Anxiety and Depression Among US Adults With Arthritis: Prevalence and Correlates
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Arthritis Care & Research
Vol. 64, No. 7, July 2012, pp 968 –976
DOI 10.1002/acr.21685
© 2012, American College of Rheumatology
ORIGINAL ARTICLE
Anxiety and Depression Among US Adults With
Arthritis: Prevalence and Correlates
LOUISE B. MURPHY,1 JEFFREY J. SACKS,2 TERESA J. BRADY,1 JENNIFER M. HOOTMAN,1 AND
DANIEL P. CHAPMAN1
Objective. There has been limited characterization of the burden of anxiety and depression, especially the former,
among US adults with arthritis in the general population. The study objective was to estimate the prevalence and
correlates of anxiety and depression among US adults with doctor-diagnosed arthritis.
Methods. The study sample comprised US adults ages >45 years with doctor-diagnosed arthritis (n ⴝ 1,793) from the
Arthritis Conditions Health Effects Survey (a cross-sectional, population-based, random-digit– dialed telephone interview
survey). Anxiety and depression were measured using separate and validated subscales of the Arthritis Impact Mea-
surement Scales. Prevalence was estimated for the sample overall and stratified by subgroups. Associations between
correlates and each condition were estimated with prevalence ratios and 95% confidence intervals using logistic
regression models.
Results. Anxiety was more common than depression (31% and 18%, respectively); overall, one-third of respondents
reported at least 1 of the 2 conditions. Most (84%) of those with depression also had anxiety. Multivariable logistic
regression modeling failed to identify a distinct profile of characteristics of those with anxiety and/or depression. Only
half of the respondents with anxiety and/or depression had sought help for their mental health condition in the past year.
Conclusion. Despite the clinical focus on depression among people with arthritis, anxiety was almost twice as common
as depression. Given their high prevalence, their profound impact on quality of life, and the range of effective treatments
available, we encourage health care providers to screen all people with arthritis for both anxiety and depression.
INTRODUCTION Anxiety and depression are generally more common
among people with arthritis than in the general population
Depression, a well-documented comorbidity among peo-
(8,9), and interplay independently and synergistically
ple with chronic diseases, including arthritis (1– 6), can
with clinical outcomes such as pain and disability (10,11).
exacerbate functional disabilities (1), affect adherence to
Many studies examining the occurrence of these condi-
treatment (2), and be a barrier to self-care and self-man-
tions among people with arthritis have studied depression
agement behaviors (3,4). Despite its high prevalence in the
general population and equal or stronger incapacitating only, have studied people with one type of arthritis (e.g.,
effects on physical function (5), anxiety is often underrec- rheumatoid arthritis), or were clinic-based, not popula-
ognized and undertreated (6). Until recently, anxiety has tion-based, samples (4,12–17). International population-
been regarded largely as a comorbidity of depression, but based studies identifying major depression using the
its independent effects, including its role as a potential World Health Organization Composite International Diag-
risk factor for depression, are increasingly recognized (7). nostic Interview (WHO-CIDI) indicate prevalences ranging
from 2.2% (Japan) to 19% (Ukraine; in the US, age ⱖ18
years ⫽ 7–9% and age 54 – 65 years ⫽ 11%) (9,18,19). The
The findings and conclusions in this report are those of prevalence of anxiety disorders among people with arthri-
the authors and do not necessarily represent the official
position of the Centers for Disease Control and Prevention.
tis also varies internationally; a survey of 18 countries in
1
Louise B. Murphy, PhD, Teresa J. Brady, PhD, Jennifer M. the early 2000s found that people with arthritis were con-
Hootman, PhD, Daniel P. Chapman, PhD: CDC, Atlanta, sistently more likely than those without arthritis to have
Georgia; 2Jeffrey J. Sacks, MD, MPH: Sue Binder Consulting, anxiety disorders. Additionally, across the countries sur-
Inc., Atlanta, Georgia.
Address correspondence to Louise B. Murphy, PhD, Ar-
veyed, US adults with arthritis had the first or second
thritis Program, Division of Population Health, CDC, 4770 highest prevalence of each of the 4 specific anxiety disor-
Buford Highway NE, Mailstop K-51, Atlanta, GA 30341. ders examined (generalized anxiety disorder [6%], social
E-mail: lmurphy1@cdc.gov. phobia [8%], agoraphobia/panic disorder [3%], and post-
Submitted for publication October 11, 2011; accepted in
revised form March 20, 2012. traumatic stress disorder [5%] [18]). The 2001–2003 US
National Comorbidity Study Replication found that each
968Anxiety and Depression in US Adults With Arthritis 969
representation and reduce sample variation, the numbers
Significance & Innovations were then sorted by census division and metropolitan
● One-third of US adults with arthritis ages ⱖ45 status (i.e., urban versus rural counties) in each stratum.
years reported having at least one of anxiety Numbers were then selected with equal probability within
and/or depression. each of the 7 strata, with oversampling in those strata with
● Although there is considerable clinical and re- high percentages of Hispanics and non-Hispanic blacks
search focus on depression among people with (21).
