Severe Pneumonia in the Elderly: Risks, Treatment, and Prevention

, Winthrop University Hospital, Mineola, NY


Medscape General Medicine. 1998;1(3) 

In This Article

Pneumonia Prevention in the Elderly

Innoculations. Influenza infection can cause significant morbidity and mortality, particularly in the elderly, and predisposes individuals to bacterial pneumonia, especially due to S pneumoniae,S aureus, or gram-negative enteric pathogens. Several studies[46,47,48] have documented the clinical and economic effects of influenza vaccination. Influenza vaccination programs can reduce hospitalizations and mortality in the elderly, and are therefore cost-effective strategies to implement.[46] Studies[8,46,47,48,49,50,51] have documented a 30% to 50% reduction in hospitalizations and a decrease in mortality from 39% to 54% among high-risk patients (age > 65 years, chronic medical illness, nursing home residents, and/or patients with HIV infection).

Because pneumococcal species are the most common inciting pneumonia pathogens in the elderly, the development and utilization of the pneumococcal vaccine was a major public health milestone. The current vaccine is designed to elicit protective antibodies against 23 of 83 known capsular serotypes of S pneumoniae.[49,52] These serotypes cause 90% of the invasive pneumococcal disease and include most penicillin resistant strains. The vaccine can be administered either subcutaneously or intramuscularly and only minor, self-limited reactions occur in 50% of recipients.[53] Although the initial recommendation was for a single lifetime vaccination, it is now recommended that patients be re-vaccinated every six years to enhance waning immunity. Currently the vaccine is recommended for the elderly and those patients presenting with asplenia, chronic respiratory disease, cardiac dysfunction, renal disease, diabetes mellitus, and HIV infection. Although the effectiveness is clear, vaccination rates across the US have been low, with only one-third of eligible elderly patients vaccinated in 1989, and one half in 1993.[54] Intensive efforts are underway to improve compliance.

Who benefits most from the vaccine? There is some controversy related to the use of pneumococcal vaccines. In a recent meta-analysis[52] examining the effectiveness of pneumococcal vaccination, patients were divided into low and high risk groups to evaluate benefit from a vaccination program. The results of this analysis demonstrated that pneumococcal pneumonia was more likely to be prevented in low-risk patients (those without risk factors for pneumonia) than in high-risk patients with an overall efficacy estimated at 50%.[52]

Nutritional therapy. There is significant evidence implicating malnutrition as a risk factor for pneumonia in older patients.[55,56,57,58] However, evaluating benefits of nutritional intervention are difficult to study. Both low serum albumin and risk of aspiration have been identified as contributory factors for lower respiratory tract infections in elderly individuals.[56,59,60] Recently, it was shown that in elderly patients with pneumonia, the addition of 0.5L nutritional supplement per day resulted in better functional status at 3 months.[57] While nutritional surveillance in elderly at risk patients has been suggested, there is no data to support its routine implementation. In another preliminary study evaluating the effects of nutritional supplements in the elderly,[61] patients with bronchitis or pneumonia were randomly assigned to placebo or vitamin C.[58] The investigators reported that those elderly patients who received vitamin supplementation had better clinical scores than those elderly patients who received placebo. Alternatively, other investigators have suggested malnutrition was less important than chronic illness as an independent risk factor for developing pneumonia. The role of nutritional interventions as a preventive strategy remains uncertain.