Population Studies

In the laboratory studies of the LE described previously patients were selected on the basis of neurologic complaints. Although these types of studies have been helpful in understanding the nature and severity of neurologic deficits in Lyme disease, they tell us little about the prevalence of these symptoms. Nancy Shadick and colleagues studied the prevalence of persistent neurologic symptoms in a sample of un-selected patients with a history of Lyme disease in Ipswich, Massachusetts, a community endemic for Lyme disease. These investigators initially studied 38 people who met CDC criteria for previous Lyme disease and 43 people who did not. There was a slight but statistically significantly difference between groups on the CVLT, with the Lyme disease group performing more poorly. Twelve of the 38 Lyme patients scored two or more standard deviations below mean on the word list test, compared to only 5 of the 43 controls. Patients with residual symptoms, neurologic and musculoskeletal, had longer duration of disease prior to treatment. These findings suggested that a small percentage of patients with previous Lyme disease may have permanent learning and memory deficits, albeit subtle. In a larger subsequent study on Nantucket, another community highly endemic for Lyme disease, these investigators compared 186 people with prior Lyme disease to 167 healthy controls using similar measures including the CVLT. Patients were studied an average of 6 years after infection. Although the patient group reported a higher incidence of nonspecific symptoms, including fatigue, difficulty sleeping, memory impairment, and poor concentration, there were no significant differences between groups on any of the objective tests of memory and concentration. At least two other population studies produced similar findings—namely, that the prevalence of objective measures of LE in previously infected patients who were treated for Lyme disese is very low. Thus, although patients previously infected with Lyme disease may report more neurologic symptoms than never infected controls, there is little evidence of any objective deficits. The relationship between reports of perceived memory dysfunction and performance on memory tests is discussed later.

Understanding And Treating Autism

Understanding And Treating Autism

Whenever a doctor informs the parents that their child is suffering with Autism, the first & foremost question that is thrown over him is - How did it happen? How did my child get this disease? Well, there is no definite answer to what are the exact causes of Autism.

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