arthritis, anxiety was more common than depres- To maximize response rates, letters were mailed to the
sion (31% and 18%, respectively). addresses associated with potential residential phone
numbers at least 2 weeks prior to the first call. Trained
● A distinct profile of those with anxiety and/or
interviewers called each number to identify 1) residential
depression did not emerge in the multivariable
numbers and 2) household members who were ages ⱖ45
models, indicating that all people with arthritis
years and had doctor-diagnosed arthritis or chronic joint
should be screened for anxiety and depression.
symptoms. We restricted our analysis to respondents with
● Only half of the respondents with anxiety and/or doctor-diagnosed arthritis (n ⫽ 1,793), who were identi-
depression had sought help for their mental health fied with a response of “yes” to: “Have you ever been told
condition in the past year, suggesting there is an by a doctor or other health professional that you have some
unmet need for treatment of mental health condi- form of arthritis, rheumatoid arthritis, gout, lupus, or fi-
tions among people with arthritis. bromyalgia?” Given this method of case ascertainment, in
this article, arthritis refers to people with arthritis and
other rheumatic conditions. Interviews were conducted in
English (or Spanish as needed) from June 2005 to April
2006. All residents in each household who met the inclu-
of the 6 anxiety disorders measured was more common sion criteria were eligible. Participants were compensated
among people with arthritis (the prevalence among people with a 100-minute prepaid long-distance phone card or a
with arthritis ranged from 1% for agoraphobia to 6% for $5 donation to the Arthritis Foundation. Among eligible
social phobia; 10% reported a specific phobia) (9). All households, Council on American Survey Research Orga-
anxiety disorders were measured using the WHO-CIDI. A nizations response and completion rates were 51% and
study of Australians ages ⱖ18 years with arthritis indi- 86%, respectively (i.e., those with at least 1 age-eligible
cated that one-quarter had experienced an anxiety disor- resident). Response and completion rates for eligible peo-
der in the past 12 months (19). A comparable estimate for ple in the household were 31% and 75% for the first
the US is lacking. household participant identified as eligible and 16% and
To better characterize the burden of anxiety and depres-
80% among other eligible respondents in the same house-
sion among US adults with arthritis, we estimated the
hold, respectively (21). The ACHES protocol was ap-
prevalence of each in a national sample of adults ages ⱖ45
proved by the CDC Institutional Review Board.
years with self-reported doctor-diagnosed arthritis. As de-
Using a standardized questionnaire, interviewers col-
pression and anxiety can be highly responsive to clinical
lected information on sociodemographic characteristics
treatment (20), better recognition and detection of these
and medical and psychosocial aspects of arthritis, includ-
conditions is a necessary first step to reducing the burden
ing physical functioning and limitations, work effects,
of these mental health conditions among people with ar-
knowledge and attitudes about arthritis, self-management
thritis. Therefore, we also examined the correlates of each
and self-care behaviors, and mental health. ACHES meth-
condition to identify the sociodemographic, clinical, and
ods are described in detail elsewhere (21–23).
other characteristics that can help health care providers
(HCPs) identify those who are likely to have anxiety
and/or depression. Study outcomes. Anxiety and depression were assessed
using the Arthritis Impact Measurement Scales (AIMS).
Originally developed for use in longitudinal trials of rheu-
MATERIALS AND METHODS matoid arthritis to detect changes over time (24), AIMS
was subsequently validated for use in studies of other
Study sample. We analyzed data from the Arthritis Con- arthritis types (25).
ditions Health Effects Survey (ACHES), a cross-sectional, The AIMS anxiety and depression module comprises 12
random-digit– dialed telephone survey. ACHES, con- questions (6 for anxiety and 6 for depression) and mea-
ducted by the Centers for Disease Control and Prevention sures the frequency of symptoms (rating of 0 – 6; see Sup-
(CDC), was designed to be representative of the civilian plementary Appendix A, available in the online version of
noninstitutionalized US population of adults ages ⱖ45 this article at http://onlinelibrary.wiley.com/journal/
years with arthritis and/or chronic joint symptoms (21). 10.1002/(ISSN)1529-0131a) in the past month. Following a
Telephone numbers were selected from a proprietary list validation study that reported that an AIMS depression
linking phone numbers to US Census blocks. These num- subscale score of ⱖ4 was comparable to the Center for
bers were first partitioned into 7 strata based on census- Epidemiologic Studies Depression Scale (CES-D) score
estimated percentages of Hispanics and non-Hispanic cutoff for probable depression (16), multiple subsequent
blacks associated with each block. To ensure geographic studies using AIMS to quantify the occurrence of anxiety970 Murphy et al
and depression among people with arthritis have used ⱖ4 the participants rated their confidence on 3 aspects of
as the threshold for both conditions (4,14,16). Consistent self-management: belief that self-management education
with this, for each condition, we calculated the average (SME) courses would help to manage arthritis or joint
subscale value and defined the presence of the condition symptoms, ability to manage arthritis or joint symptoms,
as a mean value of ⱖ4. and ability to engage in moderate physical activity at least
Following the series of AIMS questions, respondents 3 times/week.
