The "protective" influence of cigarette smoking on Alzheimer's and Parkinson's diseases. Quagmire or opportunity for neuroepidemiology?

Neurol Clin. 1996 May;14(2):353-8. doi: 10.1016/s0733-8619(05)70261-9.


The negative association between smoking and both Alzheimer's (AD) and Parkinson's (PD) diseases is a consistent epidemiologic finding. This observation has prompted many investigators to conclude that cigarette smoking must be "biologically protective" against AD and PD. Rather than suggesting some as-yet-undefined pathogenetic clue, however, this negative association more likely is indicative of the under-appreciated influence of differential survival in epidemiologic studies.

Publication types

  • Review

MeSH terms

  • Adult
  • Age of Onset
  • Aged
  • Alzheimer Disease / epidemiology*
  • Alzheimer Disease / prevention & control
  • Causality
  • Data Interpretation, Statistical
  • Disease Susceptibility / epidemiology
  • Female
  • Genetic Predisposition to Disease
  • Genetics, Population
  • Humans
  • Male
  • Middle Aged
  • Neuroprotective Agents / adverse effects
  • Parkinson Disease / epidemiology*
  • Parkinson Disease / prevention & control
  • Selection Bias
  • Smoking / adverse effects
  • Smoking / epidemiology*
  • Smoking / genetics
  • Survival Rate


  • Neuroprotective Agents