HEART FAILURE RATES INCREASE DURING WINTER

The incidence of myocardial infarction (MI) and sudden death increases during the winter months. The reason for this may be the body’s physiologic reaction to cold temperatures coupled with an increased incidence of seasonal respiratory infections, especially influenza. These factors could also lead to higher rates of hospitalization for and death from heart failure (HF).

To study the possibility of such a seasonal increase in hospitalizations and deaths due to HF, Stewart et al used the Scottish Morbidity Record to track all hospital discharges with a diagnosis of congestive HF or left HF/acute pulmonary edema for each calendar month between 1990 and 1996. The number of HF deaths in this same population was identified from 1990 to 1997.

The investigators found that the number and rate of hospitalizations for HF was markedly higher in the winter than summer. In both men and women, the greatest seasonal variation in hospitalization occurred in those 75 or older. The number of concomitant diagnoses of respiratory disease or acute MI also increased during the winter.

A strong seasonal variation in mortality was also noted (Figure 1). The number of men who died in the Decembers between 1990 and 1997 was 16% greater than average; in women, the number of deaths in December was 21% greater than average. The poorer long-term survival in winter suggests that those with more severe HF may be prone to winter exacerbations.

In light of these observations, Stewart et al strongly recommend increased vigilance of patients with HF during the winter months and immunization with pneumococcal and influenza vaccines.

Stewart S, McIntyre K, Capewell S, McMurray JJV. Heart failure in a cold climate: seasonal variation in heart failure–related morbidity and mortality. J Am Coll Cardiol. 2002;39:760-766.

Figure 1 Seasonal Variations on Deaths From Heart Failure

Adapted from Stewart et al. J Am Coll Cardiol. 2002.

CT SCANS NOT REFLECTIVE OF SINUSITIS SYMPTOMS

The diagnosis of sinusitis is made based on patient history, symptoms of facial pain or headache, and physical findings such as tenderness to percussion and the presence of purulent nasal discharge. The test routinely used to confirm sinusitis and plan sinus surgery is computed tomography (CT).

Mudgil et al undertook a prospective study to determine the correlation between CT findings and patient symptoms of facial pain and/or headache. Two hundred patients with a clinical diagnosis of sinusitis were referred for CT imaging. Patients completed a questionnaire in which they identified the level of sinus pain; its location and duration; and whether they used allergy medication, smoked, had pets, or suffered seasonal variations in symptoms. CT scans were then evaluated for air/fluid level, mucosal thickening, bony reaction, and mucus retention cysts.

The study found no statistically significant relationship between pain symptoms and findings on CT. A total of 182 patients had abnormal CT scans and a mean of 5.45 pain sites; of the 18 patients with normal CT scans, 16 reported a mean of 5.88 pain sites. Additionally, no relationship existed between the site of a patient’s most severe pain and CT findings. The diagnosis and management of sinusitis depend on clinical presentation, but symptoms of pain alone may not be enough to make a diagnosis. According to the investigators, CT is of limited value in a patient who has facial pain or headache but otherwise a low clinical suspicion of sinusitis.

Mudgil SP, Wise SW, Hopper KD, et al. Correlation between presumed sinusitis-induced pain and paranasal sinus computed tomographic findings. Ann Allergy Asthma Immunol. 2002;88:223-226.

FINE AIR PARTICULATE LINKED TO HEART DISEASE AND LUNG CANCER

In 1997, the Environmental Protection Agency imposed air-quality limits on fine particles measuring less than 2.5 µm in diameter (PM2.5). Most research has focused on short-term exposure, but several studies indicate that long-term exposure to fine particulate air pollution may have more important adverse health consequences. Pope et al analyzed data from the Cancer Prevention Study II (CPS-II), along with available air pollution data, to determine the effects of long-term exposure to fine particulate air pollution.

The CPS-II is an ongoing, prospective mortality study that surveyed about 1.2 million adults in 1982 to obtain demographic information including age, sex, weight, height, smoking history, alcohol use, occupational exposures, diet, and education. In 1984, 1986, and 1988, vital status of the study participants was recorded.

Pope and colleagues focused on about 500,000 CPS-II participants who lived in metropolitan areas with available pollution data. Nevertheless, the authors found that high measurements of PM2.5 were associated with all-cause mortality, as well as with deaths specifically from cardiopulmonary disease or lung-cancer mortality, but not with deaths from other specific causes. This association was still present after the analysis was controlled for cigarette smoking and other risk factors. Sulfur oxide pollution, however, was significantly associated with mortality from other causes.

Each 10-µg/m3 increase in long-term PM2.5 concentrations was associated with approximately 4%, 6%, and 8% increases in the risk of all-cause, cardiopulmonary, and lung-cancer mortality, respectively. When stratified by smoking status, the effect of pollution on cardiopulmonary and lung-cancer mortality was greater among nonsmokers than among current or former smokers.

The investigators concluded that long-term exposure to fine particulate air pollution is an important risk factor for cardiopulmonary and lung-cancer mortality.

Pope CA III, Burnett RT, Thun MJ, et al. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution. JAMA. 2002;287:1132-1141.

SUSCEPTIBILITY TESTING TO FLUOROQUINOLONES RECOMMENDED

In the wake of increased resistance of Streptococcus pneumoniae to ß-lactam antibiotics, fluoroquinolones have been recommended for use in patients with community-acquired pneumonia caused by multidrug-resistant strains. However, antimicrobial resistance to these agents is also developing. Davidson et al reported on four patients with pneumococcal pneumonia in whom treatment with oral levofloxacin failed.

In all four patients, the organisms were resistant to levofloxacin. In at least two of the cases, initially susceptible organisms became resistant during treatment.

With ß-lactam, tetracycline, and macrolide antibiotics, pneumococcal resistance usually is caused by the acquisition of a resistance gene before therapy. With fluoroquinolones, however, resistance or reduced susceptibility can also develop during the course of therapy or as a result of previous fluoroquinolone use.

Davidson et al suggest that routine testing of pneumococci for fluoroquinolone susceptibility be performed to identify patients infected with resistant strains. Physicians should also keep in mind that resistance may develop during therapy. In addition, the researchers recommend that recent fluoroquinolone use should be considered a contraindication to administration of another fluoroquinolone for empiric treatment of community-acquired pneumonia. They acknowledge, however, that no position papers currently support their recommendation.

Davidson R, Cavalcanti R, Brunton JL, et al. Resistance to levofloxacin and failure of treatment of pneumococcal pneumonia. N Engl J Med. 2002;346:747-750.

OTC COUGH PRODUCTS QUESTIONED

Health professionals often recommend over-the-counter (OTC) cough medicines for the treatment of acute cough. Evidence of these medicines’ effectiveness is not conclusive, however. Schroeder and Fahey conducted a review of published studies to determine whether OTC cough medicines are effective in treating cough in adults with upper respiratory tract infections.

Fifteen trials with a total of 2,166 patients were evaluated. The trials tested OTC cough suppressants, expectorants, or antihistamine/decongestant combinations. Outcomes included frequency and severity of cough and, in 10 trials, adverse effects.

The studies failed to demonstrate any consistent difference between treatment and control groups. In nine of 15 trials, active treatment was no more effective than placebo, and according to the investigators, the positive results in the remaining trials were of questionable relevance. The authors concluded that OTC cough medicines should not be recommended as a matter of course for cough associated with upper-respiratory-tract infections.

Schroeder K, Fahey T. Systematic review of randomised controlled trials of over the counter cough medicines for acute cough in adults. BMJ. 2002;324:329-331.