reported help-seeking behaviors (“During the past 12
months, have you sought help for stress, depression, or Statistical analysis. We examined the prevalence of
problems with emotions?”) and from whom this help was anxiety and depression (to estimate the public health bur-
sought (i.e., “Did you seek help from any of the following: den) and then stratified by independent variables to iden-
Family or friends? A self-help group or support group? A tify potential correlates for logistic regression models. For
priest, minister, rabbi, or other religious counselor? A ther- each outcome, we estimated the associations with inde-
apist or counselor? A physician?”). pendent variables with unadjusted and multivariable ad-
justed prevalence ratios (PRs) and 95% confidence inter-
Independent variables. We examined variables repre- vals (95% CIs) (30). Last, we determined the proportion of
senting 3 domains of interest: 1) sociodemographic char- respondents with anxiety and/or depression who had
acteristics (i.e., age, sex, race/ethnicity, highest educa- sought help for mental health conditions in the past 12
tional attainment, and current employment status) to months and estimated the likelihood, with PRs and 95%
develop a profile of affected individuals, 2) arthritis symp- CIs, of help seeking for anxiety, depression, and both con-
toms and physical function that can increase the likeli- ditions.
hood of arthritis and depression, and 3) potentially mod- Sampling weights, based on the distribution of US
ifiable health and self-management behaviors that are adults ages ⱖ45 years with arthritis in the 2003–2005
associated with arthritis symptoms and mental and phys- National Health Interview Survey (NHIS) (21), were ap-
ical function. plied in all analyses to infer estimates to the national
Respondents reported the severity of each of 3 symp- population of civilian noninstitutionalized adults ages
toms (i.e., joint pain or aching, stiffness, and fatigue) in the ⱖ45 years with doctor-diagnosed arthritis. Statistical sig-
past 7 days using a 0 –10 scale (where 0 ⫽ no symptoms nificance was defined using 2 criteria: nonoverlapping
95% CIs and a Wald’s test (test of statistical significance of
and 10 ⫽ most severe) and the number of days that they
variable overall in the model) P value of less than or equal
had experienced joint pain or aching in the past 7 days.
to 0.05. Analyses conducted in SAS, version 9.1 and
The survey included the Short Form 36 (SF-36) physical
SUDAAN, version 10 (Research Triangle Institute) ac-
functioning subscales and a series of questions about the
counted for the complex survey design.
degree to which arthritis interfered with routine activities
(e.g., spending time with family and friends, errands/shop-
ping, and household chores) (21,26). The SF-36 and inter-
ference variables were measured using Likert-style re- RESULTS
sponse scales (a lot, a little, or not at all), which we
dichotomized (a lot versus a little/not at all). We analyzed Among adults with arthritis, 30.5% (11.5 million) reported
individual items rather than the SF-36 score, since these anxiety, 17.5% (6.6 million) reported depression, and
individual items correspond to questions clinicians might 14.7% (5.5 million) reported both. Most respondents with
use when asking about patients’ physical function. Initial depression also had anxiety (84%), whereas half of those
analysis showed moderate to strong correlations among with anxiety also had depression (49.5%) (Figure 1).
the function (r ⫽ 0.4 – 0.8) and interference variables (r ⫽
0.5– 0.8). Therefore, we restricted analyses to 3 function
variables (difficulty in walking several hundred feet, wash-
ing or bathing, and bending, kneeling, or stooping) and 1
interference variable (difficulty with errands and shop-
ping). These physical function and interference variables
have been associated with loss of independence among
Depression Only
people with arthritis (27) and loss of independence has Anxiety Only Anxiety & Depression 1.0 million
been correlated with depression in at least one previous
6.0 million 5.5 million
study (4).
Physical activity was measured with 6 validated ques-
tions on frequency and duration of participation in leisure-
time activities of moderate or vigorous intensity (28). Cat-
egories were based on the total number of minutes of
physical activity each week, where 1 minute of vigorous
exercise was equivalent to 2 minutes of moderate activity:
recommended (ⱖ150 minutes), insufficient (10 –149 min- Figure 1. Number of US adults ages ⱖ45 years with arthritis who
utes), or inactive (⬍10 minutes) (29). Using a 0 –10 scale have anxiety and/or depression, 2005–2006, Arthritis Conditions
(where 0 ⫽ no confidence and 10 ⫽ highest confidence), Health Effects Survey.Anxiety and Depression in US Adults With Arthritis 971
Prevalence and correlates of anxiety. At least half of Among those with anxiety, depression, or both, more
the people in the following 6 subgroups reported anxi- than half (55%) of all respondents had not sought help in
ety: unemployed, unable to work, or disabled (62%); the past year. This was only slightly improved when lim-
respondents who reported “a lot” of difficulty with bath- ited to those who were currently seeing a doctor or HCP for
ing or dressing (63%), “a lot” of interference with er- their arthritis or joint symptoms (46%) (Table 3). Across
rands or household chores in the past 7 days (51%), or all sociodemographic groups, 36 – 66% of respondents had
that their arthritis or joint symptoms affected whether not sought help (Table 3), and among those who were
they worked for pay (52%); severe fatigue in the past 7 currently seeing a doctor or HCP for their arthritis or joint
days (50.2%); and no confidence in their ability to engage symptoms, the range was 21– 61%. Similar patterns were
in moderate physical activity at least 3 times/week (56%) observed among those with each of anxiety, depression,
(Table 1). and both conditions (data not shown).
