Higher rates of invasive pneumococcal disease in children with asthma, diabetes
Asthma and diabetes are associated with increased rates of invasive pneumococcal disease and all-cause pneumonia across all age groups including older children, adolescents and young adults, according to data presented here during IDWeek2012.
"Patients with asthma and diabetes demonstrate increased risk of pneumococcal disease, which increases with disease severity," Stephen I. Pelton, MD, from the department of pediatric infectious diseases at Boston University Schools of Medicine and Public Health, said. "The presence of multiple at-risk conditions amplifies the risk of pneumococcal disease."
Pelton and colleagues conducted the retrospective cohort study utilizing health care claims data during 2007-2010 from two electronic databases that included 25 million people and 70 million person/years. The study population included patients ages 5 years and older who were enrolled in a large health plan during the 4-year study.
The study was designed to estimate pneumococcal disease incidence in patients aged 5 years and older with and without underlying co-morbidities. In addition, to estimate the relative risk of pneumococcal disease in patients aged 5 years and older with at-risk conditions, specifically diabetes and asthma, and high-risk conditions, compared with a control group of age-matched healthy patients.
The patients were categorized into three groups: 1) healthy, ie, no evidence of an at-risk for high-risk condition; 2) at-risk, ie, having chronic heart or lung disease, chronic liver disease, alcoholism, smoking, neuromuscular disorders, prematurity, small gestational age, asthma or diabetes; and 3) traditional high-risk conditions as reported by the US Public Health Service.
"Patients with asthma were further separated into mild, moderate or severe categories, and patients with diabetes were further categorized into insulin-dependent or not," Pelton said during his presentation.
Episodes of invasive pneumococcal disease (IPD) and all-cause pneumonia (PNE) were identified using IPD and PNE diagnosis codes. Among the 61.9 million person-years of observation, rates of IPD and PNE were consistently higher among persons with asthma and diabetes compared with persons without these conditions, Pelton said.
"The risk of both IPD and all-cause pneumonia is increased in patients with at-risk and high-risk conditions across all age groups," Pelton said. "Relative to healthy patients, the increased risk in patients with high-risk conditions compared to patients with at-risk conditions diminishes with age."
Pelton added that all-cause non-bacteremia pneumonia remains an important public health problem, which is further increased in patients with risk conditions. "However, the proportion of all-cause non-baceremic pneumonia that is pneumococcal disease is unknown and may vary across age or risk groups," he said.
One limitation of the study, according to Pelton, is that there is a potential for misclassification of pneumococcal disease because the data is taken from medical claims and the investigators were unable to review medical charts.