Long-term outcomes of 217 botulism cases in the Republic of Georgia

Abstract

Background: The acute paralytic syndrome of botulism has been well-described; however, little is known about its long-term consequences.

Methods: We conducted a case-control study in the Republic of Georgia to evaluate the health of patients > or =6 months after they had experienced an episode of botulism. Case patients were selected on the basis of who had had a clinical diagnosis of foodborne botulism reported to the national surveillance system from 1998 through 2003. Three control subjects were randomly selected from each patient's community.

Results: We located 217 patients who had had botulism from surveillance records, with a median time since onset of illness of 4.3 years. The median age was 37 years, and 49% of the patients were female, similar to the control subjects. Most of the patients (68%) had acquired botulism from home-conserved vegetables (probably containing toxin type B), 15% had been hospitalized for >1 month, and 25% had required mechanical ventilation. Six patients died. Of the remaining 211 patients, 68% reported having worse health at the time of the interview than 6 years before the interview, compared with 17% of 656 control subjects (matched odds ratio, 17.6; 95% confidence interval, 10.9-28.4). Overall, 49% of the patients reported their current health as "fair" or "poor," versus 25% of the control subjects (odds ratio, 5.0; 95% confidence interval, 3.2-7.6). Patients were more likely than control subjects to report fatigue, weakness, dizziness, dry mouth, and difficulty lifting objects (P<.05, for each). Patients were more likely than control subjects to report difficulty breathing caused by moderate exertion (P<.001) but not by minimal exertion or at rest. Patients were also more likely to report being limited in vigorous activities, walking 3 blocks, and climbing 3 flights of stairs (P<.05, for each). Finally, patients reported feeling significantly worse than control subjects for 6 of 11 questions regarding psychosocial well-being (P<.05, for each). In a multivariable model involving patients who had had botulism, mechanical ventilation during acute illness, older age, and region of residence independently predicted worse health.

Conclusions: Several years after acute botulism, patients reported significant health, functional, and psychosocial limitations that are likely to be consequences of the illness.