Almost all of the independent variables were signifi-
cantly associated with anxiety in unadjusted models (Ta- DISCUSSION
ble 1). In the multivariable model, anxiety was signifi-
cantly higher among respondents who were ages 45– 64 One-third of respondents with arthritis had anxiety, de-
years (PR 1.7; referent: age ⱖ65 years), reported severe pression, or both. Anxiety was almost twice as common as
joint pain in the past week (PR 1.9; referent: no pain), and depression (31% and 18%, respectively), and virtually all
reported good (PR 1.4) or poor/fair self-rated health (PR respondents with depression also had anxiety. Approxi-
1.6; referent for self-rated health: excellent/very good) (Ta- mately half of the respondents with anxiety and/or depres-
ble 2). Anxiety was also higher among respondents who sion had sought help for their mental health condition in
had no or moderate confidence in their ability to engage in the past year. Most of the statistically significant associa-
moderate physical activity at least 3 times/week (PRs 1.5 tions observed in the multivariable analysis were moder-
and 1.3, respectively; referent: high confidence) (Table 2). ately strong; nevertheless, a distinct profile of characteris-
After multivariable adjustment, respondents who were tics of those with anxiety and depression did not emerge.
overweight or obese were 20% less probable to report We found that anxiety was more common than depres-
anxiety (PR 0.8) (Table 2). sion in this population-based sample of people with ar-
thritis, a pattern that has been observed in clinic-based
Prevalence and correlates of depression. Depression samples (4,12–14,16). Anxiety can elicit independent and
prevalence was highest among those who reported “a lot” at least equally debilitating effects as depression (5,31,32).
of difficulties bathing or dressing themselves (48%) (Table Despite this and the high prevalence of anxiety in previous
1). At least one-third of people in the following subgroups studies, few influential rheumatology texts (33) mention anx-
reported depression: unemployed, unable to work, or dis- iety, suggesting that the magnitude and impact of this prob-
abled (45%); Hispanics (37%); severe fatigue in the past 7 lem among people with arthritis are underrecognized (31).
days (36.3%); and respondents whose arthritis or joint The US Preventive Services Task Force recommends
symptoms affected whether they worked for pay (33%), screening of all adults for depression when systems are in
who had “a lot” of interference with errands or household place to ensure accurate diagnosis, effective treatment, and
chores in the past 7 days (36%), who had no or a low level appropriate followup; there is insufficient evidence sup-
of confidence in their ability to manage their arthritis or porting universal screening when effective treatment and
joint symptoms (34% and 45%, respectively), or who had followup are unavailable (34). HCPs do not appear to rou-
no confidence in their ability to engage in moderate phys- tinely and systematically screen for anxiety or depression
ical activity at least 3 times/week (42%). (35). We believe that screening of all people with arthritis
Several correlates of depression were observed in unad- for anxiety and depression is indicated when the same
justed models (Table 1). In multivariable models, depres- conditions (e.g., effective treatment) are met. Although
sion was significantly more common among those who there are differences in the treatment for depression and
were ages 45– 64 years (PR 1.6; referent: age ⱖ65 years), anxiety, pharmacotherapy and cognitive– behavioral ther-
reported low confidence in their ability to manage their apy are considered effective methods of treating depres-
arthritis or joint symptoms (PR 2.3), and had only moder- sion and many forms of anxiety (20). Furthermore, the
ate confidence in their ability to engage in moderate phys- appropriate treatment of depression among people with
ical activity at least 3 times/week (PR 1.5) (Table 2). arthritis can lead to clinically significant reductions in
pain, improved functional outcomes, and continued com-
Prevalence of help seeking for anxiety and depression pliance with antidepressant use for at least 1 year follow-
