Background/Purpose: Patients with rheumatic diseases have significantly better clinical status in recent years than in previous decades, including rheumatoid arthritis (RA)¹ and systemic lupus erythematosus (SLE).²  Therefore, many items in the health assessment questionnaire (HAQ) which were almost always elevated in 1980 when the HAQ³ was reported may be normal at this time.  In 1999, 16% of patients were reported to have HAQ scores of zero, suggesting “no difficulty” in function, but most nonetheless reported problems with function as well as psychosocial issues reflecting “floor effects.” Therefore, a multidimensional HAQ (MDHAQ) was developed to include 13 queries in the user-friendly HAQ format, 8 simple activities of daily living (ADL) from (and identical to) the HAQ, and 5 not on the HAQ: 2 complex activities – “walk 2 miles or 3 kilometers” and “participate in recreation and sports as you would like”, and 3 “psychological” queries – sleep quality, anxiety and depression.  We analyzed mean scores for each of the 13 MDHAQ items in patients with RA and SLE in routine care in an academic rheumatology setting. 

Methods: An MDHAQ is completed in an academic rheumatology setting by each patient at each visit.  The MDHAQ queries 13 items (Table) in the patient-friendly HAQ format, all scored 0-3, with 4 response options: without any difficulty=0, with some difficulty=1, with much difficulty=2 and unable to do=3. Mean scores were analyzed in 140 female patients, 70 who met criteria for RA and 70 for SLE.  Mean scores for each item was computed and compared using a t-test with a p-value of ≤ 0.05 considered significant on 2-tailed tests.  Exploratory factor analysis (Principal Component analysis with varimax rotation) on the 13 items was performed. 

Results: Mean scores for the 8 items a-h found on the HAQ were <0.70 in patients with RA and <0.50 in patients with SLE (Table), but scores were >0.70 in patients with RA and >0.50 in patients with SLE for all 5 items i-m found only on the MDHAQ. Scores of 0 (floor effects) were seen in >49% of RA and >63% of SLE patients for the HAQ and MDHAQ items vs <47% for RA and <54% of SLE patients for the unique MDHAQ items.  Most items loaded into 3 Components: A: activities of simple living (a-h in SLE and items a-c, e-g in RA), B: complex activities (i and j) and C: psychological (k-m). Differences between RA and SLE patients were significant only for items a, b and j.

Conclusion: Scores of 0 are seen on considerably more HAQ items than MDHAQ items.  The MDHAQ identifies patient problems, which are not captured by the HAQ, similar in RA and SLE. Documentation of improvement is not possible when baseline scores are zero. The MDHAQ might be considered for usual clinical care as well as in clinical trials.

References:

1.      Sokka T et al. Clin Exp Rheumatol. 2008 Sep-Oct; 26:S35-61.

2.      Urowitz MB et al. J Rheumatol. 1997; 24(6):1061-1065.

3.       Fries JF et al. Arthritis Rheum. 1980;23(2):137-45.