Occurrence and risk factors of oral candidiasis treated with oral antifungals in seniors using inhaled steroids.

Oral candidiasis (OC) is a frequent side effect of inhaled corticosteroids (iCSTs). This study estimated occurrence and significance of risk factors of OC treated with antifungals in users of iCSTs under conditions of normal use. This retrospective analysis used data drawn from drug insurance plan records in Quebec, Canada. The sample contained 27,000 seniors using anti-asthma medications during 1990. Three years of data (1989-1991) were searched for use of oral antifungals concurrent with exposure to iCSTs. A case-control study examined factors leading to increased probability of first incidence of OC in new users of iCSTs. Three-year occurrence for OC was 7%. Increased risk for a first occurrence of OC was significantly associated with higher doses of iCST, increased length of iCST exposure, use of antibiotics, use of oral steroids, having three or more prescribers, a history of use of both high and low strengths of iCST, and concurrent use of oral steroids and diabetes medications. The occurrence of OC is relatively high. Knowledge of factors leading to increased risk could facilitate the targetting of patients who need timely intervention, under conditions of normal use.