in the past year. Help seeking was highest among people ing treatment (36). For this reason, treating existent mental
with both conditions (57.1%) and lowest among those health conditions should be regarded as a fundamental
with anxiety only (45.1%; people with depression ⫽ part of managing arthritis symptoms. Both anxiety and
51.3%) (data not shown). Respondents were most likely to depression were common among respondents who were
have sought help from their doctor (82– 83%), followed by currently being seen by an HCP for their arthritis and joint
family and friends (45– 46%); therapist/counselor (43– symptoms, but approximately half of those reporting anx-
46%); priest, minister, rabbi, or other religious counselor iety or depression had not sought help for their mental
(15–16%); and self-help or support groups (11–13%; sum health conditions in the past year. HCP visits for manage-
exceeds 100% because respondents sought help from mul- ment of arthritis symptoms may be an opportunity to
tiple sources). screen for and treat anxiety and depression.972 Murphy et al
Table 1. Associations of sociodemographic, disease, and physical function and health behaviors, self-management, and self-
efficacy with each of anxiety and depression: prevalence and unadjusted PRs*
Anxiety Depression
Prevalence Unadjusted Prevalence Unadjusted
(95% CI) PR (95% CI) (95% CI) PR (95% CI)
Sociodemographic
Age, years
45–64 39.3 (35.7–42.9) 1.9 (1.6–2.3) 21.8 (18.9–24.8) 1.7 (1.4–2.2)
ⱖ65 20.6 (17.5–23.6) 1.0 12.6 (10.0–15.2) 1.0
Sex
Men 26.2 (22.1–30.4) 1.0 15.0 (11.7–18.2) 1.0
Women 33.5 (30.6–36.3) 1.3 (1.1–1.5) 19.1 (16.7–21.4) 1.3 (1.0–1.6)
Race/ethnicity
Non-Hispanic white 28.8 (26.1–31.5) 1.0 22.5 (16.2–28.8) 1.0
Hispanic 45.6 (33.9–57.3) 1.6 (1.2–2.1) 37.3 (25.9–48.8) 2.4 (1.7–3.4)
Non-Hispanic black 32.7 (25.7–39.8) 1.1 (0.9–1.4) 16.8 (7.4–26.1) 1.5 (1.1–2.0)
Non-Hispanic other† 40.1 (27.1–53.1) 1.4 (1.0–2.0) 15.4 (13.3–17.5) 1.1 (0.6–1.9)
Education
Less than high school 44.1 (37.6–50.5) 2.3 (1.8–2.9) 31.5 (25.4–37.6) 3.8 (2.6–5.6)
High school or some college 32.2 (29.0–35.4) 1.7 (1.3–2.1) 17.9 (15.3–20.5) 2.2 (1.5–3.1)
Completed college or greater 19.3 (15.4–23.1) 1.0 8.1 (5.4–10.8) 1.0
Employment status
Employed 28.4 (24.1–32.7) 1.0 12.5 (9.4–15.5) 1.0
Unemployed, unable to work, or disabled‡ 62.4 (56.6–68.1) 2.2 (1.8–2.6) 44.8 (38.6–51.0) 3.5 (2.7–4.6)
Retired 31.1 (23.7–38.5) 0.7 (0.6–0.9) 11.1 (8.7–13.6) 0.9 (0.6–1.2)
Other§ 19.6 (16.5–22.6) 1.1 (0.8–1.5) 14.1 (8.7–19.6) 1.1 (0.7–1.7)
Disease and physical function
No. of days in the past week with pain, aching, or
stiffness
None 11.5 (7.2–17.8) 1.0 4.5 (2.4–8.3) 1.0
1 or 2 19.8 (14.7–26.2) 1.7 (1.0–3.0) 9.2 (5.9–14.0) 2.1 (1.0–4.4)
3 or 4 30.7 (24.3–37.9) 2.7 (1.6–4.4) 12.9 (8.7–18.9) 2.9 (1.4–6.0)
ⱖ5 35.8 (32.7–38.9) 3.1 (2.0–4.9) 21.8 (19.3–24.5) 4.9 (2.6–9.2)
Severity of joint pain in the past 7 days
None (0) 9.0 (5.2–15.1) 1.0 5.4 (2.6–11.0) 1.0
Low (1–3) 19.7 (15.6–24.7) 2.2 (1.2–4.0) 7.6 (5.1–11.1) 1.4 (0.6–3.2)
Moderate (4–6) 28.8 (25.3–32.5) 3.2 (1.9–5.6) 15.6 (13.0–18.7) 2.9 (1.4–6.1)
Severe (7–10) 46.9 (42.2–51.7) 5.2 (3.0–9.0) 31.1 (26.9–35.7) 5.7 (2.7–12.0)
Severity of joint stiffness in the past 7 days
None (0) 14.3 (9.5–19.0) 1.0 6.9 (3.6–10.1) 1.0
Low (1–3) 20.1 (15.3–24.8) 1.4 (0.9–2.1) 9.2 (5.6–12.8) 1.3 (0.7–2.5)
Moderate (4–6) 29.7 (25.8–33.7) 2.1 (1.5–3.0) 16.6 (13.4–19.7) 2.4 (1.4–4.1)
Severe (7–10) 48.2 (43.4–52.9) 3.4 (2.4–4.8) 30.4 (26.1–34.7) 4.4 (2.7–7.3)
Severity of fatigue in the past 7 days
None (0) 12.4 (8.7–16.0) 1.0 6.0 (3.3–8.7) 1.0
Low (1–3) 18.9 (14.1–23.7) 1.5 (1.0–2.3) 7.9 (4.6–11.2) 1.3 (0.7–2.4)
Moderate (4–6) 34.0 (29.5–38.6) 2.8 (2.0–3.8) 14.9 (11.6–18.2) 2.5 (1.5–4.1)
Severe (7–10) 50.2 (45.5–55.0) 4.1 (3.0–5.6) 36.3 (31.8–40.9) 6.0 (3.8–9.6)
Self-reported general health status in the past 7 days
Very good/excellent 16.5 (13.1–19.9) 1.0 7.1 (4.8–9.4) 1.0
Good 27.0 (22.9–31.0) 1.6 (1.3–2.1) 13.8 (10.7–16.9) 2.0 (1.3–2.9)
Poor/fair 48.3 (44.0–52.7) 2.9 (2.3–3.6) 31.0 (27.0–35.1) 4.4 (3.1–6.2)
Limited in any way because of arthritis or joint
symptoms
No 20.5 (17.5–23.6) 1.0 10.4 (8.2–12.6) 1.0
Yes 39.8 (36.3–43.3) 1.9 (1.6–2.3) 23.8 (20.7–26.8) 2.2 (1.8–2.9)
Difficulty bathing or dressing yourself?
