Open Access
Probabilistic analysis of adaptive experimental designs
(2014) Galbete Jiménez, Arkaitz; Moler Cuiral, José Antonio; Plo, Fernando; Estadística e Investigación Operativa; Estatistika eta Ikerketa Operatiboa
Un ensayo clínico es un experimento estadístico que consiste en comparar el comportamiento de dos tratamientos con objeto de establecer la superioridad de uno respecto al otro. En esta tesis se ha presentado un nuevo diseño de ensayo clínico adaptado a la respuesta, llamado diseño urna de Klein, que intenta combinar buenas propiedades éticas e inferenciales. A su vez, se han estudiado sus propiedades exactas y asintóticas y se compara el nuevo diseño con otros diseños destacados en la literatura estadística. Se realiza un estudio detallado de inferencia basado en la aleatorización desde un punto de vista exacto y asintótico. Finalmente, se analiza la inclusión de variables en el diseño.
Open Access
Metodo estatistikoak saiakera klinikoetan
(Universidad del País Vasco, 2014) Galbete Jiménez, Arkaitz; Estadística e Investigación Operativa; Estatistika eta Ikerketa Operatiboa
Saiakera klinikoak esperimentu estatistikoen artean kasu bereziak dira bere sekuentzia egiturarengatik eta saiakeraren unitateak gizakiak direlako. Honek erregulazio zorrotza eskatzen du eta datuen biltze eta tratatze prozesuan eragina du, askotan metodologia espezifikoa edo berria erabiliz gainera. Artikulu honetan, saiakera klinikoen diseinuan agertzen diren arazo estatistiko batzuk azaltzen dira, pazienteak tratamenduetan esleitzeko metodo esanguratsu batzuen bilduma bat egiten da eta azken urteotan garrantzia hartzen ari den inferentzia prozesu desberdin bat aurkezten da.
Open Access
The urgent surgery elderly mortality risk score: a simple mortality score
(Arán Ediciones, 2019) Eguaras Córdoba, Inés; Herrera Cabezón, Javier; Sánchez Acedo, Pablo; Galbete Jiménez, Arkaitz; Guillén Grima, Francisco; Ciencias de la Salud; Osasun Zientziak
Introduction: an increasing number of elderly patients undergo urgent abdominal surgery and this population has a higher risk of mortality.The main objective of the study was to identify mortality-associated factors in elderly patients undergoing abdominal surgery and to design a mortality scoring tool, the Urgent Surgery Elderly Mortality risk score (the USEM score). Patients and methods: this was a retrospective study using a prospective database. Patients > 65 years old that underwent urgent abdominal surgery were included. Risk factors for 30-day mortality were identified using multivariate regression analysis and weights assigned using the odds ratios (OR). A mortality score was derived from the aggregate of weighted scores. Model calibration and discrimination were judged using the receiver operating characteristics curves and the Hosmer-Lemeshow test. Results: in the present study, 4,255 patients were included with an 8.5% mortality rate. The risk factors significantly associated with mortality were American Society of Anesthesiologists (ASA) score, age, preoperative diagnosis (OR: 37.82 for intestinal ischemia, OR: 5.01 for colorectal perforation, OR: 6.73 for intestinal obstruction), surgical wound classification and open or laparoscopic surgery. A risk score was devised from these data for the estimation of the probability of survival in each patient. The area under the ROC curve (AUROC) for this score was 0.84 (95% CI: 0.82-0.86) and the AUROC correct was 0.83 (0.81-0.85). Conclusions: a simple score that uses five clinical variables predicts 30-day mortality. This model can assist surgeons in the initial evaluation of an elderly patient undergoing urgent abdominal surgery.
