Background/Purpose: Delays in patient presentation to primary care providers,  subsequent referral for rheumatology assessment, and recognition of rheumatoid arthritis (RA) by the rheumatologist increase time to diagnosis. This time period is a modifiable determinant of joint damage and affects the odds of entering remission, and factors impacting this time must be elicited. Our aim was to evaluate whether time to diagnosis is influenced by measures of disease severity or a family history of RA, sociodemographic factors affecting access to care (age, sex, socioeconomic status [SES], education level, ethnicity), or comorbidities that may influence the physical examination, such as obesity, mental health conditions, or other musculoskeletal pain conditions.

Methods: A prospective national cohort of patients with confirmed or possible RA by 2010 ACR criteria (n=1,151) was evaluated for predictors of the duration of time to diagnosis. Variables examined in univariate analysis are summarized in Table 1. Simple linear regression was applied to each variable, and significant predictors carried forward to multivariate linear regression.

Results:

TABLE 1. Variables Assessed in Univariate Analysis for Time to Diagnosis
Female	74%
Age, mean (SD)	54 (14.7) years
Caucasian ethnicity	83%
BMI, mean (SD)	28.6 (10.5)
DAS28, mean (SD)	5.02 (1.44)
Swollen joint count, mean (SD)	28 Joints: 7.7 (6.0); 66 Joints: 9.8 (7.9)
Tender joint count, mean (SD)	28 Joints: 8.3 (6.5); 66 Joints: 12.7 (9.4)
HAQ, mean (SD)	1.02 (0.70)
Patient Global (VAS 0-10), mean (SD)	5.7 (2.9)
Acute Phase Reactants, mean (SD)	ESR: 28.1 (22.6) mm/hr; CRP: 14.4 (17.8) mg/L
Serology	Rheumatoid factor positive 67%; Anti-CCP positive 58%
Education	Only elementary or high school 46%; College or post-secondary 51%
Annual Income	<$20,000: 12%; $20,000-$50,000: 24%; $50,000-$100,000: 18%; >$100,000: 8%
Mental Health Condition	Depression: 11%; Other: 1%
Fibromyalgia	2%
Osteoarthritis	11%
Family History of RA	22%

The mean symptom duration at the baseline rheumatology visit was 6.0 months (range 0.1-19.6). In univariate analysis, age, joint counts, DAS28, patient global, HAQ, ESR, CRP, education level and anti-CCP status were all significant predictors (p<0.05) for time to diagnosis, whereas BMI, sex, ethnicity, income, RF status, family history of RA, and history of depression, fibromyalgia or osteoarthritis had no effect. In multivariate analysis, higher swollen joint counts, higher ESR, worse patient global scores, and negative anti-CCP antibody status were significant predictors of shorter time to diagnosis (Table 2).

TABLE 2. Multivariate Analysis for Predictors of Time to Diagnosis
Parameter	Estimate	95% CI	P-value
Intercept	7.789	7.257; 8.322	<.0001
Swollen Joints	-0.051	-0.089; -0.013	0.0085
ESR	-0.016	-0.026; -0.006	0.0017
Patient Global Score	-0.085	-0.161; -0.009	0.0280
Damaged joint count	-0.090	-0.204; 0.023	0.1192
Anti-CCP Positive	0.814	0.383; 1.245	0.0002

Conclusion: Recognition of RA is not affected by a family history, sociodemographic factors, body habitus, mental health conditions, or other musculoskeletal pain syndromes. Worse patient global, more swollen joints, higher ESR and anti-CCP status influence time to diagnosis. The impact of fewer swollen joints and normal laboratory parameters on delay to diagnosis merits further consideration.

---

« Back to 2012 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/disease-activity-and-anti-ccp-status-but-not-sociodemographic-factors-or-patient-comorbidities-affect-time-to-diagnosis-in-early-rheumatoid-arthritis/