TABLE 3—
Weighted Multivariate Logistic Regressions of Cost-Related Medication Underuse on Food Security and Relevant Controls Among US Adults Aged 18–64 Years (n = 44 574): National Health Interview Survey, 2011 and 2012
| Predictors | Skipped Medication, OR (95% CI) | Took Less Medication, OR (95% CI) | Delayed Filling Prescription, OR (95% CI) | Lower-Cost Medication, OR (95% CI) | Could Not Afford Medication, OR (95% CI) | At Least 1 of the 5, OR (95% CI) |
| Food security | ||||||
| High (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Marginal | 1.66*** (1.45, 1.91) | 1.58*** (1.40, 1.79) | 1.77*** (1.58, 1.99) | 1.54*** (1.39, 1.70) | 1.91*** (1.68, 2.17) | 1.67*** (1.52, 1.82) |
| Low | 2.51*** (2.21, 2.85) | 2.54*** (2.25, 2.86) | 2.62*** (2.32, 2.96) | 1.74*** (1.58, 1.92) | 2.94*** (2.63, 3.28) | 2.22*** (2.04, 2.42) |
| Very low | 3.71*** (3.25, 4.23) | 3.80*** (3.36, 4.30) | 4.03*** (3.58, 4.54) | 2.15*** (1.93, 2.39) | 4.27*** (3.76, 4.85) | 3.07*** (2.78, 3.40) |
| Gender | ||||||
| Female (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Male | 0.62*** (0.56, 0.68) | 0.61*** (0.56, 0.68) | 0.55*** (0.51, 0.60) | 0.59*** (0.56, 0.63) | 0.62*** (0.57, 0.68) | 0.57*** (0.54, 0.60) |
| Age | 1.01** (1.00, 1.01) | 1.01** (1.00, 1.01) | 1.00 (1.00, 1.00) | 1.00 (1.00, 1.00) | 1.00* (0.99, 1.00) | 1.00 (1.00, 1.00) |
| Marital status | ||||||
| Married (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Never married | 0.87* (0.76, 1.00) | 0.9 (0.79, 1.03) | 0.82** (0.73, 0.93) | 0.72*** (0.66, 0.79) | 0.91 (0.80, 1.05) | 0.75*** (0.69, 0.82) |
| Separated or divorced | 1.15* (1.00, 1.32) | 1.15* (1.00, 1.31) | 1.07 (0.94, 1.21) | 0.95 (0.86, 1.04) | 1.25** (1.09, 1.43) | 0.97 (0.89, 1.07) |
| Widowed | 0.9 (0.70, 1.15) | 1.01 (0.79, 1.28) | 0.91 (0.72, 1.15) | 0.86 (0.71, 1.03) | 1.15 (0.92, 1.44) | 0.87 (0.73, 1.03) |
| Family type | ||||||
| 1 adult, no children (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Multiple adults, no children | 1.01 (0.88, 1.16) | 0.99 (0.87, 1.13) | 0.92 (0.81, 1.05) | 1.03 (0.94, 1.13) | 1.16* (1.02, 1.33) | 1.04 (0.96, 1.14) |
| 1 adult, ≥ 1 children | 1.24* (1.05, 1.47) | 1.21* (1.03, 1.43) | 1.23** (1.05, 1.44) | 1.07 (0.95, 1.21) | 1.06 (0.91, 1.23) | 1.07 (0.96, 1.19) |
| Multiple adults, ≥ 1 children | 1.11 (0.95, 1.30) | 1.12 (0.97, 1.30) | 1.12 (0.97, 1.28) | 0.99 (0.90, 1.10) | 1.13 (0.97, 1.31) | 1.01 (0.92, 1.11) |
| Race/ethnicity | ||||||
| Non-Hispanic White (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Hispanic | 0.98 (0.86, 1.12) | 0.95 (0.83, 1.08) | 0.96 (0.86, 1.07) | 0.85*** (0.78, 0.93) | 1.09 (0.96, 1.22) | 0.89** (0.83, 0.96) |
