There were 10,586 home care clients in the HNHB health region who received an assessment during the January 1, 2018 to March 31, 2018 period (n = 10,586). The were no missing data, given that the RAI-HC is the basis for electronic medical records in the home care setting and assessment fields are mandatory [30]. The outcome variable, falls frequency in the last 90 days, was skewed to the right. Fifty-two per cent of the sample (n = 5,481) did not experience a fall, whereas 40% (n = 4,214) experienced one to three falls. Six per cent of the sample (n = 649) experienced four to eight falls, and two per cent of the sample (n = 242) experienced nine or more falls.
Description of population-based sample
Table 1 describes our population-based sample of home care clients in the HNHB health region. Home care clients were predominately female (n = 6,462, 61%), between the ages of 80-89 (n = 3,920, 37%) and were widowed (n = 4,363, 41%). Some home care clients had minimally impaired cognitive skills for daily decision-making (n = 2,228, 21%), but most had declines in activities of daily living (n = 6,915, 65%), used a walker or crutch for locomotion indoors (n = 4,804, 45%), and were unable to go up and down the stairs (n = 6,332, 60%). Over half of our sample took eight or more drugs (n = 6,744, 64%), and many experienced dizziness or lightheadedness (n = 2,795, 26%), edema (n = 3,726, 35%), and shortness of breath (n = 3,533, 33%).
Associations with the rate of falls
Table 2 describes the adjusted associations with the rate of falls among our population-based sample of home care clients in the HNHB health region. All variables had a variance inflation factor less than 1.6, indicating that multicollinearity was not present in the final model. A sensitivity analysis was not conducted because one per cent of observations (n = 153) had a standardized residual greater than two.
Functional characteristics had statistically significant associations with the rate of falls. In particular, declines in activities of daily living were associated with an increased rate of falls (IRR = 1.59, 95% CI 1.49, 1.69; p < 0.001). The use of assistive devices for locomotion indoors also had statistically significant associations with the rate of falls among our sample: scooter (IRR = 2.26, 95% CI 1.42, 3.71; p < 0.001), walker or crutch (IRR = 1.50, 95% CI 1.37, 1.63; p < 0.001), cane (IRR = 1.42, 95% CI 1.28, 1.59; p < 0.001), and wheelchair (IRR = 1.35, 95% CI 1.21, 1.51; p < 0.001) use were all associated with an increased rate of falls. Moderately impaired cognitive skills for daily decision-making were also associated with a 38% increase in the rate of falls (IRR = 1.38, 95% CI 1.24, 1.54; p < 0.001).
Polypharmacy and health conditions had statistically significant associations with the rate of falls. Home care clients who took eight or more drugs had a 21% increase in the rate of falls (IRR = 1.21, 95% CI 1.05, 1.39; p = 0.007), and those who experienced dizziness or lightheadedness had a 43% increase in the rate of falls (IRR = 1.43, 95% CI 1.33, 1.52; p < 0.001). Home care clients who have parkinsonism had a 46% increase in the rate of falls (IRR = 1.46, 95% CI 1.28, 1.67; p < 0.001).
Sex differences
Table 3 describes important differences between males and females observed within functional characteristics. Males who used assistive devices had a higher rate of falls compared to females who used assistive devices for locomotion indoors. For example, males who used a walker or crutch had a 61% increase in the rate of falls (IRR = 1.61, 95% CI 1.60, 1.67; p < 0.001), whereas females had a 43% increase (IRR = 1.43, 95% CI 1.31, 1.45; p = 0.050). Males who used a cane had a 60% increase in the rate of falls (IRR = 1.60, 95% CI 1.60, 1.67; p < 0.001), compared to females who had a 28% increase (IRR = 1.28, 95% CI 1.23, 1.31; p = 0.039).
Differences between males and females were also observed within neurological and cardiovascular health conditions. Specifically, males with these health conditions had a decrease in the rate of falls compared to females with the same conditions. For example, males who had a stroke had an 18% decrease in the rate of falls (IRR = 0.82, 95% CI 0.78, 0.92; p < 0.001), whereas females had a three per cent decrease (IRR = 0.97, 95% CI 0.92, 1.00; p = 0.032). Males with congestive heart failure had a 25% decrease in the rate of falls (IRR = 0.75, 95% CI 0.70, 0.83; p < 0.001), whereas females had a four per cent decrease (IRR = 0.94, 95% CI 0.89, 1.00; p = 0.012).
Subgroup analyses
Tables 4-6 (available as online appendices) describe the subgroup analyses of high-risk groups (i.e., parkinsonism, dizziness and/or lightheadedness, and congestive heart failure). Among home care clients with parkinsonism, the use of a cane was associated with a 129% increase in the rate of falls, compared to home care clients with parkinsonism who did not use an assistive device (IRR = 2.29, 95% CI 1.37, 3.86; p = 0.001). This is a 90% increase in the rate of falls, compared to home care clients who do not have a parkinsonism diagnosis and use a cane for locomotion indoors (IRR = 1.39, 95% CI 1.24, 1.56; p < 0.001). There were also differences between home care clients with parkinsonism and the number of drugs they took and rates of falls. Home care clients with parkinsonism who took eight or more drugs had a 177% increase in the rate of falls (IRR = 2.77, 95% CI 1.13, 6.96; p = 0.027), compared to those who do not have parkinsonism (IRR = 1.18, 95% CI 1.03, 1.36; p = 0.021). In the subgroup analyses of home care clients who experienced dizziness and/or lightheadedness and have congestive heart failure, the findings of these analyses were similar to those who did not experience dizziness and/or lightheadedness and congestive heart failure.