Open Access
Effect of exercise intervention on functional decline in very elderly patients during acute hospitalization: a randomized clinical trial
(American Medical Association, 2018) Martínez Velilla, Nicolás; Casas Herrero, Álvaro; Zambom Ferraresi, Fabrício; López Sáez de Asteasu, Mikel; Lucía, Alejandro; Galbete Jiménez, Arkaitz; García Baztán, Agurne; Alonso Renedo, Javier; González Glaría, Belén; Gonzalo Lázaro, María; Apezteguía Iráizoz, Itziar; Gutiérrez Valencia, Marta; Rodríguez Mañas, Leocadio; Izquierdo Redín, Mikel; Ciencias de la Salud; Osasun Zientziak
Importance: Functional decline is prevalent among acutely hospitalized older patients. Exercise and early rehabilitation protocols applied during acute hospitalization can prevent functional and cognitive decline in older patients. Objective: To assess the effects of an innovative multicomponent exercise intervention on the functional status of this patient population. Design, Setting, and Participants: A single-center, single-blind randomized clinical trial was conducted from February 1, 2015, to August 30, 2017, in an acute care unit in a tertiary public hospital in Navarra, Spain. A total of 370 very elderly patients undergoing acute-care hospitalization were randomly assigned to an exercise or control (usual-care) intervention. Intention-to-treat analysis was conducted. Interventions: The control group received usual-care hospital care, which included physical rehabilitation when needed. The in-hospital intervention included individualized moderate-intensity resistance, balance, and walking exercises (2 daily sessions). Main Outcomes and Measures: The primary end point was change in functional capacity from baseline to hospital discharge, assessed with the Barthel Index of independence and the Short Physical Performance Battery (SPPB). Secondary end points were changes in cognitive and mood status, quality of life, handgrip strength, incident delirium, length of stay, falls, transfer after discharge, and readmission rate and mortality at 3 months after discharge. Results: Of the 370 patients included in the analyses, 209 were women (56.5%); mean (SD) age was 87.3 (4.9) years. The median length of hospital stay was 8 days in both groups (interquartile range, 4 and 4 days, respectively). Median duration of the intervention was 5 days (interquartile range, 0); there was a mean (SD) of 5 (1) morning and 4 (1) evening sessions per patient. No adverse effects were observed with the intervention. The exercise intervention program provided significant benefits over usual care. At discharge, the exercise group showed a mean increase of 2.2 points (95% CI, 1.7-2.6 points) on the SPPB scale and 6.9 points (95% CI, 4.4-9.5 points) on the Barthel Index over the usual-care group. Hospitalization led to an impairment in functional capacity (mean change from baseline to discharge in the Barthel Index of -5.0 points (95% CI, -6.8 to -3.2 points) in the usual-care group, whereas the exercise intervention reversed this trend (1.9 points; 95% CI, 0.2-3.7 points). The intervention also improved the SPPB score (2.4 points; 95% CI, 2.1-2.7 points) vs 0.2 points; 95% CI, -0.1 to 0.5 points in controls). Significant intervention benefits were also found at the cognitive level of 1.8 points (95% CI, 1.3-2.3 points) over the usual-care group. Conclusions and Relevance: The exercise intervention proved to be safe and effective to reverse the functional decline associated with acute hospitalization in very elderly patients. Trial Registration: ClinicalTrials.gov identifier: NCT02300896.
Open Access
Socioeconomic inequalities in cardiometabolic control in patients with type 2 diabetes
(BioMed Central, 2018) Ibáñez Beroiz, Berta; Galbete Jiménez, Arkaitz; Goñi, María José; Forga, Lluís; Cambra Contin, Koldo; Ciencias de la Salud; Osasun Zientziak
Background: The aim of this study was to determine if the achievement of control targets in patients with type 2 diabetes was associated with personal socioeconomic factors and if these associations were sex-dependent. Methods: This cross-sectional, population-based study was conducted in Spain. Glycated haemoglobin (HbA1c) level and other clinical parameters were obtained from electronic primary care records (n = 32,638 cases). Socioeconomic status was determined using education level and yearly income. Among patients, having their HbA1c level checked during the previous year was considered as an indirect measure of the process of care, whereas tobacco use and clinical parameters such as HbA1c, low-density lipoprotein cholesterol (LDL-c) and blood pressure (BP) were considered intermediate control outcomes. General linear mixed effect models were used to assess associations. Results: The achievement of metabolic and cardiovascular control targets in patients with type 2 diabetes was associated with educational level and income, and socioeconomic gradients differed by sex. The probability of having had an HbA1c test performed in the previous year was higher in patients with lower education levels. Patients in the lowest income and education level categories were less likely to have reached the recommended HbA1c level. Males in the lowest education level categories were less likely to be non-smokers or to have achieved the blood pressure targets. In contrast, patients within the low income categories had a higher probability of reaching the recommended LDL-c level. Conclusions: Our results suggest the presence of socioeconomic inequalities in the achievement of cardiovascular and metabolic control that differed in direction and magnitude depending on the measured outcome and sex of the patient. These findings may help health professionals focus on high-risk individuals to decrease health inequalities.
