Long-term follow-up on health-related quality of life in major depressive disorder: a 2-year European cohort study

Figures & data

Figure 1 (A) Mean SF-12 MCS and SF-12 PCS total scores (total analyzable population, N=1,159), (B) EQ-5D utility index score (UK only, N=276), (C) PHQ-9 score (N=1,159), and (D) PDQ-5 score (N=1,159), over time. Data are mean ± standard error. For SF-12 and EQ-5D, higher scores indicate improved outcome; for PHQ-9 and PDQ-5, higher scores indicate worse outcome.

Abbreviations: EQ-5D, EuroQol Five Dimensions questionnaire; MCS, mental component summary; PCS, physical component summary; PDQ-5, 5-item Perceived Deficit Questionnaire; PHQ-9, 9-item Patient Health Questionnaire; SF-12, Medical Outcomes Study Short-Form 12-item Health Survey.

Figure 2 Scores for (A) SF-12 MCS, (B) SF-12 PCS, and (C) EQ-5D utility index, categorized by PDQ-5 total score quartile at baseline, month 2, month 6/month 12, and month 18/month 24.

Notes: ^aBaseline: PDQ-5 total score quartiles at baseline; month 2, month 6/month 12, and month 18/month 24: PDQ-5 total quartiles score at month 2.
Abbreviations: EQ-5D, EuroQol Five Dimensions questionnaire; MCS, mental component summary; PCS, physical component summary; PDQ-5, 5-item Perceived Deficit Questionnaire; SF-12, Medical Outcomes Study Short-Form 12-item Health Survey.

Figure 3 Scores for (A) SF-12 MCS, (B) SF-12 PCS, and (C) EQ-5D utility index, categorized by PHQ-9 total score category at baseline, month 2, month 6/month 12, and month 18/month 24.

Notes: ^aBaseline: PHQ-9 total score at baseline; month 2, month 6/month 12, and month 18/month 24: PHQ-9 total score at month 2.
Abbreviations: EQ-5D, EuroQol Five Dimensions questionnaire; MCS, mental component summary; PCS, physical component summary; PHQ-9, 9-item Patient Health Questionnaire; SF-12, Medical Outcomes Study Short-Form 12-item Health Survey.

Table 1 Results of the multivariate analysis of patient characteristics associated with SF-12 MCS and PCS total scores at baseline, month 2, and month 6/month 12

