Influence of depression on survival of colorectal cancer patients drawn from a large prospective cohort.

OBJECTIVE: The prevalence of depressive symptoms immediately after the diagnosis of colorectal cancer (CRC) is high and has important implications both psychologically and on the course of the disease. The aim of this study is to analyse the association between depressive symptoms and CRC survival at 5 years after diagnosis. METHODS: This multicentre, prospective, observational cohort study was conducted on a sample of 2602 patients with CRC who completed the Hospital Anxiety and Depression Scale (HADS-D) at 5 years of follow-up. Survival was analysed using the Kaplan-Meier method and Cox regression models. RESULTS: According to our analysis, the prevalence of depressive symptoms after a CRC diagnosis was 23.8%. The Cox regression analysis identified depression as an independent risk factor for survival (HR = 1.47; 95% CI: 1.21-1.8), a finding which persisted after adjusting for sex (female: HR = 0.63; 95% CI: 0.51-0.76), age (>70 years: HR = 3.78; 95% CI: 1.94-7.36), need for help (yes: HR = 1.43; 95% CI: 1.17-1.74), provision of social assistance (yes: HR = 1.46; 95% CI: 1.16-1.82), tumour size (T3-T4: HR = 1.56; 95% CI: 1.22-1.99), nodule staging (N1-N2: HR = 2.46; 95% CI: 2.04-2.96), and diagnosis during a screening test (yes: HR = 0.71; 95% CI: 0.55-0.91). CONCLUSIONS: There is a high prevalence of depressive symptoms in patients diagnosed with CRC. These symptoms were negatively associated with the survival rate independently of other clinical variables. Therefore, patients diagnosed with CRC should be screened for depressive symptoms to ensure appropriate treatment can be provided.

Influence of Diagnostic Delay on Survival Rates for Patients with Colorectal Cancer.

Colorectal cancer affects men and women alike. Sometimes, due to clinical-pathological factors, the absence of symptoms or the failure to conduct screening tests, its diagnosis may be delayed. However, it has not been conclusively shown that such a delay, especially when attributable to the health system, affects survival. The aim of the present study is to evaluate the overall survival rate of patients with a delayed diagnosis of colorectal cancer. This observational, prospective, multicenter study was conducted at 22 public hospitals located in nine Spanish provinces. For this analysis, 1688 patients with complete information in essential variables were included. The association between diagnostic delay and overall survival at five years, stratified according to tumor location, was estimated by the Kaplan-Meier method. Hazard ratios for this association were estimated using multivariable Cox regression models. The diagnostic delay ≥ 30 days was presented in 944 patients. The presence of a diagnostic delay of more than 30 days was not associated with a worse prognosis, contrary to a delay of less than 30 days (HR: 0.76, 0.64-0.90). In the multivariate analysis, a short delay maintained its predictive value (HR: 0.80, 0.66-0.98) regardless of age, BMI, Charlson index or TNM stage. A diagnostic delay of less than 30 days is an independent factor for short survival in patients with CRC. This association may arise because the clinical management of tumors with severe clinical characteristics and with a poorer prognosis are generally conducted more quickly.

Risk scores to predict mortality 2 and 5 years after surgery for colorectal cancer in elderly patients.

BACKGROUND: The aim of this study was to identify predictors of mortality in elderly patients undergoing colorectal cancer surgery and to develop a risk score. METHODS: This was an observational prospective cohort study. Individuals over 80 years diagnosed with colorectal cancer and treated surgically were recruited in 18 hospitals in the Spanish National Health Service, between June 2010 and December 2012, and were followed up 1, 2, 3, and 5 years after surgery. Sociodemographic and clinical data were collected. The primary outcomes were mortality at 2 and between 2 and 5 years after the index admission. RESULTS: The predictors of mortality 2 years after surgery were haemoglobin ≤ 10 g/dl and colon locations (HR 1.02; CI 0.51-2.02), ASA class of IV (HR 3.55; CI 1.91-6.58), residual tumour classification of R2 (HR 7.82; CI 3.11-19.62), TNM stage of III (HR 2.14; CI 1.23-3.72) or IV (HR 3.21; CI 1.47-7), LODDS of more than - 0.53 (HR 3.08; CI 1.62-5.86)) and complications during admission (HR 1.73; CI 1.07-2.80). Between 2 and 5 years of follow-up, the predictors were no tests performed within the first year of follow-up (HR 2.58; CI 1.21-5.46), any complication due to the treatment within the 2 years of follow-up (HR 2.47; CI 1.27-4.81), being between 85 and 89 and not having radiotherapy within the second year of follow-up (HR 1.60; CI 1.01-2.55), no colostomy closure within the 2 years of follow-up (HR 4.93; CI 1.48-16.41), medical complications (HR 1.61; CI 1.06-2.44), tumour recurrence within the 2 years of follow-up period (HR 3.19; CI 1.96-5.18), and readmissions at 1 or 2 years of follow-up after surgery (HR 1.44; CI 0.86-2.41). CONCLUSION: We have identified variables that, in our sample, predict mortality 2 and between 2 and 5 years after surgery for colorectal cancer older patients. We have also created risks scores, which could support the decision-making process. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02488161 .