Open Access
Assessing the impact of physical exercise on cognitive function in older medical patients during acute hospitalization: secondary analysis of a randomized trial
(PLoS, 2019) López Sáez de Asteasu, Mikel; Martínez Velilla, Nicolás; Zambom Ferraresi, Fabrício; Casas Herrero, Álvaro; Lusa Cadore, Eduardo; Galbete Jiménez, Arkaitz; Izquierdo Redín, Mikel; Ciencias de la Salud; Osasun Zientziak; Gobierno de Navarra / Nafarroako Gobernua
Background: Acute illness requiring hospitalization frequently is a sentinel event leading to long-term disability in older people. Prolonged bed rest increases the risk of developing cognitive impairment and dementia in acutely hospitalized older adults. Exercise protocols applied during acute hospitalization can prevent functional decline in older patients, but exercise benefits on specific cognitive domains have not been previously investigated. We aimed to assess the effects of a multicomponent exercise intervention for cognitive function in older adults during acute hospitalization. Methods and findings: We performed a secondary analysis of a single-blind randomized clinical trial (RCT) conducted from February 1, 2015, to August 30, 2017 in an Acute Care of the Elderly (ACE) unit in a tertiary public hospital in Navarre (Spain). 370 hospitalized patients (aged ≥75 years) were randomly allocated to an exercise intervention (n = 185) or a control (n = 185) group (usual care). The intervention consisted of a multicomponent exercise training program performed during 5–7 consecutive days (2 sessions/day). The usual care group received habitual hospital care, which included physical rehabilitation when needed. The main outcomes were change in executive function from baseline to discharge, assessed with the dual-task (i.e., verbal and arithmetic) Gait Velocity Test (GVT) and the Trail Making Test Part A (TMT-A). Changes in the Mini Mental State Examination (MMSE) test and verbal fluency ability were also measured after the intervention period. The physical exercise program provided significant benefits over usual care. At discharge, the exercise group showed a mean increase of 0.1 m/s (95% confidence interval [CI], 0.07, 0.13; p < 0.001) in the verbal GVT and 0.1 m/s (95% CI, 0.08, 0.13; p < 0.001) in the arithmetic GVT over usual care group. There was an apparent improvement in the intervention group also in the TMT-A score (−31.1 seconds; 95% CI, −49.5, −12.7 versus −3.13 seconds; 95% CI, −16.3, 10.2 in the control group; p < 0.001) and the MMSE score (2.10 points; 95% CI, 1.75, 2.46 versus 0.27 points; 95% CI, −0.08, 0.63; p < 0.001). Significant benefits were also observed in the exercise group for the verbal fluency test (mean 2.16 words; 95% CI, 1.56, 2.74; p < 0.001) over the usual care group. The main limitations of the study were patients’ difficulty in completing all the tasks at both hospital admission and discharge (e.g., 25% of older patients were unable to complete the arithmetic GVT, and 47% could not complete the TMT-A), and only old patients with relatively good functional capacity at preadmission (i.e., Barthel Index score ≥60 points) were included in the study. Conclusions: An individualized, multicomponent exercise training program may be an effective therapy for improving cognitive function (i.e., executive function and verbal fluency domains) in very old patients during acute hospitalization. These findings support the need for a shift from the traditional (bedrest-based) hospitalization to one that recognizes the important role of maintaining functional capacity and cognitive function in older adults, key components of intrinsic capacity.