Table 3.
Univariable and multivariable prevalence ratios (PRs) for the relationship between study variables (sociodemographic characteristics, health factors, and health service use) and employment among adults (ages 18–64 years) in the US with doctor-diagnosed arthritis, National Health Interview Survey (NHIS), 2013–2017*
| Univariable |
Multivariable |
|||
|---|---|---|---|---|
| PR | 95% CI | PR | 95% CI | |
| Depressive symptoms† | ||||
| Yes | 0.46 | 0.42–0.51 | 0.88 | 0.83–0.93 |
| No | 1.00 | – | 1.00 | – |
|
| ||||
| Sociodemographic factors | ||||
| Sex | ||||
| Men | 1.00 | – | 1.00 | – |
| Women | 0.85 | 0.82–0.88 | 0.92 | 0.89–0.95 |
| Age, years | ||||
| Young adult (18–34) | 1.0 | – | 1.00 | – |
| Middle-age adult (35–54) | 0.98 | 0.92–1.05 | 1.04 | 0.99–1.09 |
| Older adult (55–64) | 0.79 | 0.74–0.84 | 0.84 | 0.77–0.89 |
| Race/ethnicity | ||||
| Non-Hispanic White | 1.00 | – | ‡ | – |
| Non-Hispanic Black | 0.84 | 0.79–0.90 | – | – |
| Hispanic | 0.91 | 0.85–0.99 | – | – |
| Non-Hispanic other | 0.93 | 0.84–1.04 | – | – |
| Education | ||||
| Less than high school | 0.71 | 0.65–0.79 | ‡ | – |
| High school or equivalent | 1.00 | – | – | – |
| Some college/associate degree | 1.14 | 1.08–1.21 | – | – |
| College graduate or above | 1.46 | 1.39–1.53 | – | – |
| Income-to-poverty ratio§ | 1.00 | |||
| Poor (<125%) | 1.50 | 1.33–1.70 | 1.21 | 1.10–1.32 |
| Low income (125–199%) | 2.10 | 1.92–2.30 | 1.44 | 1.34–1.55 |
| Middle income (200–400%) | 2.63 | 2.42–2.87 | 1.65 | 1.53–1.77 |
| High income (>400%) | 1.00 | – | – | – |
| Social participation | ||||
| Yes | 0.22 | 0.18–0.26 | 0.78 | 0.70–0.88 |
| No | 1.00 | – | 1.00 | – |
|
| ||||
| Health factors | ||||
| Self-rated health | ||||
| Excellent/very good | 1.00 | – | 1.00 | – |
| Good | 0.85 | 0.81–0.88 | 1.00 | 0.96–1.05 |
| Fair/poor | 0.38 | 0.36–0.41 | 0.83 | 0.78–0.88 |
| Self-reported anxiety symptoms | ||||
| Yes | 0.64 | 0.60–0.69 | ‡ | – |
| No | 1.00 | – | – | – |
| Body mass index, kg/m2 | ‡ | |||
| Under/healthy weight (<25.0) | 1.00 | – | – | – |
| Overweight (25.0–29.9) | 1.06 | 1.01–1.12 | – | – |
| Obese (≥30.0) | 0.94 | 0.89–1.00 | – | – |
| Number of comorbid conditions¶ | ||||
| 0 | 1.00 | – | 1.00 | – |
| 1–2 | 0.80 | 0.77–0.83 | 0.95 | 0.91–0.99 |
| ≥3 | 0.44 | 0.40–0.49 | 0.90 | 0.85–0.96 |
| Arthritis-attributable activity limitations | ||||
| Yes | 0.53 | 0.51–0.56 | 0.84 | 0.81–0.88 |
| No | 1.00 | – | 1.00 | – |
| Aerobic physical activity level# | ||||
| Inactive | 1.00 | – | – | – |
| Insufficiently active | 1.37 | 1.29 –1.46 | – | – |
| Active | 1.56 | 1.48 –1.64 | – | – |
| Functional limitations** | ||||
| 0 | 1.00 | – | 1.00 | – |
| 1–3 | 0.59 | 0.55–0.62 | 0.85 | 0.81–0.90 |
| ≥4 | 0.22 | 0.19–0.26 | 0.70 | 0.61–0.78 |
|
| ||||
| Health service use | ||||
| Ambulatory care visits in past year | ||||
| 0–3 | 1.00 | – | 1.00 | – |
| 4–9 | 0.82 | 0.79–0.86 | 0.94 | 0.90–0.98 |
| 10–15 | 0.66 | 0.62–0.71 | 0.91 | 0.87–0.96 |
| ≥16 | 0.58 | 0.54–0.64 | 0.93 | 0.93–0.99 |
| Usual place for care | ||||
| Yes | 0.98 | 0.91 - 1.06 | – | – |
| No | 1.00 | – | ‡ | – |
| Health insurance | ||||
| Not covered | 1.00 | – | ‡ | – |
| Covered | 1.17 | 1.09–1.26 | – | – |
|
| ||||
| Interaction effects of depressive symptoms (age, years)†† | ||||
| Young adult (18–34) | – | – | 0.86 | 0.74–0.99 |
| Middle-age adult (35–54) | – | – | 0.83 | 0.77–0.90 |
| Older adults (55–64) | – | – | 0.94 | 0.86–1.03 |
Doctor-diagnosed arthritis was identified by“yes” to the question “Have you ever been told by a doctor or other health professional that you have some form of arthritis, rheumatoid arthritis, gout, lupus, or fibromyalgia?” 95% CI = 95% confidence interval.
For depressive symptoms, participants were asked about the frequency (“How often do you feel depressed?” [daily, weekly, monthly, a few times a year, never, or refused/don’t know]) and intensity (“Thinking about the last time you felt depressed, how depressed did you feel?” [a lot, in between a little and a lot, a little, or refused/don’t know]) of depressive symptoms. Participants were categorized as reporting depressive symptoms by reporting “daily” or “weekly” for symptom frequency and “a lot” or “in between a little and a lot” for depressive symptom intensity.
Variable not included in the multivariable model as a result of our backwards elimination strategy.
Calculated using imputed income files from the NHIS and based on total family income and family size.
Nine possible comorbid conditions examined were hypertension, heart diseases, stroke, diabetes mellitus, asthma, cancer, weak or failing kidneys, hepatitis, and chronic obstructive pulmonary disease.
Physically active (≥150 minutes moderate-intensity, leisure time, aerobic physical activity/week), insufficiently active (1–149 minutes moderate-intensity, leisure time, aerobic physical activity/week) or inactive (0 minutes moderate-intensity, leisure time, aerobic physical activity/week).
Number of functional limitations was measured for 9 tasks (e.g., push/pull large objects, walk one-fourth mile, stand for 2 hours, sit for 2 hours, stoop/bend/kneel, reach over one’s head, grasp small objects, climb stairs, lift or carry 10 pounds); limitation was identified for responses of “very difficult” or “can’t do.”
Reference is no depressive symptoms.