Table 3. Prevalence ratios and 95% confidence intervals from the multivariate Poisson regression for polypharmacy defined as five or more medicines concomitantly.
| Variables | Prevalence ratio | 95%CI |
| Age (ref: 50-59) | ||
| 60-69 | 1.441*** | 1.279 - 1.622 |
| 70-79 | 1.641*** | 1.375 - 1.959 |
| 80+ | 2.049*** | 1.660 - 2.530 |
| Gender (ref: Female) | 1.008 | 0.883 - 1.150 |
| Race (ref: White) | ||
| Black | 0.744* | 0.574 - 0.962 |
| Brown | 0.974 | 0.845 - 1.122 |
| Others | 1.010 | 0.718 - 1.422 |
| Region (ref: North) | ||
| Northeast | 1.378 | 0.925 - 2.053 |
| Southeast | 2.181*** | 1.500 - 3.173 |
| South | 2.492*** | 1.628 - 3.815 |
| Central-West | 1.591* | 1.067 - 2.373 |
| Education (ref: < 5 years of schooling) | ||
| Between 5 and 8 years | 1.185* | 1.025 - 1.370 |
| 9 or more years | 1.073 | 0.934 - 1.233 |
| Household income (ref: < 2 Minimum Wages) | ||
| 2-5 Minimum Wages | 0.994 | 0.853 - 1.158 |
| 5-9 Minimum Wages | 1.067 | 0.858 - 1.327 |
| 9+ Minimum Wages | 1.094 | 0.880 - 1.361 |
| Living with partner (ref: No) | 0.916 | 0.794 - 1.056 |
| Chronic conditions (ref: None) | ||
| One | 3.388*** | 2.259 - 5.082 |
| Two | 7.549*** | 5.200 - 10.96 |
| Three or more | 12.44*** | 8.701 - 17.80 |
| Poor self-rated health (ref: No) | 1.201** | 1.057 - 1.364 |
| Drink (ref: no) | ||
| Eventually | 0.802 | 0.621 - 1.036 |
| Regularly | 0.715** | 0.586 - 0.872 |
| Body Mass Index (ref: Normal) | ||
| Overweight | 1.135 | 0.959 - 1.344 |
| Obese | 1.373*** | 1.170 - 1.611 |
| Private Health Plan (ref: no) | 0.861 | 0.720 - 1.030 |
| Medical office visits (ref: none) | ||
| 1-2 visits | 2.389** | 1.405 - 4.062 |
| 3-4 visits | 2.920*** | 1.844 - 4.623 |
| 5+ visits | 3.584*** | 2.252 - 5.703 |
| Specialist visits | ||
| 1 visit | 1.103 | 0.854 - 1.424 |
| 2 visits | 1.419* | 1.084 - 1.859 |
| 3+ visits | 1.578*** | 1.278 - 1.949 |
| Usual source of care (ref: no) | 1.134 | 0.987 - 1.304 |
| Seen by the same physician (ref: never or rarely) | ||
| Always or most of the time | 1.259** | 1.097 - 1.445 |
| Physicians know all medication (ref: never or rarely) | ||
| Always or most of the time | 1.440* | 1.076 - 1.928 |
| Need to see GP to book specialty care (ref: no) | 0.799** | 0.695 - 0.919 |
| Admitted to a hospital in the past 12 months (ref: no) | 1.151 | 0.978 - 1.355 |
| Any difficulty managing all medication (ref: no) | 1.191* | 1.030 - 1.376 |
| Any barrier to drug access (ref: no) | 1.077 | 0.958 - 1.210 |
| Observations | 7,877 |
Adjusted prevalence rations from survey-adjusted Poisson regression.
*
p<0.05
**
p<0.01,
***
p<0.001,