Objective: To determine the rates of various types of infections on an Alzheimer's special care unit (ASCU) compared with the rates found on traditional nursing home units. Because patients on the ASCUs are allowed to wander throughout the unit and typically come into contact with each other more frequently, we hypothesized that the rate of communicable infections such as upper respiratory infections are significantly higher than on other units where patients are more easily isolated when sick.
Methods: A 4-year retrospective case control study, 1990-1993.
Setting: A metropolitan long-term care skilled nursing facility. Three floors are traditional nursing care units (123 beds), and one floor is the ASCU (41 beds).
Primary outcome: Annual nosocomial infection rates per 10,000 patient days were measured for six types of infection during the 1990-1993 study period. Data were segregated by location of infection, either the traditional nursing units or the ASCU. In 1992, patients on the Alzheimer's unit were placed in smaller activity groups, and an education program for the control of infectious agents was provided to the unit's staff.
Results: The relative order of prevalence for the different infection types remained constant during the 4 years. The most common type of infection for all 4 years of the study period was urinary tract infection (UTI), followed by upper respiratory infection (URI), Lower respiratory tract infection (LRI), cutaneous infection, gastrointestinal (GI) infection, and eye infection. Of these various infections, only URI rates remained consistently higher on the ASCU versus the traditional nursing unit over the 4-year study period (in years 1990, 1991, and 1993; these differences were statistically significant, P < .05). In 1992, the year in which nursing interventions to curb the relatively high rates of URI on the ASCU took place, the rates of URI on the two unit types were not statistically different.
Conclusions: This study suggests that an inherent risk of ASCUs is an increased exposure to highly contagious infections such as upper respiratory infections. An intervention program effective in decreasing this risk to the level of traditional nursing units is proposed. A prospective study is needed to confirm these findings.