Neurological and neuromuscular diseases raise risk of complications from flu

As another flu season approaches, patients with neurological and neuromuscular disease are especially vulnerable to respiratory failure caused by influenza.

Researchers from The Children's Hospital of Philadelphia identified this high-risk group of patients, who have recently been added to the list of groups for whom the federal government recommends receiving annual influenza vaccine.

The research is published in the November 2 issue of the Journal of the American Medical Association. The neurological and neuromuscular diseases studied include cerebral palsy, hydrocephalus, muscular dystrophies, spinal muscular atrophy and seizure disorders.

"Our findings support the recent decision of the Advisory Committee on Immunization Practices [ACIP] to add neurological and neuromuscular disease to the list of chronic conditions that warrant annual influenza vaccination," said study leader Ron Keren, M.D., M.P.H., a pediatrician at The Children's Hospital of Philadelphia. "We hope this news will reach parents of children with these diseases, as well as health care providers."

The ACIP, an expert panel that advises the CDC on national vaccine practice, had previously designated nine groups of chronic medical conditions for which a flu shot is recommended. Among those conditions are asthma, chronic lung disease, heart disease, disorders of hemoglobin such as sickle cell disease, and chronic kidney disease. The Children's Hospital study considered all those conditions, in addition to neurological and neuromuscular disease, gastroesophageal reflux disease, and history of prematurity.

The researchers studied the hospital records for 745 children hospitalized at Children's Hospital for influenza during the 2000 to 2004 flu seasons. Of that total, 32 children (4 percent) developed respiratory failure and needed mechanical ventilation. Of all the chronic conditions studied, children with neurological and neuromuscular disease were at the highest risk of respiratory failure, followed by chronic pulmonary disease other than asthma, and cardiac disease.

The link between neurological disease and respiratory failure among children with flu was a new finding, but not surprising, said Dr. Keren. "Children with neurological and neuromuscular disease often have diminished pulmonary function and ability to handle secretions at baseline, and therefore are more vulnerable to respiratory complications of influenza infection."