Incidence and Risk of Pneumococcal Pneumonia in Adults with Distinct Underlying Medical Conditions: A Population-Based Study

PURPOSE

This study investigated the incidence of pneumococcal pneumonia requiring hospitalisation among middle-aged and older adults with and without specific underlying medical conditions, evaluating the influence of these conditions in the risk of developing pneumonia.

METHODS

Population-based prospective cohort study included 2,025,730 individuals ≥ 50 years around Catalonia, Spain. The Catalonian information system for the development of research in primary care (SIDIAP) was used to establish baseline characteristics of the cohort (comorbidities and underlying medical conditions). Hospitalisations from pneumococcal pneumonia occurred among cohort members between 01/01/2015 and 31/12/2015 were collected from hospital discharge codes of 68 reference Catalonian hospitals. Cox regression was used to estimate the association between baseline conditions and the risk of developing pneumonia.

RESULTS

Global incidence rate (IR) of hospitalised pneumococcal pneumonia was 82.8 cases per 100,000 persons-year. Maximum IRs (per 100,000 persons-year) emerged among persons with haematological neoplasia (837.4), immunodeficiency (709.2), HIV infection (474.7), severe renal disease (407.5) and chronic pulmonary disease (305.7). In the multivariable analyses, apart from increasing age, HIV infection (hazard ratio [HR] 6.78), haematological neoplasia (HR 6.30), prior all-cause pneumonia (HR 5.27), immunodeficiency (HR 4.57) and chronic pulmonary disease (HR 2.89) were the conditions most strongly associated with an increasing risk. Pneumococcal vaccination did not emerge associated with a reduced risk in our study population (nor PPsV23 neither PCV13).

CONCLUSION

Old age, immunocompromising conditions and chronic pulmonary/respiratory disease are major risk factors for pneumococcal pneumonia in adults. Our data underline the need for better prevention strategies in these persons.

Prevalence of high, medium and low-risk medical conditions for pneumococcal vaccination in Catalonian middle-aged and older adults: a population-based study

Background

Updated population-based data on the frequency and distribution of risk factors for pneumococcal disease is scarce. This study investigated the prevalence of distinct comorbidities and underlying risk conditions related to an increasing risk of pneumococcal disease among Catalonian middle-aged and older adults.

Methods

Cross-sectional population-based study including 2,033,465 individuals aged 50 years or older registered at 01/01/2015 in the Catalonian Health Institute (Catalonia, Spain). The clinical research database of the Information System for the Development of Research in Primary Care (SIDIAP database) was used to identify high-risk (asplenia and/or immunocompromising conditions) and other increased-risk conditions (chronic pulmonary, cardiac or liver disease, diabetes mellitus, alcoholism and/or smoking) among study subjects.

Results

Globally, 980,310 (48.2%) of the 2,033,465 study population had at least one risk condition of suffering pneumococcal disease (55.4% in men vs 42.0% in women, p < 0.001; 41.7% in people 50–64 years vs 54.7% in persons 65 years or older, p < 0.001). An amount of 176,600 individuals (8.7%) had high-risk conditions (basically immunocompromising conditions). On the other hand, 803,710 persons (39.5%) had one or more other risk conditions. In fact, 212,255 (10.4%) had chronic pulmonary diseases, 248,377 (12.2%) cardiac disease, 41,734 (2.1%) liver disease, 341,535 (16.8%) diabetes mellitus, 58,781 (2.9%) alcoholism and 317,558 (15.6%) were smokers.

Conclusion

In our setting, approximately 50 % of overall persons 50 years or older may be considered at-risk population for pneumococcal disease (almost 10 % have high-risk conditions and 40 % have other risk conditions).

Incidence and risk conditions of ischemic stroke in older adults

OBJECTIVE

The objective of this study was to investigate incidence and mortality from ischemic stroke in older adults with specific underlying chronic conditions, evaluating the influence of these conditions in developing stroke.

MATERIALS & METHODS

Population-based cohort study involving 27,204 individuals ≥60 years old in Southern Catalonia, Spain. All cases of hospitalization from ischemic stroke (confirmed by neuro-imaging) were collected from 01/12/2008 until 30/11/2011. Incidence rates and 30-day mortality were estimated according to age, sex, chronic illnesses, and underlying conditions. Multivariable Cox regression analysis was used to calculate Hazards Ratio (HR) and estimate the association between baseline conditions and risk of developing stroke.

RESULTS

Mean incidence rate reached 453 cases per 100,000 person-years. Maximum rates appeared among individuals with history of prior stroke (2926 per 100,000), atrial fibrillation (1815 per 100,000), coronary artery disease (1104 per 100,000), nursing-home residence (1014 per 100,000), and advanced age ≥80 years (1006 per 100,000). Thirty-day mortality was 13% overall, reaching 21% among patients over 80 years. Age [HR: 1.06; 95% confidence interval (CI): 1.04-1.07], history of prior stroke (HR: 5.08; 95% CI: 3.96-6.51), history of coronary artery disease (HR: 1.65; 95% CI: 1.21-2.25), atrial fibrillation (HR: 2.96; 95% CI: 2.30-3.81), diabetes mellitus (HR: 1.55; 95% CI: 1.23-1.95), and smoking (HR: 1.64; 95% CI: 1.15-2.34) emerged independently associated with an increased risk of ischemic stroke.

CONCLUSION

Incidence and mortality from ischemic stroke remains considerable. Apart from age and history of atherosclerosis (prior stroke or coronary artery disease), atrial fibrillation, diabetes, and smoking were the underlying conditions most strongly associated with an increased risk.

Epidemiology of Streptococcus pneumoniae causing acute otitis media among children in Southern Catalonia throughout 2007-2013: Incidence, serotype distribution and vaccine's effectiveness

OBJECTIVE

This study investigated incidence and serotype distribution of Streptococcus pneumoniae causing acute otitis media (AOM) in Catalonian children, evaluating vaccination effectiveness in the current era of extended valency pneumococcal conjugate vaccines (PCVs).

METHODS

Population-based surveillance study that included all AOM cases with isolation of pneumococcus (from otic fluids/otorrea) identified among children ≤14 years in the region of Tarragona (Southern Catalonia, Spain) from 01/01/2007 to 31/12/2013. Prevalence of infections caused by serotypes covered by the different PCVs formulations were calculated for the periods before and after 30/06/2010 (date of PCV7/PCV13 replacement). The indirect cohort method was used to estimate PCV7/13 effectiveness against vaccine-type infections.

RESULTS

A total of 78 children with a pneumococcal AOM were identified across study period, which meant an incidence rate of 23 cases per 100,000 population-year. Thirty-six cases (46.2%) occurred within the late PCV7 era and 42 cases (53.8%) during the early PCV13 era. Overall, the most common serotypes were type 19A (21.7%), type 3 (13.3%) and type 15B (6.7%). Prevalence of cases caused by serotypes included in PCV7 did not substantially change between the first and the second study period (from 10.3% to 12.9%), whereas prevalence of cases caused by PCV13 serotypes showed a decreasing trend between both periods (from 65.5% to 48.4%). The aggregate PCV7/13 effectiveness against vaccine-type infections was 72% (95% confidence interval: -26 to 94).

CONCLUSION

Pneumococcal conjugate vaccination appears an acceptable preventive option to prevent pneumococcal AOM in infants. However, its serotype coverage and clinical effectiveness are not optimal.