Patient characteristic	Baseline (N=691)		Month 2 (N=572)		Month 6/month 12 (N=919)a
	SF-12 MCS	SF-12 PCS	SF-12 MCS	SF-12 PCS	SF-12 MCS	SF-12 PCS
Baseline sociodemographics
Country	P=0.015	P<0.001	P<0.001	P<0.001	P=0.627	P<0.001
France	0.81±0.94	−0.91±1.29	−1.96±1.02	−1.42±1.24	0.47±1.10	−1.08±1.13
Spain	2.61±1.04	−3.59±1.43	2.58±1.19	−4.15±1.44	−0.47±1.34	−3.99±1.33
UK	−0.29±0.96	5.85±1.30	−1.60±1.04	3.17±1.27	−0.05±1.12	1.37±1.88
Sweden	2.07±1.43	1.54±1.94	−1.78±1.68	−1.07±2.00	−2.54±1.98	−3.03±1.96
Germany	–	–	–	–	–	–
Age (years)	P=0.002	P<0.001	P=0.014	P<0.001	P=0.434	P<0.001
18–34	−2.74±0.87	5.48±1.18	−2.80±1.00	5.23±1.18	−0.54±1.12	5.86±1.12
35–54	−0.46±0.72	4.04±0.98	−0.72±0.83	3.53±0.98	0.68±0.90	4.23±0.90
55–65	–	–	–	–	–	–
Sex: male vs female	P=0.128	P=0.047	P=0.105	P=0.966	P=1.000	P=0.125
	−0.98±0.64	1.75±0.88	−1.26±0.78	0.04±0.91	0.00±0.89	−1.35±0.88
Educational level	P=0.016	P<0.001	P=0.018	P<0.001	—	P<0.001
Elementary school	2.52±0.84	−5.56±1.15	1.92±1.00	−5.02±1.17		−4.43±1.09
High school	1.91±0.77	−3.08±1.04	1.47±0.91	−2.77±1.06		−2.07±1.00
Non-university degree	2.03±1.00	−1.19±1.36	3.56±1.14	−1.05±1.34		−0.68±1.28
University degree	–	–	–	–		–
Clinical characteristics
CGI-S scoreb	—	—	—	—	P=0.002	—
1–3					4.30±1.28
4					2.46±1.27
5–7					–
PHQ-9 scoreb	P<0.001	P=0.008	P<0.001	P<0.001	P<0.001	P<0.001
0–4	20.38±3.43	6.60±4.66	18.75±1.67	10.06±1.97	12.76±1.95	10.52±1.86
5–9	9.77±1.29	6.14±1.75	9.41±1.28	7.36±1.51	8.69±1.48	8.74±1.41
10–14	5.58±0.91	2.69±1.24	5.83±1.20	6.02±1.42	6.41±1.36	6.60±1.32
15–19	2.69±0.71	2.06±0.97	2.40±1.17	4.07±1.37	2.49±1.34	5.06±1.31
20–27	–	–	–	–	–	–
PDQ-5 scoreb	P<0.001	P<0.001	P<0.001	P<0.001	P=0.003	P=0.023
0–7	5.03±1.03	6.13±1.40	5.41±1.19	5.66±1.39	5.03±1.37	4.03±1.33
8–11	3.91±0.85	4.53±1.16	2.72±1.10	3.69±1.28	2.53±1.21	2.07±1.18
12–14	2.70±0.81	2.43±1.09	1.40±1.02	1.68±1.19	1.73±1.14	1.21±1.12
15–20	–	–	–	–	–	–
Chronic pain or fibromyalgia at baseline: yes vs no	P<0.001	P<0.001	—	P<0.001	—	P<0.001
	3.35±0.77	−6.69±1.06		−6.92±1.00		−7.29±0.96
Hospitalization for depression:c yes vs no	—	P=0.019	—	—	—	—
		−5.30±2.26
Sick leave:d yes vs no	—	P<0.001	–	P=0.029	—	—
		−3.00±0.86		−1.80±0.82
Treatment characteristics
Switch of antidepressant at baseline: yes vs no	—	P<0.001	—	—	—	—
		−3.50±0.99

Notes: Data shown are coefficients (±standard error). Coefficients show the change in the respective score between the specified levels for each characteristic. Patient characteristics with P<0.2 in the univariate ANOVA (shown in Table S2) were retained in the multivariate ANCOVA. Country, age, and sex (baseline values) and PHQ-9 score were forced in the analysis. A long dash (—) indicates that the patient characteristic listed was either not included or not kept in the final analysis for that outcome; a short dash (–) indicates the reference category.

a Sum of the number of patients at the two visits.

b Baseline CGI-S, PHQ-9, and PDQ-5 scores used in the analysis of HRQoL outcomes at baseline; month 2 CGI-S, PHQ-9, and PDQ-5 scores used in the analysis of HRQoL outcomes at month 2 and month 6/month 12.

c Within 12 weeks before baseline for HRQoL outcomes at baseline; between baseline and month 2 for HRQoL outcomes at month 2 and month 6/month 12.

d Within 12 months before baseline for HRQoL outcomes at baseline; within 12 months before baseline or at baseline or between baseline and month 2 for HRQoL outcomes at month 2 and month 6/month 12.

Abbreviations: ANOVA, analysis of variance; ANCOVA, analysis of covariance; CGI-S, Clinical Global Impression–Severity of illness scale; HRQoL, health-related quality of life; MCS, mental component summary; PCS, physical component summary; PDQ-5, 5-item Perceived Deficit Questionnaire; PHQ-9, 9-item Patient Health Questionnaire; SF-12, Medical Outcomes Study Short-Form 12-item Health Survey.