| Non-Hispanic Black | 0.79*** (0.70, 0.88) | 0.85** (0.76, 0.96) | 0.87* (0.79, 0.97) | 0.73*** (0.67, 0.80) | 0.97 (0.87, 1.08) | 0.78*** (0.72, 0.84) |
| Non-Hispanic Asian | 1.03 (0.80, 1.31) | 0.92 (0.74, 1.15) | 0.84 (0.68, 1.04) | 0.88 (0.76, 1.01) | 0.77* (0.63, 0.94) | 0.81** (0.71, 0.92) |
| Non-Hispanic other | 1.02 (0.65, 1.62) | 0.97 (0.61, 1.53) | 0.94 (0.60, 1.49) | 0.85 (0.59, 1.21) | 0.96 (0.59, 1.55) | 0.81 (0.60, 1.10) |
| US citizenship | ||||||
| US citizen (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Non-US citizen | 0.89 (0.76, 1.05) | 0.9 (0.77, 1.06) | 0.75*** (0.65, 0.88) | 0.72*** (0.64, 0.81) | 0.85* (0.74, 0.99) | 0.77*** (0.69, 0.85) |
| Income-to-poverty ratio | ||||||
| < 1.00 | 1.49*** (1.24, 1.80) | 1.39*** (1.17, 1.66) | 1.28** (1.09, 1.50) | 1.02 (0.91, 1.15) | 2.03*** (1.70, 2.43) | 1.13* (1.01, 1.27) |
| 1.00–1.99 | 1.83*** (1.56, 2.14) | 1.59*** (1.36, 1.86) | 1.61*** (1.39, 1.87) | 1.28*** (1.15, 1.42) | 2.12*** (1.80, 2.48) | 1.34*** (1.21, 1.48) |
| 2.00–2.99 | 1.88*** (1.60, 2.21) | 1.70*** (1.45, 1.99) | 1.74*** (1.51, 2.00) | 1.35*** (1.22, 1.49) | 1.90*** (1.63, 2.21) | 1.40*** (1.27, 1.54) |
| 3.00–3.99 | 1.55*** (1.31, 1.83) | 1.50*** (1.26, 1.77) | 1.70*** (1.45, 1.98) | 1.31*** (1.18, 1.46) | 1.69*** (1.41, 2.03) | 1.33*** (1.19, 1.47) |
| ≥ 4.00 (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Highest family education | ||||||
| < high school (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| High-school graduate/GED | 1.29** (1.10, 1.52) | 1.30** (1.11, 1.52) | 1.30*** (1.12, 1.50) | 1.27*** (1.12, 1.44) | 1.21** (1.06, 1.38) | 1.19** (1.06, 1.34) |
| Some college/associate’s degree | 1.47*** (1.25, 1.72) | 1.49*** (1.28, 1.73) | 1.62*** (1.40, 1.88) | 1.46*** (1.30, 1.64) | 1.52*** (1.32, 1.74) | 1.40*** (1.26, 1.56) |
| < college grad | 1.57*** (1.31, 1.89) | 1.52*** (1.27, 1.80) | 1.69*** (1.45, 1.98) | 1.66*** (1.46, 1.89) | 1.59*** (1.36, 1.86) | 1.62*** (1.44, 1.82) |
| Proportion adult family membersa | ||||||
| Working part time | 0.89 (0.77, 1.03) | 0.87 (0.75, 1.00) | 0.89 (0.79, 1.01) | 0.95 (0.86, 1.04) | 0.96 (0.83, 1.11) | 0.94 (0.85, 1.03) |
| Not in the labor force | 0.55*** (0.48, 0.64) | 0.53*** (0.47, 0.61) | 0.54*** (0.48, 0.62) | 0.65*** (0.59, 0.73) | 0.67*** (0.58, 0.77) | 0.60*** (0.55, 0.66) |
| Home tenure status | ||||||
| Owned/other (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Rented | 1.05 (0.96, 1.15) | 1.03 (0.93, 1.13) | 1.17*** (1.07, 1.28) | 0.96 (0.89, 1.02) | 1.14** (1.04, 1.25) | 1.01 (0.95, 1.07) |
| Health insurance coverage | ||||||
