Abstracts from Medical Literature for the Geriatrics Practitioner

Influenza Vaccination and Risk of Mortality in Adults with CAP

Influenza vaccination has been shown to reduce illness and all-cause mortality in vulnerable populations. The authors evaluated the impact of prior influenza vaccination on in-hospital mortaqlity and other health outcomes among hospitalized adults with community-acquired pneumonia (CAP). Consecutive individuals hospitalized with CAP during “influenza season” during November-April, 1999-2003, were identified. Among 17,393 adults, 1590 had a history of influenza vaccination in the current or most recent influenza season. The authors found that vaccine recipients were less likely to die in the hospital of any cause than individuals without vaccination (odds ratio [OR], 0.30; 95% confidence interval, 0.22-0.41). These effects remained significant after adjustment for the presence of comorbid illness and pneumococcal vaccination (adjusted OR for death, 0.61; 95% confidence interval, 0.43-0.87) and under widely varying assumptions about individuals with missing vaccination status. The authors concluded that influenza vaccination was associated with improved survival in hospitalized patients with CAP during influenza season. This observation, if confirmed by other studies, would represent an important additional benefit of enhanced influenza vaccine coverage. Spaude KA, Abrutyn E, Kirchner C, et al. Influenza vaccination and risk of mortality among adults hospitalized with community-acquired pneumonia. Arch Intern Med 2007;167:53-59.
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Prevention of CVD with Pravastatin in Japan

Evidence-based treatmentfor hypercholesterolemia in Japan has been hindered by lack of direct evidence in this population. The investigators’ aim was to assess whether evidence for treatment of statins derived from western populations could be extrapolated to the Japanese population. Patients with hypercholesterolemia (total cholesterol 5.69-6.98 mmol/L) and no history of coronary heart disease or stroke were randomly assigned to diet or diet plus 10-20 mg pravastatin daily. The primary endpoint was the first occurrence of coronary heart disease. 3966 patients were randomly assigned to the diet group and 3866 to the diet plus pravastatin group, with a mean follow-up of 5.3 years. Findings showed that at the end of the study, 471 and 522 patients had withdrawn, died, or been lost to follow-up in the diet and diet plus pravastatin groups, respectively. Mean total cholesterol was reduced by 2.1% (from 6.27 mmol/L to 6.13 mmol/L) and 11.5% (from 6.27 mmol/L to 5.55 mmol/L) and mean LDL cholesterol by 3.2% (from 4.05 mmol/L to 3.90 mmol/L) and 18.0% (from 4.05 mmol/L to 3.31 mmol/L) in the diet plus pravastatin group than in the diet alone group (66 events vs 101 events; HR 0.67, 95% confidence interval, 0.49-0.91; P = 0.01). There was no difference in the incidence of neoplasms or other serious adverse events between the two groups. The investigators concluded that treatment with a low dose of pravastatin reduced the risk of coronary heart disease in Japan by much the same amount as higher doses have shown in Europe and the United States. Nakamura H, Arakawa K Itakura H, et al, for the MEGA Study Group. Primary prevention of cardiovascular disease with pravastatin in Japan (MEGA Study): A prospective randomized controlled trial. Lancet 2006;368:1155-1163.
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Vitamin B₆, B₁₂, Folic Acid Supplementation and Cognitive Function

Despite their important role in cognitive function, the value of B vitamin supplementation is unknown. The authors did a systematic review of the effect of B₆, B₁₂, and folic acid supplementation through a literature search conducted in MEDLINE with supplemental articles from reviews and domain experts. Fourteen trials met their criteria, but most were of low quality or limited applicability. Approximately 50 different cognitive function tests were assessed. Three trials of vitamin B₆ and six of B₁₂ found no effect overall in a variety of doses, routes of administration, and populations. One of the three trials of folic acid found a benefit in cognitive function in people with cognitive impairment and low baseline serum folate levels. Six trials of combinations of the B vitamins all concluded that the interventions had no effect on cognitive function. Among three trials, those in the placebo arm had greater improvements in a small number of cognitive tests than participants receiving either folic acid or combination B vitamin supplements. The evidence was limited by a sparsity of studies, small sample size, heterogeneity in outcomes, and a lack of studies that evaluated symptoms or clinical outcomes. The authors concluded that the evidence does not yet provide adequate evidence of an effect of vitamin B₆ or B₁₂ or folic acid supplementation, alone or in combination, on cognitive function testing in people with either normal or impaired cognitive function. Balk EM, Raman G, Tatsioni A, et al. Vitamin B₆, B₁₂, and folic acid supplementation and cognitive function: A systematic review of randomized trials. Arch Intern Med 2007;167:21-30.
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PPI Therapy and Hip Fracture

Proton pump inhibitors may interfere with calciumabsorption through induction of hypochorhydria, but theymay also reduce bone resorption through inhibition of osteoclastic vacuolar proton pumps. The investigators in this study sought to determine the association between PPI therapy and risk of hip fracture. This nested case-control study was conducted using the General Practice Research Database (1987-2003), which contains information on patients in the United Kingdom. The study cohort consisted of users of PPI therapy and nonusers of acid suppression drugs who were older than age 50, including all patients with an incident hip fracture. There were 13,556 hip fracture cases and 135,386 controls. Results showed that the adjusted odds ratio for hip fracture associated with more than 1 year of PPI therapy was 1.44 (95% CI, 1.30-1.59). The risk of hip fracture was significantly increased among patients prescribed long-term, high-dose PPIs (AOR, 2.65; 95% CI, 1.80-3.90; P < .001). The strength of association increased with increasing duration of PPI therapy (AOR for 1 year, 1.22[95% CI, 1.15-1.30]; 2 years, 1.41 [95% CI, 1.28-1.56]; 3 years, 1.54 [95% CI, 1.37-1.73]; and 4 years, 1.59 [95% CI, 1.39-1.80; P< .001 for all comarisons). The investigators concluded that long-term PPI therapy, particularly at high doses, is associated with increased risk of hip fracture. Yang Y-X, Lewis JD, Epstein S, Metz D. Long-term proton pump inhibitor therapy and risk of hip fracture. JAMA 2006;206:2947-2953.