MindMed ISPOR 2024: Health-related Quality of Life Associated with Generalized Anxiety Disorder among Adults in the United States

Health-related Quality of Life Associated with Generalized Anxiety Disorder among Adults in the United States

Phong Duong1, Susan J. Suponcic2, Kyla Finlayson3, Vicky Li3, Daniel Karlin1

1 MindMed, New York, NY, USA, 2 Value & Access Advisors, LLC, St Petersburg, FL, USA, 3 Oracle Life Sciences, Austin, TX

PCR38

Introduction

• Generalized anxiety disorder (GAD) is one of the most prevalent anxiety disorders in the general population.1
• GAD is related to interference with performing daily activities, lower role functioning and social functioning, and higher rates of comorbid disorders.2,3
• However, the impact of GAD on health-related quality of life (HRQoL) has been underexplored.

Objective

This study aimed to quantify the association of GAD with HRQoL, overall, and by symptom severity among the general population of US adults.

Study Design

• This is a cross-sectional retrospective study.

Data Source

• This study included data from the 2022 National Health and Wellness Survey (NHWS; N=75,261).
• The NHWS is an annual internet-based survey; all data are self-reported. Recruitment is designed to represent the general US adult population in terms of age, race/ethnicity, and gender distributions.
• As part of the NHWS survey, respondents reported on 1) demographics, health characteristics, and comorbidities; 2) GAD diagnosis and treatment; and completed 1) the 7-time GAD questionnaire (GAD-7); 2) HRQoL assessments.

Inclusion Criteria

• Aged 18-64 years.
• Resident of the US.
• Completed 2022 US NHWS.
• Self-reporteda diagnosis of GAD (diagnosed GAD group) or screened negative for GAD (GAD-7 score <10) and reported no diagnosis of GAD (controls).4

Exclusion Criteria

• Participants with other mental health conditions or cancer.
• Screened positive for bipolar disorder on Mood Disorder Questionnaire (MDQ).5
• Self-reporteda diagnosis of bipolar disorder and/or schizophrenia.
• Self-reporteda diagnosis of any type of cancer.

Methods

Variables

• Exposure (GAD by symptom severity vs. control)
• Adults (aged 18-64 years) diagnosed with GAD were categorized by symptom severity using scores on the GAD-7 screening tool: no (n=872, 0-4); mild (n=1,381, 5-9); moderate (n=1,100, 10-14); and severe (n=1,080, ≥15) GAD symptoms.4
• Controls were defined as reporting no diagnosis of GAD and having a negative screen (n=36,505, GAD-7<10).

HRQoL Outcomes

• HRQoL includes the EQ-5D index score and the visual analog scale (EQ-VAS). Higher EQ-5D index and EQ-VAS scores represent better HRQoL.6
• HRQoL also includes RAND-36 Global, Physical, and Mental Health Composite [GHC, PHC, MHC] scores. RAND-36 scores range 0-100, with higher scores reflecting better HRQoL.7

Covariates

• Demographics include age, gender, race/ethnicity, marital status, education, household income, employment status, and health insurance.
• Health characteristics include obesity and smoking status, and depression status.8,9
• Undiagnosed depression was defined as having a positive screen for depression (the Patient Health Questionnaire-9≥10) and reported no depression diagnosis.10
• Comorbidities include self-reported cardiovascular/cerebrovascular conditions, pain, high cholesterol, pulmonary conditions, sleep disorder, diabetes, and other mental health conditions.

Data Analysis

• Patients diagnosed with GAD by symptom severity were compared with controls on HRQoL outcomes using generalized linear models (GLMs; normal distribution, identity link).
• Covariates were adjusted in the GLMs.
• Adjusted means and 95% confidence intervals (CIs) were reported. P-values <0.05, 2-tailed were considered to be statistically significant.