A little/none 27.9 (25.4–30.3) 1.0 14.9 (12.9–16.8) 1.0
A lot 62.8 (54.3–71.2) 2.2 (1.9–2.6) 47.7 (38.7–56.7) 3.2 (2.5–4.0)
Difficulty walking several hundred feet
A little/none 25.2 (22.5–27.9) 1.0 12.1 (10.2–14.1) 1.0
A lot 46.0 (41.0–50.9) 1.8 (1.6–2.1) 32.4 (27.8–37.1) 2.7 (2.1–3.3)
(continued)Anxiety and Depression in US Adults With Arthritis 973
Table 1. (Cont’d)
Anxiety Depression
Prevalence Unadjusted Prevalence Unadjusted
(95% CI) PR (95% CI) (95% CI) PR (95% CI)
Difficulty bending, kneeling, or stooping
A little/none 21.6 (18.6–24.5) 1.0 10.4 (8.2–12.6) 1.0
A lot 41.0 (37.3–44.6) 1.9 (1.6–2.2) 25.4 (22.3–28.6) 2.4 (1.9–3.1)
Do arthritis or joint symptoms now affect whether
you work for pay or not?
No 21.5 (18.9–24.1) 1.0 10.3 (8.4–12.2) 1.0
Yes 51.8 (47.2–56.4) 2.4 (2.1–2.8) 33.0 (28.6–37.3) 3.2 (2.5–4.0)
Did arthritis or joint symptoms interfere with
errands or shopping in the past 7 days?
A little/none 24.8 (22.2–27.3) 1.0 12.2 (10.4–14.1) 1.0
A lot 51.1 (45.8–56.4) 2.0 (1.8–2.4) 36.4 (31.2–41.5) 3.0 (2.4–3.6)
Satisfaction with current ability to do usual
activities
Somewhat satisfied/very satisfied 20.0 (17.3–22.6) 1.0 9.4 (7.5–11.3) 1.0
Neutral 39.0 (28.3–49.7) 2.0 (1.4–2.7) 20.2 (11.5–28.9) 2.1 (1.3–3.4)
Somewhat dissatisfied/very dissatisfied 48.1 (43.6–52.5) 2.4 (2.0–2.8) 31.4 (27.3–35.5) 3.3 (2.6–4.2)
Health and self-management behaviors
Body mass index, kg/m2
Under- and normal weight (⬍25) 31.1 (26.8–35.5) 1.0 14.7 (11.4–18.0) 1.0
Overweight (25 to ⬍30) 25.5 (21.6–29.4) 0.8 (0.7–1.0) 13.5 (10.5–16.5) 0.9 (0.7–1.3)
Obese (ⱖ30) 36.0 (31.7–40.3) 1.2 (1.0–1.4) 23.6 (19.8–27.4) 1.6 (1.2–2.1)
Physical activity level¶
Meets recommendations 26.4 (23.4–29.6) 1.0 12.8 (10.7–15.3) 1.0
Insufficient 29.8 (25.3–34.8) 1.1 (0.9–1.4) 17.2 (13.7–21.3) 1.3 (1.0–1.8)
Inactive 42.8 (37.4–48.4) 1.6 (1.4–1.9) 30.6 (25.7–36.1) 2.4 (1.9–3.1)
Have you ever taken a self-management education
course?
No 30.2 (27.7–32.8) 1.0 17.0 (15.0–19.0) 1.0
Yes 34.7 (26.8–42.5) 1.1 (0.9–1.5) 21.9 (15.2–28.6) 1.3 (0.9–1.8)
Confidence that a self-management education course
would help manage symptoms
No confidence 25.4 (19.8–31.1) 0.9 (0.7–1.1) 17.0 (12.2–21.9) 1.1 (0.7–1.5)
Low (1–3) 30.8 (24.8–36.8) 1.1 (0.8–1.3) 16.9 (12.1–21.7) 1.1 (0.8–1.5)
Moderate (4–6) 34.4 (29.9–38.9) 1.2 (1.0–1.4) 18.6 (15.1–22.1) 1.2 (0.9–1.6)
High (7–10) 29.2 (25.0–33.3) 1.0 16.1 (12.8–19.4) 1.0
Confidence in ability to manage arthritis or joint
symptoms
No confidence 45.7 (32.5–59.0) 2.0 (1.4–2.7) 34.3 (21.5–47.2) 3.0 (2.0–4.5)
Low (1–3) 49.3 (38.4–60.2) 2.1 (1.6–2.7) 44.7 (33.9–55.6) 3.9 (2.9–5.3)
Moderate (4–6) 40.6 (35.6–45.6) 1.7 (1.5–2.1) 22.3 (18.2–26.4) 1.9 (1.5–2.5)
High (7–10) 23.4 (20.5–26.2) 1.0 11.5 (9.4–13.5) 1.0
Confidence in ability to engage in moderate physical
activity at least 3 times/week
No confidence 55.8 (45.5–66.2) 2.5 (2.0–3.1) 42.4 (31.8–53.0) 4.1 (3.0–5.6)
Low (1–3) 48.0 (38.7–57.3) 2.1 (1.7–2.6) 30.5 (22.2–38.9) 3.1 (2.2–4.2)
Moderate (4–6) 40.2 (34.9–45.5) 1.8 (1.5–2.1) 25.6 (20.9–30.3) 2.5 (1.9–3.2)
High (7–10) 22.7 (20.0–25.4) 1.0 10.3 (8.4–12.2) 1.0
Currently being treated by doctor or HCP for
arthritis or chronic joint symptoms?
