Table 3.
Age- And Gender-Adjusted Rate Ratios, with 95% Confidence Intervals, For Associations Between Baseline Characteristics And All Falls, Indoor Falls, And Outdoor Falls *
| Characteristics | All Falls | Indoor Falls | Outdoor Falls | |||
|---|---|---|---|---|---|---|
| Rate Ratio | 95% CI | Rate Ratio | 95% CI | Rate Ratio | 95% CI | |
| Demographic | ||||||
| white race / ethnicity | 1.53 | (1.19,1.98) | 1.23 | (0.90,1.68) | 2.08 | (1.46,2.96) |
| education level | ||||||
| high school graduate or less | Referent | Referent | Referent | |||
| some college or college graduate | 1.22 | (0.96,1.56) | 1.19 | (0.88,1.61) | 1.33 | (0.97,1.84) |
| graduate studies | 1.76 | (1.37,2.25) | 1.53 | (1.12,2.09) | 2.08 | (1.51,2.87) |
| Lifestyle | ||||||
| body mass index (kg/m2) | ||||||
| <25.0 | Referent | Referent | Referent | |||
| 25.0–29.9 | 0.99 | (0.78,1.25) | 1.12 | (0.83,1.50) | 0.87 | (0.65,1.16) |
| 30.0+ | 0.79 | (0.60,1.03) | 1.14 | (0.82,1.59) | 0.47 | (0.32,0.67) |
| physical activity (bottom quartile, PASE<55) | 1.03 | (0.81,1.31) | 1.43 | (1.07,1.90) | 0.67 | (0.48,0.92) |
| 3 or more flights stairs in home use of alcohol | 1.58 | (1.17,2.13) | 1.17 | (0.80,1.72) | 1.98 | (1.38,2.83) |
| not at all | Referent | Referent | Referent | |||
| 1–3 drinks/month | 1.05 | (0.80,1.38) | 1.05 | (0.75,1.46) | 1.04 | (0.72,1.51) |
| 1–6 drinks/week | 1.16 | (0.89,1.50) | 0.89 | (0.64,1.23) | 1.53 | (1.10,2.12) |
| every day use | 1.39 | (1.01,1.91) | 1.08 | (0.73,1.61) | 1.80 | (1.21,2.67) |
| Physical Disability | ||||||
| balance (Berg score) | ||||||
| 51+ | Referent | Referent | Referent | |||
| 48 -50 | 1.33 | (1.04,1.69) | 1.56 | (1.16,2.11) | 1.18 | (0.87,1.60) |
| <48 | 1.44 | (1.10,1.89) | 2.33 | (1.70,3.19) | 0.66 | (0.45,0.98) |
| unable to do chair-stand test unless using arms | 1.34 | (0.92,1.95) | 1.85 | (1.20,2.86) | 0.68 | (0.38,1.21) |
| gait speed | ||||||
| >1.33 m/sec | Referent | Referent | Referent | |||
| 0.68–1.33m/sec | 0.59 | (0.41,0.87) | 0.95 | (0.57,1.57) | 0.43 | (0.28,0.67) |
| <0.68 m/sec | 0.69 | (0.43,1.10) | 1.48 | (0.81,2.68) | 0.27 | (0.15,0.50) |
| activities of daily living | ||||||
| no difficulty | Referent | Referent | Referent | |||
| little / some difficulty | 1.59 | (1.21,2.10) | 1.98 | (1.43,2.74) | 1.18 | (0.82,1.69) |
| much difficulty / inability | 1.42 | (0.97,2.06) | 2.57 | (1.69,3.90) | 0.27 | (0.13,0.56) |
| short physical performance battery <10 | 1.15 | (0.93,1.42) | 1.69 | (1.30,2.18) | 0.68 | (0.51,0.90) |
| reduced activity due to illness | 1.57 | (1.27,1.95) | 1.75 | (1.34,2.28) | 1.37 | (1.03,1.82) |
| poor vision (worse than 40/100) | 0.80 | (0.55,1.16) | 0.79 | (0.50,1.27) | 0.86 | (0.53,1.40) |
| Illness-Related | ||||||
| moderate-severe bodily pain | 1.02 | (0.83,1.26) | 1.37 | (1.07,1.77) | 0.72 | (0.54,0.94) |
| number of comorbid conditions (per condition) | 1.05 | (0.99,1.13) | 1.17 | (1.08,1.27) | 0.93 | (0.85,1.02) |
| fair/poor self-rated health | 1.29 | (0.97,1.71) | 1.77 | (1.28,2.46) | 0.77 | (0.52,1.15) |
| peripheral neuropathy | 1.32 | (0.97,1.80) | 1.51 | (1.04,2.19) | 1.17 | (0.78,1.76) |
| foot pain | 1.34 | (1.06,1.69) | 1.56 | (1.17,2.06) | 1.08 | (0.79,1.46) |
| knee osteoarthritis | 1.30 | (1.03,1.62) | 1.28 | (0.97,1.70) | 1.31 | (0.98,1.76) |
| depression | 1.96 | (1.37,2.80) | 1.81 | (1.17,2.82) | 2.07 | (1.32,3.26) |
| Medication Use | ||||||
| number of medications | ||||||
| 0–4 | Referent | Referent | Referent | |||
| 5–8 | 0.77 | (0.61,0.96) | 0.90 | (0.68,1.20) | 0.66 | (0.50,0.88) |
| 9+ | 1.14 | (0.86,1.49) | 1.86 | (1.34,2.57) | 0.60 | (0.41,0.87) |
| uses psychotropic medication | 1.36 | (1.07,1.74) | 1.53 | (1.14,2.06) | 1.19 | (0.86,1.64) |
| Cognition | ||||||
| impaired cognition (MMSE 18–24) | 1.02 | (0.74,1.39) | 1.24 | (0.85,1.81) | 0.77 | (0.50,1.18) |
| Fall-Related | ||||||
| number falls in past year (per fall) | 1.30 | (1.21,1.39) | 1.31 | (1.21,1.42) | 1.23 | (1.13,1.34) |
| falls efficacy scale <90 | 1.33 | (0.99,1.77) | 1.73 | (1.23,2.43) | 0.83 | (0.55,1.25) |
*
Rate ratios were estimated using negative binomial regression models. The rate ratio is the average number of falls per person per year of follow-up in one group (e.g., white race/ethnicity) divided by the average number of falls per person per year of follow-up in a referent group (e.g., non-white race/ethnicity). The referent group is specific for each potential risk factor.
Abbreviations: CI = confidence interval; PASE = Physical Activity Scale for the Elderly; MMSE = Mini-Mental State Exam