Maintenance laxative usage was associated with apparent stemming of the temporal increase in rigidity in PD, adding to indicative evidence of a continuing role of gastrointestinal dysbiosis in pathogenesis.
The immediate therapeutic implication is that maintenance laxatives are disease-modifying in PD. The aetio-pathogenic implication is that change in the gut environment has a continuing and profound, but at least in part reversible, adverse effect.
Source: Augustin, A. D., Charlett, A., Weller, C., Dobbs, S. M., Taylor, D., Bjarnason, I., and Dobbs, R. J. (2016) Quantifying rigidity of Parkinson’s disease in relation to laxative treatment: a service evaluation. Br J Clin Pharmacol, 82: 441–450. doi: 10.1111/bcp.12967.