Demographics, Health Characteristics, and Comorbidities

• The total study sample had average age of 41.5 years, and 52.9% were female.
• Overall, compared with controls, those with diagnosed GAD were:
• Slightly younger and more likely to be female; (Table 1)
• Less likely to be married/living with partner, educated, and employed; (Table 1)
• Had lower income; (Table 1)

Table 1. Demographics and health characteristics of diagnosed GAD and control

	Diagnosed GAD	Control
N	4,433	36,505
Age (years), Mean ± SD	38.60 ± 14.57	41.88 ± 13.53
Female, N (%)	3,514 (79.27%)	18,136 (49.68%)
Race/ethnicity, N (%)
Non-Hispanic white	2,769 (62.46%)	21,704 (59.45%)
Non-Hispanic black	471 (10.62%)	5,001 (13.70%)
Hispanic	697 (15.72%)	6,177 (16.92%)
Other	496 (11.19%)	3,623 (9.92%)
Married/living with partner, N (%)	1,864 (42.05%)	23,174 (63.48%)
College educated, N (%)	1,568 (35.37%)	20,268 (55.52%)
Annual household income, N (%)
$75K or more	1,211 (27.32%)	20,420 (55.94%)
$50K to <$75K	752 (16.96%)	5,106 (13.99%)
<$50K	2,252 (50.80%)	9,472 (25.95%)
Decline to answer	218 (4.92%)	1,507 (4.13%)
Employed, N (%)	2,466 (55.63%)	27,596 (75.60%)
Insurance, N (%)
Private insurance	2,331 (52.58%)	21,729 (59.52%)
Public insurance	1,592 (35.91%)	6,013 (16.47%)
No insurance	397 (8.96%)	7,630 (20.90%)
Insured, unknown type	113 (2.55%)	1,133 (3.10%)
Body mass index category, N (%)
Not obese	2,430 (54.82%)	23,519 (64.43%)
Obese	1,758 (39.66%)	8,544 (23.41%)
Decline to answer	245 (5.53%)	4,442 (12.17%)
Smoking behavior, N (%)
Non-smoker	2,341 (52.81%)	24,889 (68.18%)
Former smoker	1,112 (25.08%)	4,856 (13.30%)
Current smoker	980 (22.11%)	6,760 (18.52%)

Abbreviations: GAD: generalized anxiety disorder; SD: standard deviation.

Results

• Compared with controls, those with diagnosed GAD had dramatically increased risk of being diagnosed with comorbidities. (Table 2)

Table 2. Comorbidities of no-GAD, undiagnosed GAD, and diagnosed GAD

	Diagnosed GAD	Control
N	4,433	36,505
Depression, N (%)
No depression	591 (13.33%)	27,682 (75.83%)
Diagnosed depression	3,559 (80.28%)	3,982 (10.91%)
Undiagnosed depression	283 (6.38%)	4,841 (13.26%)
Diagnosed with cardiovascular/cerebrovascular condition,	1,469 (33.14%)	6,679 (18.30%)
N (%)
Diagnosed with pain condition, N (%)	2,499 (56.37%)	7,107 (19.47%)
Diagnosed with bone/joint condition, N (%)	1,282 (28.92%)	5,038 (13.80%)
Diagnosed with high cholesterol, N (%)	1,072 (24.18%)	4,726 (12.95%)
Diagnosed with pulmonary condition, N (%)	974 (21.97%)	2,422 (6.63%)
Diagnosed with Other mental health condition, N (%)	2,739 (61.79%)	2,061 (5.65%)
Diagnosed with sleep disorder, N (%)	1,844 (41.60%)	3,335 (9.14%)
Diagnosed with diabetes, N (%)	507 (11.44%)	2,401 (6.58%)

GAD with EQ-5D

• EQ-5Ddata by GAD symptom severity are shown in Figure 1.
• Compared with controls (0.84, 95% CI: 0.84-0.84), adjusted EQ-5D index scores were significantly lower among the mild (0.80), moderate (0.75), and severe (0.66) GAD groups.
• Adjusted EQ-5D index scores decreased as severity worsened among adults diagnosed with GAD (mild: 0.80,
  95% CI: 0.79-0.81, moderate: 0.75, 95% CI: 0.74-0.76, and severe GAD: 0.66, 95% CI: 0.65-0.67).
• Similarly, compared with controls (76.3, 95% CI: 76.1-76.5), adjusted EQ-VAS scores were significantly lower among the mild (72.7), moderate (69.7), and severe (65.0) GAD groups.
• Adjusted EQ-VAS scores decreased as severity worsened among adults diagnosed with GAD (mild: 72.7, 95%
  CI: 71.4-74.0, moderate: 69.7, 95% CI: 68.3-71.2, and severe GAD: 65.0, 95% CI: 63.5-66.6).
• Adjusted EQ-VAS scores were significantly higher among adults with diagnosed GAD who had no GAD symptoms (78.1, 95% CI: 76.5-79.7) than controls (76.3, 95%CI: 76.1-76.5).