No 26.0 (22.9–29.2) 1.0 13.5 (11.0–15.9) 1.0
Yes 35.5 (31.9–39.2) 1.4 (1.2–1.6) 21.8 (18.7–24.8) 1.6 (1.3–2.0)
* PR ⫽ prevalence ratio; 95% CI ⫽ 95% confidence interval; HCP ⫽ health care provider.
† Alaska Native/American Indian, Asian, and Native Hawaiian or other Pacific Islander.
‡ Disabled and unable to work were combined because of small sample sizes.
§ Homemakers and students were combined because of small sample sizes.
¶ Categories were: recommended (ⱖ150 minutes), insufficient (10 –149 minutes), or inactive (⬍10 minutes), where 1 minute of vigorous exercise was
equivalent to 2 minutes of moderate activity.
The relationship across anxiety, depression, and pain is dently and synergistically as a risk factor and outcome for
complex, with evidence that each condition acts indepen- each other (10,11,37). Furthermore, each is an indepen-974 Murphy et al
treated because it can be an appropriate response to stress-
Table 2. Sociodemographic, physical, and psychosocial
characteristics associated with anxiety and depression: ful life events and circumstances, and therefore treatment
statistically significant multivariable adjusted PRs* may not seem indicated (7). In fact, psychosocial distress
among people with arthritis may signal the presence of
Anxiety, Depression, other threats to their well-being, such as economic insecu-
PR (95% CI) PR (95% CI) rity (the prevalence of each of anxiety and depression in
Sociodemographics
our study was higher among those who were unemployed,
Age, years disabled, or unable to work) (38). In at least one study,
45–64 1.7 (1.3–2.1) 1.6 (1.1–2.2) anxiety was an even stronger predictor of functional lim-
ⱖ65 1.0 1.0 itations than depression among people with arthritis (5),
Arthritis symptoms and physical and it can be an obstacle to the behavioral changes asso-
health and function ciated with reducing pain and depression, such as physi-
Severity of joint pain in the cal activity. Minor and Brown examined the efficacy of an
past 7 days† exercise program for people with arthritis, and both high
No pain (0) 1.0 1.0 baseline anxiety and depression scores were indepen-
Low (1–3) 1.6 (1.0–2.5) 1.3 (0.6–2.7)
dently associated with an increased risk of not exercising
Moderate (4–6) 1.6 (1.0–2.5) 1.6 (0.8–3.2)
Severe (7–10) 1.9 (1.2–3.0) 1.8 (0.9–3.6)
at 3, 9, and 18 months postintervention (32).
Self-reported general health Ideally, treatment and management of anxiety and de-
status pression include simultaneous clinical and self-manage-
Very good/excellent 1.0 1.0 ment interventions. There are multiple inexpensive,
Good 1.4 (1.1–1.7) 1.4 (1.0–2.0) convenient, and evidence-based self-management inter-
Poor/fair 1.6 (1.2–2.1) 1.5 (1.0–2.3) ventions for anxiety and depression that complement clin-
Health and self-management ical care. Aerobic exercise is an effective treatment for
behaviors mild to moderate depression and is associated with reduc-
Body mass index, kg/m2 1.0 tions in anxiety (39); some strength training activities may
Under- and normal weight 0.8 (0.7–1.0)
(⬍25)
Overweight (25 to ⬍30) 0.8 (0.7–0.9) Table 3. Percentage with anxiety, depression, or both in
Obese (ⱖ30) 1.0 the past month who have not sought help in the past 12
Confidence in ability to months for “stress, depression, or problems
manage arthritis or joint with emotions”
symptoms
Currently
No confidence 1.1 (0.6–1.9)
being treated
Low (1–3) 2.3 (1.6–3.3)
for arthritis or
Moderate (4–6) 1.2 (0.9–1.6)
Overall joint symptoms
High (7–10) 1.0
Confidence in ability to engage
Overall 55 46
in moderate physical
Age, years
activity at least 3 times/
45–64 50 43
week
ⱖ65 65 56
No confidence 1.5 (1.1–2.1) 1.5 (1.0–2.3)
Sex
Low (1–3) 1.2 (1.0–1.6) 1.1 (0.8–1.7)
Men 60 53
Moderate (4–6) 1.3 (1.1–1.6) 1.5 (1.2–2.1)
Women 53 43
High (7–10) 1.0 1.0
Race/ethnicity
* The multivariable adjusted model comprised all but 1 variable Hispanic 40 40
examined in unadjusted models. This table shows statistically sig- Non-Hispanic black 63 21
nificant associations only; PRs for all variables examined in this Non-Hispanic other* 53 53
multivariable model are shown in Supplementary Table 1 (available Non-Hispanic white 56 48
in the online version of this article at http://onlinelibrary.wiley.
com/journal/10.1002/(ISSN)2151-4658). PR ⫽ prevalence ratio; Highest level of education
95% CI ⫽ 95% confidence interval. Less than high school 60 57
† Severity of each of fatigue, joint stiffness, and joint pain was High school or some college 53 46
highly correlated (r ⫽ 0.7). To reduce collinearity, only the latter Completed college or greater 55 51
was included in the multivariable models; joint pain was selected
because it is generally the most modifiable symptom among people Employment status
with arthritis, and was also strongly associated with both anxiety Employed 66 61
and depression (see Table 1). Because severity of pain was highly Unemployed, unable to work, 37 32
correlated with number of days in the past week with pain, aching, or disabled†
or stiffness (r ⫽ 0.6), only severity of pain was included in the
multivariable models. Retired 66 57
Other‡ 55 39
dent determinant of disability, further complicating this * Alaska Native/American Indian, Asian, and Native Hawaiian or
other Pacific Islander.
interrelationship. Similar to depression, anxiety can per- † Disabled and unable to work were combined because of insuffi-
sist and worsen if untreated (7); the importance of ad- cient sample sizes.