Predictors of mortality of COVID-19 in the general population and nursing homes.

The factors that predispose an individual to a higher risk of death from COVID-19 are poorly understood. The goal of the study was to identify factors associated with risk of death among patients with COVID-19. This is a retrospective cohort study of people with laboratory-confirmed SARS-CoV-2 infection from February to May 22, 2020. Data retrieved for this study included patient sociodemographic data, baseline comorbidities, baseline treatments, other background data on care provided in hospital or primary care settings, and vital status. Main outcome was deaths until June 29, 2020. In the multivariable model based on nursing home residents, predictors of mortality were being male, older than 80 years, admitted to a hospital for COVID-19, and having cardiovascular disease, kidney disease or dementia while taking anticoagulants or lipid-lowering drugs at baseline was protective. The AUC was 0.754 for the risk score based on this model and 0.717 in the validation subsample. Predictors of death among people from the general population were being male and/or older than 60 years, having been hospitalized in the month before admission for COVID-19, being admitted to a hospital for COVID-19, having cardiovascular disease, dementia, respiratory disease, liver disease, diabetes with organ damage, or cancer while being on anticoagulants was protective. The AUC was 0.941 for this model's risk score and 0.938 in the validation subsample. Our risk scores could help physicians identify high-risk groups and establish preventive measures and better follow-up for patients at high risk of dying.ClinicalTrials.gov Identifier: NCT04463706.

Factors that Influence Treatment Delay for Patients with Breast Cancer.

INTRODUCTION: The diagnosis or treatment of breast cancer is sometimes delayed. A lengthy delay may have a negative psychological impact on patients. The aim of our study was to evaluate the sociodemographic, clinical and pathological factors associated with delay in the provision of surgical treatment for localised breast cancer, in a prospective cohort of patients. METHODS: This observational, prospective, multicentre study was conducted in ten hospitals belonging to the Spanish national public health system, located in four Autonomous Communities (regions). The study included 1236 patients, diagnosed through a screening programme or found to be symptomatic, between April 2013 and May 2015. The study variables analysed included each patient's personal history, care situation, tumour history and data on the surgical intervention, pathological anatomy, hospital admission and follow-up. Treatment delay was defined as more than 30 days elapsed between biopsy and surgery. RESULTS: Over half of the study population experienced surgical treatment delay. This delay was greater for patients with no formal education and among widows, persons not requiring assistance for usual activities, those experiencing anxiety or depression, those who had a high BMI or an above-average number of comorbidities, those who were symptomatic, who did not receive NMR spectroscopy, who presented a histology other than infiltrating ductal carcinoma or who had poorly differentiated carcinomas. CONCLUSIONS: Certain sociodemographic and clinical variables are associated with surgical treatment delay. This study identifies factors that influence surgical delays, highlighting the importance of preventing these factors and of raising awareness among the population at risk and among health personnel.

Impact of reducing the duration of antibiotic treatment on the long-term prognosis of community acquired pneumonia.