| No coverage | 3.04*** (2.76, 3.35) | 3.05*** (2.76, 3.36) | 2.97*** (2.71, 3.24) | 1.63*** (1.52, 1.75) | 4.62*** (4.22, 5.07) | 2.44*** (2.28, 2.61) |
| Partial coverage | 2.46*** (2.09, 2.89) | 2.67*** (2.27, 3.15) | 2.88*** (2.47, 3.35) | 1.72*** (1.53, 1.95) | 3.68*** (3.19, 4.24) | 2.20*** (1.95, 2.48) |
| Full coverage (Ref) | 1.00 | 1.00 | 1.00 | |||
| Diagnosed with chronic condition | 2.07*** (1.85, 2.31) | 1.99*** (1.79, 2.21) | 2.09*** (1.91, 2.28) | 1.77*** (1.66, 1.89) | 1.92*** (1.76, 2.10) | 1.90*** (1.79, 2.02) |
| Has a functional limitation | 1.78*** (1.60, 1.99) | 1.90*** (1.72, 2.10) | 1.88*** (1.72, 2.07) | 1.57*** (1.46, 1.69) | 1.79*** (1.64, 1.96) | 1.70*** (1.59, 1.82) |
| Severe mental illness | 1.88*** (1.63, 2.17) | 2.00*** (1.74, 2.29) | 1.87*** (1.63, 2.14) | 1.57*** (1.37, 1.79) | 1.87*** (1.63, 2.14) | 1.90*** (1.68, 2.16) |
| Proportion adult family members | ||||||
| Needing help with ADL | 0.98 (0.72, 1.33) | 0.9 (0.65, 1.24) | 0.67** (0.50, 0.90) | 0.90 (0.68, 1.19) | 0.87 (0.64, 1.17) | 0.82 (0.62, 1.08) |
| With health-related work limitation | 0.99 (0.83, 1.19) | 0.97 (0.82, 1.15) | 1.08 (0.92, 1.28) | 1.09 (0.94, 1.26) | 1.20 (1.00, 1.46) | 1.12 (0.97, 1.30) |
| Limited in any way | 1.15*** (1.06, 1.24) | 1.16*** (1.08, 1.25) | 1.17*** (1.09, 1.26) | 1.11*** (1.05, 1.18) | 1.14** (1.05, 1.23) | 1.12*** (1.05, 1.18) |
| With self-rated health statusb | ||||||
| Excellent | 0.64*** (0.55, 0.74) | 0.59*** (0.52, 0.68) | 0.64*** (0.56, 0.74) | 0.78*** (0.71, 0.86) | 0.62*** (0.54, 0.71) | 0.74*** (0.67, 0.81) |
| Very good | 0.71*** (0.62, 0.81) | 0.69*** (0.60, 0.78) | 0.77*** (0.68, 0.87) | 0.88** (0.80, 0.96) | 0.68*** (0.59, 0.78) | 0.87** (0.80, 0.95) |
| Fair | 1.25** (1.08, 1.45) | 1.17* (1.01, 1.34) | 1.24** (1.06, 1.44) | 1.21** (1.06, 1.37) | 1.23** (1.06, 1.44) | 1.29*** (1.15, 1.46) |
| Poor | 1.61*** (1.27, 2.05) | 1.51*** (1.19, 1.92) | 1.53*** (1.20, 1.96) | 1.15 (0.94, 1.43) | 1.39** (1.10, 1.75) | 1.24* (1.02, 1.50) |
| BMI category (kg/m2) | ||||||
| Underweight (< 18.5) | 0.9 (0.65, 1.24) | 0.96 (0.69, 1.33) | 0.70* (0.52, 0.94) | 0.95 (0.74, 1.21) | 0.73 (0.52, 1.02) | 0.91 (0.73, 1.14) |
| Normal weight (18.5–24.99; Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Overweight (25–29.99) | 1.05 (0.94, 1.18) | 1.08 (0.97, 1.21) | 1.02 (0.92, 1.14) | 1.09* (1.00, 1.18) | 1.12* (1.01, 1.25) | 1.06 (0.99, 1.15) |
| Obese (30–39.99) | 1.06 (0.96, 1.18) | 1.06 (0.95, 1.17) | 1.08 (0.98, 1.20) | 1.14** (1.05, 1.23) | 1.13* (1.02, 1.25) | 1.09* (1.01, 1.17) |
| Severely obese (≥ 40) | 1.27** (1.07, 1.51) | 1.17 (0.97, 1.40) | 1.19* (1.01, 1.40) | 1.21** (1.07, 1.37) | 1.30** (1.10, 1.53) | 1.16* (1.04, 1.31) |
