Dietary determinants of a non-progressive spastic paraparesis (Konzo): a case-referent study in a high incidence area of Zaire.

BACKGROUND

Konzo is an upper motor neuron disease in Africa, characterized by an abrupt onset of a permanent but non-progressive spastic paraparesis. It is named after the local designation in the first report from Zaire. Konzo has been attributed to a metabolic insult from the combined effect of high cyanide and low sulphur intake from several weeks of exclusive consumption of insufficiently processed bitter cassava roots.

METHODS

The association between insufficient soaking of cassava roots and konzo is assessed in a matched case-referent study with multivariate conditional logistic regression including 57 case-referent pairs from a rural high incidence community of Zaire.

RESULTS

In the multivariate analysis short processing of cassava in the form of only 2 nights soaking yielded an odds ratio of 11.0 (95% confidence interval 1.7-73) when controlling for poverty-related factors and diet. We also show a dose-response relationship for insufficient cassava soaking, both unadjusted and adjusted for potential confounders.

CONCLUSIONS

This study supports a causal relationship between insufficient processing of bitter cassava and konzo.