Sleep profile in rheumatoid arthriti : a polysomnographic evaluation of egyptian patients

الملخص EN

Sleep disturbances are a frequent complaint in RA patients and they might contribute to pain and other daytime complaints.

To address this issue, we designed the present study to assess the pattern of sleep changes in a sample of Egyptian RA patients.

We compared their sleep recordings to those obtained in healthy controls and examined the correlations between variable parameters of disease activity and both subjective and objective indicators of sleep disturbances.

All patients passed a clinical examination and completed different questionnaires.

Sleep recordings were obtained from twenty outRA patients besides twenty matched controls.

Detailed analysis of sleep through polysomnographic assessment and microstructure of sleep was performed.

Sixteen out of the twenty studied patients (80%) had some sort of sleep complaint.

Twelve patients (60%) described non-restorative sleep (non-refreshing sleep); six (30%) described disorder of excessive somnolence; four (20%) reported difficulty in falling asleep and two (10%) described early morning awakening.

Whereas normal sleep architecture is conserved in RA, we confirmed former findings of sleep fragmentation and the presence of primary sleep disorders in the form of frequent movements of the extremities (PLM) in 12 patients (60%); alpha delta-sleep was noted in 9 patients (45%).

Other recorded abnormalities included a significantly higher number of arousals in the patients more than in the controls; a significantly delayed sleep latency in the patients; significantly reduced sleep efficiency where the t-values were 3.5 and -3.6 respectively.

Also, the percentage of stages I and III were significantly higher in patients than the controls(t=5.6 and 1.64 respectively).

Otherwise, minor differences were observed in classical sleep stages.

No correlation existed between RA activity and parameters of sleep pathology.

So sleep is disrupted in some RA patients regardless of the inflammatory disease activity.

However, making a step by step analysis for each activity item, significant positive correlation between PLM and the following parameters for disease activity were found; joint swelling (0.5049); morning stiffness (0.4043) and ESR (0.8432).

The implications and specificity of the sleep disorders assessed should be further investigated.

Since cytokines (IL-1 and TNF-?) play a central role in the immunopathogenesis of RA and are also described as being somnogenic, therefore it is important to evaluate the effect of the newer anti-cytokine therapy on sleep structure.

Moreover, it will be important to determine whether pharmacologic suppression of the extremity movement and/or arousals reduces the feeling of daytime complaints in RA patients.