| Smoking status | ||||||
| Never smoked (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Current smoker | 1.15* (1.03, 1.28) | 1.09 (0.98, 1.20) | 1.12* (1.02, 1.24) | 1.02 (0.94, 1.10) | 1.31*** (1.18, 1.45) | 1.09* (1.01, 1.17) |
| Former smoker | 1.08 (0.96, 1.20) | 1.08 (0.96, 1.21) | 1.15* (1.03, 1.28) | 1.13** (1.04, 1.22) | 1.23*** (1.10, 1.37) | 1.14*** (1.06, 1.23) |
| Alcohol use | ||||||
| Lifetime abstainer (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Former drinker | 1.06 (0.91, 1.25) | 1.13 (0.97, 1.31) | 1.12 (0.98, 1.29) | 1.29*** (1.16, 1.44) | 1.17* (1.01, 1.35) | 1.29*** (1.16, 1.44) |
| Current light or moderate | 1.08 (0.96, 1.22) | 1.13 (1.00, 1.27) | 1.16** (1.04, 1.30) | 1.30*** (1.18, 1.42) | 1.27*** (1.13, 1.43) | 1.34*** (1.23, 1.46) |
| Current heavy | 1.02 (0.82, 1.26) | 1.00 (0.81, 1.25) | 1.09 (0.91, 1.31) | 1.18* (1.01, 1.37) | 1.20 (0.98, 1.47) | 1.26** (1.09, 1.45) |
| US region of residence | ||||||
| South (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Northeast | 0.91 (0.80, 1.04) | 0.83* (0.71, 0.96) | 0.75*** (0.66, 0.86) | 0.59*** (0.54, 0.65) | 0.86* (0.76, 0.98) | 0.65*** (0.60, 0.72) |
| Midwest | 0.94 (0.84, 1.05) | 0.85** (0.76, 0.96) | 0.85** (0.77, 0.94) | 0.87*** (0.80, 0.94) | 0.90* (0.81, 1.00) | 0.92* (0.85, 0.99) |
| West | 0.93 (0.83, 1.05) | 0.98 (0.87, 1.09) | 0.85** (0.76, 0.94) | 0.71*** (0.64, 0.79) | 0.92 (0.84, 1.01) | 0.81*** (0.75, 0.88) |
| Year of survey | ||||||
| 2011 (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| 2012 | 0.88** (0.81, 0.95) | 0.90* (0.83, 0.98) | 0.87*** (0.81, 0.94) | 0.95 (0.89, 1.01) | 0.89** (0.82, 0.96) | 0.93* (0.88, 0.99) |
| Constant | 0.011*** (0.008, 0.017) | 0.013*** (0.009, 0.019) | 0.021*** (0.015, 0.030) | .016*** (0.083, 0.137) | 0.012*** (0.008, 0.017) | 0.116*** (0.091, 0.148) |
Note. ADL = activities of daily living; BMI = body mass index; CI = confidence interval; GED = general equivalence diploma; OR = odds ratio.
a
The proportion of family members working full time was omitted because of collinearity; however, when proportion working part time was omitted and the proportion working full time was included, it was not significant in the final model for any of the outcomes. This also applies to proportion looking for work.
b
The proportion of family members with good health status was omitted from the regression because of collinearity. When the self-rated health status variables were replaced with a binary variable on whether any family member had a self-rated health status of fair or bad, the results were similar to that using the proportions.
*P < .05; **P < .01; ***P < .001.