BACKGROUND: The optimal duration of antibiotic treatment for community-acquired pneumonia (CAP) is not well established. The aim of this study was to assess the impact of reducing the duration of antibiotic treatment on long-term prognosis in patients hospitalized with CAP. METHODS: This was a multicenter study assessing complications developed during 1 year of patients previously hospitalized with CAP who had been included in a randomized clinical trial concerning the duration of antibiotic treatment. Mortality at 90 days, at 180 days and at 1 year was analyzed, as well as new admissions and cardiovascular complications. A subanalysis was carried out in one of the hospitals by measuring C-reactive protein (CRP), procalcitonin (PCT) and proadrenomedullin (proADM) at admission, at day 5 and at day 30. RESULTS: A total of 312 patients were included, 150 in the control group and 162 in the intervention group. Ninety day, 180 day and 1-year mortality in the per-protocol analysis were 8 (2.57%), 10 (3.22%) and 14 (4.50%), respectively. There were no significant differences between both groups in terms of 1-year mortality (p = 0.94), new admissions (p = 0.84) or cardiovascular events (p = 0.33). No differences were observed between biomarker level differences from day 5 to day 30 (CRP p = 0.29; PCT p = 0.44; proADM p = 0.52). CONCLUSIONS: Reducing antibiotic treatment in hospitalized patients with CAP based on clinical stability criteria is safe, without leading to a greater number of long-term complications.

Gender differences in stage at diagnosis and preoperative radiotherapy in patients with rectal cancer.

BACKGROUND: Few studies have examined gender differences in the clinical management of rectal cancer. We examine differences in stage at diagnosis and preoperative radiotherapy in rectal cancer patients. METHODS: A prospective cohort study was conducted in 22 hospitals in Spain including 770 patients undergoing surgery for rectal cancer. Study outcomes were disseminated disease at diagnosis and receiving preoperative radiotherapy. Age, comorbidity, referral from a screening program, diagnostic delay, distance from the anal verge, and tumor depth were considered as factors that might explain gender differences in these outcomes. RESULTS: Women were more likely to be diagnosed with disseminated disease among those referred from screening (odds ratio, confidence interval 95% (OR, CI = 7.2, 0.9-55.8) and among those with a diagnostic delay greater than 3 months (OR, CI = 5.1, 1.2-21.6). Women were less likely to receive preoperative radiotherapy if they were younger than 65 years of age (OR, CI = 0.6, 0.3-1.0) and if their tumors were cT3 or cT4 (OR, CI = 0.5, 0.4-0.7). CONCLUSIONS: The gender-specific sensitivity of rectal cancer screening tests, gender differences in referrals and clinical reasons for not prescribing preoperative radiotherapy in women should be further examined. If these gender differences are not clinically justifiable, their elimination might enhance survival.

Type and Consequences of Short-Term Complications in Colon Cancer Surgery, Focusing on the Oldest Old.

BACKGROUND: While the proportion of colon cancer occurring in older patients is expected to increase, these patients may have more complications that may lead to serious consequences. The aim of this study was assess postoperative complications and their short-term consequences in colon cancer surgery according to age. PATIENTS AND METHODS: Patients undergoing surgery for primary invasive colon cancer in 22 centers between June 2010 and December 2012 were included. Presurgical and surgical variables were analyzed, and in-hospital major postoperative complications and its most serious consequence (no relevant, transfusion, reintervention, admission to the intensive care unit, or death) were estimated according to age group. Chi-square tests were used to analyze the possible associations between variables and age groups. RESULTS: Data from 1976 patients, mean (range) age 68 (24-97) years, 62% men, were analyzed; 52.2% were aged > 69 years and 17.7% were aged > 79 years. The complication rate was 25.3%, reaching 30.9% in those aged ≥ 80 years. Older age was associated with a higher rate of postoperative infections during the hospital stay. The most common surgical complication in patients aged > 85 years was dehiscence of the anastomosis (11.5%). About 5% of patients with major complications died in the hospital (11.1% of those aged 80-84 years and 14.3% aged > 85 years). Among patients aged > 85 years, 38.1% required transfusions. CONCLUSION: Older patients should receive appropriate functional preparation before the intervention, and when the risks of the intervention outweigh the potential benefits, a nonsurgical approach may be preferable.

Wnt-11 as a Potential Prognostic Biomarker and Therapeutic Target in Colorectal Cancer.

