Relationship between oral Candida species and risk factors with reference to drugs with xerostomic side effects among institutionalised elderly in Aichi Pref., Japan.

Objective: To clarify the relationship between Candida carriage and drugs which have reported xerostomic side effects in the elderly.

Design: Cross-sectional study. Setting Two long-term care facilities in Aichi Pref., Japan.

Participants: Eight men and 63 women with a mean age of 86 years (range 62 to 95 years) with at least some of their natural teeth.

Method: Oral examination by dentists, microbiological test by microbiologists, questionnaire interviews, and data obtained from medical files. The Candida species (CFU) was adopted as an objective variable with risk indicators being age, number of teeth, saliva flow rate, denture wearing, xerostomic drugs, activities of daily living (ADL), frequency of brushing and type of meals.

Results: Bivariate analysis confirmed that participants with a higher number of Candida species (CFU) fell into the following categories: denture wearing (p < 0.05), older age (p < 0.05), xerostomic drugs (p < 0.10), more teeth, poor ADL, soft/liquid meals, and brushing once a day. This was in contrast to the categories of no denture wearing, younger age, no xerostomic drugs, fewer teeth, good ADL, normal meals, and brushing two or more times a day, in that order of significant probability on an ascending scale. A multiple logistics regression model confirmed that the variables of older age (80 years and over) and more teeth (six or more) had statistically significant (p < 0.05) effects on the number of Candida species present (CFU). Xerostomic drugs and the other variables had no significant effect.

Conclusion: Older age and more teeth had a significant effect on the number of oral Candida species in the elderly. The results of this study did not support a role of those drugs as a risk indicator for oral Candida carriage. Larger trials are needed to assess the effect of drugs on the presence of oral Candida.