‡ Homemakers and students were combined because of insufficient
dressing anxiety is emerging only now (18). Kessler et al sample sizes.
propose that anxiety may be underrecognized and under-Anxiety and Depression in US Adults With Arthritis 975
also elicit the same effects for depression (29). For those tion had a high positive predictive value (44). Second,
wanting guidance on safely exercising, community-based ACHES is a cross-sectional study and it is not known
physical activity programs (e.g., Walk With Ease, Enhance- whether the correlates studied are predictors or sequelae
Fitness) teach people with arthritis strategies to reach of anxiety and depression. Third, several 95% CIs in both
recommended levels of physical activity without exac- unadjusted and multivariable analyses bordered on statis-
erbating symptoms or worsening disease (40). SME inter- tical significance, especially for depression, for which
ventions (e.g., Chronic Disease Self-Management Program, there were fewer people affected. This suggests that there
Arthritis Self-Management Program) have been proven to was insufficient power to detect modest statistically sig-
lead to reductions in anxiety and depression (40). There- nificant associations. Last, despite multiple strategies to
fore, another strategy for HCPs is recommending par- maximize survey participation, response rates were low,
ticipation in physical activity and evidence-based SME particularly among blacks and Hispanics. A previous ana-
interventions (http://www.cdc.gov/arthritis/interventions. lysis indicated that the sociodemographic characteristics
htm). Recommendation from an HCP is key; ACHES re- of ACHES respondents are similar to adults with arthritis
spondents who had received a recommendation from their ages ⱖ45 years in the nationally representative NHIS (22),
HCP to attend an SME class were 18.5 times more likely to suggesting that ACHES results are generalizable to the US
report attending one than those without a recommenda- population.
tion (41). ACHES is the most comprehensive population-based
AIMS anxiety and depression subscales were used to national survey of US adults with arthritis to date. We
define these conditions. AIMS is one of the most com- found that both anxiety and depression are common
monly used and reported instruments for the study of among people with arthritis and the prevalence of anxiety
anxiety and depression among people with rheumatic con- was higher than the prevalence of depression. A distinct
ditions (4,13–16). As mentioned previously, although profile of people with these conditions was not evident
AIMS subscales have not been validated directly in pop- because the prevalence of these conditions was relatively
ulation-based studies, the AIMS depression subscale is high across all of the subgroups. Approximately half of the
strongly correlated (r ⫽ 0.81) with the CES-D (42), a pop- affected respondents whose arthritis was being treated by
ulation measure of depression symptoms. Increasing lev- an HCP had not sought treatment in the past year for their
els of AIMS depression and anxiety scores are also asso- mental health condition, indicating a missed opportunity
ciated with lower levels of physical function (measured for HCP intervention. This is important because HCPs can
with the Health Assessment Questionnaire [HAQ]) (4,13), have a significant impact on reducing the burden of anxi-
suggesting construct validity. To our knowledge, the AIMS ety and depression among people with arthritis through
anxiety subscale has not been validated against any other systematic screening for both conditions, treatment based
population-based measure of anxiety. We believe there is on current standards of care, and their strong influence in
construct validity to the anxiety subscale because of the recommending physical activity and SME programs to
association between anxiety and HAQ physical function their patients.
scores (4,13). Also, we found that having sought help in
the past 12 months for mental health conditions was ACKNOWLEDGMENTS
strongly associated with both anxiety (PR 3.5, 95% CI The authors would like to thank the Battelle staff for co-
2.9 – 4.2) and depression (PR 3.4, 95% CI 2.9 – 4.0) (data ordinating all aspects of ACHES, the ACHES steering
not shown), suggesting that the subscales detect mental group’s expertise and time in development of the survey,
distress. and the ACHES respondents for their participation in this
The types of anxiety disorders (e.g., generalized anxiety study.
disorder, panic disorder) detected by the AIMS anxiety AUTHOR CONTRIBUTIONS
subscale have not been characterized. Also, because symp- All authors were involved in drafting the article or revising it
toms of anxiety can be a manifestation of depression (43), critically for important intellectual content, and all authors ap-
proved the final version to be published. Dr. Murphy had full
the proportion of anxiety among respondents attributable
access to all of the data in the study and takes responsibility for
to depression is unknown. the integrity of the data and the accuracy of the data analysis.
Our estimates indicate that the population burden of Study conception and design. Murphy, Sacks, Brady, Hootman,
anxiety and depression among adults with arthritis is sub- Chapman.
stantial, but may be underestimated for several reasons. Acquisition of data. Sacks.
Analysis and interpretation of data. Murphy, Hootman, Chapman.
We used a conservative definition of depression (i.e., the
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