The expression of the secreted factor Wnt-11 is elevated in several types of cancer, including colorectal cancer, where it promotes cancer cell migration and invasion. Analysis of colorectal cancer gene expression databases associated WNT11 mRNA expression with increased likelihood of metastasis in a subset of patients. WNT11 expression was correlated with the expression of the Wnt receptors FZD6, RYK, and PTK7, and the combined expression of WNT11, FZD6 and RYK or PTK7 was associated with an increased risk of 5-year mortality rates. Immunohistochemical analysis of Wnt-11 in a cohort of 357 colorectal cancer patients found significantly higher Wnt-11 levels in tumors, compared with benign tissue. Elevated Wnt-11 levels occurred more frequently in rectal tumors than in colonic tumors and in tumors from women than men. In univariate analysis, increased Wnt-11 expression was also associated with tumor invasion and increased 5-year mortality. High Wnt-11 levels were not associated with high levels of nuclear ß-catenin, suggesting Wnt-11 is not simply an indicator for activation of ß-catenin-dependent signaling. Expression of Wnt-11 in colorectal cancer cell lines expressing low endogenous Wnt-11 inhibited ß-catenin/Tcf activity and increased ATF2-dependent transcriptional activity. WNT11 gene silencing and antibody-mediated inhibition of Wnt-11 in colorectal cancer cell lines expressing high Wnt-11 reduced their capacity for invasion. Together, these observations suggest that Wnt-11 could be a potential target for the treatment of patients with invasive colorectal cancer.

Biological and prognostic differences between symptomatic colorectal carcinomas and those detected by screening.

INTRODUCTION: Few studies have been conducted to establish the relationship between colorectal cancer screening programmes and survival adjusting by stage and, to determine whether there are differences, at a biological level, between the tumours of asymptomatic and symptomatic patients. Accordingly, the aim of this study is to evaluate clinical, biological and survival differences between symptomatic colorectal tumours and those detected by screening. STUDY METHOD: A prospective cohort study was performed of patients subjected to surgical intervention during the period 2010-2012, at different hospitals in Spain. In every case, clinical, pathological, biological and survival-related variables were obtained. RESULTS: A total of 2634 patients from the CARESS-CCR cohort were analysed; of these, 220 were diagnosed through screening. The asymptomatic patients were younger, had a higher Body Mass Index (BMI), a lower degree of perineural invasion and a less advanced T stage and nodular stage, and the tumour was frequently located on the right side of the colon. All of these differences were statistically significant. The serum tumour marker carbohydrate antigen 19.9 (CA 19.9) was found more frequently in the symptomatic patients (p < 0.05). However, no significant differences were found regarding the markers of tumour biology: Ki67 (proliferation), CD105 (angiogenesis) and the Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay (apoptosis). The patients with asymptomatic tumours had a lower mortality at five years than those diagnosed presenting symptoms. CONCLUSIONS: The detection method employed influenced the survival of patients with colorectal cancer and there were no significant biological differences between the study groups.

COPD classification models and mortality prediction capacity.

OBJECTIVE: Our aim was to assess the impact of comorbidities on existing COPD prognosis scores. PATIENTS AND METHODS: A total of 543 patients with COPD (FEV1 <80% and FEV1/FVC <70%) were included between January 2003 and January 2004. Patients were stable for at least 6 weeks before inclusion and were followed for 5 years without any intervention by the research team. Comorbidities and causes of death were established from medical reports or information from primary care medical records. The GOLD system and the body mass index, obstruction, dyspnea and exercise (BODE) index were used for COPD classification. Patients were also classified into four clusters depending on the respiratory disease and comorbidities. Cluster analysis was performed by combining multiple correspondence analyses and automatic classification. Receiver operating characteristic curves and the area under the curve (AUC) were calculated for each model, and the DeLong test was used to evaluate differences between AUCs. Improvement in prediction ability was analyzed by the DeLong test, category-free net reclassification improvement and the integrated discrimination index. RESULTS: Among the 543 patients enrolled, 521 (96%) were male, with a mean age of 68 years, mean body mass index 28.3 and mean FEV1% 55%. A total of 167 patients died during the study follow-up. Comorbidities were prevalent in our cohort, with a mean Charlson index of 2.4. The most prevalent comorbidities were hypertension, diabetes mellitus and cardiovascular diseases. On comparing the BODE index, GOLDABCD, GOLD2017 and cluster analysis for predicting mortality, cluster system was found to be superior compared with GOLD2017 (0.654 vs 0.722, P=0.006), without significant differences between other classification models. When cardiovascular comorbidities and chronic renal failure were added to the existing scores, their prognostic capacity was statistically superior (P<0.001). CONCLUSION: Comorbidities should be taken into account in COPD management scores due to their prevalence and impact on mortality.

