4)  2 (1–5.75)  0.27d 
Body mass index in kg/m2, median (IQR)  26.76 (24.91–30.09)  26.86 (24.99–30.08)  26.44 (24.86–30.24)  0.72d 

APACHE II: Acute Physiology and Chronic Health Evaluation II; SD: standard deviation; COPD: chronic obstructive pulmonary disease; IQR: interquartile range; SOFA: Sequential Organ Failure Assessment; ICU: Intensive Care Unit.

a

Student's t-test.

b

Chi-squared test.

c

Fisher exact test.

d

Mann–Whitney U-test.

The multivariate analysis identified those basal parameters showing significant differences in relation to clinical condition at discharge: patient age, disease severity (APACHE II score), the presence of acute respiratory failure and the need for mechanical ventilation were associated to increased mortality risk in the ICU (Table 2).

Table 2.

Risk factors for mortality in the Intensive Care Unit among elderly patients. Multivariate analysis.

  OR  95%CI  p-Value 
APACHE II  1.09  1.04–1.14  0.001 
Age (years)  1.108  1.04–1.18  0.001 
ARF  10.17  2.31–44.65  0.002 
Mechanical ventilation  17.45  2.31–134.91  0.002 

APACHE II: Acute Physiology and Chronic Health Evaluation II; 95%CI: 95% confidence interval; OR: odds ratio; ARF: acute respiratory failure.

Hosmer–Lemeshow χ2: 7.0; p=0.53, aROC 0.86 (95%CI 0.81–0.91); p0.0001.

The present study evaluated the clinical and mortality characteristics of elderly patients admitted to the ICU of a public hospital in Mexico. We found older age, greater acute disease severity (APACHE II score), a greater presence of acute respiratory failure, and a greater need for mechanical ventilation to be correlated to increased mortality risk in the ICU. The mortality rate in our ICU was similar to that reported in other Latin American countries and in other parts of the world.5–8 It has been seen that the mortality among patients aged 65 years or older is slightly greater or similar to that found in younger patients after adjusting for confounding variables. In this regard, age may contribute less to mortality risk than the severity of disease—though this circumstance was not evidenced in our series.5,9 The clinical characteristics that increase mortality risk in the ICU were similar to those described in other populations.4,6–10

Our study has some limitations, such as its retrospective design and the sample size involved. Nevertheless, it offers a global view of the characteristics and mortality risk factors in the ICU in our population. In conclusion, patient age, the severity of disease, the presence of acute respiratory failure, and the need for mechanical ventilation are risk factors for mortality in the ICU. The early identification of these risk factors may help improve the outcomes of elderly patients in the ICU.

References
1
A. López-Soto,E. Sacanella,J. Pérez Castejón,J.M. Nicolás
El anciano en la unidad de cuidados intensivos
Rev Esp Geriatr Gerontol, 44 (2009), pp. 27-33 http://dx.doi.org/10.1016/j.regg.2009.03.013
2
J. Villagordoa
Definición de envejecimiento y síndrome de fragilidad, características epidemiológicas del envejecimiento en México
Rev Endocrinol Nutr, 15 (2007), pp. 27-31
3
S. Carson
The epidemiology of critical illness in the elderly
Crit Care Clin, 19 (2003), pp. 605-617
4
L. Sánchez-Hurtado,C. Terán-Godínez,A. Herrera-Gómez,J. Arredondo-Armenta,H. Guevara-García,F. García-Guillén
Outcomes of elderly patients admitted to an oncological intensive care unit: a retrospective analysis
Eur Ger Med, 7 (2016), pp. 285-291
5
K. Sodhi,M.K. Singla,A. Shrivastava,N. Bansal
Do Intensive Care Unit treatment modalities predict mortality in geriatric patients: an observational study from an Indian Intensive Care Unit
Indian J Crit Care Med, 18 (2014), pp. 789-795 http://dx.doi.org/10.4103/0972-5229.146312
6
G. Collyer-Alves,G. Bezerra-da Silva Jr.,R. Siqueira-Athayde,J. Barbosa-Sobral,R. Salani-Mota,K.L. Soares-de Abreu
Risk factors for death among critically ill elderly patients
Rev Bras Ter Intensiva, 22 (2010), pp. 138-143
7
J.L. Reyes,J.V. Alonso,J. Fonseca,M.L. Santos,M.R. Jiménez,J. Braniff
Characteristics and mortality of elderly patients admitted to the Intensive Care Unit of a district hospital
Indian J Crit Care Med, 20 (2016), pp. 391-397 http://dx.doi.org/10.4103/0972-5229.186219
8
A. Boumendil,D. Somme,M. Garrouste-Orgeas,B. Guidet
Should elderly patients be admitted to the intensive care unit?
Intensive Care Med, 33 (2007), pp. 1252-1262 http://dx.doi.org/10.1007/s00134-007-0621-3
9
B. Nathanson,T. Higgins,M. Brennan,A. Kramer,M. Stark,D. Teres
Do elderly patients fare well in the ICU?
Chest, 139 (2011), pp. 825-831 http://dx.doi.org/10.1378/chest.10-1233
10
S. Rooij,A. Abu-Hanna,M. Levi,E. de Jonge
Factors that predict outcome of intensive care treatment in very elderly patients: a review
Crit Care, 9 (2005), pp. R307-R314 http://dx.doi.org/10.1186/cc3536

Please cite this article as: Sánchez-Hurtado LA, Tejeda-Huezo BC, Gómez-Flores SS, Esquivel-Chávez A, Cano-Oviedo AA, Baltazar-Torres JÁ. El adulto mayor en una unidad de cuidados intensivos mexicana, análisis retrospectivo. Med Intensiva. 2018;42:258–260.

Corresponding author. (L.A. Sánchez-Hurtado lashmd@gmail.com)
Copyright © 2017. Elsevier España, S.L.U. and SEMICYUC
Med Intensiva 2018;42:258-60 - Vol. 42 Num.4 DOI: 10.1016/j.medine.2017.03.012
Cookies Policy
x
To improve our services and products, we use cookies (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.