Subjective sleep disturbances at the time of diagnosis in patients with polymyalgia rheumatica and in patients with seronegative elderly-onset rheumatoid arthritis. A pilot study.

Abstract

ObjectivesTo investigate subjective sleep disturbances in patients with recent-onset polymyalgia rheumatica (PMR) and in patients with recent-onset seronegative elderly-onset rheumatoid arthritis (SEORA).Material and methodsThe study involved patients consecutively referred to two outpatient clinics from January to June 2018, with a diagnosis of PMR according to 2012 European League Against Rheumatism and American College of Rheumatology provisional criteria, and patients with a diagnosis of SEORA according to 1987 American Rheumatism Association criteria + age + absence of rheumatoid factor and anti-citrullinated peptide antibodies. All patients were naive to glucocorticoid (GC) therapy. After informed consent, we asked the patients to fill out a questionnaire including the Medical Outcomes Study – Sleep Scale (MOS-SS), pain Visual Analogic Scale (VAS), Cumulative Illness Rating Scale (CIRS), Neuropsychiatric Inventory (NPI), and how many minutes their morning stiffness (MS) lasted, at baseline and after 1 (T1) and 12 (T2) months. Differences between groups were calculated with the t-test; all p-values were two-sided and p < 0.05 was used to determine statistical significance. The study was approved by the local ethics committee and carried out in accordance with the Helsinki Declaration.ResultsThe MOS-SS scores and MS duration were the only variables to show at T0 a significant difference between the two groups. In particular, MOS-SS scores were 47.6 ±8.4 (PMR) and 28.26 ±12.4 (SEORA), with p-values = 0.000. The MS duration was 90 ±9.9 minutes and 45 ±5.5 minutes, with p-value = 0.000. At T1 and T2, MOS-SS scores and MS duration decreased in the two groups, and no significant differences were found.ConclusionsThe study suggests that the assessment of subjective sleep disturbances can be useful in the differential diagnosis between recent-onset PMR and SEORA.