Factors Associated with Prolonged Patient-Attributable Delay in the Diagnosis of Colorectal Cancer.

PURPOSE: The delayed diagnosis of colorectal cancer (CRC) may be attributable to sociodemographic characteristics, to aspects of tumour histopathology or to the functioning of the health system. We seek to determine which of these factors most influences prolonged patient-attributable delay (PPAD) in the diagnosis and treatment of CRC. MATERIALS AND METHODS: A prospective, multicentre observational study was conducted in 22 Spanish hospitals. In total, 1,785 patients were recruited to the study between 2010 and 2012 and underwent elective or urgent surgery. PPAD is considered to occur when the time elapsed between a patient presenting the symptom and him/her seeking attention from the primary care physician or hospital emergency department exceeds 180 days. A bivariate analysis was performed to assess differences in variables segmented by tumour location and patient delay. Multivariate logistic regression analysis was performed on the outcome variable, PPAD. RESULTS: The rate of PPAD among this population was 12.1%. PPAD was significantly associated with altered bowel rhythm (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.02 to 1.83) and with adenocarcinoma histology, in comparison with mucinous adenocarcinoma (OR, 2.03; 95% CI, 1.11 to 3.71). Other sociocultural factors and clinicopathological features were not independent predictors of PPAD. CONCLUSION: Many patients do not consider altered bowel rhythm an alarming symptom, warranting a visit to the doctor. PPAD could be reduced by improving health education, raising awareness of CRC-related symptoms.

Health services research in patients with breast cancer (CAMISS-prospective): study protocol for an observational prospective study.

BACKGROUND: Though breast cancer remains a major health problem, there is a lack of information on health care provided to patients with this disease and associated costs. In addition, there is a need to update and validate risk stratification tools in Spain. Our purpose is to evaluate the health services provided for breast cancer in Spain, from screening and diagnosis to treatment and prognosis. METHODS: Prospective cohort study involving 13 hospitals in Spain with a follow-up period of up to 5 years after diagnostic biopsy. Eligibility criteria: Patients diagnosed with breast cancer between April 2013 and May 2015 that have consented to participate in the study. DATA COLLECTION: Data will be collected on the following: pre-intervention medical history, biological, clinical, and sociodemographic characteristics, mode of cancer detection, hospital admission, treatment, and outcomes up to 5 years after initial treatment. Questionnaires about quality of life (EuroQoL EQ-5D-5 L, the European Organization For Research And Treatment Of Cancer Core Quality Of Life Questionnaire EORTC QLQ-C30 join to the specific breast cancer module (QLQ-BR23), as well as Hospital Anxiety and Depression Scale were completed by the patients before the beginning of the initial treatment and at the end of follow-up period, 2 years later. The end-points of the study were changes in health-related quality of life, recurrence, complications and readmissions at 2 and 5 years after initial treatment. STATISTICAL ANALYSIS: Descriptive statistics will be calculated and multivariate models will be used where appropriate to adjust for potential confounders. In order to create and validate a prediction model, split validation and bootstrapping will be performed. Cost analysis will be carried out from the perspective of a national health system. DISCUSSION: The results of this coordinated project are expected to generate scientifically valid and clinically and socially important information to inform the decision-making of managers and the authorities responsible for ensuring equality in care processes as well in health outcomes. For clinicians, clinical prediction rules will be developed which are expected to serve as the basis for the development of software applications. TRIAL REGISTRATION: NCT02439554 . Date of registration: May 8, 2015 (retrospectively registered) .

Validity of the CR-POSSUM model in surgery for colorectal cancer in Spain (CCR-CARESS study) and comparison with other models to predict operative mortality.