Table 2 Results of the multivariate analysis of patient characteristics associated with EQ-5D utility index score at baseline, month 2, month 6/month 12, and month 18/month 24 (UK population only)

Patient characteristic	EQ-5D utility index
	Baseline (N=259)	Month 2 (N=201)	Month 6/month 12 (N=309)a	Month 18/month 24 (N=251)a
Baseline sociodemographics
Age (years)	P=0.006	P=0.216	P=0.004	P=0.094
18–34	0.11±0.05	0.00±0.04	0.12±0.04	0.11±0.05
35–54	0.14±0.04	0.05±0.04	0.12±0.04	0.08±0.04
55–65	–	–	–	–
Sex: male vs female	P=0.008	P=0.257	P=0.107	P=0.106
	−0.09±0.03	−0.04±0.03	−0.05±0.03	0.07±0.04
Clinical characteristics
CGI-S scoreb	P<0.001	—	—	—
1–3	0.23±0.06
4	0.16±0.05
5–7	–
PHQ-9 scoreb	P=0.022	P<0.001	P<0.001	P<0.001
0–4	NA	0.53±0.06	0.45±0.06	0.28±0.07
5–9	0.24±0.08	0.46±0.04	0.38±0.05	0.28±0.05
10–14	0.10±0.06	0.36±0.04	0.33±0.05	0.22±0.06
15–19	0.06±0.04	0.29±0.04	0.25±0.05	0.13±0.06
20–27	–	−	–	–
PDQ-5 scoreb	P<0.001	—	—	—
0–7	0.19±0.06
8–11	0.13±0.05
12–14	0.16±0.04
15–20	–
Suicide attempt:c yes vs no	—	—	P<0.001	P=0.002
			−0.20±0.05	−0.20±0.06
At least one other concomitant mental disorder at baseline: yes vs no	—	P=0.019	—	—
		−0.16±0.07
At least one anxiety symptom/disorder at baseline: yes vs no	P=0.023	—	—	—
	−0.07±0.03
Chronic pain or fibromyalgia at baseline: yes vs no	P=0.013	P<0.001	P<0.001	P<0.001
	−0.14±0.06	−0.23±0.04	−0.19±0.05	−0.30±0.06
Hospitalization for depression:d yes vs no	—	—	—	P=0.027
				−0.50±0.22
Treatment characteristics
Treatment line at month 2	—	P=0.005	P=0.003	—
1		0.03±0.08	−0.25±0.08
2		−0.08±0.08	−0.28±0.08
≥3		–	–

Notes: Data shown are coefficients (±standard error). Coefficients show the change in the respective score between the specified levels for each characteristic. Patient characteristics with P<0.2 in the univariate ANOVA (shown in Table S3) were retained in the multivariate ANCOVA. Age, sex (baseline values), and PHQ-9 score were forced in the multivariate analysis. A long dash (—) indicates that the factor listed was either not included or not kept in the final model for that outcome; a short dash (–) indicates the reference category.

a Sum of the number of patients at the two visits.

b Baseline CGI-S, PHQ-9, and PDQ-5 scores used in the analysis of HRQoL outcomes at baseline; month 2 CGI-S, PHQ-9, and PDQ-5 scores used in the analysis of HRQoL outcomes at month 2, month 6/month 12, and month 18/month 24.

c Before baseline for HRQoL outcomes at baseline; before baseline or between baseline and month 2 for HRQoL outcomes at month 2, month 6/month 12, and month 18/month 24.

d Within 12 weeks before baseline for HRQoL outcomes at baseline; between baseline and month 2 for HRQoL outcomes at month 2, month 6/month 12, and month 18/month 24.

Abbreviations: ANOVA, analysis of variance; ANCOVA, analysis of covariance; CGI-S, Clinical Global Impression–Severity of illness scale; EQ-5D, EuroQol Five Dimensions questionnaire; HRQoL, health-related quality of life; NA, not available; PDQ-5, 5-item Perceived Deficit Questionnaire; PHQ-9, 9-item Patient Health Questionnaire.