Background The improved survival of patients with Systemic Lupus Erythematosus (SLE) over the past decades highlighted the problem of co-morbidity (several different chronic pathologies presence) in SLE patients because many of them reach the age when the burden of concomitant diseases could increase and become ordinary.
Objectives To evaluate the frequency of concomitant diseases and to estimate the total co-morbidity status in SLE patients.
Methods The retrospective study of co-morbidity in SLE patients was conducted on the database of Byelorussian Republican Rheumatologic Center. It included 212 patients: 192 women and 20 men at the age of 16.1 to 68.3 (mean ± SD: 33.2±12.3 years) at the baseline (first visit). The diagnosis of SLE was in conformance with 1997 ACR modified classification criteria for SLE . The comprehensive assessment of patient co-morbidities was performed by Kaplan-Feinstein co-morbidity index (KFI)  which includes twelve pathology categories: arterial hypertension (HT), heart disease (HD) presence, nervous system (ND) involvement, respiratory system (RD) pathology, vascular (VD), kidney (KD), liver (LD) gastrointestinal (GID) and musculoskeletal (MSD) diseases, other pathology (OD), malignancies and alcoholism. A co-morbidity score of 1 indicates low level of co-morbidity, 2 - moderate and 3 - high level of co-morbidity for corresponding pathology. The possible grade of co-morbidity is calculated as a sum score for all categories and varies from 0 to 36 points.
Results KFI in SLE patients at the first visit varied from 0 to 7 points (Me: 2; 25–75% range: 0–3) and had minor differences in age and sex groups (NS, Fisher's exact test). One-third of patients (n=68) had no co-morbidities.
One of the most common pathology was HT which was diagnosed in 39 patients (18.4%, 95% CI 5.6–26.7%): 34 women and 5 men (p=0.591, NS, Fisher's exact test). Over the 13-year follow-up period the frequency of HT dramatically increased to 52.9% (95% CI 37.0–68.0%) i.e. 2.9 times vs baseline (p<0,001). Prognostic odds ratios (pOR) of HT were 7.6 (95% CI 3.1–18.2) and 3.2 (1.4–7.6) for lupus nephritis presence and signs of glucucorticoid disease (“cushingoid”), correspondingly.
Other common co-morbidities were GID and HD. Coronary HD and congestive heart failure were revealed in 43 (20.3%) patients. GID were registered in 44 (20.8%) patients, among them 9 (4.2%) patients had gastric/duodenal ulcer. VD, ND and RD were revealed in 7 (3.3%) patients for each category, KD and LD frequency was 6 (2.8%) for both pathology. MSD were registered in 8 (3.8%) and OD, including different infections, anemia, diabetes etc. were registered in 39 (18.4%) patients. There were no cases of malignancies or alcoholism in our patients.
Conclusions Total co-morbidity status revealed in SLE patients at baseline varied up to the 20 percent of the maximal possible level for all age and sex groups. Arterial hypertension was one of the most common pathology which demonstrated significant and predictable growth over the 13-year follow-up period.
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Disclosure of Interest None declared