BACKGROUND: To validate and recalibrate the CR- POSSUM model and compared its discriminatory capacity with other European models such as POSSUM, P-POSSUM, AFC or IRCS to predict operative mortality in surgery for colorectal cancer. METHODS: Prospective multicenter cohort study from 22 hospitals in Spain. We included patients undergoing planned or urgent surgery for primary invasive colorectal cancers between June 2010 and December 2012 (N = 2749). Clinical data were gathered through medical chart review. We validated and recalibrated the predictive models using logistic regression techniques. To calculate the discriminatory power of each model, we estimated the areas under the curve - AUC (95% CI). We also assessed the calibration of the models by applying the Hosmer-Lemeshow test. RESULTS: In-hospital mortality was 1.5% and 30-day mortality, 1.7%. In the validation process, the discriminatory power of the CR-POSSUM for predicting in-hospital mortality was 73.6%. However, in the recalibration process, the AUCs improved slightly: the CR-POSSUM reached 75.5% (95% CI: 67.3-83.7). The discriminatory power of the CR-POSSUM for predicting 30-day mortality was 74.2% (95% CI: 67.1-81.2) after recalibration; among the other models the POSSUM had the greatest discriminatory power, with an AUC of 77.0% (95% CI: 68.9-85.2). The Hosmer-Lemeshow test showed good fit for all the recalibrated models. CONCLUSION: The CR-POSSUM and the other models showed moderate capacity to discriminate the risk of operative mortality in our context, where the actual operative mortality is low. Nevertheless the IRCS might better predict in-hospital mortality, with fewer variables, while the CR-POSSUM could be slightly better for predicting 30-day mortality. TRAIL REGISTRATION: Registered at: ClinicalTrials.gov Identifier: NCT02488161.

COPD is a clear risk factor for increased use of resources and adverse outcomes in patients undergoing intervention for colorectal cancer: a nationwide study in Spain.

BACKGROUND: We hypothesized that patients undergoing surgery for colorectal cancer (CRC) with COPD as a comorbidity would consume more resources and have worse in-hospital outcomes than similar patients without COPD. Therefore, we compared different aspects of the care process and short-term outcomes in patients undergoing surgery for CRC, with and without COPD. METHODS: This was a prospective study and it included patients from 22 hospitals located in Spain - 472 patients with COPD and 2,276 patients without COPD undergoing surgery for CRC. Clinical variables, postintervention intensive care unit (ICU) admission, use of invasive mechanical ventilation, and postintervention antibiotic treatment or blood transfusion were compared between the two groups. The reintervention rate, presence and type of complications, length of stay, and in-hospital mortality were also estimated. Hazard ratio (HR) for hospital mortality was estimated by Cox regression models. RESULTS: COPD was associated with higher rates of in-hospital complications, ICU admission, antibiotic treatment, reinterventions, and mortality. Moreover, after adjusting for other factors, COPD remained clearly associated with higher and earlier in-hospital mortality. CONCLUSION: To reduce in-hospital morbidity and mortality in patients undergoing surgery for CRC and with COPD as a comorbidity, several aspects of perioperative management should be optimized and attention should be given to the usual comorbidities in these patients.

Factors that influence treatment delay in patients with colorectal cancer.

A prospective study was performed of patients diagnosed with colorectal cancer (CRC), distinguishing between colonic and rectal location, to determine the factors that may provoke a delay in the first treatment (DFT) provided.2749 patients diagnosed with CRC were studied. The study population was recruited between June 2010 and December 2012. DFT is defined as time elapsed between diagnosis and first treatment exceeding 30 days.Excessive treatment delay was recorded in 65.5% of the cases, and was more prevalent among rectal cancer patients. Independent predictor variables of DFT in colon cancer patients were a low level of education, small tumour, ex-smoker, asymptomatic at diagnosis and following the application of screening. Among rectal cancer patients, the corresponding factors were primary school education and being asymptomatic.We conclude that treatment delay in CRC patients is affected not only by clinicopathological factors, but also by sociocultural ones. Greater attention should be paid by the healthcare provider to social groups with less formal education, in order to optimise treatment attention.

Smoking may increase the risk of hospitalization due to influenza.

