Introduction: Clinical manifestations of influenza range from relatively mild and self-limiting respiratory infections to severe clinical manifestations with significant morbidity and mortality. The awareness of predictive indicators for the lethal outcome of influenza is of particular significance in making timely and exact decision for adequate treatment. The aim of this study was to identify the factors in patients with a severe form of influenza, resulting in lethal outcome. Materials and methods:The investigation was a prospective group comparison conducted at the University Clinic for Infectious Diseases in Skopje, R. Macedonia in the period from January 01, 2012 to January 01, 2015. The study included adult patients with a severe form of influenza who were further categorized into a group of either survived patients or a group of deceased patients. Demographic, clinical and biochemical data were noted in all patients included in the study on admission. The variables of the univariate analysis that showed a significant difference in terms of the outcome were used for creating multivariate logistic and regression analysis of the outcome as dependent factors. The independent predictors for lethal outcome in severe cases of influenza were identified by using logistic regression. Results: The study included 87 patients with a severe form of clinical and laboratory confirmed influenza. The patients were divided in two groups: survived (n = 75) and deceased (n = 75). The overall mortality was 13.79%. Multivariate analysis conducted on admission to hospital identified cardiovascular comorbid diseases (p = 0.014), urea values higher than 8.3 U/L (p = 0.045) and SAPS score (p = 0.048) as independent predictors of the outcome in patients with severe form of influenza. Influenza patients with cardiovascular diseases had 2.024 times greater risk of death from influenza in comparison to the patients having influenza without history of such a disease (OR = 2.024 95% CI 1.842-17.337). Patients with serum urea values higher than 8.3 U/L had 1.89 times higher chance of death compared to patients with normal values (OR = 1.89 95% CI 1.091-11.432). The increase of the SAPS score in one point increased the chance of death in patients with influenza by 1.2% (OR = 1.12 95% CI 1.01-2.976). The ROC analysis indicated that cardiovascular diseases, increased urea values and SAPS score in combination act as a good prognostic model for the fatal outcome. The global authenticity of this predictive model to foresee lethal outcome amounts to 80%, sensitivity being 82%, and specificity 70%. Conclusion: Cardiovascular diseases, increased values of urea over 8.3 mmol/l and SAPS score are independent predictive indicators for lethal outcome in severe influenza. Early identification of the outcome predictors in patients with severe influenza will allow implementation of adequate medical treatment and will contribute to decreasing of mortality in patients with severe form of influenza.

Introduction. The risk factors associated with the progression of a severe clinical form of seasonal influenza are of a particular importance in developing a current and accurate decision in terms of treatment options. Aim. The aim of the study was to identify the specific factors associated with a severe form of seasonal influenza. Method. The study was conducted as a prospective, group comparison at the University Clinic for Infectious Diseases in Skopje, Macedonia, during the period of January 01, 2012, until January 01, 2015. This study analyzed 122 adult patients, who were clinically-confirmed to be infected with seasonal influenza by laboratory analyses and other necessary tests. These patients were grouped into two categories: patients with a mild form of seasonal influenza, and patients with a severe form of seasonal influenza. Furthermore, the demographic, clinical, and biochemical results obtained were analyzed. The variables in the univariable analysis which were significantly associated with a severe form of seasonal influenza were included in the multivariable logistic regression analysis in order to extract and determine the independent predicttors of a severe form of seasonal influenza. Results. The multivariable analysis yielded cardiovascular diseases (p=0.01), dyspnea (p=0.001), tachypneа >20 respiration/ minute (p=0.005), values of LDH greater than 618 U/L (p=0.048) and SAPS 2score (p=0.031) as independent variables which predict the severity of the illness. The area under the ROC curve [0.826 (95% CI)] suggests that the probability of a severe form of influenza was82.6%. The global accuracy for this model to predict a severe form of influenza was 81.1%, with the sensitivity being 88.5%, and the specificity 72.9%. Conclusion. Cardiovascular diseases, dyspnea, tachypnea, elevated levels of LDH and SAPS 2 score are independent predictive indicators for severe influenza. Early identification of these indicators will allow implementation of adequate medical intervention which will in turn reduce mortality rates.

Elderly patients and patients with different comorbid conditions are at a higher risk of developing severe clinical course and lethal influenza outcome. The aim of this study was to define comorbid conditions in patients with a severe form of seasonal influenza, and to define their influence on lethal outcome. The study was a prospective, group comparison and was conducted at the University Clinic for Infectious Diseases in Skopje, Macedonia, during the period of January 01, 2012 to January 01, 2015. The study included 87 adult patients with a severe form of seasonal influenza, who were further categorized in to a group of either survived patients (n=75) and a group of deceased patients (n=12). Demographic parameters of the patients, as well as any comorbid medical conditions, such as cardiovascular disease, chronic lung disease, neurological diseases, weakened immune system, endocrine disorders, kidney disorders, liver disorders, pregnancy, overweight were noted upon admission in the hospital. The variables of the univariate analysis that showed a significant difference in terms of the outcome were used for creating multivariate logistic and regression analysis to identify independent predictors for lethal outcome in severe cases of influenza. Multivariate analysis identified cardiovascular comorbid diseases (p=0.014), as an independent predictor of the outcome in patients with severe form of seasonal influenza. Influenza patients with cardiovascular diseases had 2.024 times greater risk of death from influenza in comparison to patients having influenza without a history of such a disease (OR=2.024 95% CI 1.842-17.337).