GAD with RAND-36

• RAND-36scores by GAD symptom severity are shown in Figure 2.
• Compared with controls (45.3, 95%CI: 45.2-45.4), adjusted GHC scores were significantly lower among the mild, moderate, and severe GAD groups (35.0-41.5).
• Adjusted GHC scores decreased as severity worsened among adults diagnosed with GAD (mild: 41.5, 95% CI: 41.0-42.0, moderate:
  38.3, 95% CI: 37.8-38.9, and severe GAD: 35.0, 95% CI: 34.4-35.6).
• Adjusted GHC scores were significantly higher among adults with diagnosed GAD who had no GAD symptoms (46.8, 95%CI: 46.1-
  47.4) than controls (45.3, 95% CI: 45.2-45.4).
• A similar trend was observed for MHC and PHC scores.
• The magnitude of difference in MHC scores was larger than the difference observed in PHC scores, suggesting a greater impact of GAD symptom severity on mental health functioning than physical health functioning.

Figure 1. Scores on EQ-5D index and EQ-VAS: GAD by symptom severity vs. controls

	0.90	0.84	0.84	EQ-5D											90.00				*		EQ-VAS
										*
										0.80	*									76.29	78.10	*		*
	0.80									0.75							80.00
													*											72.70	69.72	*
Mean	0.70																	0.66		Mean	70.00												65.05
0.60																						60.00
0.50																						50.00
Adjusted																						Adjusted
0.30																						30.00
	0.40																							40.00
	0.20																							20.00
	0.10																							10.00
	0.00																							0.00
No GAD	GAD- None/Minimal	GAD- Mild GAD- Moderate GAD- Severe		No GAD	GAD- None/Minimal	GAD- Mild GAD- Moderate	GAD- Severe

Figure 2. Scores on Global Health Composite, Mental Health Composite, and Physical Health Composite: GAD by symptom severity vs. controls

	60.00
				*																			*															*		*
	50.00																														47.27	48.34		*
	45.33	46.75	*											44.83	46.23								46.17		*
																						44.59
							*										*																				42.61
									41.52
										*					39.66	*
	40.00													38.33
Mean																	35.03											35.83	*
Adjusted	30.00																																				32.17
20.00

10.00

0.00

Global Health Composite T-Score (GHC)	Mental Health Composite Score (MHC)	Physical Health Composite Score (PHC)
No GAD	GAD- None/Minimal	GAD- Mild	GAD- Moderate	GAD- Severe

Note. Groups that were statistically significant at p<0.05, 2-tailed, compared with controls (no-GAD) are marked with asterisks. Abbreviations: GAD: generalized anxiety disorder; VAS: visual analog scale.

Strengths and limitations

Limitations

• Our study is cross-sectional and thus cannot provide evidence of causality for the associations between GAD and HRQoL.
• All data collected in the survey were self-reported, and survey responses may potentially be affected by recall error or other response biases.

Strengths

• This study adds to the limited existing knowledge of the impact of GAD symptoms on HRQoL, with validated scales used to evaluate HRQoL in a real-world setting.
• An extensive list of covariates selected based on findings of other published research was adjusted in our models to reduce potential confounding effects.
• The large representative sample allows for greater generalizability of the findings.
• To define our study cohorts, we used the GAD-7 scale, which has demonstrated good validity and reliability in the general population,4,11 to screen for GAD.

Conclusions

Overall, GAD was	Adults who were diagnosed	Adults who were diagnosed	Adults who were diagnosed with GAD, but had no	Findings highlight the
associated with higher	with GAD and had moderate	with GAD had increasing	GAD symptoms had similar or lower HRQoL burden	need to reduce GAD
HRQoL burden, from	or severe GAD symptoms had	HRQoL burden with severity	than controls. Future research is needed to	symptom severity to
both physical and mental	higher HRQoL burden than	of GAD symptoms.	understand how GAD symptom management may	potentially alleviate the
health perspective.	controls.		translate into lower HRQoL burden than control.	HRQoL burden of GAD.

References

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Acknowledgements: The study was funded by Mind Medicine Inc