BACKGROUND: Smoking may facilitate influenza virus infections and their severity. The objective was to investigate the risk of hospitalization due to influenza in Spanish smokers and ex-smokers. METHODS: We carried out a multicentre, case-control study in 2011. Cases [patients ≥ 18 years hospitalized > 24 h with real time polymerase chain reaction (RT-PCR)-confirmed influenza] were selected from 29 Spanish hospitals. For each case, we selected an outpatient aged ≥ 18 years with RT-PCR-confirmed influenza matched by age (±5 years), date of hospitalization of the case (±10 days) and province of residence. We collected epidemiological variables, comorbidities and the smoking history. The risk of hospitalization due to smoking was determined by the adjusted odds ratio (aOR) using logistic regression. RESULTS: We studied 471 hospitalized cases and 476 outpatient cases. Hospitalized cases had a higher frequency of influenza risk factors compared with outpatient cases. Hospitalized cases had a higher frequency of smoking (30.9% vs. 17.1%) and being ex-smokers (29.3% vs. 25.3%). Current smoking (aOR = 2.18, 95% CI: 1.23-3.87) and being an ex-smoker (aOR = 1.73, 95% CI: 1.07-2.82) were associated with the risk of hospitalization. CONCLUSIONS: Smoking may increase the risk of hospitalization in smokers and ex-smokers when infected by the influenza virus. Smoking prevention could reduce hospitalizations. Influenza vaccination is recommended for smokers.

High Body Mass Index as a Risk Factor for Hospitalization Due to Influenza: A Case-Control Study. / Índice de masa corporal elevado como factor de riesgo de hospitalización por gripe: estudio de casos y controles.

INTRODUCTION: Obesity has emerged as a significant independent predictor of severity in pandemic influenzaA (H1N1)pdm09. The aim of this study was to investigate the association between body mass index (BMI) and the risk of hospitalization due to influenza. METHODS: Hospitalized patients (n=755) with laboratory-confirmed influenza were individually matched by age, admission/visit date, and province with an outpatient (n=783) with laboratory-confirmed influenza and an outpatient control (n=950). We compared the BMI using conditional logistic regression adjusted for potential confounding factors (aOR). The population attributable fraction (PAF) was calculated. RESULTS: A higher BMI was associated with an increased risk of hospitalization compared to both outpatient cases (aOR=1.11; 95%CI: 1.07-1.16) and outpatient controls (aOR=1.04; 95%CI: 1.01-1.07). Compared with normal weight, obesity type I, obesity type II and obesity type III was associated with a greater likelihood of hospitalization compared with outpatient cases (aOR=1.85, 95%CI: 1.05-3.26; aOR=5.24, 95%CI: 1.94-14.15 and aOR=44.38, 95%CI: 4.47-440.5). Compared with normal weight, obesity type II and obesity type III was associated with a greater likelihood of hospitalization compared with outpatient controls (aOR=4.37, 95%CI: 1.79-10.69 and aOR=4.95, 95%CI: 1.45-16.87). In persons without influenza vaccination, all categories of BMI≥30kg/m(2) were associated with a greater likelihood of hospitalization compared with normal weight in both outpatient cases and outpatient controls. The PAF of hospitalization by influenza due to BMI ranged from 21.9% to 8.5%; in the case of unvaccinated against influenza between 20.5% to 16.9%. CONCLUSION: A high BMI is associated with an increased risk of hospitalization due to influenza. High percentage of hospital admissions are attributable to their BMI, especially in non vaccinated.

Social factors related to the clinical severity of influenza cases in Spain during the A (H1N1) 2009 virus pandemic.

BACKGROUND: During the 2009 influenza pandemic, a change in the type of patients most often affected by influenza was observed. The objective of this study was to assess the role of individual and social determinants in hospitalizations due to influenza A (H1N1) 2009 infection. METHODS: We studied hospitalized patients (cases) and outpatients (controls) with confirmed influenza A (H1N1) 2009 infection. A standardized questionnaire was used to collect data. Variables that might be related to the hospitalization of influenza cases were compared by estimation of the odds ratio (OR) and 95% confidence intervals (CI) and the variables entered into binomial logistic regression models. RESULTS: Hospitalization due to pandemic A (H1N1) 2009 influenza virus infections was associated with non-Caucasian ethnicity (OR: 2.18, 95% CI 1.17 - 4.08), overcrowding (OR: 2.84, 95% CI 1.20 - 6.72), comorbidity and the lack of previous preventive information (OR: 2.69, 95% CI: 1.50 - 4.83). Secondary or higher education was associated with a lower risk of hospitalization (OR 0.56, 95% CI: 0.36 - 0.87) CONCLUSIONS: In addition to individual factors such as comorbidity, other factors such as educational level, ethnicity or overcrowding were associated with hospitalization due to A (H1N1) 2009 influenza virus infections.